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Like the Soyuz or Apollo spacecrafts, the crew module detaches itself from the service module during re-entry, is it possible to cover the total space-craft with a sleek-aerodynamic heat shield at the time of re-entry thus preventing the addition of space-debris and making the spacecraft reusable up to a certain extent.

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    $\begingroup$ When a Soyuz reenters, the 2 modules that aren't shielded burn up in the atmosphere. The same is done for other spacecraft, so no space debris is created by reentry. $\endgroup$ – Hobbes Aug 16 '17 at 17:09
  • $\begingroup$ Weren't Vostok reentry capsules shielded from all sides about equally? $\endgroup$ – SF. Aug 16 '17 at 17:14
  • $\begingroup$ @Hobbes I see, but what about the re-usability of the spacecraft. $\endgroup$ – Ajinkya Naik Aug 16 '17 at 17:15
  • $\begingroup$ @SF. I dont know....they might have been. So then they must be re-usable too, or are there any other factors besides the disintegration of service module during re-entry that renders a space-craft to be not reusable. $\endgroup$ – Ajinkya Naik Aug 16 '17 at 17:16
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    $\begingroup$ Never mind the Shuttle taught us lessons on costs of refurbishing, tests, and maintenance of the craft. Instead of planned savings, it created monumental costs - not only lifting all the dead weight made the launch stack enormous, refurbishing that for re-launch cost more than building a non-reusable vehicle would. $\endgroup$ – SF. Aug 16 '17 at 17:26
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It certainly is possible to have enough of the spacecraft shielded to have it all land; that's what the Space Shuttle was designed for. However, if you want to be able to land with a heat shield, you must first get it into space to begin with. The heat shielding for the Apollo Command Module has a density of 32 pounds per cubic foot. In total, the heat shielding alone weighed about 3,000 pounds. Now, if you want to reuse your entire spacecraft, the whole thing would have to be covered in heat shielding, increasing your weight by several thousand pounds, depending on its size. That means that you're going to need more fuel in order to get it up there, greatly increasing the mission's cost. In space exploration, every gram counts and is carefully considered. It's much easier to leave a part of your spacecraft in orbit, to be dealt with later.

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  • $\begingroup$ but then the space shuttle was a lot bigger than these spacecrafts, but still it was carried away by a pair of boosters and three liquid fuelled engines, wouldnt it make much difference if we covered the whole spacecraft with a heat shield, wouldnt it be much economical than the space shuttle. $\endgroup$ – Ajinkya Naik Aug 16 '17 at 17:12
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    $\begingroup$ You have to understand what the purposes of different spacecraft are. The Soyuz capsules are just meant to send personnel and supplies to the ISS whereas the Space Shuttle was meant for astronauts to live in and conduct experiments, so it had to be much larger. $\endgroup$ – Phiteros Aug 16 '17 at 17:14
  • $\begingroup$ i think your comment is not related with mine, the space-shuttle even if much larger than these small space-crafts was covered completely with heat shields and was still re-usable, then these space-crafts being smaller in size would be much more economical to cover with a heat shield. $\endgroup$ – Ajinkya Naik Aug 16 '17 at 17:19
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    $\begingroup$ But the point is that it's not worth fully covering them in a heat shield. Especially since you still need to service and replace the heat shield after every use. You must also take into consideration the shape of the spacecraft. It needs to be aerodynamic and designed to get through the atmosphere. If it isn't already shaped like that, then you'll also have to put more time, money, and resources into redesigning it. $\endgroup$ – Phiteros Aug 16 '17 at 17:20
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    $\begingroup$ The space shuttle returns from low earth orbit, whereas the Apollo capsule returns from a Lunar Return Trajectory. A lot more kinetic energy in the later example, thus more ablative material required. $\endgroup$ – Sarah Bailey Aug 16 '17 at 17:26

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