Why do we use radio to observe the universe?
There’s particular science that can only be done in radio wavelengths. You just need to look back at the last 30 or 40 years or so of astronomy – a lot of the big discoveries have been made at radio wavelengths. Particularly the pulsars, which were discovered in the UK, could not have been done in any other wavebands. I’d say that this is a very big example of needing to study the universe in radio wavebands.
Things like looking at complex molecules – which are very interesting for people looking for life in the universe
– is another example and one which is going very well in radio wavelengths. And looking back in time is also very good in long radio wavelengths, since they can see through all of the obscuring matter in space in order to go way back to the beginning of the universe, which can be very hard to do at optical and other wavelengths. It’s the way that a lot of astronomy has been done.