Discussion of Future Space Telescopes

[JB47394]

Indeed

I'm not completely handwaving this. Imagine if there was a control signal being fed into the satellites, like a laser guide star to eliminate atmospheric turbulence in current telescopes. That sort of thing is used elsewhere for obscure stuff like resolving bounced light off diffuse surfaces. Such a control would be used for signal alignment purposes. There are a lot of clever people out there and I'm confident that this nut could be cracked.

 

[mongo]

I'm not completely handwaving this. Imagine if there was a control signal being fed into the satellites, like a laser guide star to eliminate atmospheric turbulence in current telescopes. That sort of thing is used elsewhere for obscure stuff like resolving bounced light off diffuse surfaces. Such a control would be used for signal alignment purposes. There are a lot of clever people out there and I'm confident that this nut could be cracked.

I was referring to digitizing light as needing higher levels of engineering than we have now.

Theoretically a group of sats could bounce the image to a collection/ processing sat (or ground in a vacuum) if there was a fast enough actuation system with enough dynamic range to path match a further delayed version of the image. A multibounce assembly trades precision for range and a smaller setup could do fine tuning.

 

[JB47394]

I was referring to digitizing light as needing higher levels of engineering than we have now.

Gotcha. I don't know what the state of the art is in this field. I've talked to my chatbot about it, and it assures me that there are digital interferometers, but I'm not smart enough to understand the implications. Digital holography was also mentioned, but that seems to be the reverse of interferometry.

 

[bxr140]

And I'd guess there is a market for "connect to our telescope constellation--point the telescope where you want (with certain restrictions)".

Unfortunately even the market of earth facing instruments is tough--there's basically no market for things that point away from earth that's not pure science*** All the money there pretty much comes from a combination of national pride and sciencey-type grants. (***There's defense stuff that points from ~LEO out to GEO, but that's a whole different subject...) There's been a gazillion attempts at commercializing earth facing imaging over the past 10-15 years or so, but very few folks have actually been successful...major exceptions (Maxar/Digital Globe, for example) are significantly anchored by defense.

FWIW, similar to what I think you intended in the quote above, one of the early business pillars of Skybox was enabling users to directly task and receive imaging data, to the point of users being able to host 'light' versions of a ground station on site for literal direct tasking and data downlink. Skybox dropped the idea because there was so little interest--time has shown that most customers interested in 'information from space instruments' (visible light imaging and beyond) are actually much more interested in paying for processed outputs rather than raw data.

All of that gets infinitely worse when the apertures are pointed away from earth, because the things that get put in space for those applications need to be so exquisite that they end up being massively expensive and, again, there's really no commercialized money on the demand side. Slapping some low cost instruments on a bunch of starlink sats, for instance, isn't a practical solution. (It's the equivalent of Planet's ~3-5m resolution cubesat constellation vs a sub-meter provider). Making a dedicated SX-based constellation that would actually return better-than-existing science would require modification of existing satellite concepts to higher precision and reliability (= $$$), and again, there's no money there.


Not actually related, and mostly self deprecating SPAM, a number of years ago a partner and I tried to startup an aggregation service that would basically abstract/broker a customer image request from a satellite imaging company. The thesis was that 1) a customer doesn't really care where an image actually comes from, and 2) the product coming out of any one entity in the fledgling low-cost imaging space wasn't really enough to sustain exclusive customer-supplier relationships. So...our model was basically to provide a aggregated 'menu' (of sorts) from the dozens of image providers based on things like resolution, timeliness, image geometry, etc, then we also had aspiration to open up access to consumer level customers. TLDR: It failed miserably, partly because we were shitty business people, but mostly because (as noted above) most reliable customers actually don't care about the actual "picture".

 

[ecarfan]

A LISA-like instrument should be able to measure relative displacements with a resolution of 20 picometres—less than the diameter of a helium atom—over a distance of a million kilometres

My mind is having a great deal of difficulty comprehending that sentence.

 

[nativewolf]

It has more snow, lower elevation that current mountain sites, and is sunlit a lot (only 3 months without twilight) without the benefit of vacuum.

Damn Ozone treaties, thought I had that problem about licked but no.....

 

[scaesare]

It has more snow, lower elevation that current mountain sites, and is sunlit a lot (only 3 months without twilight) without the benefit of vacuum.

Not to mention the Abominable Snowman danger...