Assuming I have a satellite in a decaying orbit, could I gently release leaflets from my satellite so they were on a near-identical sub-orbital trajectory and have them touch-down safely on the ground (or sea) without being destroyed on re-entry?

Intuitively to me the relatively low cross sectional area a sheet of paper would impose against the air (assuming it would naturally orientate itself edge-ways against the air as this would have the least drag), and its low terminal velocity, it seems to make sense to me that it has a decent chance of reaching the ground?

  • $\begingroup$ Some pilots might be angry if your advertisement for Doritos brand corn chips or whatever got in the way of their flight path-- but I doubt it'd get that far at orbital velocity. Dropping something at orbital velocity then having it slowly decay to the surface is different than dropping something with no orbital velocity and letting it fall to Earth (but I've never done, or seen, the calculations for a piece of paper). Welcome to the SE though. $\endgroup$ – Magic Octopus Urn Oct 4 '18 at 14:11
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    $\begingroup$ If the satellite has leaflets to drop, you went to all the work to put them in orbit in the first place. Why would you want to do this in the first place? $\endgroup$ – David Thornley Oct 4 '18 at 17:46
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    $\begingroup$ This is not as implausible as it sounds, as JAXA approved a feasability study for a paper airplane experiment although it doesn't appear to have ever actually been launched. $\endgroup$ – TemporalWolf Oct 4 '18 at 18:18
  • $\begingroup$ @DavidThornley for the street cred it will bring me in the next secret "evil genius/marketing consultant" annual conference. $\endgroup$ – Trotski94 Oct 6 '18 at 9:41
  • $\begingroup$ Leaflets released at orbital velocity would still have to shed their velocity to reach the ground. That shedding happens through friction. Since the heat capacity of paper is so low, there's no chance it would survive re-entry. $\endgroup$ – RickNZ Oct 7 '18 at 22:20

If you could engineer your leaflets to fly edge on, perfectly straight and that is enough to enable the paper to survive re-entry. That very engineering would make the landing... Dramatic.

Traditional images of shuttle re-entry show it's belly immersed in flames as it hurtles through the upper atmosphere. However the air is incredibly thin up there, so thin that friction from the air could not generate the heat we see. So whats going on?

Turns out most of the heating space craft experience on re-entry is caused by a shock wave. The small amount of air the craft does interact with transfers huge amounts of energy that forms into a wave traveling with the craft and heating all the air it interacts with.

Space craft have to withstand temperatures surpassing 3000 degrees Fahrenheit to safely re-enter, the flash point (temperature at which something catches fire and burns on its own) of paper is 451 degrees Fahrenheit.

Let's assume we've found a way to keep out paper travelling edge first and this is enough to reduce the heating. What next?

Well we've got a hyper-sonic, incredibly low drag object travelling directly towards the ground. Presuming you planned your marketing campaign right, you've targeted a populated area with potentially kilograms of leaflets.

We've designed them so they wont slow down, what we have here is not a clever marketing campaign, what we have are Rods From God. Weapons of Mass Destruction, at these speeds it doesn't matter that they are made of paper, all that matters is mass.

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    $\begingroup$ Speaking as an evil genius/marketing consultant, either eventuality is fine honestly. $\endgroup$ – Trotski94 Oct 4 '18 at 15:17
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    $\begingroup$ Apparently the last thing to go through your head would be, quite literally, "BUY THIS!" $\endgroup$ – Magic Octopus Urn Oct 4 '18 at 16:27
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    $\begingroup$ I think this ignores (perhaps at the OPs suggestion) the idea that a leaflet has a very low weight to surface area if it is tumbling (which I would say it almost certainly would be) and would be rapidly decelerated... whether that would be enough to not combust is sort of the crux of the issue. $\endgroup$ – TemporalWolf Oct 4 '18 at 17:36
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    $\begingroup$ This answer seems to completely ignore the intuitive sense that a piece of power will slow down (and perhaps survive?) in a way that a space shuttle will not. Now maybe the intuition is completely wrong, and a piece of paper smacks into the atmosphere and burns up, but just assuming one way or the other seems inadequate to me. Anybody know what happens to a parachute dropped into re-entry with no load attached? $\endgroup$ – mbrig Oct 4 '18 at 17:46
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    $\begingroup$ @marcelm en.wikipedia.org/wiki/Fahrenheit_451 $\endgroup$ – uhoh Oct 4 '18 at 19:13

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