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NASA proposed a policy for the jettison of trash from the ISS space station.

This article notes that a recent ISS space station spacewalk by Russian cosmonauts involved one man jettisoning by hand a replaced electronics pack. The pack was shoved by arm and hand downwards to Earth. See the link to a YouTube video showing the dramatic toss.

How much time and distance does that package take to fall before disintegrating/burning-up?

Also: Is the point of burning-up too far to see the flare by camera from the space station?

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    $\begingroup$ Why instead of putting a link to the youtube video in the article you put a link to a crackpot lecture? $\endgroup$ – OON Mar 9 '18 at 8:32
  • $\begingroup$ could you perhaps provide the relevant time of the video? $\endgroup$ – Everyday Astronaut Mar 9 '18 at 8:32
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    $\begingroup$ @derwodamaso: Problem solved. $\endgroup$ – Nathan Tuggy Mar 9 '18 at 8:33
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Citing NASA's FAQ on orbital debris

The higher the altitude, the longer the orbital debris will typically remain in Earth orbit. Debris left in orbits below 370 miles (600 km) normally fall back to Earth within several years. At altitudes of 500 miles (800 km), the time for orbital decay is often measured in decades. Above 620 miles (1,000 km), orbital debris normally will continue circling Earth for a century or more.

The space station orbits at around 400 km altitude, so that would fall into the category "several years". The part was tossed backwards w.r.t. the station, which increases the rate of decay.

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    $\begingroup$ In the video it looks like it was thrown more retrograde than "downwards" this deorbits it quicker than throwing it downwards iirc. $\endgroup$ – Dragongeek Mar 9 '18 at 9:21
  • $\begingroup$ @Dragongeek right, corrected that $\endgroup$ – Everyday Astronaut Mar 9 '18 at 11:06
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    $\begingroup$ Also, throwing it backwards, with drag reduces the chances that it's orbit will take it back into collision with the ISS. Throwing it straight down virtually guarantees that it will eventually reconnect with the ISS. $\endgroup$ – RBarryYoung Jun 21 '18 at 19:31
  • $\begingroup$ 400 km is actually more of a "Several months" as opposed to years. Trash is light and not very aerodynamic, it should have a higher drag then the space station. Not sure exactly, but most likely a year tops. $\endgroup$ – PearsonArtPhoto Aug 24 '18 at 17:47
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It depends

The ballistic coefficient of the thrown object will vary and that what's going to set the rate of decay.

There is two factors to that coefficient:

  • The surface area of the trash
  • The mass of the object

Few years ago a cosmonaut threw an USB key from the ISS. It was wrapped in a plastic bag to increase the surface and the rate of decay. See video.

One last thing: The astronauts don't throw the objects towards nadir (down), they throw objects retrograde (towards the rear). This will in turns slow the orbit of the trash and ensure there is sufficient horizontal separation when the object gets back again on the next orbit (minus orbital decay).

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  • $\begingroup$ Nice pointing out the dependencies. Minor remark: NASA's FAQ does not mention these dependencies, thus I guess the stated estimates apply either generally or for the most common types of debris. $\endgroup$ – Everyday Astronaut Mar 9 '18 at 11:11
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    $\begingroup$ The CBM "taco" corner shield that was lost last year on EVA took a little less than a year to reenter. Being made mostly of foam and fabric, it had a very low ballistic coefficient, though. $\endgroup$ – Tristan Mar 9 '18 at 15:17
  • $\begingroup$ @uhoh While I am aware your question was intended as humor, the answer is actually interesting. To quote the linked article: The memory stick in question contained videos and scripts from last year’s 70th anniversary celebration of the Victory Day in Russia. This event commemorated the 70th anniversary of the capitulation of Nazi Germany in 1945, and was the largest and most lavish celebration ever held in Russian history. $\endgroup$ – Basil Bourque Aug 24 '18 at 20:54
  • $\begingroup$ @BasilBourque Thank you for clearing that up, and for reminding me to take advantage of links provided. $\endgroup$ – uhoh Aug 25 '18 at 1:06

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