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Satellites Taking Pictures of Rockets Carrying More Satellites

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Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#31

Post by kevin_thibedeau »

Iv wrote: post #28
dopeboy wrote: post #15

Kind of offtopic but I figured I'd ask: how close are we to enemy of the state style satellites that can track movement like a overhead CCTV camera?

20 years ago they pretended it was good enough to differentiate between Saddam Hussein and his decoy lookalikes. It is possible however that they made that up to not reveal an internal source of intel. I, for one, think we have been there for a while. The tech is not hard: camera with huuuuge optics will bring you there. The military have secret satellites with undisclosed specs, that's what they have been doing sinc…

The government never made those claims. The media has fanciful ideas of what our imagery capabilities are and it isn't in the government's interest to correct them.

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#33

Post by valuearb »

tenpies wrote: post #25
oelmekki wrote: post #19

Each time I'm sad we're not exploring galaxy star trek style yet and the space conquest made a flop, I remember how many commercial satellites are around here. It really has this regular taste of things you think just died after being hyped (the moon landing) and which you suddenly realize has got slowly, steadily, discretely omnipresent since then without anybody noticing much (granted, satellites are not as cool as…

It has basically fallen into a classic hype cycle - https://en.wikipedia.org/wiki/Hype_cycle This is partly why I'm skeptical of technologies when the media is talking about them. It probably means we're somewhere on the peak of inflated expectations.

The peak of inflated expectations was the Saturn V. Custom built, massive, cost around $10,000/lb in present day dollars to low earth orbit.

The trough of disillusionment was the Shuttle. Much smaller payload capacity, trapped in LEO so it ended manned deep space exploration, and cost around $50,000/lb to LEO.

The Falcon Heavy is the highest capacity launch system since the Saturn V, and will cost $1,000/lb to LEO. I think the plateau of productivity approaches.

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#34

Post by jsmthrowaway »

Iv wrote: post #28
dopeboy wrote: post #15

Kind of offtopic but I figured I'd ask: how close are we to enemy of the state style satellites that can track movement like a overhead CCTV camera?

20 years ago they pretended it was good enough to differentiate between Saddam Hussein and his decoy lookalikes. It is possible however that they made that up to not reveal an internal source of intel. I, for one, think we have been there for a while. The tech is not hard: camera with huuuuge optics will bring you there. The military have secret satellites with undisclosed specs, that's what they have been doing sinc…

The tech might not be hard, but stationkeeping an orbit on top of a target is, unless you have optics that can handle 36,000 kilometers of distance (geosynchronous). All other, lower, orbits involve the satellite hauling ass across the ground, usually at 5+ kilometers per second. The video would be great for about five seconds.

Real spy satellites have time windows and image like hell within the window, then adjust for the next orbit and wait 90 minutes. They’re often in polar orbit, too, because then you get different parts of Earth as it rotates under you. Satellite surveillance is quite tedious, and the enemy knows where and when they are.

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#35

Post by jofer »

nine_k wrote: post #29
jessriedel wrote: post #23

Earlier quoted context omitted.

Any idea why the minimum area requirements exist? It completely kills localized applications like a single farm. It seems like a minimum price, which you could also reach by committing to buy regular photos for a period of time, would be a lot more flexible.

I suspect it's related to the need to possibly re-orient the satellite to have a particular place visible by the camera. It must be relatively slow, and possibly even cost reaction mass, thus the commitment to shoot more of the same area.

Rapideye and SkySat aside, Planet primarily operates a monitoring constellation, rather than a tasking constellation. The doves (satellites used to take this and the satellites being launched) are focused on imaging the land surface of the Earth with an approximately daily cadence. They don't target a particular area, try to reorient, or even have active propulsion (just reaction wheels).

This is an exception -- the satellite was tasked to try to capture this and did reorient itself to do so.

For the most part, though, the doves just point straight down and capture images whenever they're over land and it's not forecast to be completely cloudy. There are over a hundred of them imaging the earth like a line scanner as it rotates beneath their orbit.

The Rapideye satellites operate completely differently, though. They are tasked, and do have to reorient as you mentioned, thus the minimum area requirement for acquisition of Rapideye imagery.

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#36

Post by jessriedel »

nine_k wrote: post #29
jessriedel wrote: post #23

Earlier quoted context omitted.

Any idea why the minimum area requirements exist? It completely kills localized applications like a single farm. It seems like a minimum price, which you could also reach by committing to buy regular photos for a period of time, would be a lot more flexible.

I suspect it's related to the need to possibly re-orient the satellite to have a particular place visible by the camera. It must be relatively slow, and possibly even cost reaction mass, thus the commitment to shoot more of the same area.

Oh jeez, I didn't even consider that they'd actually be orienting satellites in response to orders. (Although, does that make sense for "archival imagery"?)

I guess maybe this restriction might be lifted when Planet deploys enough coverage to be imaging the entire Earth daily?

https://www.planet.com/pulse/planet-launches-satellite-const...

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#37

Post by anon5289602 »

Iv wrote: post #28
dopeboy wrote: post #15

Kind of offtopic but I figured I'd ask: how close are we to enemy of the state style satellites that can track movement like a overhead CCTV camera?

20 years ago they pretended it was good enough to differentiate between Saddam Hussein and his decoy lookalikes. It is possible however that they made that up to not reveal an internal source of intel. I, for one, think we have been there for a while. The tech is not hard: camera with huuuuge optics will bring you there. The military have secret satellites with undisclosed specs, that's what they have been doing sinc…

Huge optics is one option

https://en.m.wikipedia.org/wiki/Synthetic-aperture_radar

https://en.m.wikipedia.org/wiki/USA-215

Things in space can often be seen with a good from the ground.

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#38

Post by [deleted] »

Iv wrote: post #28
dopeboy wrote: post #15

Kind of offtopic but I figured I'd ask: how close are we to enemy of the state style satellites that can track movement like a overhead CCTV camera?

20 years ago they pretended it was good enough to differentiate between Saddam Hussein and his decoy lookalikes. It is possible however that they made that up to not reveal an internal source of intel. I, for one, think we have been there for a while. The tech is not hard: camera with huuuuge optics will bring you there. The military have secret satellites with undisclosed specs, that's what they have been doing sinc…

[deleted]

Re: Satellites Taking Pictures of Rockets Carrying More Satellites

#39

Post by jessriedel »

jofer wrote: post #35
nine_k wrote: post #29

Earlier quoted context omitted.

I suspect it's related to the need to possibly re-orient the satellite to have a particular place visible by the camera. It must be relatively slow, and possibly even cost reaction mass, thus the commitment to shoot more of the same area.

Rapideye and SkySat aside, Planet primarily operates a monitoring constellation, rather than a tasking constellation. The doves (satellites used to take this and the satellites being launched) are focused on imaging the land surface of the Earth with an approximately daily cadence. They don't target a particular area, try to reorient, or even have active propulsion (just reaction wheels). This is an exception -- the…

Thanks very much for this excellent comment.
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