semaphoreP

قبل 4 سنواتdiscuss

Probably pretty difficult to find too many compelling cases. The bands starlink transmits in are designated communication bands, so interference from other satellites is going to be so high that it will drown out any signals. There are astronomers working on removing this foreground, but it's really difficult! It's actually becoming quite a problem in radio astronomy with the amount of the electromagnetic spectrum that is quiet enough for science.

semaphoreP

قبل 4 سنواتdiscuss

Astronomer here, we are thinking about doing interferometers in space[1,2], but it won't be a catch-all for everything. One reason is that the instrumentation is equally as important as the telescope optics itself, and it's non-trivial to have your swarm of satellites both collect light, but also do science experiments with the light. One thing we are thinking of is to fly more proto-typing missions to get the technology readiness of various components to mature stages before assembling it all together for the real thing (I would say we did not do this as well for JWST).

[1]: https://www.life-space-mission.com/ [2]: https://lisa.nasa.gov/

semaphoreP

قبل 5 سنواتdiscuss

Note that in these images, the planets are unresolved. They are point sources. Point sources span multiple pixels due to the sampling theorem.

semaphoreP

قبل 5 سنواتdiscuss

And this is the program that will study this system: https://www.stsci.edu/jwst/science-execution/program-informa...

semaphoreP

قبل 8 سنواتdiscuss

Ah my bad, I mean that in the visible, you can't reach the diffraction limit with AO like you can in the near infrared. Certainly impressive matching HST from the ground.

I don't think past 5 microns there's been a lot of science done from the ground (not counting SOFIA). Practically, I think everyone is waiting for JWST. A lot of the interesting molecular lines also get absorbed by the Earth's atmosphere.

semaphoreP

قبل 8 سنواتdiscuss

Adaptive optics is really only effective in the infrared. And really only in the near-infrared, as past 5 microns, we can't really see through the atmosphere. In the visible, ground-based can't match space observatories (in the visible, the atmospheric turbulence is way harder to correct for).

semaphoreP

قبل 8 سنواتdiscuss

It's not the absolute value of the signal. What they're measuring the amount of water compared to hydrogen.

semaphoreP

قبل 8 سنواتdiscuss

It's hard to measure absolute water abundances (it requires a lot of assumptions and extrapolating). This is a relative comparison of atmospheric water. We don't have relative water abundances for a lot of planets, so it's on the higher end, but we don't really know (maybe some other planets' water are hidden behind clouds).

semaphoreP

قبل 8 سنواتdiscuss

It will be very tough with JWST. Many of the biosignatures are small features, and not so easily detected. There's only a handful of planets for which this might be close to possible.

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