I'm not sure what excites me more about the potential of Planetary Resources:Having a catalogue of potentially civilization saving information (orbits of NEO's)Discovering zillions of exoplanets through optical interferometryThe new data we can collect about our solar system, including through visual observations.A map of noteable Kuiper and Oort objects along with high-res photos of many of them.The improved resolution of various interstellar phenomenonHaving very regular high-res updates (and historical database) to google earth (or perhaps it will be called PR-Earth)The potential for abundant volatiles and metals that could be processed in space and used for in-space habitation and transportation by all comersThe impact it will have on STEM outreach
Their telescopes are just a cheap platform to do astronomy and Earth observation. Optical interferometry is hard, though, and I think it'd be wise not to jump to conclusions about their ability to do that.
I agree, it is premature to jump to conclusions about their ability to do optical interferometry, however I think there are a lot of small scattered indications that support the conclusion that they intend to try. Given that this is relatively low cost hardware that can be test flown as design iterations very frequently if they choose, I don't see any reason except their own motivation to not keep iterating until they work the kinks out of how to make it work.I'd be dubious if the hardware were much more expensive, or if they didn't have such deep pockets backing them, but they are talking about something that should be pretty amenable to testing and tweaking and seem to have the financial wherewithal to do so.
That was partially my point: that if they wish to do interferometry the hardware will be much more expensive. However, as you say, they have considerable financial wherewithal.
Quote from: douglas100 on 05/05/2012 08:43 pmThat was partially my point: that if they wish to do interferometry the hardware will be much more expensive. However, as you say, they have considerable financial wherewithal. What makes you so confident that there is no (relatively) low cost way they might come up with to solve this problem?(please take this as a genuine question, and not disagreement disguised as a question, I know absolutely nothing about the technical challenges involved and I am curious)
So what do they need interferometry for?
How is interferometry going to make them a lot of money?
The number one issue for an imaging interferometer is the time of acquisition, all the imagers must have good synchronized clocks - at least at nanosecond time scales, these exist and are not terribly hard to operate in space (invar mounts, rad hardened, insulated, thermal stabilized), but without this minimum capability all else is moot.
Quote from: BrightLight on 05/06/2012 05:51 pmThe number one issue for an imaging interferometer is the time of acquisition, all the imagers must have good synchronized clocks - at least at nanosecond time scales, these exist and are not terribly hard to operate in space (invar mounts, rad hardened, insulated, thermal stabilized), but without this minimum capability all else is moot.GPS can be used to assist time synchronization. Though obviously that's a little more tricky in orbit.
Quote from: Robotbeat on 05/06/2012 06:17 pmQuote from: BrightLight on 05/06/2012 05:51 pmThe number one issue for an imaging interferometer is the time of acquisition, all the imagers must have good synchronized clocks - at least at nanosecond time scales, these exist and are not terribly hard to operate in space (invar mounts, rad hardened, insulated, thermal stabilized), but without this minimum capability all else is moot.GPS can be used to assist time synchronization. Though obviously that's a little more tricky in orbit.Absolutely, but GPS NEMA strings are around 2 Hz, and even with WAAS, you have millisecond timing, one needs atomic clock scale timing on each platform.
Quote from: BrightLight on 05/06/2012 06:23 pmQuote from: Robotbeat on 05/06/2012 06:17 pmQuote from: BrightLight on 05/06/2012 05:51 pmThe number one issue for an imaging interferometer is the time of acquisition, all the imagers must have good synchronized clocks - at least at nanosecond time scales, these exist and are not terribly hard to operate in space (invar mounts, rad hardened, insulated, thermal stabilized), but without this minimum capability all else is moot.GPS can be used to assist time synchronization. Though obviously that's a little more tricky in orbit.Absolutely, but GPS NEMA strings are around 2 Hz, and even with WAAS, you have millisecond timing, one needs atomic clock scale timing on each platform.Can you have the master clock on one satellite and derive the time from a control signal at the other satellites?If you bounce the control signal back distance and time delay can be measured.
Would interferometry work for getting higher resolution of Earth from orbit?