“Starspots” on Betelgeuse: JCMT Explains Star’s Record-Breaking Dimming

New data obtained using the Hawai`i-based James Clerk Maxwell Telescope (JCMT) revealed that the surface of Betelgeuse (commonly known as Orion’s shoulder), recently developed significant “Starspots” which caused an unprecedented dimming of the star. This result contrasts the previously accepted explanation that the reduction in brightness was due to a veil of newly created dust that obscured the star. The research was published today in the prestigious Astrophysical Journal Letters.

An artist’s rendering of Betelgeuse, Dr. Thavisha Dharmawardena from the Max Planck Institute for Astronomy, and Dr. Steve Mairs from the James Clerk Maxwell Telescope

Beginning in October, 2019, the Red Supergiant star, Betelgeuse, experienced a record-breaking dimming event where it became three times fainter than usual. This phenomenon captured the interest of both professional astronomers and the public, largely fuelled by curiosity in the red supergiant’s demise and whether this change in brightness was heralding an imminent supernova explosion. In an anti-climactic conclusion, however, the star eventually increased in brightness again to its regular appearance. The explanation that emerged at the time was that the dimming was caused by a newly formed cloud of dust that blocked some of the light before it reached our telescopes here on Earth. An independent study led by Dr. Thavisha Dharmawardena, postdoctoral researcher at the Max Planck Institute for Astronomy, Germany, and Dr. Steve Mairs, Senior Scientist at the James Clerk Maxwell Telescope, Hawai`i, USA, however, offers the more likely explanation that the surface of Betelgeuse itself underwent a significant change.

Like tuning to a different radio station in a car, telescopes are each tuned to observe different types of light. In this way, observations from different telescopes can be combined to help fill in the whole picture. “​By using the James Clerk Maxwell Telescope here in Hawai`i, we were able to collect a type of light called ‘submillimetre light’ that is not visible to the human eye,”​ Mairs explains, “​This provided the crucial information that allowed us to conclude that there was no dust in the way; Betelgeuse was feeling shy with a face full of spots.”​

An artist’s impression of the Red Supergiant Betelgeuse. Its surface is covered by large starspots, which reduce its brightness. During their pulsations, such stars regularly release gas into their surroundings, which condenses into dust. (Image: Graphics Department/MPIA).

New JCMT images were obtained in January, February, and March, 2020 while Betelgeuse was faint and they were compared with observations taken over the past 13 years. These previous observations include images obtained by the Atacama Pathfinder Experiment (APEX), a telescope in Chile that observes the same type of light as the JCMT. “​What surprised us was that Betelgeuse turned 20% darker during its dimming event even in submillimetre light,”​ Dharmawardena says “​This behaviour is not at all compatible with the presence of dust. It was very exciting to realise that the star itself had undergone this massive change​”.

According to the scientists, the simultaneous darkening in visible and submillimetre light is evidence for a reduction in the mean surface temperature of Betelgeuse by 200 °C (360 °F). ​“However, an asymmetric temperature distribution is more likely,”​ Dharmawardena explains, referring to corresponding high-resolution images of Betelgeuse from December 2019 that depict an uneven distribution of stellar brightness.​ “Together with our result, this is a clear indication of huge starspots covering between 50 and 70% of the visible surface, each having a lower temperature than the rest of the surface.”​ Starspots, similar to sunspots, are common in giant stars, but not on this scale. Not much is known about their lifetime. However, theoretical model calculations seem to be compatible with the duration of Betelgeuse’s dip in brightness.

The team will continue to track the brightness of Betelgeuse with the JCMT over the next year to uncover more details about how the star is physically changing over different timescales. ​“Previous generations of stars like Betelgeuse have physically manufactured most of the elements we find on Earth and indeed in our bodies, distributing them throughout the Galaxy in massive supernova explosions.”​ Mairs explains. ​“While we cannot predict when the star will explode, tracking its brightness will allow us not only to better understand the evolution of an interesting class of stars, but it also helps write a page in our own cosmic story.”


Supplementary information about Betelgeuse:

Betelgeuse, known as Kauluakoko in `ōlelo Hawaii, is the nearest red supergiant star to the Earth at a distance of only 500 light years. It is the red shoulder of the constellation Orion. It is so large that if Betelgeuse were to be placed at the location of our Sun, Mercury, Venus, the Earth, Mars, and the asteroid belt, would all be contained inside the star. With such a close proximity, it acts as a unique laboratory to aid in the understanding of the late stages of red supergiant evolution. Massive stars (Betelgeuse is 11 times heavier than our Sun) are important to study as they are the main drivers of chemical evolution in the universe. Stars like Betelgeuse manufacture many of the elements that comprise our bodies and our planet and even before the explosive end of their lives, massive stars undergo episodes wherein they lose material, enriching their surroundings with newly formed chemical elements. These periods of mass loss are accompanied by pulsations with periods of up to a few years.

Supplementary Information about the JCMT:

With a diameter of 15m (50 feet) the James Clerk Maxwell Telescope (JCMT) is the largest astronomical telescope in the world designed specifically to operate in the submillimetre wavelength region of the electromagnetic spectrum. The JCMT is used to study our Solar System, interstellar and circumstellar dust and gas, evolved stars, and distant galaxies. It is situated in the science reserve of Maunakea, Hawai`i, at an altitude of 4092m (13,425 feet).

The JCMT is operated by the East Asian Observatory on behalf of NAOJ; ASIAA; KASI; CAMS as well as the National Key R&D Program of China. Additional funding support is provided by the STFC and participating universities in the UK and Canada​. Supplementary Information about SCUBA-2:

The James Clerk Maxwell Telescope (JCMT) observations were obtained using the “Submillimetre Common User Bolometer Array 2”, a specialised camera known by its acronym, SCUBA-2. SCUBA-2 consists of 10,000 superconducting Transition Edge Sensor (TES) bolometers that allow for simultaneous observations at wavelengths of 450 and 850 microns. Scientists regularly use SCUBA-2 to observe star-forming regions, Red Giant stars, and the most distant galaxies ever discovered. At an operating temperature of -459.5 degrees fahrenheit, SCUBA-2 at the JCMT is one of the coldest places in the known Universe.

Contact Information:

Dr. Thavisha Dharmawardena
Max Planck Institute for Astronomy
Email: ​dharmawardena@mpia.de

Dr. Steve Mairs
James Clerk Maxwell Telescope
East Asian Observatory
Email: ​s.mairs@eaobservatory.org

Dr. Jessica Dempsey
James Clerk Maxwell Telescope
East Asian Observatory
Email: ​j.dempsey@eaobservatory.org

New OMP and JCMOT log in system

The JCMT software team has been working hard to create a way for projects to be accessed by individual user log in rather than project wide shared log in/passwords. Going forward, to access programs in the OMP and JCMTOT  you will need to log in via  your Hedwig account.

PIs will be able to choose who has access on each project’s contacts page.  An advantage of the new system will be that you need only log in once to access all of your projects.

A helpful guide to these changes is provided in this OMP and OT access guide.

JCMT user are also reminded that a new version of the JCMT Observing Tool (JCMTOT) has been released.


Accessing the OMP:


The new JCMTOT and the JCMTOT log in window:

JCMT Telescope Operator Featured on CBS “Mission Unstoppable”

JCMT Telescope System Specialist Mimi Fuchs is on the front page of the Hawaii Tribune-Herald  today showcasing her appearance in an episode of “Mission Unstoppable” on CBS. As well as being an operator at the JCMT Mimi is an IF/THEN Ambassador for the AAAS – The American Association for the Advancement of Science.

Read the full Hawaii Tribune-Herald article here.

Watch the “Mission Unstoppable” segment here.

EAO and ‘Imiloa provide ‘Stellar’ Night to local Cub Scouts

On Saturday, March 7th, 2020, the ‘Imiloa Astronomy Center in Hilo, Hawai’i hosted 70 visitors for a special overnight event.  As part of the “Stellar Night at the Museum”, the Cub Scouts and their family members were treated to a unique visit at the East Asian Observatory base facility.

Courtesy photo provided to the Hawaii Tribune Herald from the Cub Scouts who attended the Scouts Stellar Night at the Museum overnight March 7 at ‘Imiloa Astronomy Center in Hilo.


Telescope System Specialist, Alexis Acohido, provided tours into the JCMT Control Room as live operations were taking place. Photo taken by Emily Peavy.


Extended Operator, Patrice Smith, engaged the visitors with a fun “Alien Eyes” activity that demonstrated how filters can help us sort out information that we wouldn’t be able to normally see with our eyes. Photo taken by Emily Peavy.


EAO Visiting Scientist, Pablo Torne, used spectral tubes and diffraction gratings to explore spectral lines from different molecules. Photo taken by Emily Peavy.


In the UKIRT control room, Telescope Operators Jess Stasik and Michael Pohlen used an infrared camera and a cell phone to explore heat. Photo taken by Emily Peavy.

An article was released in the local Hawaii Tribune Herald newspaper about the event, and can be read here:



The Event Horizon Telescope brings the world together to observe new mysteries in quasar 3C 279

First Event Horizon Telescope Observations of a Black-Hole Powered Jet announced as Maunakea Observatories offer MKO@Home online resources

Two Hawai’i-based telescopes, the James Clerk Maxwell Telescope (JCMT), operated by the East Asian Observatory, and the Submillimeter Array (SMA), operated by the Smithsonian Astrophysical Observatory and the Academia Sinica Institute for Astronomy and Astrophysics, have once again provided crucial information in the global effort to understand Black Holes. The JCMT and SMA linked up with six other telescopes around the world to form the Event Horizon Telescope (EHT), in an effort involving hundreds of astronomers and engineers. The black hole targeted in these observations resides at the centre of a galaxy called 3C 279. This galaxy is 5 billion light years away in the direction of the Virgo constellation.

Nearly one year ago, the JCMT and the SMA played a vital role in the groundbreaking EHT observational campaign to observe the very first image of a black hole, which was given the Hawaiian name Pōwehi. The EHT collaboration is excited to announce this new result from data obtained at the same time as the Pōwehi result.

For the first time, astronomers have observed a jet travelling at close to the speed of light, that is believed to originate from the vicinity of a supermassive black hole, in unprecedented detail. In their analysis, led by astronomer Jae-Young Kim from the Max Planck Institute for Radio Astronomy in Bonn (MPIfR), the collaboration studied the exquisite detail of the jet’s shape close to the base. The jet base is a fascinating region where highly variable, high energy gamma-ray emission is thought to originate.

The results will be published in the coming issue of the prestigious journal ​Astronomy & Astrophysics​.


Fig. 1: Illustration of 3C 279 jet structure in April 2017. The observing epochs, arrays, and frequencies are noted at the top of each panel. Credit: J.Y. Kim (MPIfR) & the Event Horizon Telescope Collaboration


The black hole targeted in these observations is called 3C 279. It resides at the centre of a galaxy 5 billion light years away in the direction of the constellation Virgo. Scientists classify this galaxy as a quasar because it shines ultra-bright and flickers, signifying that massive amounts of gases and stars are falling into the giant black hole at the centre. The black hole in 3C 279 is about one billion times the mass of our own sun. Any material such as stars, gas, or dust that comes close to this black hole is shredded by strong gravitational forces, causing a large donut-shaped structure known as an accretion disc to form around the object. But not all of this shredded material stays in the accretion disc or ends up falling into the Super Massive Black Hole. Some of the material will be squirted back out into space in two fine fire-hose-like jets of plasma, travelling at speeds near the speed of light. These jets are powerful and demonstrate the enormous forces at play in the centre of this galaxy.

Through linking up many telescopes across the globe, using a technique known as very long baseline interferometry (VLBI), the astronomers are able to see the jet and accretion disc in action, distinguishing the sharpest-ever details in the jet. The new jet images, probing size scales finer than a light-year, show an unexpected twisted shape at its base, and features perpendicular to the jet, which could represent the poles of the accretion disc from where jets are ejected. Through comparing the images of 3C 279 over subsequent days, the astronomers see the finest details changing, opening up the possibility that we are actually seeing both the rotation of the accretion disc (with the shredding and infall of material), and the jet ejection, that has previously only been modeled in computer simulations of these objects.

Jae-Young Kim, leader of the analysis, is enthusiastic and at the same time puzzled: “We knew that every time you open a new window to the Universe you can find something new. Here, where we expected to find the region where the jet forms by going to the sharpest image possible, we find a kind of perpendicular structure. This is like finding a very different shape by opening the smallest Matryoshka doll.” Furthermore, the fact that the images change so fast has also surprised astronomers. “These jets show apparent motions faster than the speed of light (called superluminal motion), as an optical illusion, but this, perpendicular to the expectation, is new and requires careful analysis”, adds Jae-Young-Kim.

The interpretation of these observations is challenging. In particular, observing apparent motions of about 20 times the speed of light in the jet are difficult to reconcile with the early understanding of the source. These results paint a complex picture, where disturbances in the flow of material, known as shocks, are travelling down a bent (and possibly rotating) jet, and producing incredibly high energy gamma-rays.

“To announce this incredible result exactly a year after we brought Pōwehi to the world makes it so special,” offers Jessica Dempsey, Deputy Director of the James Clerk Maxwell Telescope – one of the two Hawaii-based observatories that are part of the EHT. “For our staff here in Hawaii, it is a reminder of the ground-breaking work they continue to contribute to – even if we aren’t up at the summit right now. Like Pōwehi before it, this beautiful image of 3C 279 gives me hope, for us and for our future.”

Fig. 2: The James Clerk Maxwell Telescope (JCMT) located on the slopes of Maunakea, Hawai`i is pictured in the foreground. The JCMT is operated by the East Asian Observatory. Credit: Will Montgomerie

Anton Zensus, Director at the MPIfR and Chair of the EHT Collaboration Board, stresses the achievement as a global effort: “Last year we could present the first image of the shadow of a black hole. Now we see unexpected changes in the shape of the jet in 3C 279, and we are not done yet. We are working on the analysis of data from the centre of our Galaxy in Sgr A*, and on other active galaxies such as Centaurus A, OJ 287, and NGC 1052. As we told last year: this is just the beginning.”

The March/April 2020 observing campaign of the EHT was cancelled due to the CoViD-19 global outbreak. The EHT Collaboration is now determined on the next steps to follow both in new observations and in the analysis of existing data. Geoff Bower, EHT Project Scientist based at the SMA facility in Hilo concludes: ​“This is a small piece of good news during this challenging time. We’re very happy to share with the world results from telescopes on Maunakea and around the globe the insights that we have made into black holes, the most exotic objects in the Universe. Both the SMA and the JCMT produced essential data to make these spectacular images, just as they did for Pōwehi. Stay tuned for new discoveries in the year still to come!”

Here in Hawaii, the state’s effort to “flatten the curve” in the fight against CoViD-19 means that many families now have children – keiki – distance learning at home. Together the Maunakea Observatories are supporting our community by providing online STEM resources for schools, teachers and families. The MKO@Home initiative was launched on March 23rd providing educational videos each Monday, Wednesday and Friday. Topics covered include careers, the solar system, recent discoveries, arts and crafts and more. This week MKO@Home will offer a range of activities and lessons involving Black Holes with a culminating event on April 10th, the State of Hawaiʻi’s Pōwehi Day. Four astronomy professionals will host a live panel discussion at 1:00pm HST answering viewers’ questions on all things astronomy and Black Hole related.


Further Information (Links):

Event Horizon Telescope

First Image of a black hole, Poōwehi, obtained by the EHT (April 2019)

James Clerk Maxwell Telescope

Pōwehi Day proclamation
Governor Ige declares April 10th – Pōwehi Day

MKO@Home on YouTube


Background Information:

The international collaboration announced the first-ever image of a black hole, Pōwehi, by creating a virtual Earth-sized telescope at the heart of the radio galaxy Messier 87 on April 10, 2019. Supported by considerable international investment, the EHT links existing telescopes using novel systems — creating a new instrument with the highest angular resolving power that has yet been achieved.

The individual telescopes involved in the EHT collaboration are at present: the James Clerk Maxwell Telescope (JCMT), the Submillimeter Array (SMA), ALMA, APEX, the IRAM 30-meter Telescope, the IRAM NOEMA Observatory (expected 2021), the Kitt Peak Telescope (expected 2021), , the Large Millimeter Telescope (LMT),, the Submillimeter Telescope (SMT), the South Pole Telescope (SPT), and the Greenland Telescope (GLT, since 2018).

The telescopes work together through a VLBI technique. This synchronises facilities around the world and exploits the rotation of our planet to form one huge, Earth-size telescope. VLBI allows the EHT to achieve a resolution of 20 micro-arcseconds — equivalent to identifying an orange on Earth as seen by an astronaut from the Moon. The data analysis to transform raw data to an image required specific computers (or correlators), hosted by the MPIfR in Bonn and the MIT Haystack Observatory.

The EHT consortium consists of 13 stakeholder institutes; the Academia Sinica Institute of Astronomy and Astrophysics, the University of Arizona, the University of Chicago, the East Asian Observatory, Goethe-Universität Frankfurt, Institut de Radioastronomie Millimétrique, Large Millimeter Telescope, Max-Planck-Institut für Radioastronomie, MIT Haystack Observatory, National Astronomical Observatory of Japan, Perimeter Institute for Theoretical Physics, Radboud University and the Smithsonian Astrophysical Observatory.


Original Paper:

J.Y. Kim, T.P. Krichbaum, A.E. Broderick, et al.: Event Horizon Telescope imaging of the archetypal blazar 3C 279 at an extreme 20 microarcsecond resolution, in: Astronomy & Astrophysics, April 2020



Dr. Jessica Dempsey
James Clerk Maxwell Telescope, East Asian Observatory
Email: j.dempsey@eaobservatory.org

Dr. Jae-Young Kim
Max-Planck-Institut für Radioastronomie, Bonn.
Fon: +49 228 525-431
E-mail: jykim@mpifr-bonn.mpg.de

Explore the universe from home with Maunakea Observatories

This article appeared in the University of Hawai’i News on April 6th: https://www.hawaii.edu/news/2020/04/06/maunakea-observatories-at-home/

In response to the interruption of hands-on science education and outreach during the COVID-19 crisis, the Maunakea Observatories (MKO) have unveiled a distance learning program, MKO@Home online. The virtual project consists of short weekly videos that feature astronomy related activities, demonstrations and interviews.

“The Maunakea Observatories recognize the severe educational difficulties that COVID-19 is creating for the community, and we are doing as much as we can to address this challenge. We are rallying all of our outreach resources and will be presenting as much content as possible during this unprecedented crisis,” said Bob McLaren, University of Hawaiʻi Institute for Astronomy interim director.

MKO@Home videos featuring scientists and educators are designed to allow K–12 students and families to explore the universe from home.

“Aunty Mimi” Fuchs from the East Asian Observatory demonstrates the scale of the solar system.

Content for the pilot program ranges from lessons on the night sky, to Pōwehi, the now-famous supermassive black hole. The cosmic wonder was given a name in ʻōlelo Hawaiʻi or Hawaiian language by UH Hilo professor Larry Kimura. The name recognizes the instrumental role that observatories on Maunakea played in the worldwide effort to capture an image of a black hole for the first time in history.

April 6–10, MKO@Home will celebrate Black Hole Week and feature demonstrations by Maunakea astronomers about the mysterious objects.

MKO@Home videos are uploaded three times a week on Mondays, Wednesdays and Fridays.

For more, go to Maunakea Observatories.

To watch all of the EAO videos on MKO@Home and more, visit our Videos page here.

Subscribe to the MKO@Home videos on the Maunakea Observatories YouTube Channel here.

COVID-19 operational update

Once again, staff at the East Asian Observatory, send our thoughts out to our community across the world and hope you and your families are well and safe.

The Governor of Hawaii has announced a ‘stay-at-home’ order for the entire State, effective from Wednesday 25th of March, through to April 30th. We hope that this order will help us here in the islands to slow and minimize the spread of the COVID-19 virus within our community. As you know, JCMT and EAO has been on operational hiatus since March 13th through to the end of March. In compliance with this order, we will be extending the hiatus until April 30th.

As we’ve mentioned before, all of our staff are now working from home, diligently and creatively, to continue to deliver you science support, data reduction assistance or anything else you need – so please continue to reach out to them.

We are committed members of this island community, and are glad we are doing what we can to help our families, friends and those most at risk in our community. Please take care of yourselves, and your families, and we thank you for your continued support.

with thanks,
Jessica on behalf of the EAO `ohana.

JCMT Semester 20B proposal submission deadline extension

Due to the significant logistical impact of the current COVID-19 pandemic on many members of the JCMT user community, the exceptional decision has been made that the semester 20B PI proposal submission deadline will be extended by two weeks, until 2020-03-31 01:00 (UTC).

Any PIs that have already submitted projects remain free to edit and resubmit them further, and new submissions will be accepted during this two-week period without penalty.

For full details on the 20B Call for proposals, and for proposal submission, please see


For any questions or concerns regarding any of the above, please feel free to contact us at helpdesk@eaobservatory.org.

JCMT Astronomer helps shed new light on black hole ejections

Dr. Alexandra Tetarenko

Maunakea astronomer, Dr. Alexandra Tetarenko, who works at the James Clerk Maxwell Telescope, has been collaborating with a research group led by Oxford’s Department of Physics which has observed a black hole ejecting material at close to the speed of light, out to some of the largest separations ever seen. These observations have allowed a deeper understanding into how black holes interact with their environment.

Dr. Tetarenko’s research uses a number of telescopes around the world, including the facilities here on Maunakea, to study transient astrophysical systems – objects that change brightness on short timescales. “The system we studied in this instance contains a dynamically confirmed black hole within our Galaxy and another star (not too dissimilar from our sun) orbiting one another. The black hole, due to its strong gravitational pull, syphons material from its companion star in a process known as accretion” says Dr. Tetarenko.

Lead author, Joe Bright, a PhD student at Oxford University’s Department of Physics explains: “Most importantly to this work is the fact that the material is not all lost into the black hole. Outflows are launched away from the black hole at extreme velocities – almost the speed of light – and can be observed with radio telescopes.

“Our research group, consisting of many international astronomers, led an extensive observing campaign on this particular system, known as MAXI J1820+070, after it went into a bright outburst in the summer of 2018. This in itself was remarkable as this type of transient astrophysical system mostly accretes a very small amount of material and so can’t be seen; they do however occasionally go into outburst and only then are they observable.”

A series of images of the black hole MAXI J1820+070 throughout its 2018 outburst, taken with several different radio telescopes. The solid white line marks the position of the black hole, and the dotted lines show the movement of two ejections of plasma launched during the outburst.

The observing campaign of MAXI J1820+070 used the Very Long Baseline Array (VLBA), which has an antenna located in Hawaii on the slopes of Maunakea, along with other telescopes in the UK, USA, and the newly operational MeerKAT telescope in South Africa. “With these facilities we were able to track the connection between accretion and outflows. More excitingly, we were able to observe the system launching ejections of material, and to track these ejections over a wide range of separations from the black hole” explains Dr. Tetarenko.

The group successfully continuously tracked these ejections to extreme distances from the black hole with a range of radio telescopes and the final angular separation is among the largest seen from such systems. The ejections are moving so fast that they appear to be moving faster than the speed of light – they are not, rather this is a phenomenon known as apparent superluminal motion.

Co-lead on the project, Dr. Rob Fender said “We’ve been studying these kinds of jets for over 20 years and never have we tracked them so beautifully over such a large distance. To see them so early on in the operation of a new facility like MeerKAT is fantastic, and – as is often the case – teaches us not to confidently predict what we’re going to see in the future”.

Using the series of radio observations in this study, the authors were able to better estimate how much energy is contained in these ejections using a novel method for this type of system. “Galactic black holes, such as MAXI J1820+070, are thought to be miniature versions of the supermassive black holes that are found at the centre of galaxies. The feedback from these supermassive black holes is thought to be a vital component regulating the growth of galaxies – but these systems evolve on timescales much longer than a human lifetime. Their galactic counterparts, however, evolve quickly and are therefore the perfect systems to study the feedback process and its connection to accretion” explains lead author Joe Bright.

This work is published in the journal Nature Astronomy: https://www.nature.com/articles/s41550-020-1023-5


Call for Proposals 20B

The East Asian Observatory is happy to invite PI observing proposals for semester 20B at the JCMT. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission, please see


The 20B Call for Proposals closes on the 16th of March, 2020.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

20A Large Program Open Enrollment

JCMT users are also reminded that the time-limited Open Enrollment period for approved 20A Large Programs has begun. Further details are available here.

– 20200214

Special Supplementary Call for South Korea-led Proposals — 20X (in parallel with 20A)

The proposal submission deadline for this Special 20X Supplementary Call for Proposals is February 28th, 2020.

This Call is using the “Rapid Turnaround”-style peer-review format, in which all proposals submitted for this Call shall be peer-reviewed by the proposal creator (or designated co-author) of other proposals also submitted for this Call.

The proposal peer-review deadline for this Call is March 7th, 2020.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

– 20200205

Open Enrollment Now Open

On the first of February 2019 the JCMT will allow into the JCMT queue a number of new Large Programs (alongside extension requests of existing programs). If you are interested in joining one of the new programs or programs that were approved for an extension please visit the Large Programs webpages.

Astronomers from EAO region (CN, JP, KR, TW) or partner (CA, UK) institutions are welcome to join new programs under the Open Enrollment process as well as astronomers from Vietnam, Thailand, Malaysia and Indonesian as these regions have “observer” status with the JCMT. Open Enrollment to programs approved for time during the 20A Call for Large Programs is open now and will close March 13th 2020. To sign up to join the 20A Large Programs please visit:

JCMT 20A Large Program Open Enrollment page

Open Enrollment will close March 13th 2020.

EHT Consortium meets in Hilo

The Event Horizon Telescope Consortium met in Hawai`i for the first time since the release of the first image of a Black Hole Pōwehi. The meeting took place at the Hilo Naniloa Hotel during the week of December 5th. In addition to the meeting a public talk by Dr. Ziri Younsi and Dr. Junhan was given on Friday December 6 at ‘Imiloa Astronomy Center’s planetarium.

JCMT 2019 Users Meeting underway in Taiwan

The 2019 JCMT Users Meeting is underway at ASIAA in Taiwan. If you wish to watch the talks remotely please visit the program pages. This link will also provide the pdfs of the talk being given, and pdfs of the poster presentations. EAO staff members Mark Rawlings, Sarah Graves and Alex Tetarenko are there in person throughout the meeting to answer any questions you might have about JCMT observing and data analysis.

JCMT shifts to Remote Operations

JCMT has began a new era. Starting November 1st all data obtained at the JCMT will be observed remotely from Hilo. The first night of Remote Observing was staffed by JCMT Telescope Operator Mimi Fuchs.

JCMT astronomers who obtain data on a given night will now receive an automated email to inform them of observation being taken. At that time users are welcome to “eavesdrop” on operations by joining a remote connection directly to the JCMT Remote Observing Control room (JROC) in Hilo via the link provided in the automated email.

First Light with new JCMT receiver `Ū`ū

Congratulations to both ASIAA and JCMT staff! We achieved first light with our receiver `Ū`ū on Friday, October 4th, 2019. `Ū`ū is part of the Nāmakanui instrument and works at wavelengths around 1.2mm. Our first observation was taken of CRL2688, a bright sub-mm source between a red giant and planetary nebulae.

Nāmakanui has been offered to JCMT users for single dish observing, initially at 230GHz and later at 345GHz.`Ū`ū is a dual polarization 2-sideband receiver with up to 8GHz of bandwidth (less when using ACSIS). `Ū`ū will be much faster than Rx3Am (which was retired in June 2018) for similar observations. The JCMT Heterodyne Integration Time Calculator https://proposals.eaobservatory.org/jcmt/calculator/heterodyne/ has been updated for `Ū`ū observing.



JCMT Rapid Turnaround Proposal Submissions Now Invited

JCMT Rapid Turnaround Proposal Submission Call Opens on October 1st, 2019

The East Asian Observatory is pleased to invite proposals requesting Rapid Turnaround (RT) time at the JCMT. All prospective PIs should review the JCMT eligibility requirements page prior to the preparation and submission of a proposal.

A new RT submission cycle shall begin at the start of every month and close at the start of the next month. Any proposals not yet submitted by this time will be treated as still in preparation, and can be submitted during a subsequent cycle for the same semester. RT requests are limited to a maximum of 8 hours for Band 1 – 4 time requests, but are unlimited for Band 5 time requests. The Observatory shall aim to complete successful RT proposals within six months of their formal approval, after which time they shall be removed from the observing queue (regardless of their level of completion).

All RT proposals submitted shall be peer-reviewed by the proposal creator (or designated co-author) of other proposals submitted during the same submission cycle. The proposal peer review deadlines shall normally be two weeks after the close of the regular end-of-month RT proposal submission deadlines.

By submitting an RT proposal, all proposing teams are committing themselves to providing ratings and brief written assessments of several other proposals submitted for this Call by the corresponding deadline. Any proposing team that fails to provide a full set of reviews for their assigned proposals by the corresponding review deadline shall have their own proposal removed from the review process.

The MSBs for all approved RT projects should be created as soon as possible after their corresponding monthly RT review period has completed, ideally before the end of the month following the proposal submission deadline.

For further details regarding RT proposals, please see the relevant Call for Proposals page here. Any further questions should be directed to helpdesk@eaobservatory.org.

New Hedwig users should select ‘Log in’ and create an account. A ‘Help’ facility is available in the upper right corner, and individual Help tags at many other places.

Event Horizon Telescope Collaboration Wins 2020 Breakthrough Prize in Fundamental Physics

On Thursday, September 5th, 2019, the Event Horizon Telescope Collaboration was announced the winner of the prestigious Breakthrough Prize in Fundamental Physics. The $3 million prize, also known as the “Oscars of Science”, will be shared equally with 347 scientists co-authoring any of the six papers published by EHT. JCMT staff feel truly honored to have contributed to the Event Horizon Telescope Consortium that captured the first ever image of the Black Hole, Pōwehi, and look forward to our next EHT observing run in Spring of 2020. Deputy Director of JCMT, Jessica Dempsey, will be donating her portion of the award to the A Hua He Inoa program committed to propelling Hawaiian language and traditions to the global astronomical stage.


Event Horizon Telescope Collaboration: Winner of the 2020 Breakthrough Prize in Fundamental Physics

We’re pleased to announce that this year's Breakthrough Prize in Fundamental Physics goes to the Event Horizon Telescope Collaboration. The prize recognizes the team's extraordinary achievement in producing the first photograph of the “shadow" of a black hole. The experiment involved hundreds of collaborators across 8 telescopes, 60 institutions and 20 countries. Tune in to the Breakthrough Prize ceremony on the National Geographic channel November 3. More at https://breakthroughprize.org/News/54.

Posted by Breakthrough on Thursday, September 5, 2019



Call for Proposals 20A: PI and Large Programs

JCMT Call for Semester 20A PI Programs

The East Asian Observatory is happy to invite PI observing proposals for semester 20A at the JCMT. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission, please see


The 20A Call for PI Proposals closes on the 16th of September, 2019. The Hedwig system permits the submission (and repeated re-submission) of proposals until this deadline.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places. Note that from this semester onward, Hedwig also allows a user to create copies of their preexisting proposals, in order to simplify the process of proposal re-submission.

JCMT Call for Large Programs (III)

The East Asian Observatory is also happy to invite applications for the third Call for JCMT Large Programs. At this time, 4,800 hours will be available for Large Programs up until the end of the 22B semester. Submissions will be accepted until the September 16th deadline. Please see here for more details. The proposal handling system, Hedwig, is available here.

For further details regarding current or previous Calls for Proposals, please see the proposal web pages.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions about either of the above Calls for Proposals.

– 20190815

JCMT resumes night time operations

Dear JCMT Community,

We are pleased to announce that we have resumed night time operations at the JCMT. Our first night on sky way Sunday August 11th where we did a functional check out of our systems, took some engineering observations, followed by observations for the Large Program Queue. Our beloved Jim Hoge was the telescope operator in charge and was very happy to be back collecting precious scientific data. Currently we are limited to SCUBA-2 observing only whilst HARP undergoes engineering work. We hope to have it back on sky in September.

We would like to say a big thank you to our JCMT community for their support, patience and understanding. As always the safety of everyone on the mountain is of paramount importance to us.


Nāmakanui Has Arrived in Hilo!

Nāmakanui (pronounced “Naaah-mah-kah-noo-ee”), our newest addition to the JCMT instrumentation suite, arrived in Hilo last week and is now out of the box and being tested in Hilo by staff. The Hawaiian name “Nāmakanui” means “Big-Eyes” and it refers to a type of fish found in and around the islands.

When it is fully commissioned, Nāmakanui will be able to look at the sky using one of three receivers. Each receiver carries the name of a different type of Nāmakanui fish: `Ala`ihi (pronounced “ah-la-ee-hee”; 86 GHz), `U`u (pronounced “oo-oo”; 230 GHz), and `Āweoweo (pronounced “aaah-vay-oh-vay-oh”; 345 GHz). `U`u is the first receiver that will be commissioned.

This instrument will be critical for helping take the next Pōwehi image (the Hawaiian name for the Black Hole image at the centre of M87), hooking into the Event Horizon Telescope network. Additionally, it will be capable of delivering a wide range of fantastic science from studying the earliest stages of star formation and the late stages of stellar mass loss to investigating the gas dynamics of galaxies.  It takes 12 hours to cool down Nāmakanui to its operational temperature (4K) and so far the testing is going very well!

This instrument was built by a team at ASIAA (Taiwan) and is on loan the to the JCMT as a spare for the Greenland Telescope. We are very grateful for the opportunity to collect exciting data with this next-generation instrument!
To learn more about this instrument click here: https://buff.ly/2Zkv1lW


JCMT Operations Temporarily Suspended

Dear JCMT Community,

This week, the pending start of the construction of the Thirty Meter Telescope has sparked a protest which has blocked access to Maunakea for all traffic. Yesterday afternoon, the directors of the existing observatories made the joint decision to remove all personnel from their telescope facilities at the summit to guarantee the safety of their staff – the institutions’ top priority. Without guaranteed, reliable access to the telescopes, the Maunakea Observatories have suspended all summit activities (including remote operations) for the time being.

The safety of everyone on the mountain, MKO staff, law enforcement, and protestors is of paramount importance to us. We have voluntarily decided to remove our staff. This is not a decision we came to lightly, but want to emphasize the importance of safety for all staff and facilities.

We are truly grateful to the law enforcement offices who have been working around the clock to ensure the safety of everyone on Maunakea. The safety of our personnel – and of everyone on the mountain – remains our top priority.

We look forward to returning to normal operations as soon as the situation allows.

From the JCMT Team, Aloha and thank you for understanding.

Remote Operations

East Asian Observatory is excited to announce that JCMT will be moving to fully remote operation from November 1st, 2019. From that date forward, JCMT will not require visiting observers to staff observing runs at the telescope.

The close collaboration between our user community and the Observatory is one of the greatest strengths of the JCMT. EAO will continue to enhance this relationship in the new era of fully remote operations via visiting young student programs, online real-time access to nighttime observing, and a range of other initiatives. We welcome your ideas and need your contributions to continue to produce the high impact science that we are all so proud of at JCMT. EAO welcomes short- and long-term visits to the Observatory to meet and collaborate with staff and learn about data reduction and analysis techniques. Astronomers wanting to work with our upcoming new instrument suite or utilize complex observing modes (e.g. VLBI) will also be encouraged to visit the JCMT to assist with commissioning efforts to ensure high quality science is produced.

In addition to welcoming visiting astronomers, the EAO will continue to host the JCMT Users Meeting yearly (this year in Taiwan) and will continue to send observatory staff to our regions when requested for workshops.

Remote operation is not a new concept for the JCMT, having been done in the past on occasion, and routinely via Extended Observing shifts since 2013/2014 (for more see the January 2014 Newsletter). Progress towards fully remote observing has been moving at an excellent pace. The observatory’s engineering team has been working hard this summer to overhaul and upgrade JCMT systems – including an overhaul of the roof and door hydraulics – and this work is on schedule to be complete well in advance of our planned switchover in November.

The Observatory appreciates your support and understanding as we advance into to this exciting new era for JCMT science. If you have any questions or concerns, please email our helpdesk@eaobservatory.org.

Image Credit: William Montgomerie

As a reminder, to get up-to-date information about the JCMT please send an e-mail to jcmt_users+subscribe@eaobservatory.org.

Hawaiʻi Astronomer Wins Canadian Award

Hawai`i Astronomer Wins Canadian Award

Hawaiʻi attracts the world’s top talent in astronomy due to Maunakea being one of the leading sites to study the universe. Today, EAO/JCMT astronomer Dr. Alex Tetarenko was awarded the 2019 J. S. Plaskett Medal by the Canadian Astronomical Society (CASCA).

Dr. Tetarenko was awarded the medal for her doctoral thesis on the physics of relativistic jets in X-ray binaries, as revealed by radio, millimeter (mm), and sub-millimeter (sub-mm) observations. Dr. Tetarenko obtained her PhD at the University of Alberta, and is now a 2018 East Asian Observatory Fellow working in Hilo, Hawaiʻi.

Dr. Tetarenko was awarded the medal for her exceptional skills both as an observer and in her insightful physical interpretation of complex observational data. Specifically, she is a leading expert in mm/sub-mm observations of black hole X-ray binaries. Recently, the journal Nature published  Dr. Tetarenko’s paper on  the rapidly spinning black hole in the Galactic binary system V404 Cygni. Dr. Tetarenko and her team used the Very Long Baseline Array (part of which is located on Maunakea) to observe this stellar mass black hole eject rapidly rotating high-speed clouds of plasma (known as jets), which are thought to be driven by the effects of Einstein’s theory of general relativity.

Dr. Alex Tetarenko with the J.S. Plaskett Medal, Awarded by the Canadian Astronomical Society at the 2019 annual general meeting in Montreal, QC, Canada. Photo Credit: Steve Mairs

On being awarded the 2019 J. S. Plaskett Medal, Dr. Tetarenko said “I am honored and humbled by the award, and grateful to be included among the list of awesome Canadian astronomers who have come before me”. On living and working in Hawaiʻi, Dr. Tetarenko said “I absolutely love being based in Hawaiʻi. Not only is Hawaiʻi one of the foremost centres of astronomy in the world, where I have access to world class telescopes and all the support and resources I need for my research, but it is also a beautiful island with a rich culture, that provides a very welcome escape from harsh Canadian winters.

Media Contacts:

  • Alex Tetarenko
  • James Clerk Maxwell Telescope
  • 1-808-969-6519
  • a.tetarenko@eaobservatory.org


  • Jessica Dempsey
  • James Clerk Maxwell Telescope
  • 1-808-969-6512
  • j.dempsey@eaobservatory.org

Additional Links:

About East Asian Observatory/James Clerk Maxwell Telescope
The EAO (East Asian Observatory) is formed  by EACOA (East Asian Core Observatories Association) for the purpose of pursuing joint projects in astronomy within the East Asian region. The EAO is chartered as a non-profit Hawai`i corporation. Its first task is to assume the operation of the James Clerk Maxwell Submillimetre Telescope (JCMT) on the summit of Maunakea, Hawai`i. Pursuant to an agreement with the University of Hawai`i, the EAO also provides engineering and IT support to the UKIRT Observatory (UKIRT). The JCMT is run by the non-profit organization the East Asian Observatory.


Special Supplementary Call for South Korea-led Proposals – 19B

The East Asian Observatory invites JCMT observing proposals with Principal Investigators (PIs) affiliated with a South Korean institution only for a special 19B Supplementary Call for Proposals. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission, please see here.

The proposal submission deadline for this Special 19B Supplementary Call for Proposals is July 8th, 2019.

This Call is using a new “Rapid Turnaround”-style peer-review format, in which all proposals submitted for this Call shall be peer-reviewed by the proposal creator (or designated co-author) of other proposals also submitted for this Call.

The proposal peer-review deadline for this Call is July 22nd, 2019.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

– 20190215

International Women’s Day 2019

The Women of Maunakea once again met to celebrate their achievements and seek more advancements at this years International Women’s Day event held on March 3rd at Imiloa Astronomy Centre, Hilo, Hawai`i.

At the event our organization introduced a new equality challenge for the entire astronomy community on Hawai‘i Island, pledging to support equality and diversity within their ranks. Jessica Dempsey, Deputy Director of EAO/JCMT stated that

“Living in one of the most diverse states in the country, host to the most female astronomers in the world, we are uniquely positioned to serve as a model of progress toward gender equity and diversity in the workplace”

Jessica seeks to get to gender parity within the ranks of the organization by 2024 .

The event has been followed with a number of social media posts by the Maunakea Observatories within Hawai`i in support of International Women’s Day 2019 held on March 8th (#IWD2019).

Big Island Now – Maunakea Observatories Launches Equity Challenge on International Women’s Day

Big Island Video News – International Women’s Day Mixer At Imiloa

Call for Proposals 19B

The East Asian Observatory is happy to invite PI observing proposals for semester 19B at the JCMT. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission, please see


The 19B Call for Proposals closes on the 15th of March, 2019.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

– 20190215

JCMT Transient Survey Team Observes Record-Breaking Flare

On November 26th, 2016, the JCMT Transient Survey Team observed what is estimated to be the most luminous known flare associated with a young stellar object. It is also the first coronal flare discovered at submillimetre wavelengths. The brief flash of light occurred in the direction of a binary system of forming stars known as “JW 566” in the Orion Nebula and it carried ten billion times the amount of energy of the solar flares observed around the Sun.

Left: The Orion Nebula as seen by SCUBA-2 at 850 microns. Right: Two images of
the field surrounded by the green square taken 6 days apart. Small rectangles/triangles show the
positions of known young stars found by other telescopes. On November 20th, 2016, there was
no signal. On November 26th, 2016, the flare was observed while it was already dimming from
its (unseen) maximum brightness.

The flare was discovered by JCMT support astronomer Dr. Steve Mairs using advanced image analysis techniques that had been developed by the Transient Survey team over the past 2 years. The SCUBA-2 observations lasted approximately 30 minutes over which time  the flare faded to half of the brightness measured at the beginning of the scan, indicating the event was short-lived. The flare is thought to be caused by an intense magnetic field re-connection event that energised charged particles to emit gyrosynchrotron/synchrotron radiation.

Press Release: Sky and Telescope, Hawai’i Tribune Herald, Big Island News

Publication: ArXiv, ApJ

The JCMT Transient Survey Team

The JCMT Transient Survey team is an international collaboration of 80 astronomers led by Dr. Gregory Herczeg of Peking (Kavli Institute for Astronomy and Astrophysics) and Dr. Doug Johnstone (National Research Council of Canada). The team has been monitoring 8 star-forming regions in the Milky Way with a monthly cadence since December, 2015. The survey will continue through January, 2020.

The Brightest Quasar in the Early Universe

Observations obtained by the JCMT helped uncover the Brightest Quasar in the Early Universe!

The light from Quasar J043947.08+163415.7 is gravitationally lensed by a dim Galaxy in the foreground, allowing Fan et al. (2019, APJL: 870, 11) to get a good look at this active galactic nucleus at a redshift of z = 6.51 (A distance of ~12.8 Billion Light years!). As the authors note, “This is the first such object detected at the epoch of reionization, and the brightest quasar yet known at z > 5”.

The JCMT is instrumental in observing distant star-forming galaxies. These galaxies have high concentrations of dust that reprocess the starlight such that it is emitted at infrared wavelengths. The light is then redshifted due to the expansion of the universe into the submillimetre regime. The star formation rate is estimated to be 10,000 times higher than that of our own Galaxy, the Milky Way.

Press Release:

Astronomers uncover the brightest quasar in the early universe


The Discovery of a Gravitationally Lensed Quasar at z = 6.51

An artist’s rendering of a distance quasar (Credit: ESO/M. Kornmesserhttp://www.eso.org/public/images/eso1122a/)

A bit of history…

The name “Quasar” is a shortened version of the original designation scientists gave to a mysterious signal we didn’t have a scientific interpretation for: a “quasi-stellar radio source” discovered in 1963 by Maarten Schmidt.

Over decades of intensive studies, astronomers have been able to determine that these mysterious signals were coming from intense bursts of light in the hearts of galaxies far, far away.

Most (maybe all!) galaxies contain a supermassive black hole millions to billions times the mass of our Sun. In some of these galaxies, infalling material gets too close to the black hole and it heats up to millions of degrees, exploding outward in a massive release of energy!

We can detect those signals, which we now affectionately call Quasars, at submillimetre wavelengths with the JCMT.

Congratulations to Dr. Xiaohui Fan and his co-authors !

ABC Film Crew Visit JCMT

This past week the JCMT was host to a film crew from the Australian Broadcasting Corporation, based in Sydney. The crew were visiting Hawaii as part of a science television program  called Catalyst. Specifically they were out visiting the JCMT as part of a program about the Black Hole at the centre of our Milky Way, and how JCMT, along telescopes from around the world are coming together to form the Event Horizon Telescope – looking to take an image of the shadow around the Black Hole at the centre of our Galaxy.


Maunakea Wonders Teachers Workshop

The third Maunakea Wonders Teacher Workshop began on October 17th at the University of Hawai’i’s Department of Education in Hilo. Throughout the second half of October, we have the incredible opportunity to share fun astronomy activities and resources with the future teachers of Hawai’i. Despite the frigid weather, this included on-site tours of the JCMT and UKIRT where we had a blast talking about the different functions of each telescope on the mountain. We are looking forward to more fun and excitement on campus on October 31st – Mahalo nui loa to this vibrant group of educators!


Maunakea Gender Equity and Diversity Survey 2018 Report

In July 2018, the Maunakea Gender Equity and Diversity Committee distributed a survey to the staff at the Maunakea astronomical organizations. The survey was intended to invite opinion on the current state of equity and diversity in the Maunakea astronomy community and seed conversation and ideas for enhancing diversity and inclusion in our organizations across our islands.

The report on the results of the survey is here:

Maunakea Gender Equity and Diversity Survey 2018 Report

and the Appendix A, listing the survey questions, is provided for reference:

Gender Equity and Diversity Survey questions

The first results are presented by Jessica Dempsey at the Maunakea Users’ Meeting on October 4th, 2018. A PDF of the talk is linked here for convenience. For usage or distribution of these data, please contact Jessica Dempsey: j.dempsey “at” eaobservatory.org.

Photo by Oro Whitley

– 20181004


Call for Proposals 19A

The East Asian Observatory is happy to invite PI observing proposals for semester 19A at the JCMT. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission please see


The 19A Call for Proposals closes on the 15th of September, 2018.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

– 20180815

Mahalo to Mailani Neal!

The East Asian Observatory wishes to extend a big mahalo to our summer intern Mailani Neal for her excellent work tracking temperature changes across the JCMT’s dish!

We are grateful for all her hard work and we wish her all the best as she enters her final year at Rensselaer Polytechnic Institute in New York!

This gif shows an example of the telescope’s changing temperature over one night in June, 2018:

This analysis is important for understanding calibration observations and the effect of the weather on all the data we collect.

Mahalo, Mailani!

– 20180807

RxA3m Retires

     We are only as good as the instruments we have. With this sentiment in mind, we make way for the next generation of instruments as we retire one of our long-serving heterodyne receivers, RxA3. 

RxA3m in the receiver cabin at JCMT

     RxA3 (http://www.eaobservatory.org/jcmt/instrumentation/heterodyne/rxa/) has been a stable source of great science for the JCMT since it was built by the Herzberg Institute of Astrophysics and delivered in 1998. It has served our JCMT user community well and the data collected from RxA3 will be utilized still for years to come. 

The GLT receiver installed at the JCMT when it was being tested in August 2017.

      With the retirement of RxA3, JCMT prepares for it’s replacement to arrive in January 2019 and hopes to be on sky by April 2019 in time for the next Event Horizon Telescope observing run. The replacement will be a three-receiver cryostat identical to that installed on the Greenland Telescope (GLT), and is estimated to be able to complete observations in approximately 1/4 of the time required by RxA3.

2018 OT update

We are always striving to do better at the JCMT and that means we often update our software. One software update that uses should be aware of is a new version of the JCMT Observing Tool.

It is particularly important to note that the OT version used for all semester 18B MSB preparation must be 20180516 (or newer). This may be checked via the OT start-up splash screen and also via the “Help -> About” menu option.

– 20180525

SMU Removal

Check out our hardworking staff carefully removing the Secondary Mirror Unit (SMU). JCMT is currently closed (2.5 weeks in May 2018) as the SMU undergoes some important maintenance. The basics of the work being done:
1. Chopper performance and XYZ tables measurements
2. Remove the chopper and service the SMU tables (strip down, clean, lubricate, change belts)
3. Reassemble SMU tables, reattach chopper and service (balance, vibrators, flex pivots, LVDTs, stingers)
4. Finalize and implement new zero points, rollover points, and limits
**Many thanks to our TSS Kevin Silva for putting together this awesome timelapse compilation.**


Call for Proposals 18B

The East Asian Observatory is happy to invite PI observing proposals for semester 18B at JCMT. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission please see


The 18B Call for Proposals closes on the 15th of March, 2018.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

– 20180214

Membrane back on!

January 10, 2018  The JCMT’s protective membrane is back in place after our month of commissioning without it. Now we can go back to observing in reasonable wind and during the daytime!



Engineering shutdown – May 2018

From time to time the JCMT is closed due to major maintenance work. The next scheduled closure of the JCMT will occur from April 30th 2018 to mid May 2018. During this time the Gore-Tex membrane windblind will be removed to provide access to the Secondary Mirror Unit for maintenance work. As the telescope will be unavailable for science during this time the SCUBA-2 Gas Handling System will also be worked on. SCUBA-2 will be warm during this period and should back to operational temperature/available for science use by the end of May.

– 20171201

Membrane removal scheduled for December 2017

The staff at EAO would like to announce that we are planning an approximately month-long observing campaign without our iconic Gore-Tex membrane windblind.

The removal of the membrane is due to the high demand for sub-mm polarimetry. Currently the instrument POL-2 is commissioned and working beautifully at 0.85mm, with some fantastic science results. POL-2 science at 0.85 mm has been so successful that we are keen to see if operating without the membrane – which can limit the throughput and increase instrumental polarization – we can commission POL-2 at 0.45 mm.

Observing without the membrane is not our normal mode of operation and the telescope will have additional operational limitations during this time. The JCMT will not take daytime observations and the operational wind limits will be reduced.

We expect to remove the membrane early in December and thank the JCMT astronomical community for their support.

– 20171122

JCMT OMP Database Migration Complete

The migration of our OMP database system is now complete.

Principal Investigators/Co-Investigators on current JCMT programs (17B PI programs, Urgent queue programs, and the Large Programs) should again be able to retrieve recently-acquired data for their program from either the program’s OMP page or directly from the JCMT data archive at the CADC. As usual, the former method requires that the user’s OMP and CADC accounts are first linked (please see here for more details).

Any PIs/Co-Is that continue to encounter problems should consult their designated Friend of Project (FoP).

– 20171120

JCMT Data Retrieval During Database Migration Period

We are currently migrating our OMP database system, a process that is expected to take up to 4 weeks. During this period, any Principal Investigators/Co-Investigators on current JCMT programs (17B PI, Urgent queue projects, and the Large Programs) wishing to retrieve recently-acquired data for their projects should download it directly from the JCMT data archive at the CADC, rather than from the project’s OMP pages.

– 20171102

Update: This database migration process has now been completed (see above for further details).

– 20171120

Call for Proposals 18A

The East Asian Observatory is happy to invite PI observing proposals for semester 18A at JCMT. Proposal submission is via the JCMT proposal handling system, Hedwig. For full details, and for proposal submission please see


The 18A Call for Proposals closes on the 15th of September, 2017.

If this is your first time using Hedwig, you should ‘Log in’ and generate an account. There is a Hedwig ‘Help’ facility at the upper right corner of each page, and individual Help tags in many other places.

Please contact us at helpdesk@eaobservatory.org if you have remaining questions.

– 20170815

Green Land Telescope Receiver testing progressing well at the JCMT

The Greenland Telescope (GLT) is a novel project; taking a 12-meter radio antenna – prototype for the Atacama Large Millimeter/Submillimeter Array (ALMA) project from Chile, and relocating this telescope to Greenland.

By repurposing this telescope astronomers can take advantage of the near-ideal conditions of the Arctic to study the Universe at specific radio frequencies. Whilst the telescope is being commissioned the initial receiver that will be used at the GLT is being tested at the JCMT in Hawaii. Last week the alignment of the instrument was performed this morning using the Sun as a source – and at the JCMT the first astronomical source for this instrument!

form more information visit: www.asiaa.sinica.edu.tw/project/vlbi.php and www.cfa.harvard.edu/greenland12m.

The GLT receiver installed inside the receiver cabin on the JCMT.

The inside of the GLT receiver

Delivery of the GLT receiver to JCMT

– 20170814

EAO Mid Term Review Committee meet in Hilo

The EAO Mid Term Review committee are meeting this week in Hilo to discuss the future of the JCMT. When the East Asian Observatory took over operation of the JCMT back in 2015 it was for an initial 5 years. Since that time we have had 5 semesters of great science. We have successfully completed three large programs (S2COSMOS, SCOPE, MALATANG). We have uncovered new star-forming events in the sub-mm. We have discovered stellar mass black holes. Our EAO regions have gained access to both Subaru and SMA. Recently we welcomed Vietnam as an observing partner in the JCMT. So much to celebrate!

– 20170727

EACOA Fellow, Tie Liu, welcomed to EAO Hilo

EACOA Fellow Dr Tie Liu is the first EACOA Fellow to come to work at the EAO office in Hilo, Hawaii from KASI.

Tie Liu’s main research interest is high-mass star formation and molecular clouds. Tie is the head of a large consortium undertaking the SCOPE, SCUBA-2 Continuum Observations of Pre-protostellar Evolution, program studying Planck cold clumps at JCMT. This program is now (as of July 2017) complete after 300 hours of SCUBA-2 time over the past year and a half.

Tie is now turning the focus of this study to follow-up observations with JCMT (e.g. POL-2) as well as many other telescopes (e.g., ALMA, SMA, NRO 45-m, KVN, FAST 500m …).

The Staff at EAO are pleased to welcome Tie Liu into the scientific division and hope many more astronomers decide to visit JCMT in the future as long term visitors, to engage directly with JCMT staff.

– 20170724


Astronomers from the East Asian Observatory/JCMT are in Taipei, Taiwan this week for the Asia Pacific Meeting of the International Astronomical Union (APRIM). If you are there please pop by our booth and say hello!

Maunakea Wonders – Teacher workshop success

For two days at the end of June EAO/JCMT hosted its first “Maunakea Wonders Teacher Workshop” primarily aimed at newly qualified teachers here on the island of Hawai’i. One day was spent learning about the cultural, environmental and astronomical role Maunakea plays combined with a trip to visit the CFHT (Canada France Hawai’i Telescope), and the JCMT. The second day was spent in the classroom discovering what Hawaii more about astronomy on the big island and the resources available to the community, teachers and students in Hawaii.

The workshop was kindly supported by MKAOC/CFHT and the University of Hawai’i Hilo’s School of Education.

First day of the Maunakea Wonders Teacher workshop included a trip to the Canada France Hawaii Telescope and then to JCMT.

Discovering cosmic distances

Discovering Teaching opportunities in Hawaii – with Gemini’s Starlab.

– 20170703

AstroDay 2017

EAO/JCMT staff once again volunteered their time to spend the day connecting with the community at the annual Hilo AstroDay. This year we explored the concept of magnetism and polarization in space.

For more about AstroDay please see:

A summary of the cryogenic work on SCUBA-2 this past winter

SCUBA-2 has been back on the sky for the past month producing excellent data, following both planned engineering down time to work on the instrument cryogenics and unplanned – to fix a vacuum leak.

The end of 2016 was a busy time for the EAO ETIS (Engineering, Technical Information Systems) staff. From the middle of the 2016 we were aware of a change in performance of one of the (two) pulse tube coolers (PTC) that cools the SCUBA-2 inner radiation shields and internal mirrors to below 4K. We were able to continue to use SCUBA-2 without any impact on the quality of the data, while we planned the major task of taking the 3 tonne instrument off the antenna and replacing both of the instrument PTC cold heads with new remote motor models.

The dilution fridge mixture was removed and the warm-up started on October 5th. SCUBA-2 was back on the sky with new PTCs and was operational by November 18th, 1 week ahead of schedule. However, during the subsequent cooldown, the cryostat vacuum was found not to be as good as expected.

Later in December, when we temporarily warmed-up (to 4K) to replace a small pump in the dilution refrigerator (DR) gas handling system – a regular procedure, the poor vacuum became a serious issue. Additional problems with pumps in the GHS and too high a pressure in the DR still prevented cooling below 1K. This is well above the operating temperature of the TES detectors.

The only course was to warm the instrument to ambient temperature and to then carry out extensive leak checking of the cryostat. A leak was found that we could fix. However, on detailed inspection, we discovered that the O-ring between the feedthrough and the top plate of the DR insert was cracked and would fail soon if we did not replace it.

Two weeks of skill and persistence was required to replace this O-ring to enable SCUBA-2 to be yet-again pumped, leak checked and cooled prior to the end of January. With the vacuum leak fixed, the cause of the second issue with the GHS that prevented cooling below 1K became apparent. This issue was caused by a particle filter on the input of the pump. After removing the offending filter SCUBA-2 was operational by February 5th.

The loss of an additional 6 weeks of observing with SCUBA-2 impacted our users. However, by catching the failing O-ring before a total loss of vacuum, we avoided the potential for more serious consequences to the instrument and a bigger disruption of the observing schedule. An extended period of good stable weather in recent weeks has allowed some of the affected programs to makeup for the missed nights.

In addition to the cryogenic work, new improved thermal blocking filters have been installed between the instrument window and the band defining filters for the detector arrays. We are now investigating the change in optical power on the detector arrays, to see if this has modified the stray light environment within the 4K box and improved SCUBA-2’s performance.

Jamie Cookson works on the repair of SCUBA-2.

– 20170407

Blue skies for Venus observations

Over the past two weekends the JCMT has been open and observing during the day. These daytime observations are needed to observe the middle atmosphere (altitude 70-110 km) of Venus.

The aim is to better understand atmospheric physics and chemistry. The way to advance understanding of fundamental atmospheric physics and chemistry in general is to study the atmospheres of individual planets – specifically in this case Venus!

The JCMT is used for this study because sub-millimeter spectroscopy is uniquely powerful for investigations of this altitude range on Venus. JCMT’s location on Maunakea, its ability to safely point arbitrarily close to the sun, and its observation flexibility (capability to modify observing strategies in as little as 5 minutes, during the observations) make it uniquely well-suited to Venus research.

Here is a video of the sky above the EAO office in Hilo – can you spot Venus? If you want to see what the weather is like on Maunakea click here. For a link to the EAO Hilo office weather click here.


Electronics Engineer job opening

We are currently recruiting for an Electronic Engineer to join the EAO/JCMT  Engineering Group. This group ensures that the telescopes and associated instruments are at a high level of operational readiness at all times. They apply technical knowledge in support of the testing, modification, maintenance, repair, and upgrading of EAO mechanical, electronic and electrical systems.

CLOSING DATE: March 24, 2017

For more information visit the EAO Jobs homepage.

– 2017/02/24

JCMT 2017 Users Meeting – see you again next year!

The 2017 JCMT Users meeting was held in Nanjing, China. The two day meeting was held on Monday, 13th and Tuesday 14th of February. An additional 1 half-day data reduction workshop was held immediately after the meeting on Wednesday 15th of February. The meeting was well attended and all talks are now available online here. We hope you have a good productive 2017 and hope to see you at our JCMT 2018 Users meeting in South Korea next January.

– 2017/02/21

Call for proposals 17B and Large Programs (II)

The East Asian Observatory is happy to invite PI observing proposals for semester 17B at JCMT (for details see here). Semester 17B runs from 01 August 2017 to 31 January 2018.

In addition the East Asian Observatory is happy to accept proposals for Large Programs – running from 01 August 2017 to 31 January 2019. More details about the Large Programs (II) call can be found here.

You can reach the proposal handling system, Hedwig,  and find complete details of this Call at:


Any further questions should be directed to our help desk: helpdesk@eaobservatory.org

If this is your first visit to Hedwig, you should go to ‘Log in’ and generate an account. There is a ‘Help’ facility at the upper right corner, and individual Help tags at many other places.

The 17B Call and Large Program (II) call for Proposals closes on the 15th of March 2017.

– 2017/02/13

17B semester Call at the Subaru Telescope is now open

The East Asian Observatory is pleased to partner with the Subaru Telescope to enable astronomers  from an East Asian participant region to have access to Subaru time. The East Asian Observatory proposals are considered by the Subaru scientific panel alongside regular Subaru proposals, with a guaranteed award of time of a total of 3 nights of observing in the semester.

The 17B semester Call at the Subaru Telescope is now open, click here for more details.

– 2017/02/08

Support Astronomer job opening

The EAO/JCMT is currently seeking an astronomer to join its team of support scientists. Duties include: Assists visiting astronomers in obtaining high-quality observational data; provides technical, scientific, and logistical support to astronomers before, during, and after their observing runs, and assists with their data analysis. Performs general and specific support of the telescope operations and/or instruments and their development. Undertakes a program of astronomical research, which may or may not be related to using the James Clerk Maxwell Telescope (JCMT).

CLOSING DATE: February 28, 2017

For more information visit the EAO Jobs homepage.

– 2017/02/02

Announcing the JCMT Large Programs (II)

The East Asian Observatory is pleased to provide an early announcement of the second Call for JCMT Large Programs. This information is being provided ahead of the opening of the Call in order for current and new teams to pursue discussion and planning. Submissions will be accepted from February 15th up until the March 15th deadline. This will coincide with the 17B PI Call.

For more information please visit:

To help cultivate ideas discussions on potential new JCMT Large Programs EAO have provided a wiki for interested JCMT users:

Please also be reminded that the 2017 JCMT Users meeting will be held February 13th and 14th in Nanjing, China. For more details on the Users meeting please visit:

– 2016/11/15

JCMT holds reduction workshop in Shanghai

At the start of October the JCMT held a Data Reduction workshop for JCMT astronomers. The workshop was held at the Shanghai Astronomical Observatory in China. Over 20 astronomers attended with a variety of backgrounds. The material presented at the workshop can be found here. Information on past workshops can be found here. If you are interested in having JCMT staff visit your institution for such an event please contact helpdesk@eaobservatory.org.

Participants at the JCMT reduction workshop, China, October 2016.

Participants at the JCMT reduction workshop, China, October 2016.

– 2016/10/25

Users Meeting – Nanjing 2017


Dear JCMT users

You are invited to attend the second EAO JCMT Users Meeting. This 2017 JCMT Users meeting will be held in Nanjing, China. The two day meeting will be held on Monday, 13th and Tuesday 14th of February. An additional 1 half-day data reduction workshop will be held immediately after the meeting on Wednesday 15th of February.

To register for the 2017 Users Meeting please use the online registration form.

Note: If you cannot access the registration form (which is a Google document), then please use this text form and email to jcmt_um_2017 “at” eaobservatory.org.

Note: All participants coming from outside of mainland China will likely require a visa. Therefore to  request a letter of invitation to attend this meeting please email:  jcmt_um_2017 “at” eaobservatory.org This process can be lengthy. You are encouraged to request this invitation letter and begin the visa application process as soon as possible.

For more information visit: www.eaobservatory.org/jcmt/science/nanjing2017/

– 2016/09/13

JCMT workshop, Shanghai, October 16th 2016

The JCMT would like to announce that the Shanghai Astronomical Observatory will hold 1-day workshop on JCMT data reductions and analysis on Oct. 16 at SHAO in Shanghai. JCMT staff, Dr. Harriet Parsons and Dr. Mark Rawlings, will give these tutorials.  The agenda can be found below.

This workshop is scheduled before JINGLE team meeting in Shanghai (Oct. 17-18) and MALATANG team meeting in Nanjing (Oct. 19-21) as a united conference. We aim to open this tutorial to all interested researchers and students, and high priority will be given to members of JINGLE, MALATANG and other JCMT large programs due to space limitation.  If you are interested to attend, please contact Ting Xiao (xiaoting@shao.ac.cn) as soon as possible to help us get a rough head account.

Agenda for the workshop on Oct. 16:

Morning session:

  • introduction to STARLINK
  • introduction to HARP and RxA3m
  • Heterodyne beginner
  • Heterodyne advanced

Afternoon session:

  • introduction to SCUBA-2
  • SCUBA-2 basic
  • SCUBA-2 advanced

In addition if requested we could cover any of the following (time permitting):

  • Hedwig session – Proposal submission to the JCMT
  • JCMTOT – how to submit JCMT project MSBs
  • POL-2 introduction and basic data reduction in an extended session
  • General JCMT project support for existing users


If you are interested in any additional topics listed above, please inform us in the email.

– 2016/09/09

Call for Proposals 17A

The East Asian Observatory is happy to invite PI observing proposals for semester 17A at JCMT (for details see here).

Semester 17A runs from 01 February 2017 to 31 July 2017. You can reach the proposal handling system, Hedwig,  and find complete details of this Call at:


Any further questions should be directed to our helpdesk:


If this is your first visit to Hedwig, you should go to ‘Log in’ and generate an account. There is a ‘Help’ facility at the upper right corner, and individual Help tags at many other places.

The 17A Call for Proposals closes on the 15th of September 2016.

NEW: The East Asian Observatory invites requests for Urgent Observing at any time – and you can now submit these request via a special Call in our Hedwig proposal system. You can find details here.

Constraints and guidance on applicant eligibility, the available instrumentation, the required content of the proposal, and other aspects of the proposal are as described in the Call for Proposals for the current semester – except as itemized below.

Urgent Requests should clearly describe the following:
1. The urgency for the observations, and why a response to the regular, semi-annual Call for Proposals is/was inappropriate.
2. The time span over which observations may be made or the specific times at which they must be made.
3. The timescale for analysis of resulting data and for publication thereof; which ought to be proportionately urgent . . .

The above information should appear in the Scientific Justifications section of the proposal; itemized as above, please. If approved, proposals will be graded with respect to the approved projects in the current semester and executed via JCMT’s Flexible Observing scheme.

– 2016/08/15

Face-to- face workshop for “SAMPLING-TOP- SCOPE”, December 14-16, Beijing -1 st announcement

The Planck satellite has discovered more than ten thousand Galactic cold clumps, the so-called “Planck Galactic Cold Clumps” (PGCCs). The PGCC catalog, covering the whole sky, hence probes wildly different environments, and represents a real goldmine for investigations of the early phases of star formation. After the successful start of the pioneer survey with the PMO 14-m telescope, we are conducting a joint survey (“SAMPLING-TOP- SCOPE”) towards 1000-2000 PGCCs with the SMT 10-m, TRAO 14-m, and JCMT 15-m telescopes. “SAMPLING” (SMT “All-sky” Mapping of PLanck Interstellar Nebulae in the Galaxy) is an ESO public survey inJ=2-1 12CO/13CO emission using the SMT 10-m telescope. “TOP” (TRAO Observations of Planck cold clumps) aims at an unbiased J=1-0 12CO/13CO survey of 2000 Planck Galactic Cold Clumps with the Taeduk Radio Astronomy Observatory 14-meter telescope. “SCOPE” (SCUBA-2 Continuum Observations of Pre-protostellar Evolution) is a legacy survey using SCUBA-2 at the James Clerk Maxwell Telescope (JCMT) of the East Asia Observatory (EAO) to survey 1000 Planck galactic cold clumps at 850 micron. We are also actively developing follow-up observations towards the SCUBA-2 cores detected in “SCOPE” with other ground-based telescopes (e.g. KVN 21-m, NRO 45-m, Effelsberg 100-m, Arecibo 300-m, SMA, and ALMA). Through these observations, we will study how dense cores form and how star formation varies as a function of environment, the universality of filaments in the cold ISM and their roles in generating dense cores, the existence of a density threshold for dense core formation, how dust properties change in different environments, and how dust properties affect the chemical evolution of dense cores.

To promote collaborations among team members on using the survey data for science, we will hold a face-to-face workshop on Dec. 14-16 at Peking University, Beijing, China. To indicate your interest in attending the workshop, please sign your name on the following doodle page:


More details of the workshop can be found on our wiki page:


Program (preliminary)

Dec 14: registration and reception
Dec 15: talks and discussions
Dec 16: talks and discussions

SOC: Tie Liu; Mark Thompson; Sheng-Yuan Liu; Gary Fuller; Ken Tatematsu; Yuefang Wu; Di Li; James di Francesco; Kee-Tae Kim; Ke Wang; Isabelle Ristorcelli; Mika Juvela

LOC: Jie Yao; Chao Zhang; Shuxian Li; Huawei Zhang; Yuefang Wu (ywu@pku.edu.cn); Tie Liu (liutiepku@gmail.com)

– 2016/07/21

JCMT Legacy Release 1 (SCUBA-2 850µm)

The JCMT is pleased to announce that its JCMT Legacy Release 1 (SCUBA-2 850µm) data set is now publicly available. This project makes available to the community uniformly reduced observations of most public SCUBA-2 850µm observations taken before 2013-08-01, as well as coadds and emission catalogs.  Please see our web page on the JCMT-LR1 for more details.

JCMT-LR1 (September 2015: SCUBA-2 850µm)

  • Public 850µm SCUBA-2 observations taken between 2011-02-01 and 2013-08-01.
  • Gridded onto HEALPix tiles using the HPX projection.
  • All reduced using the same SMURF makemap dimmconfig ‘jsa_generic’ (included in the Starlink 2015A release)
  • Coadds of all the reduced non-pointing observations which passed Quality Assurance coadded onto a single tile.
  • Catalogues of detected (>5σ) regions of contiguous emission (extents) towards each tile.
  • Catalogues of local peaks within the extents of each tile.
  • Over 2000 hours of observing time included.
  • Search CADC with proposal ID=’JCMT-LR1′ to view the coadds and catalogues.


Call for Proposals 16A

The East Asian Observatory is happy to invite PI observing proposals for semester 16A at JCMT (for details see here).

Semester 16A runs from 01 February 2016 to 31 July 2016. We are launching this Call through a new proposal handling system: Hedwig. You can reach Hedwig and find complete details of this Call at:


At your first visit, you should go to ‘Log in’ and generate an account. We hope you will find Hedwig easy to use: there is a ‘Help’ facility at the upper right corner, and individual Help tags at many places on the proposal pages.

The 16A Call for Proposals closes on the 22nd of September, 2015.

In addition, it should be noted that we will embark on survey observing in the 16A semester – and as such, PI time is more limited than the current semester, however we still strongly encourage PI submissions as at least 800 hours of time will be available to EAO and partner region investigators. Some alterations have also been made to the PI eligibility for Canada – please see the Call for details.

New Horizons for the JCMT with the East Asian Observatory: Latest Science from the JCMT

2015 IAU Splinter Session

August 6th 6pm-8pm  

Room 312 Hawaii Convention Center

The East Asian Observatory has forged a new path for the JCMT following the successful transfer of operation to EAO in March 2015. Operations immediately resumed with an EAO Pilot Science semester initiated in late March, taking successful science with JCMT’s signature instruments, and recommencing commissioning of the additional instrument elements (Pol-2 and FTS-2) for SCUBA-2. In this special session, we will present the latest results from the JCMT Legacy Surveys, completed in early 2015. We will also show some of the recent results from Pilot Science, and discuss the plans EAO and its partners have for continuing to keep the JCMT at the cutting edge of sub-millimeter science.

Organizer: Jessica Dempsey

 6:00pm: Welcome and introduction (Paul Ho)

JCMT Legacy Science: New Insights
6:10pm: The Cosmology Legacy Survey (Jim Geach)
6:25pm: Current and future directions in star formation research with the JCMT (Derek Ward-Thompson)
6:40pm: The Nearby Galaxies Survey (Christine Wilson)
6:55pm: The JCMT Legacy Archive (Sarah Graves)

EAO Pilot Science
7:05pm: Highlights from Taiwan (Sheng-Yuan Liu)
7:15pm: Highlights from China (Yu Gao)
7:25pm: Highlights from Korea (Woojin Kwon)

Instrument Directions for JCMT:
7:35pm – 8:00pm: Panel discussion and question and answer session on future instrument upgrades and new instrument concepts.

First Day of Operations

It is with great enthusiasm that the East Asian Observatory (EAO) announces its first day of operations of the James Clerk Maxwell Telescope (JCMT). The JCMT is the largest astronomical telescope in the world designed to operate in the sub-millimetre wavelength region of the spectrum. EAO is now in charge of JCMT operations in partnership with the UK and Canadian research communities.

Paul Ho the Director General of the East Asian Observatory said “It is a great opportunity for the East Asian Observatory to take over the operation of JCMT which is an excellent facility with extremely powerful instrumentation. Many of our astronomers in East Asia have long been involved in pursuing the most important problems in astronomy by utilizing the amazing telescopes on top of Mauna Kea. It is a great privilege for us to be able to work at the best site for ground based astronomy in the Northern Hemisphere. For all of us at the JCMT, we look forward to an exciting future in continuing to deliver frontier science to our communities.”

EAO would like to thank the people of Hawaii for allowing our astronomers to work on top of one of the most beautiful places on earth.


The JCMT handover signing: Back row left to right: Jun Yan, Director, National Astronomical Observatories of China, Dr Guenther Hasinger, Director, Institute for Astronomy, University of Hawaii, Professor Gary Davis, former Director of the Joint Astronomy Centre. Front row left to right: Dr Paul Ho, Director General, East Asian Observatory, Professor Matt Platz , Assistant Chancellor for Academic Affairs, University of Hawaii, Professor John Womersley, Chief Executive STFC. (Credit: Hollyn Johnson/Professor Gary Davis/STFC)

As a memento of this transfer Will Montgomerie, an operator at the JCMT, has released this beautiful night sky time-lapse montage featuring the Telescope:


The Science and Technology Facilities Council of the UK have also issued their own statement about this occasion. The statement can be found here.