Questions tagged [space-travel]
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Why do spaceships heat up when entering earth but not when exiting?
Recently I read up on spacecrafts entering earth using a heat shield. However, when exiting the Earth's atmosphere, it does not heat up, so it does not need a heat shield at that point of time yet. ...
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Could we send a man safely to the Moon in a rocket without knowledge of general relativity?
I'm wondering if it's possible to send a man to the Moon using equations consistent with Newtonian gravity and without the elaborate tools of Einstein gravity. Are the predictions made by Newtonian ...
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Where does the extra kinetic energy come from in a gravitational slingshot?
I read in this answer in this site that the KE a free-falling ball acquires is not originated by the attracting body but that energy was actually stored in the ball when it had been lifted to the ...
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If I'm floating in space and I turn on a flashlight, will I accelerate?
Photons have no mass but they can push things, as evidenced by laser propulsion.
Can photons push the source which is emitting them? If yes, will a more intense flashlight accelerate me more? Does ...
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Is it possible to send all nuclear waste on Earth to the Sun?
If we neglect the danger of unsuccessful lift-off of the rocket and the cost, would it be physically possible to send all nuclear waste on Earth to the Sun?
Will there be an obstacle that prevents ...
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How long would it take me to travel to a distant star?
Suppose I wanted to travel to one of the recently discovered potentially Earth-like planets such as Kepler 186f that is 490 light years away. Assuming I had a powerful rocket and enough fuel, how long ...
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Could someone jump from the international space station and live?
Felix Baumgartner just completed his breathtaking free-fall skydiving jump from $120,000\,\text{feet} = 39\,\text{km}$ above the Earth, breaking the speed of sound during the process.
I was wondering ...
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Why don't modern spacecraft use nuclear power?
The Voyager 1 & 2 spacecraft launched in 1977 with Plutonium as their source of electricity. 34 years later they claim these two spacecraft have enough power to last them until at least 2020. That ...
John Conde
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Parker Solar Probe passing extremely close to the Sun; what relativistic effects will it experience and how large will they be?
note: This is a question about relativistic effects. I've included some detail about the spacecraft and its orbit for background, but the question is about relativistic effects and their observability....
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Why don’t astronauts “push” spacecraft?
Perhaps it goes without saying, but according to Newton’s laws “every action has an equal and opposite reaction”. How do astronauts, especially those inside small spacecraft like the Crew Dragon, not “...
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How long would a bubble made in the ISS last?
It seems to me that if on Earth soap bubbles pop, it is because the gravity makes the water and soap go to the bottom of it. When there is not enough water at the top of the bubble, it pops.
But ...
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Why is Anti-helium so important in the search for dark matter?
I've been reading/hearing that if the AMS satellite measures a significant flux of anti-helium in cosmic rays, that would be an irrefutable proof of dark matter. I was wondering:
Why is that? what is ...
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How to travel between two stationary worlds in the least amount of time? (time dilation)
Let's imagine there are two, isolated, stationary worlds in space (called A and B), very far apart from each other. I live on World A, and some aliens live on World B.
I want to learn about the ...
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Why is Voyager 1 approaching Earth? [duplicate]
When I read JPL's mission status for Voyager 1 and Voyager 2 the distance between Earth and Voyager 1 is decreasing.
Is it right?
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Would a fast interstellar spaceship benefit from an aerodynamic shape?
Some (generous) assumptions:
We have a spaceship that can reach a reasonable fraction of light speed.
The ship is able to withstand the high energies of matter impacting at that speed.
Given the ...
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Is it possible to sail "close hauled" with a solar sailship?
I have not been able to find a clear or decisive answer about this. On Earth, a ship sails close hauled when the ship is, to some degree or another, facing into the wind. This is made possible with ...
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Cameras in Voyager probes
I've always wondered about the cameras in the space probes, especially in the Voyagers.
1) What kind of cameras do they have? Digital? (Electronic - what kind of sensor and megapixel count?) Analog? (...
Andres
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Why put a radio telescope in space instead on the Moon?
Why are we not building a space-based radio telescope? If a lunar radio telescope is hard to build, why not a space-based radio telescope? It could be an interesting tool, I presume. Thus, what could ...
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Why are spacecraft made to "spin" after launch?
At some point after launch, usually just before or after separation from the last booster stage, spacecraft are often made to "spin" (about the axis of their trajectory)? See e.g this You Tube video. ...
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"To come back to Earth...it can be five times the force of gravity" - video editor's mistake?
I've watched The Truth About Gravity With Professor Jim Al-Khalili | Gravity And Me | Spark where astronaut Chris Hadfield says at 3:55:
To come back to Earth is violent
Then after several seconds ...
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Are the Voyager probes still sending us a signal ?
This article reported today, a finding from one of the voyager probes. It talks about magnetic structures at the (far) outer edge of our solar system. Does that mean we're still able to pick up a ...
giulio
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How would we see a near-lightspeed object emitting light?
Consider an object travelling near the speed of light relative to us (let it be a spaceship or a star), which is emitting light (consider it monochromatic resulting from a two level electronic ...
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Movie Interstellar - Question about Escape Velocity
The movie Interstellar shows people on a water planet where time is dilated so much that 1 hour is equal to 7 years back on Earth. Even though they lift off from Earth using a Saturn-V two stage ...
user32023
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How much damage would a space probe cause?
How much damage would a space probe cause if it can get about 4 lightyears away in 10 years and doesn't have any brakes when it arrives? Could it cause a global extinction event on the planet it was ...
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What is the most distant object from the Earth that a spacecraft has visited to date?
What is the most distant object from the earth that a spacecraft visited has visited so far? What was the mission and when did it happen?
Mehper C. Palavuzlar
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What is the fastest a spacecraft can get using gravity-assist?
Assuming normal spacecraft and space objects (no neutron stars, black holes, etc). To what speed can a spacecraft accelerate using gravity-assist?
For example, if a spacecraft is moving at ...
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How fast would a spaceship have to go to reach Alpha Centauri within a person's lifetime?
Given the recent news about the discovery of an "Earthlike" planet orbiting Alpha Centauri (our nearest stellar neighbour) it got me wondering just how fast would spaceship have to travel to be able ...
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How are interplanetary trajectories found?
How are interplanetary trajectories that involve gravity assist maneuvers found?
Examples:
the MESSENGER spacecraft made flybys of Earth, Venus, and Mercury before getting into orbit
the Juno ...
user921
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Why can't a spaceship accelerate for ever? Since there is no friction in space
I have seen many answers like: because we don't have infinite energy, because of gravity, because it is impossible, because of physics.
But they don't really answer my question.. I mean if there is ...
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Rockets in vacuum vs. Rocket on earth
Recently my physics teacher during a rant said something that piqued my interest. Heres what he said "There are more problems visiting other stars if you wanted a rocket to go 99% the speed of light ...
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The most distant point from the earth that a space shuttle has reached
What is the most distant point from the Earth that a space shuttle has reached? When did this happen?
Mehper C. Palavuzlar
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Voyager: Is it in "orbit" and will it return?
This Phys.SE question about Voyager got me thinking, and I didn't see an answer:
Gravity - what goes up must come down.
Will Voyager, in its current trajectory ever be pulled back into our Solar ...
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Spacetime and its contribution to space science
Does the launching of a satellite need the consideration of the general theory of relativity (GR)?
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Why did the WMAP mission last so much longer than Planck?
NASA endorsed 9 years of data taken with the Wilkinson Microwave Anisotropy Probe (WMAP). The High Frequency Instrument aboard the Planck satellite ran out of coolant at the start of 2012, after about ...
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Would it be possible to create a hadron collider in space?
Would it be theoretically possible to create a hadron collider in space by orbiting particles around a planet?
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Travel duration from Earth to a star at 9.8 m/s² acceleration [duplicate]
How much time would it take for a traveler (in traveler's perspective) to reach a star at distance $d$, if it accelerates at 9.8 m/s² (for a comfortable travel)?
I understand that $V = V_0 + a\times ...
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What Problems for 50 year space probe to Alpha Centauri?
I'm thinking speculatively. NASA is doing experiment with ion thrust tech. Assuming, that inside the next 5 years, we could create a probe which would take on the order of 30 to 50 years to reach ...
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What happened to Apollo's Saturn-third-stage rockets?
I read recently the original Apollo 11 press release and it mentions that the Saturn V's third stage (used for Trans-Lunar Injection) was deployed into a solar orbit of some kind:
(Source: Press Kit -...
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Has a human ever perished in space?
Apollo 13 returned safely. The Challenger was leaving when it exploded. The Columbia was coming back when it burned up, as was that Russian guy who was profiled on National Public Radio (NPR) and that ...
SB01
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Graphene as optical and UV mirrors
One usually hears about graphene as a good thermal conductor, and good light absorber due to its tunable bandgap properties. But i haven't heard about its aplicability as an optical mirror. In fact, ...
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Exoplanet detection via space-based parasol
I remember from watching Cosmos years ago, Carl Sagan suggested an interesting hypothetical method for directly seeing exoplanets. He proposed that in the 'future' we could launch a satellite designed ...
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Antimatter Propulsion System
Is there a possibility ( in theory ) to build a antimatter propulsion system, if so how can we control the collision of matter-anitmatter, will humans be able to control this force just like ...
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Where are the Voyagers going?
Given enough time, where are the Voyager spacecrafts heading? (Assuming some alien civilization doesn't pick them up.)
Will they pass by any interesting stars on the way to the black hole at the ...
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How would one navigate interstellar space?
Headed out from Earth within the Solar System, Sol and Earth both may be used as reference.
When traveling in interstellar space with stellar systems themselves traveling at varying velocities even ...
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How can Voyager 1 escape gravity of moons and planets?
I think this one is pretty simple so excuse me for my ignorance. But since most planets in our solar system are very well tied to their orbit around the sun or orbit around their planet (for moons), I ...
Luca Matteis
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How close can spaceship get to the Sun
If you want to fly a spaceship with human passengers as close to the Sun as possible, then what effects would the spaceship have to be designed to counteract in order to keep the passengers alive and ...
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Where to find information on the pulsar map written to Voyager's golden record?
Where might I find details about the pulsar map written on the Voyager's golden record?
This diagram defines the location of our Sun utilizing 14
pulsars of known directions from our sun. The ...
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Can we make high acceleration safe to our bodies thanks to this gravity trick?
According to Wikipedia, a human body can resist g-force of about $5 g$. It can be a greater value in some circumstances, but even as low as $2 g$ would be unpleasant after several seconds. This means ...
