On Monday MBO was invited to bring our Murchison Widefield Array (MWA) radio telescope tile to Scienceworks as part of the invitation only premiere of "Capturing the Cosmos", the new planetarium show that the Melbourne Planetarium and CAASTRO have been working on for the last 2 years. We linked up with the Telescopes in Schools project as well as Ben Mckinley and Jack Line from the University of Melbourne (two radio astronomers who use MWA) plus, of course, CAASTRO and Scienceworks to make this happen.
The Sunday before was our March working bee at MBO and myself, Lindsay (who leads the MBO radio astronomy group) and Anthony (our secretary) met up to load up the MWA tile and the newly acquired wire mesh (thanks to Wiebke Ebeling from CAASTRO!) for it to sit on and shipped it all across Melbourne to Scienceworks to be stored until Monday morning.
On Monday I met up with Peter from MBO in the city and to travel to Scienceworks. Arriving at 9:30am we met up with Kylie from CAASTRO and Jack from the University of Melbourne and proceeded to unbox and construct the telescope, joined shortly after by Jacinta from Telescopes in Schools and Ben Mckinley from UoM.
This was the first time we were able to have a Low Noise Amplifier (LNA) in each of the 16 antennas that make up the tile (huge thanks to David Emrich from Curtin University for that) and so we were able to demonstrate the tile with the all inputs of one polarisation connected - in this case the X polarisation. We fed the X polarisation output from the beamformer into a R820T2 Software Defined Radio (SDR) received plugged into a Linux laptop running the open source gqrx software and then proceeded to show that there are very good reasons why MWA is out in the middle of the desert in Murchison Shire in Western Australia (population ~120, population density 0.002303/km2).
Currently we cannot control the delays on the beamformer inputs so we demonstrated it in its default state of looking straight up. Despite that we had a really good reception of ABC Classic FM (and other radio stations) which would have been coming in from a transmitter effectively on the horizon. You will notice that the software is tuned at 105.9 MHz, which is right in the band that MWA is interested in (80 MHz through to 300 MHz) and a very good signal despite the tile having a beam looking at 90° to the source.
That evening we were joined by the MBO outreach team in the form of Heike, Sue and Lachlan to provide extra support for the launch guests. The official launch event itself was well done with Dr Nurin Veis (manager of Scienceworks), Dr J. Patrick Greene (CEO Museum Victoria), Professor Elaine Sadler (director of CAASTRO) and the unmistakeable Professor Brian Schmidt (Nobel laureate, CAASTRO member and VC of ANU) all speaking in between the two invitation showings of the planetarium show (to which we we were able to go to the second).
The show? It was my first time to the Melbourne Planetarium and I can say I was impressed - whilst I was familiar with a lot of the content it was very well presented and very accessible and the choice of Geoffrey Rush as narrator was spot on. Go see it - it's now open around Australia!
- Chris Samuel