Observing Tool (Software Installation)

Observing Tool

The Observing Tool is a Java based application for creating Science Programs. This is the software used to create and upload the details (position, time, offsets etc.) of a science observation to our system.


While Linux based operating systems are our lead platform, testing has been performed to varying degrees on Solaris, Windows and Mac OS X.

To acquire and run the Observing Tool requires having a version of the Java Runtime Environment greater or equal to 1.6. If you are unsure whether or not you have Java installed and in your path, or which version of Java you have, open a console and type the following:

$ java -version

Responses such as "command not found" indicate that either Java has not been installed or is not in your path.

It is recommended that you obtain the latest Java Runtime Environment from Oracle.

OpenJDK (including NetX and IcedTea) is known not to work. If “java -version” displays information including the name “OpenJDK”, please use Oracle’s version of Java instead. This gives output mentioning “HotSpot”, for example:

java version "1.6.0_15"
Java(TM) SE Runtime Environment (build 1.6.0_15-b03)
Java HotSpot(TM) 64-Bit Server VM (build 14.1-b02, mixed mode)

Note: we have encountered a problem (this bug) with Java 1.8.0_91 and 1.8.0_92 where the OT can run extremely slowly. The problem appears to have been fixed in Java 1.8.0_101.


Security Settings

Depending on your Java security settings, you may need to add our site to a list of exceptions before you can run this software. To do this, open the Java Control Panel, select the Security tab, and add http://ftp.eao.hawaii.edu/ to the “Exception Site List”. As of version 9 of the JDK, the “Exception Site List” can be found in the “Web Settings” tab rather than the “Security” tab.

To open the Java Control Panel:

  • On Linux, you may have a command “jcontrol” to open it directly. Otherwise try “javaws -viewer” (which opens the control panel and web start viewer) and dismiss the web start viewer.
  • On Windows prior to windows 8, open the Control Panel and select Java; on windows 8 search for ‘Java Control Panel’ and open that.
  • Mac OS X, go to Systems Preferences -> Java.

Again, depending on your security settings and whether you have run the software before, you may have to manually accept several warnings about “self signed certificates” before the OT will start.

Installation and First Run

The Observing Tool for both telescopes is distributed via Java Web Start.
You can install and run the Observing Tool from the console by typing:

javaws http://ftp.eao.hawaii.edu/ot/jac-ot.jnlp

Alternatively, depending on your browser and Java configuration, you may be able to click on the following link:

JCMT-UKIRT Observing Tool

On Mac OS X, to use this link, you may need to go to System Preferences -> Security & Privacy and allow software from unidentified developers, however this will lower the security of your computer.

Re-running and Updates

Installation may create a shortcut icon on your desktop, or an entry in your start menu, so that the Observing Tool can be run again in the future. While an active internet connection is required for initial installation, it is not required for running the Observing Tool on a day-to-day basis, and thus can be used in the absense of an internet connection. If a desktop icon is not created, you can check the status of, and run the Observing Tool, from Java Web Start by opening a console and typing:

$ javaws -viewer

Due to the nature of Java Web Start, upgrades of the Observing Tool happen automatically whenever the code is updated providing you have an active internet connection, so there is no worry about running the correct version.

Note: when certain package information is updated, the Java Web Start system may replace the OT icon on your desktop with a new launcher. Please be aware that this can cause any personal links which you made to the original launcher to no longer work. If this happens, you should be able to create new links based on the updated desktop icon.


Should for any reason an upgrade fails due to a cached item, or if you wish to remove the Observing Tool, it can be uninstalled by opening a console and typing the following:

$ javaws -uninstall

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