We Really Need a Far-Infrared Space Interferometer. Here's Why

Fraser, if Planet 9 is 500AU out (semi axis major) then it likely has a surface temperature of about 20 kelvin, using Wien's law we get 2898/20 = ~144.9 micometers. This falls well within the far infrared end of the spectrum. I would argue that w dedicated outer solar system explorer that utilised the far Infra Red, from around 80 microns to say 500 microns would be epic for finding out what bodies exist in the outer solar system, if we can create a better catalogue of TNOs, scattered disk and kuiper belt objects, we may get closer to either proving or disproving Planet 9 as well as building a better picture of those dim, dark depths of the solar system.

More wavelengths to see with are always good. Looking forward to watching this one! I hope to live long enough to see a far side of the Moon HF/LF/VLF/ULF receiver array whether in orbit or on the moon, along with a compact among all lunar-bound nations to declare the moon a radio quiet zone. I am given to understand that Hot Jupiters can be detected via their HF emissions, as could brown dwarfs. It might even be possible to detect Jupiter type gas giants if they have a large magnetic field and storms. This would give us another set of tools to find planets with longer orbital periods. Laser communication arrays, strong shielding and good design can eliminate spurious signals-which digital communications in the RF bands are notorious for emitting. If you like some Starlink satellites in your night time viewing star party, you would love what a bunch of cell phones, a router or an Ethernet cable do for radio reception.