Slashdot Mirror

These are cube sats, so they only produce images with a resolution of about 3-5 meters. Not really enough to make out cars on roads. The smallest recognizable object is about house-sized. Their imagery is of more interest to earth and atmospheric scientists.

Resolution of a telescope is inversely proportional to the diameter of its optics. Spy satellite resolution is about 13 cm, or 5 inches - an ex-NRO official is on record stating that they could see how many plates you set out on a picnic table. To get that resolution, the primary optic needs to be about 2.4 meters in diameter.* Which not-so-coincidentally is the diameter of Hubble's primary mirror. Hubble's size was dictated by the Space Shuttle's cargo bay, and the cargo bay was designed to hold (among other things) a Keyhole spy satellite for launch, maintenance, and refueling. Hubble is basically a spy satellite pointed up instead of down.

* Your primary optic doesn't have to be round. It's possible to create a larger synthetic aperture via an interferometer - two (or more) small mirrors separated by a large distance. You lose signal to noise ratio (which shouldn't be a problem for something brightly lit by sunlight), but gain resolution as if your optics were a mirror with the diameter of the separation between your small mirrors. I suspect newer spy satellites are of this design, giving them much higher resolution (the primary constraint would then be atmospheric turbulence). The unfurling mirror design of the James Webb Space Telescope relies on the same mechanics as would be needed for an interferometer spy satellite. This isn't really viable with cube satellites - the mirrors have to be aligned to within a fraction of a wavelength of light to create an interferometer, so a large rigid structure is crucial.

Among the foreign satellites, 88 cube satellites belonged to San Francisco-based earth imaging startup Planet. With the launch, the company has increased its fleet to 143 satellites which will soon begin capturing images of the earth's entire landmass, including India, every day.

so, just another 88 spy satellites?

yup.

https://www.planet.com/markets...

Planet Labs' approach to orbital debris mitigation is discussed here: https://www.planet.com/pulse/k... tl;dr the satellites re-enter and burn up very quickly, most within a year or so.

Yes, and >100 NON hardened satellites in orbit today work only thanks to magic, right?

https://www.planet.com/

NASA is terrible. They take too long to do anything, and are stuck in the mindset that everything needs to be rad-hardened and this and that. Fact is, these guys are eating their lunch for developing interesting stuff in space.

NASA sucks at this. They move too slowly. You need a company who develops and turns around stuff in three weeks, like these guys. Incidentally, they operate the largest constellation of anyone--and don't use rad hard parts or all this other stuff. They do on a shoestring in a month what NASA does for billions in 20 years.

Let's not go there... In X+1 years when GoldenPalaceCasino.com goes out of business ,Verisign will take the rights to the domain AND the planet!

Yay! Planet Squatting!