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 !

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!


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