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Comment by jessriedel | Hacker News Reader

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.

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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.

Thanks very much for this excellent comment.

Their strategy is particularly awesome: a hundred of small short-lived satellites (really small, they're 3-unit cubesats, 30x10x10 cm) operating in a swarm. No big deal if a single one is lost: operation can continue with other ones once they are in position. Also, costs are spread due the possibility of servicing several customers simultaneously in separate locations around the globe.

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...

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