Does the design only capture ripples travelling in the ecliptic?
Here's a pretty great infographic on how they plan to collaborate with the Athena x-ray observatory to detect black hole mergers ahead of time - https://www.esa.int/ESA_Multimedia/Images/2019/05/How_can_LI...
It ends up being about 0.4 square degrees in the sky that they're able to narrow in on before the event. That narrowing takes roughly a month.
(In fact, it has to: in order to keep each leg the same length, each spacecraft must be the same distance from the Sun. There's no way to do that in a free falling orbit and have the formation flat to the ecliptic-- the craft closer to the Sun would orbit faster and drift away from its brothers.)
They're already planning for something like that!
Less flippantly, is LISA funded?
Formally ESA has moved the LISA project into a "implementation phase", meaning they intend to build it, but no money has been "pledged" as far as I know. However, LISA is a flagship Space Science programme, and the SSPs are part of the ESA budget all member states must contribute to.
Basically there's a fixed, overall budget that is then split for each project adopted. So there is definitely money but I'm not sure there is a public statement that "this particular pile of money belongs to LISA"
Also, how can the test masses remain in free fall, while each satellite is undergoing course corrections? Or are corrections infrequent enough for satellites in this earth-following orbit that it wouldn't cause any real amount of downtime? Of course Earth is free-falling.
Yes, solar. Laser power is only 5 watts. Total spacecraft power is 760 watts. They're downlinking a mere 334 megabytes a day, sampling at 3.3Hz.
>how can the test masses remain in free fall, while each satellite is undergoing course corrections?
That's the hard part. The test mass floats in the middle of the spacecraft, which maneuvers around it, occasionally firing ultra low-impulse cold gas thrusters to counteract drag. They put up a spacecraft back in 2015 to test that concept: https://en.wikipedia.org/wiki/LISA_Pathfinder
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