Questions tagged [escape-velocity]
The speed needed to "break free" of the gravitational attraction of a body without spending more propellant.
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How much bigger could Earth be, before rockets wouldn't work?
hint: Apparently the Tsiolkovsky rocket equation does not actually say that you can launch a conventional rocket into orbit around an arbitrarily large and massive body.
I'm looking for a number ...
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Why did Voyager 2's velocity drop far below escape velocity before the first gravity assist?
As per @kasperd's comment on another question.
Looking at the graph below, it appears that Voyager 2 started at just over escape velocity of the solar system. Just before the Jupiter flyby, it was ...
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Couldn't I escape Earth's gravity traveling only 1 mph (0.45 m/s)?
It is said that in order for an object or a projectile to leave Earth's gravitational pull, it must reach Earth's escape velocity, meaning reach a speed of 7 miles per second (~11 km per second). Well,...
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How much Delta-V would be required to escape the Gravitational Influence of the Earth without entering orbit?
As impractical as it sounds (and it's definitely impractical) I was wondering what the Delta-V required to leave Earth's influence would look like if we launched "just straight up" into the Earths ...
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Could a Human reach escape velocity by jumping from the surface of Ceres (a dwarf planet)?
According to this answer the surface gravity of Ceres is estimated to be only $0.27 m/s^2$. With a rotation period of 9 hours. The gravity seems light enough to overcome by leg muscle alone, and if ...
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Could a human jump off Mimas without return?
A similar question has already been asked on dwarf planet Ceres:
Could a Human reach escape velocity by jumping from the surface of Ceres (a dwarf planet)?
Ceres has 2.9% of Earth's gravity. Saturn's ...
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Why is it easier to escape the solar system than get to Mercury or the Sun?
It has been mentioned several times on this site that it is "easier" (less delta-v, and hence less fuel) to reach the escape velocity of the solar system, than to reach the planet Mercury or ...
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Why not travel to Mars in 2 months?
Just to clarify: I've made some research and generally know what the case is, didn't mean to make the question sound stupid. :)
I know there is a thing called Hohmann transfer orbit, named after ...
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How many times do you have to circle the Earth to break orbit?
My science teacher asked us this, and nobody in my class knew. We guessed it would be three, but with no evidence.
(Edit: The asker has not returned to clarify if they meant leaving the Earth-Moon ...
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Largest radius sphere with Earth's surface gravity on which you could jump at escape velocity? Bigger than B612?
In the book Le Petit Prince by "French aristocrat, writer, poet, and pioneering aviator Antoine de Saint-Exupéry" the main character lives on an extremely tiny asteroid with the name B612. It is this "...
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Apollo 11 mission report shows velocity well below escape velocity thousands of km on the way to the Moon
This is from the Apollo 11 mission report. It says the vehicle was going at 7.6 km/s when the CSM separated from the third stage. It was not in orbit at this point, it was thousands of KM from earth.
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Is space travel possible from a large planet? [duplicate]
I was playing with a rocket design simulator, and I noticed that if I set Earth's gravity to be much higher than it is today, it became impossible to design a rocket that could reach escape velocity.
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Has any human had the capability of leaving the Solar System?
Inspired by Has any human ever had the choice to leave Earth permanently? and the answers and comments there, has any human had the capability of leaving the Solar System?
I'm thinking of Apollo ...
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Has any human ever had the choice to leave Earth permanently?
Far beneath the ship / The world is mourning
They don't realize / He's alive
No one understands
But Major Tom sees / "Now the light commands
This is my home / I'm coming home."
Peter ...
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What is the escape-velocity for our galaxy?
What should be the escape velocity for our galaxy and can we calculate it?
For instance, if we assume that we don't know the mass of our galaxy, you may consider it as small 'm'.
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What is the most fuel efficient way out of the Solar System?
I understand with current technology we can't just fly a straight line out of the solar system but which way out would need the least fuel?
Currently to navigate the solar system it is a dance ...
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Is there a theoretical limit to the size of launch vehicles?
Is there a limit to the size (mass, structural issues) of boosters that can be launched either to orbital or escape velocity? I am asking about such constraints as the required thrust to weight ratio ...
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Is non-evacuated tube maglev launch possible? [duplicate]
I heard about evacuated tube transportation technology and it's application to launch cargo or even shuttles to space. Example of such project would be StarTram.
The fact that acceleration phase to ...
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Why is it so hard to build crewed rockets/spacecraft able to reach escape velocity?
Why are we still not going farther than to Low Earth Orbit? Orbital velocity is about 4.8 mi/s (7.7 km/s) and escape velocity is about 7 mi/s (11.2 km/s), about 45% faster. Why is it so hard to reach ...
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How fast is fuel escaping a rocket for it to reach the escape velocity 11 km/s?
I was having a discussion with a person and we were talking about whether or no the fuel had to be pushing out of a rocket at 11 km/s in order for the rocket to reach 11 km/s.
I said it has to be ...
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what happens to particles that escape the atmosphere on planets in the solar system?
What happens to particles that escape the atmosphere of planets? (not just earth).
Do they eventually form a uniform distribution of particles overtime? Do they inevitably to fall into the ...
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Are there any accurate velocity plots of all spacecraft that achieved escape velocity from the solar system? (Pioneers, Voyagers, & New Horizons)
The answer to this question provides a seemingly accurate plot of the velocity of Voyager 2 over distance along with the heliocentric escape velocity.
Are there similar graphs for the other 4 ...
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How do we come up with the gravity assist (or slingshot) formula?
When you search up in google gravity assist formula, it comes up with the simplest version:
Which means that: Final velocity = Initial velocity + 2 (velocity of the planet)
Then if we do some more ...
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What factors determine how long a window of opportunity opens for an interplanetary hohmann transfer?
I know that one can determine the approximate wait time for a window of opportunity to open up for an interplanetary transfer based on the relative positions and velocities of the two planets in ...
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Laniakea Delta-V and Escape Velocity
We live in the Laniakea supercluster. Galaxies including the Milky Way are being pulled toward the "Great Attractor" in its center.
Two questions (note that the answer to one can be used to derive ...
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How much thrust to launch a regulation size FIFA soccerball into orbit
How much thrust is necessary to launch a regulation size FIFA soccer ball into orbit around the Earth? Let us assume a size 5 which weighs between 420g and 450g. Remember, we will need thrust to ...
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What's the escape velocity at the near/far end of Phobos considering tidal forces?
At the Roche limit tidal forces disintegrate bodies. A rock or a human would just float away from the points nearest/farthest from Mars. The tidal forces must be higher for rigid bodies than rubble ...
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Bucket loop between Earth and Moon?
Please don't bite my head off. If this is so stupid that it deserves to be squashed, I'm quite happy to delete the question. I mainly would like to know whether anyone's ever suggested this (I ...
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Could escape velocity be achieved in the atmosphere?
When rockets launch for orbit they travel up and the air thins respectively to the speed increasing.
How fast can a rocket for travel at sea level before it would fail or the elevation would have to ...
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Would it be possible to go beyond Jupiter without making any slingshot?
It is said that we do not have such advanced technology in order to send a spacecraft out of the solar system. (Source: Everyone around)
When a spacecraft is launched from Earth and aims to leave the ...
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Can I avoid a magnetar with an electromagnet?
Magnetars are generally accepted as existing. Wikipedia suggests that the magnetic forces are strong enough to kill you.
I am assuming that virtually any spacecraft would have some magnetic ...
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Astrophysics on "The Martian"
In the movie the martian what was the purpose of the hermes crew in blasting a part of the ship?
Was that explosion on the front or back of the ship?
After the explosion what happened to the speed ...
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What is the maximum orbital speed beyond which the orbit around any large object in the Solar System becomes unstable?
How fast is too fast to stay in orbit around any particular large body in the Solar System?
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Did a spacecraft ever use an atmosphere to accelerate away from a planet?
If a spacecraft enters flat enough into the Earth's (or another planet's) atmosphere it will "bounce off" the Earth at a higher speed. That method can be used if a spacecraft has not enough fuel to ...
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Neutrinos travel faster than the speed of light [closed]
If neutrinos travel faster than the speed of light does the calculation for the speed of light become obsolete. IE is there now a new formula for calculating speed/velocity through space/vacuum.
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