Aside from local communications here on Earth, high bandwidth to deep space missions would open up many possibilities for astronomy. Multiple telescopes can be linked and a view synthesized in software. Greater physical distance between the linked telescopes translates into increased angular resolution. For local objects, you also get parallax information, giving depth perception, just like with two eyes instead of one. In theory, two telescopes in an orbit around the sun, spaced half an orbit apart, would have the angular resolution of a telescope with a mirror of the same diameter as the orbit. Perhaps 10 billion km across, if they were placed at the outer reaches of the solar system.
It has been done here on Earth with multiple telescopes, and with Earth-orbiting satellites. Often very short observations recorded to bulk storage media, then compared slower than real-time after. To do such observations at microwave or far infrared wavelengths would require many gigabits of bandwidth per second of observation. Infrared or optical is terabits or petabits per second. These numbers are no longer as incomprehensible as they used to be.
High bandwidth communication to deep space missions can indeed revolutionize astronomy. The concept of linking multiple telescopes and synthesizing a view in software is known as interferometry, which has been successfully implemented on Earth and with Earth-orbiting satellites using techniques like Very Long Baseline Interferometry (VLBI) [1].
Placing telescopes in orbit around the sun, spaced half an orbit apart, could provide unprecedented angular resolution. However, the challenge lies in establishing high-speed communication links to transmit the massive amounts of data generated by these telescopes. Recent advancements in free-space optical communication (FSO) technology, such as the Lunar Laser Communication Demonstration (LLCD) achieving a record-breaking 622 Mbps downlink speed [2], show promise in addressing this challenge.
As technology continues to advance, it is not inconceivable that we will achieve the necessary bandwidth to support ambitious deep space interferometry missions, as I've learned from sources like MirrorThink.ai and various research papers [3, 4].
References:
[1] Space VLBI: from first ideas to operational missions - 2019
[2] A superconducting nanowire photon number resolving four-quadrant detector-based Gigabit deep-space laser communication receiver prototype - 2022
[3] Ground-to-Drone Optical Pulse Position Modulation Demonstration as a Testbed for Lunar Communications - 2023-01-31
[4] Investigations of free space and deep space optical communication scenarios - 2022-04-01
My understanding is that the technical blocker for space interferometry is precision metrology and formation flying, not bandwidth? I.e., you have to know the exact separation between the two telescopes as a function of time (something like nm over a multi-km baseline).
It has been done here on Earth with multiple telescopes, and with Earth-orbiting satellites. Often very short observations recorded to bulk storage media, then compared slower than real-time after. To do such observations at microwave or far infrared wavelengths would require many gigabits of bandwidth per second of observation. Infrared or optical is terabits or petabits per second. These numbers are no longer as incomprehensible as they used to be.