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The answer would have to be best scientific guess or theory, rather than fact, but has any thought been given to what actually happens to the metallic elements of a spacecraft de-orbited into Jupiter?

I'm looking for scientific thought, speculation or simulation that I can read about.

See "Why destroy Juno at the end of the mission?" and all answers, including this one.

I assume it is going fast, and "burns-up", but what might happen to the metallic atoms? Aluminum, Copper, Iron... would they form compounds in the atmosphere that are heavy and slowly (very slowly) sink to the core, or happily remain as atmospheric trace compounds at the (quite high) altitude where the disintegration took place, or something else?

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    $\begingroup$ It's only just arriving and the questions here are all about its end of life, so sad ;-( $\endgroup$ – gerrit Jul 6 '16 at 10:07
  • $\begingroup$ @gerrit Oh it's not so many! In the last four days there are eight questions with [juno] tags, only two of them about that. You can search by putting [juno] in the search box (the square brackets make it a tag search) and then sort by newest. See here. In the previous month or so there are even more non-end-of-life questions. Actually, it's a happy thing - it's better to be responsible about our potential bacteria and spores and viruses and make sure we don't contaminate anything. $\endgroup$ – uhoh Jul 6 '16 at 15:40
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Juno will burn up in the atmosphere, and very violently so (over 40km/s of reentry speed vs Earth's 8; effects scale quadratically), so it will dissipate as trace contamination of the atmosphere, spread to four winds through Jupiter's violent weather.

If (dubiously so) any solid pieces survive, they'd sink to the surface of solid hydrogen layer and rest on it (like things rest on the sea bottom).

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  • $\begingroup$ Wow! 40km/s - ya it seems safe to say it will vaporize while still at the "top" of the atmosphere. I'm trying to figure out if the metal atoms that are spread out will react with the atmosphere and make heavy molecules that will sink individually because they are heavy, or say aloft and slowly mix. $\endgroup$ – uhoh Jul 6 '16 at 7:28
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    $\begingroup$ @uhoh: in fact, likely more. "Low Jupiter Orbit" is 42km/s. I don't know what orbit Juno will operate on, but likely a highly eccentric one, with periapsis velocity much higher than that. $\endgroup$ – SF. Jul 6 '16 at 7:48
  • $\begingroup$ For a ~14 day orbit, I get a semi-major axis of about 1.65 million km. If the periapsis - oops, I mean perijove is about 5000km above the surface, I get about 57 km/sec! $\endgroup$ – uhoh Jul 7 '16 at 5:28
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    $\begingroup$ @Uhoh: So, on Earth, a kilogram of spacecraft has 32MJ of kinetic energy to dissipate. Juno - 1.6GJ. $\endgroup$ – SF. Jul 7 '16 at 6:03

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