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Is it possible to release an object from a space station (say the ISS) to make it continue out into the solar system? The most intuitive answer to me (a non-physicist) would be yes, you are in space, there is little gravity, so if you release something directly "upwards," away from Earth, it will continue until space dust slows it down or something else (like Jupiter) consumes it. However, on space stations orbiting the Earth, weightlessness is just an illusion, and in reality the station falls towards the Earth, creating the circular motion. Furthermore, a very specific speed is required to orbit at a specific distance. Hence the answer might be more complicated; it might start orbiting the Earth instead. Will an object released directly "upwards" from the ISS (with minimal force) really continue out into the solar system?

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  • $\begingroup$ I've deleted some comments that shouldn't have been posted as comments, and their responses. Remember that the comment section is not meant for discussions. $\endgroup$ – David Z Sep 14 '15 at 4:46
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Download the *.pdf (orbit.pdf) embedded in this link for a full derivation (dragless) for a very similar problem as asked in the question.

In it, an object is thrown from the International Space Station (ISS) towards the Earth at $1 \text{ m/s}$. The conclusion is that the object enters a new, eccentric orbit, barely $1 \text{ km}$ below the orbit of the space station (its orbital radius is about $6800 \text{ km}$).

Throwing something from the ISS to hit Earth is a lot harder than you might think.

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  • $\begingroup$ But if you aimed a bit backwards, it should be possible to hit the Earth, right? $\endgroup$ – Gaussler Sep 13 '15 at 19:48
  • $\begingroup$ @Gaussler: I believe so. $\endgroup$ – Gert Sep 13 '15 at 19:50
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    $\begingroup$ "aiming" backward is insufficient. You have to have sufficient velocity change to drop the lower end of the orbit to the earths' surface. $1m/s$ isn't enough to do that in any direction from ISS. $\endgroup$ – BowlOfRed Sep 14 '15 at 2:44
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During my A-levels I had a small difference of opinion on this with my lecturer - he stated that any shove away from a stable orbit would cause the object to escape altogether.. I countered that the object would experience an 'orbital wobble' and just settle back down again to a circular orbit in the future (like Saturns rings I thought)..

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    $\begingroup$ Why should it settle down? Elliptical orbits are stable too. Bizarre that your lecturer would say that, it's pretty clueless for a teacher to just ignore the role of energy. $\endgroup$ – Blackbody Blacklight Sep 14 '15 at 2:04

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