Space Exploration Stack Exchange
Space Exploration Stack Exchange

Questions tagged [gravity]

Questions regarding the attractive force present between two masses. If about research in artificial gravity (i.e. manmade substitutes for gravity), please use the artificial-gravity tag.

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Is there a term for the distance from an object at which it's gravitational pull is negligible?

I used to think that there was a point at which you escaped the Earth's gravitational pull. This is technically false, since every object in the universe is attracted towards every other object. Is there a term for the point at which we consider it…
Premier Bromanov
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Could an Earth volcano impart escape velocity on lightweight matter?

When a big volcano erupts like Krakatoa or Mt St Helens does it send steam, smoke, dust, rocks high enough and fast enough to escape Earth? Could any lightweight matter from a volcano actually get enough of a push to escape into outer space?
Rose White
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Would a person exposed to zero gravity for a long time have trouble riding a bicycle?

I just watched this video by Drew Feustel showing him having trouble walking upright after 197 days on ISS: https://mobile.twitter.com/Astro_Feustel/status/1075889929119547393 They say once you have learned how to ride a bicycle you can never…
Quassnoi
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Does living in space affect humans' strength?

I am an enthusiast of space exploration. Is it possible that strength of a human can be increased or decreased by keeping them in microgravity? From this link. Astronauts can become as weak as 80-year-olds after six months at the International…
Mr_Green
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Is there really no difference between up and down in ISS?

ISS is actionally falling towards the earth and therefor they don't feel gravity. But ISS is falling in a direction towards the earth. So the astronauts living in ISS probably live in ISS in a manner which would be directed how ISS is organised. All…
Marijn
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Do knots behave any differently in zero gravity?

What happens to knots in zero gravity? Do they behave any differently? I've tried to do some reading on it, but I can't find anything related to knots in zero gravity.
LLLK7
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Objects speeding up due to planets gravity?

I remember hearing that asteroids and other objects can actually gain speed while passing a planet or large object to due the gravity, but still not enter orbit. Is this true? If so, how is this possible? I'm asking because the phenomenon could be…
Skyler 440
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Would more or less gravity make you proportionately stronger?

It is known you can lift more if gravity is weakened, but more weighs less in less gravity. Though what is the ratio compare to normal gravity...like if you can lift 100% of your body weight in a gravity level of 1 how much weight can you lift in…
CrandellWS
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why dose reentry speed need to be so fast

I have been wondering this since I was a kid. watching films of capsules and shuttles heating up and all that tile trouble and work that went into all. I would always wonder why they dont slow down before entering the atmosphere.
John Schossow
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How microgravity in space affects body parts

There are things that naturally face downwards, like hands. How would they be affected in space microgravity? Would they rise or point downwards?
griffins
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Would a mouse trap snap faster or slower in space than on Earth?

Would a spring loaded mechanism outside a spacecraft activate a lever faster or slower in space with no atmosphere and gravity than on Earth? Basically this is in reference to mechanical instruments or devices that are spring loaded and not for…
Autodidact
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Question about variation of Law of Gravitation

In the book, Fundamentals of Astrodynamics, the author provides a different form of the Law of Gravitation $$\ F_g = - \frac {GMm} {r^2} \frac {\mathbf r}{r} $$ So the book says that the ${\mathbf r} $ is the distance vector, but what does that make…
user78103
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Can a smart phone function in space?

I recenty came a across a doubt... Can a smart phone be used in space? Obviously you aren't going to get any data signal, but will the functions like touch screen, GPS, accelerometer, vibrator, etc, work? Will anything get affected by gravity or no…
SidS
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Gravitational potential

I understand how we calculate gravitational potential and how we set it to be zero at infinity, and I understand its value at he Earth's surface is $-64\,\mathrm{MJ/kg}$ by using $r$ as Earth's radius. However, how is it we can escape the earth's…
James Oconnell
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What keeps galaxies together?

The super massive black hole at the centre of Milky Way has a mass of about 4 million times that of our sun. Is this enough to keep the entire galaxy together, is it this black hole which keeps the galaxy together? I did read that there are also…
O S
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