A small but powerful array. The MWA antenna has sixteen croos dipoles. It is powered by a 35kVA trailer-mounted single phase diesel generator. I'm sure in the expanded form they will have grid connectivity. (via MWA)
After five long years of development and construction the Murchison Widefield Array (MWA) Observatory, located in Western Australia, is finally completed and currently undergoing preliminary testing. The array is a joint effort between institutions from the US, India, New Zealand and Australia with a main mission to study the sun, its heliosphere, the Earth’s ionosphere, radio transient phenomena (extremely distant galaxies) and to detect neutral atomic Hydrogen emission from the cosmological ‘Epoch of Reionization’ (AKA: studying the phase-change of hydrogen approx. 400,000 years after the Big Bang). Considered one of the largest radio observatories on the planet, the MWA consists of (currently) 128 (4m X 4m) ‘tiles’ with dual-polarization dipoles that have a frequency spectrum of 80-300MHz which are spread out over an area of almost 2 miles in diameter. Initial testing showed that the observatory could not only observe distant celestial bodies but also those found closer to home. In particular, space junk orbiting in low-earth orbit. Everybody knows that space junk creates an inordinate amount of problems for both astronauts as well as equipment that is deployed in space. Current estimates put the orbiting junk pile at about 21,000 pieces that are 10cm or bigger in size. According to MWA director Steven Tingay, the observatory is capable of continuous tracking of those objects rather than calculating trajectories taken from snapshots. Current tracking methods involve ground-based radar that is capable of following 200 pieces of debris a day while the MWA is theoretically capable of tracking thousands simultaneously, which equates to almost the whole debris field tracked over one night. To test their theory of tracking junk the research team used the MWA to receive FM radio signals bounced off of the ISS, which is over 100m wide, and successfully tracked over a distance of almost 8 miles. While that may not sound so fantastic, the data will be used to refine the radio technique to scale it down to tracking material at 10cm in size. Eventually the Observatory will gain a build-up of 256 tiles in order to gain increased sensitivity and resolution which will make the process that much easier.
See more space debris cleaning options: