/sci/ - Science & Math

>>12317960
>Station keeping is costly.
So is landing on the Moon, but not all orbits require significant station keeping.
>Also with the lunar base we are practically promised since
Any decade now. The astrophysics division are unlikely to commit to any mission if it depends heavily on human space flight, which is very politically unstable.
>You can still cover a lot of interesting areas.
Some, and it's bad for interferometry.
>What other ways to achieve >400,000 km baselines do you propose?
Can be done in Earth or solar orbit. But in any case the requirements are driven by the science, not the other way round. Extremely long baselines face the problem of resolving out flux. You can't just make an enormous interferometer without a science case because it won't be sensitive to objects which are much bigger than the resolution (most of them).
>We are talking about radio astronomy, how does UV come into radio astronomical baselines?
UV does not mean ultraviolet in this context. U and V are the names given to the directions in Fourier space. To get good interferometry you need a range of baselines and angles, this is called filling the UV plane. Each pair of baselines at a single moment only measures one spatial frequency in one direction. A pair of baselines measures a point in the UV plane.
>What wavelengths? The antenna scales with wavelength so multi km wavelengths require a pretty large satellite if you want to keep it in space.
>What wavelengths?
20-140 MHz usually, it's where the strongest science case is.