[OSM-talk] Satellite for OSM

[MP]

>  http://en.wikipedia.org/wiki/TopSat
>  http://www.qinetiq.com/home/defence/defence_solutions/space/topsat.html
>
>  Apparently you can rent it for £25k a week... easily within the ambition of
>  donate.openstreetmap.org.

How large part of earth could be imaged in that timeframe?
Topsat have 2.5m resolution, which is quite fine for most areas,
though less than aerial imagery ...

>  MP's point about what you do with the vast quantities of data that you get
>  is well-observed, of course. But we like a challenge.

One thing is having the data on ground - entire world (510,072,000
km²) from Topsat in 2.5m resolution will have ~ 245Tb of uncompressed
data (you'll get to about 1/3 of that if you discard imagery with just
sea), which is lot, but perhaps still manageable. But you have to
either store some non-trivial part of it on the satellite (that is not
as easy as on earth where you can buy some server with RAID and plug
it into wall) while the satellite does not have direct visibility of
the earth contyrol center where it can relay stored images (and then
you have some means to transmit large amount of the data while the
satellite flies over the earth control center) or have multiple ground
stations or bunch of another satellites that relay the continuously
transmitted data.

Martin