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40

Not much research has been done on this question in recent years, but some researchers are worried enough to research into wooden satellites. The question on the environmental impact of deorbiting satellites burning up in the upper atmosphere was partly addressed in a 1994 report (warning: not peer reviewed) by the Environmental Management of the Space & ...


32

The mass of Earth's atmosphere is 5E+18 kg and the Troposphere alone has 3/4's of that. With an average height of 13 km that makes its volume $4 \pi r^2 h$ or about 6.6E+18 m^3. If we break up one thousand 100 kg satellites into semi-porous PM2.5 particles that works out to be 1.5E-08 micrograms per cubic meter, and we generally worry about tens of ...


8

Probably not. To control the point of reentry, you need to be able to adjust from a perigee high enough to not promptly reenter (i.e. above 200km) to one low enough to promptly reenter (i.e. below 80km) in significantly less than the time it takes to complete a single orbit -- otherwise, the unpredictable effects of drag in the variable density upper ...


4

The question is not flawed - radiating heat away requires no medium. This NASA Tech Brief (NTRS ID: 19750000042) and many other sources give the maximum temperature of the high-temperature, reusable surface insulation (HRSI) tiles as 2300°F (1543 K). I also found this dated website from Purdue that claims a maximum single use temperature of 2800°F (1810 K). ...


4

A controlled reentry comes at a cost. China and SpaceX are apparently betting that the added cost of a controlled reentry vastly outweighs the cost of debris from an uncontrolled reentry resulting in significant damage. Suppose a chunk of debris kills a cow. Nobody will have a cow over this. People will have a cow if a chunk of debris kills a person. But ...


1

The premise of this question is flawed First stages do not reach orbit, they are suborbital and fly on ballistic trajectories. So the question has never arisen at least up until now. It is theoretically possible to build a single stage to orbit vehicle and the Lockheed X33 experimental vehicle almost made it but was cancelled prior to being tested. https://...


1

I have read the answers about deorbiting second/upper stage […] do people still care about intentionally deorbiting the first stage It doesn't matter whether it is a first stage, second stage, third stage, fourth stage, kick stage, space tug, satellite dispenser, satellite, space station, tank, or something else entirely. It is not a good idea to have ...


1

Neither NASA nor Xinhua news, in their detailed descriptions of the overall mission, mention any role for the orbiter after the returner separates from it in Earth orbit to land. Any extended mission for the orbiter that requires equipment beyond what is needed to retrieve Lunar samples would have eaten into the payload budget and probably reduced the size ...


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