20 May 2015
In with the new: Astronomers can now drive research telescopes using their smartphone!
The South African Astronomical Observatory (SAAO) has been a hive of activity lately with astronomers and engineers busily upgrading and improving the observatory’s smaller telescopes. To keep these telescopes internationally competitive the SAAO has installed a new improved detector called the “Sutherland high-speed optical camera” (SHOC) used on its existing 1.9 m and 1 m telescopes and is installing two new telescopes to replace those which were donated to the University of KwaZulu-Natal and the University of the Free State in early 2015. Along with the new telescopes and instruments, brand new software has been developed in house to support astronomers using the new facilities. The new software to drive the SHOC instrument has been designed to be used within a web-browser so that astronomers can control the camera from a remote computer, laptop, tablet or even their smartphone! In the coming months, the SAAO hopes to release the software into the Open Source community, thereby aiding other observatories around the world as well as amateur astronomers. It looks like the days, or rather nights, of astronomers freezing while observing up the mountain in Sutherland could soon be numbered!
An in-house SAAO team have recently released new software to drive the new SHOC instrument which is used on the SAAO’s 1.9 m and 1 m telescopes. Originally, SHOC was controlled using software supplied by the camera manufacturer Andor. However, in order to fully customize the software and to allow for future extensions, the SAAO team collaborated to produce new Open Source software to drive SHOC via a web-based user interface. This new software also has the advantage of allowing users to control the SHOC instrument from any location, ushering in a new era of remote observing at the SAAO.
Software engineers Dr Carel van Gend and Briehan Lombaard have developed a simple web-based user interface which astronomers use to control all aspects of data acquisition using SHOC. Astronomers can use the interface to select the camera exposure time they require and the colour filter they wish to use, along with any other requirements for their observations. Once an astronomer has selected the appropriate configuration for their observation, all they have to do is hit the “start” button. The software then “drives” the instrument which automatically configures itself, takes the required picture and saves the data in a computer file for the astronomer to analyze later on.
Dr Carel van Gend, a principal software engineer on the project says:
“We wanted to improve the functionality of the previous software, make it more convenient and intuitive for astronomers to use, and to move towards the long-term goal of making the instruments and telescopes be remotely operable. We’ve done this, and along the way we’ve made the software more robust and easier to maintain and extend.”
In addition to controlling the camera and instrument, astronomers also required a mechanism to view and analyze their data on the fly. Software engineer Briehan Lombaard was responsible for developing the user interface for viewing and analyzing the data in real-time which is incorporated into the web-browser along with the instrument controls. Images output from the camera are automatically displayed in the web-browser and are updated every second.
The SHOC instrument is designed to take extremely short exposures in quick succession in order to look for rapid changes in the target object. The camera can take up to 100 frames a second, which is four times faster than a normal motion picture! It is therefore crucial that the exact timing of the exposures is known to great accuracy. This is achieved using a GPS (Global Positioning System) receiver in the instrument. A familiar example of the use of GPS receivers is in car navigational aids, however, the space-based satellite navigation system also provides accurate time information for any position on Earth.
Dr Amanda Gulbis, Head of Instrumentation at the SAAO and SHOC designer says:
“The GPS settings can be controlled such that every image frame is triggered to better than micro-second accuracy.”
“While the camera can take data up to hundreds of frames per second, the display only updates every one second or better, depending on the computer network connection.”
One of the first astronomers to use the software, Dr Matt Burleigh of the University of Leicester, UK commented:
“A quick message to say how impressed I was with the performance of SHOC….the new operating software is also very easy to use.”
As SHOC can now be driven from most modern web-browsers, including those on laptops, tablets and even smartphones astronomers are no longer tied to the telescope dome in order to make their observations. To take data, the astronomer can be located in the telescope dome, or remotely from around the world. Van Gend and Lombaard are currently working on an extension to the software which will enable astronomers to pre-configure their observations in advance of a night’s observing.
Van Gend says:
“Eventually we intend that astronomers will be able to configure their observations using only a web-browser, set them running, and download the data when it’s ready without needing to travel to Sutherland, and to stay up all through the freezing night!”
Dr Nicola Loaring, SAAO Outreach astronomer says:
“These new software developments have important implications, not only in terms of efficiency and convenience, but also in terms of cost. The SAAO can expect significant savings in its operations budget by switching from traditional dome based observing to remote observing.”
In the coming months, the SAAO hopes to release the software into the Open Source community, thereby aiding other observatories and amateurs in their endeavors when it comes to instrument building.
Hamish Whittal, SAAO’s IT division manager and member of the project team says:
“We’ve benefited from using open source at the SAAO, and we’re excited to be giving something back.”
Dr Nicola Loaring.