[mturmon]

The use of a relay is something less than "stunning" and "brilliant". The use of relay satellites when ground stations do not have line-of-sight to the primary spacecraft (or, when you have reduced bandwidth or other restrictive conditions) is standard practice. This concept is used to relay telemetry from Mars landers, for instance.

[jackconnor]

You realize the words "stunning" and "brilliant" are subjective, right? Your "standard practice" here is both incredible AND the first time ever done in this scenario to achieve something brand new in space travel. Not sure why you need to tell people not to like things, but it's a really bad habit you should break.

[mturmon]

I do like the notion of using a relay.

In 1999, JPL lost Mars Polar Lander, and didn't have telemetry to know why. One of the major lessons learned from this loss was to always have telemetry of Entry, Descent, and Landing (EDL). This telemetry is usually provided by a relay. So despite the fact that we both like it, using relays is not new.

(See sec. 5.1 of [1]: "The omission of EDL telemetry was justifiable from a project perspective. However, the loss of MPL without yielding any clues as to the cause of the loss jeopardized the potential for success of future Mars landers. Therefore, the decision was not justifiable in the context of MPL as one element of the ongoing Mars exploration program.")

I like that they put it in an orbit about the Earth-Moon L2 point. I think it's the first such satellite there.

[1] https://spaceflight.nasa.gov/spacenews/releases/2000/mpl/mpl...