
Should we launch a spacecraft to collect energy? - jlebrech
Should we launch a spacecraft along the same orbit in reverse and collect it in 6 months?<p>it could have a supercapacitor to collect the sun&#x27;s energy and then we could use that to power the earth (or a country&#x27;s) energy needs?<p>how big would it have to be?
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gus_massa
You need a LOT of fuel to make a spacecraft go in the reverse orbit. A LOT!!!
To make hard turns the satellites use the gravity of another planet.

Also, the mass of biggest satellite we can launch now is only about a hundred
tonnes (less than a boing 747), if it goes to a low orbit and it is much
smaller if it has to go higher. With a back of the envelope calculation, you
can store about 6 million batteries there. For comparison, the population of
New York is 8 millions, so you can give them less than a battery to each one
of them.

And increasing the mass of the satellite or the fuel amount, makes the fuel in
the launching rocket much much much bigger.
[https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation](https://en.wikipedia.org/wiki/Tsiolkovsky_rocket_equation)

Perhaps you can try to gain some intuitive idea about satellites playing the
Kerbal Space Program game:
[https://kerbalspaceprogram.com/](https://kerbalspaceprogram.com/) The
simulation is not totally accurate, but it's good enough and there are some
mods to increase realism later.

(It's also not easy to store the energy for 6 months. Try storing a charged
rechargeable battery for 6 month and using it.)

Note: This look like a nice question for [https://what-
if.xkcd.com/](https://what-if.xkcd.com/) You can try submitting it there.

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HerpDerpLerp
I am not sure that smashing a supercapacitor (whatever that is) into the earth
at twice orbital velocity will really do that much to help anything...

You could put a solar collector into earth's orbit so it would always be in
the sunshine and <transfer the energy in some way>. However no one has a way
of making this seem economic.

[https://en.wikipedia.org/wiki/Space-
based_solar_power](https://en.wikipedia.org/wiki/Space-based_solar_power)

