Space Exploration Stack Exchange
Space Exploration Stack Exchange

Questions tagged [physics]

How physics applies to a particular activity in space or to getting to and from space.

A branch of science that deals with all matter and energy. Physics includes mechanics, heat, light and other radiation, sound, electricity, magnetism, the structure of atoms, and more.

346 questions
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What is measured with g-forces?

When sitting at rest, a typical "g-meter" shows a value of one, however the meter is not accelerating. In orbit, it shows zero, but is under constant acceleration. The actual force of gravity in both situations is almost identical, so what exactly…
Innovine
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What powers an e-sail?

We've seen a lot lately about light sails, but this article talks about an "e-sail" that gets pushed along by radio waves. The article says that the idea is for a "sail" that is an electric field generated by the spacecraft itself. Author Michael…
J.D. Ray
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How would gravity/acceleration be perceived by a human orbiting Earth at sea level?

I understand the impracticalities of this concept, but humor the 'what-ifs.' Ignoring physical obstacles and the effects of atmospheric fluctuations affecting the trajectory. Say it is possible to have a craft capable of orbiting in Earth's…
anon
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Can a space craft realistically eject flares to evade a missile?

I was watching Behind Enemy Lines, and one of my favourite scenes is the jet attempting to evade the missiles. All this got me thinking about the Defiant from Deep Space Nine, and some research shows it doesn't have flares for defensive purposes.…
user44102
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Can anyone recommend a good online calculator for travel time within the solar system?

I'm trying to figure out how long it would take to travel to saturn with a skyhook launch from moon orbit.
billy
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What exactly is eLISA, how will it benefit from LISA Pathfinder and how large will it be?

This answer to What do the gravitational wave findings mean for Evolved Laser Interferometer Space Antenna satellite says: Given that the LPF is already launched, I doubt that it will be cancelled. I expect quite the contrary, eLISA is a perfect…
uhoh
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How to calculate mechanical stress on certain parts of rockets?

I'm not very proficient at aero- or fluidynamics or stress calculations, but I want to know how to calculate the stress on parts of a given rocket, given the height(or air density), orientation and velocity vector of said rocket. For example one…
JustAGuy
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Would hypothetical aliens from super-earths be larger and stronger then humans?

I’m curious how physics would affect the size and strength of human like aliens on super-earth worlds with 1 to 2 times the gravity of earth compared to humans. Would they be similar or be larger or smaller then humans based on the physics of their…
Niknik
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Can I do "car surfing" on empty space?

Suppose a Car/Van is launched into space with you. Suppose you would like to do 'Surf' on the car roof like Marty in "Teen Wolf". On the earth, if car accelerate up to 30-50 or 100 mph will make Marty fall down because of air friction and because…
stighy
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