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-6
votes
1answer
59 views

Would this ship travel faster than light [on hold]

Im curious about using a geometric thruster system to break the speed of light barrier, Using a system of beams that rotate along alternating axis' from either end of themselves so as to travel a ...
0
votes
1answer
45 views

How do gravitational sling shots work? [duplicate]

How can an object move faster after leaving the gravity of a planet, should a gain in potential energy by moving away from the planet lead to a loss of kinetic energy? Or am I missing something ...
8
votes
3answers
109 views

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 ...
0
votes
1answer
33 views

law of conservation of linear momentum (Nuclear Engine)

Suppose there is a isolated system in which there is only one stationary rocket. As the rocket is in stationary position the initial momentum will be 0, now nuclear engine is started, as a result ...
1
vote
0answers
42 views

Space travel and time dilation

I want to know how long it takes, from an observer in a spaceship moving at constant velocity $v=\beta c$, to cover a distance $d$. From a stationnary observer outside, the spaceship goes at a ...
0
votes
1answer
60 views

Could vacuum chambers lighten the load for space bound technology?

Would cavities of near vacuums in the head (or in the 6 x 6 blocks surrounding the rocket [for reentry temperatures]) of a rocket make it lighter so it can be sent out easier?
1
vote
1answer
33 views

Does increasing the energy of a relativistic particle increase thrust?

I know this particular chestnut has been asked before, but I have a specific variation on the theme: Particle accelerator space thrust. Specifically, cyclotrons to generate the thrust. They are ideal ...
1
vote
2answers
69 views

Magnetism In Space

I am not an expert when it comes to physics. I was looking at maglev technology the other day and a thought crossed my mind. Would similar systems work for deep space exploration. I understand ...
0
votes
1answer
53 views

How do they know their velocity in a spaceship? [closed]

Suppose a spaceship is going to Mars or to Jupiter, they switch on their thrusters and accelerate for a certain period, how to they know their position / velocity, do they refer to the Sun?
3
votes
3answers
107 views

What the live streaming of a time traveler will look like?

Consider a hypothetical situation: In which a time traveler travels in a spaceplane at close to speed of light circling the earth and I get a live telecast of inside of that plane to my television. ...
2
votes
3answers
83 views

Is it possible to travel near light speed and not notice relativity?

Suppose I have no idea about relativity and find an ancient spaceship that takes me to Proxima Centauri in just 1 year more than it takes light to make the trip (so some observer might say it took ...
0
votes
0answers
100 views

Will future spaceships for very long distance rotate?

I have seen in the movie Interstellar and The Martian they use the model of spaceship which rotate around it's axis. This is the spaceship model from Interstellar. This is spaceship model from The ...
3
votes
2answers
55 views

Where is the space elevator falling? And the cable holding it?

I guess the concept of a space elevator is pretty well known. The idea, first published by Konstantin Tsiolkovsky in 1895, and popularized (among others) by Arthur C. Clarke in The Fountains of ...
0
votes
0answers
64 views

If humanity was to send a probe to Proxima Centauri, how long would the travel last?

If humanity was to send a probe to the nearest star: Proxima Centauri, at a distance of 4.24 light years from our sun, what would be the optimal propulsion technology to reach the destination as soon ...
6
votes
1answer
106 views

Do stray photons become interstellar daggers to a space traveler near the speed of light?

Suppose I am traveling through space, accelerating closer and closer to the speed of light. As I speed up, photons traveling towards me become blue-shifted to higher and higher frequencies. When I am ...
0
votes
2answers
152 views

Gravitational Time Dilation vs Acceleration Time Dilation

I might be a little dense to this subject, but I would like to ask a question relating to this one ( Is gravitational time dilation different from other forms of time dilation? ) but asking if this ...
0
votes
0answers
47 views

What Would One Observe of a Calendar on Earth, Given a Round Trip to Another Star and back?

I want to ask a clarifying series of questions on what I think is a relatively simple scenario. It's a long one but I've tried to word it as simply as I can manage while trying to do the question ...
-1
votes
2answers
68 views

Is there a most efficient speed to travel in space with reference to time dilation? [closed]

I was thinking hypothetically, a ship traveling to a distant star system with something like food wants to get to the system as fast as possible. The trick is, we want to travel as fast as possible in ...
0
votes
1answer
40 views

How much gravity (and/or magnetic field) would a space ship need to generate to hold an atmosphere around it? [duplicate]

Say you wanted a ship to have a bubble of atmosphere around it, 800m in diameter with the ship at the center. What sort of gravity (and perhaps magnetic field) would be needed? Would either of these ...
4
votes
2answers
168 views

What will happen to a human being exposed to Martian atmosphere?

Mark Watney, in the movie The Martian, says that, If the HAB breaches, I'm just gonna, kind of... implode. The corresponding novel, by Andy Weir, says he will explode (as pointed out by @...
-6
votes
1answer
74 views

How can we see the alien, who are travelling in light speed? [closed]

If aliens has the technology to travel in speed of light ,How can we see them with our 'below the speed of light' technology?. Because when we see that(!),definitely it will not be in its place.Is ...
0
votes
1answer
68 views

Reading about liquid propellant rocket design

I was reading NASA's manual on liquid propellant rocket design from 1971. It makes the following statement. The rocket or, in a more general sense, the reaction motor presently is the only ...
0
votes
1answer
66 views

Time relativity

Lets say that I am on a spaceship moving with the speed of 0,90c and I am looking on my friend who stayed back on earth. My friend is looking on me. From my perspective, my friend is moving 7 times ...
1
vote
1answer
51 views

Humans on earth seen from traveling space ship

If I would stand on a space ship traveling with a speed of 0,99c I would be moving 7 times slower from Earth's perspective. But if I would look back on Earth I would see everything moving 7 times ...
3
votes
2answers
168 views

Why is an Alcubierre drive shaped like it is

When I look up the Alcubierre drive I keep seeing that the drive powering the bubble is shaped like a circle - is this necessary for the creating of the "warp bubble" that travels forward? Does the ...
0
votes
1answer
113 views

How do spacecraft gain kinetic energy by passing near planets? [duplicate]

When a a spacecraft like Voyager travels close to Jupiter, it somehow gains kinetic energy. I'm not sure how this energy isn't simply lost again as it moves away from Jupiter. I'm also hoping this ...
2
votes
0answers
70 views

What's the fastest you can slingshot from one black hole to another? [closed]

Let's say you have your spaceship orbiting around a black hole. Its orbital velocity is arbitrarily close to the speed of light (or you can just set it to c*0.99 if it makes it easier.) There is ...
0
votes
2answers
131 views

Is it possible to reach outer space with this method? [duplicate]

Could we use a hot air balloon to carry a rocket and send it into orbit at a higher altitude? That is, do I need to reach a specific speed to be completely free of Earth's gravity, or can I just ...
4
votes
2answers
1k views

How does a spacecraft enter Earth's atmosphere?

If Earth whirls around the center of our galaxy at some 220 kilometers per second, how can a spacecraft, which is much slower, enter Earth's atmosphere when returning from Mars for example?
1
vote
1answer
200 views

Traveling faster than the universe is expanding?

I was thinking, if the universe is space and time expanding, lets say in 3D (like a sphere). And it is doing that in a constant or not constant speed, there is a debate about that, never mind that but ...
1
vote
3answers
154 views

What sort of propulsion technology would allow spaceships to lift off the surface of the Earth and ascend into space like we see in sci-fi movies?

In many sci-fi films, spacecraft are easily capable of lifting off the surface of a planet like a Harrier and ascending into space. It's clear that the propulsion system/jet engines aren't your ...
0
votes
0answers
90 views

How realistic is a “bolas” system for artificial gravity in space travel?

The spinning space-station is very popular in sci-fi as a means of emulating gravity in space. But it requires rather a large diameter to minimise "gravitational gradient" effects and that means such ...
2
votes
2answers
60 views

Does the microgravity environment in highly elliptical orbits differ from circular orbits?

I think everyone understands the microgravity environment broadcast from the ISS. But the ISS stays in a fairly circular orbit, the acceleration of gravity should be fairly uniform, the altitude and ...
0
votes
0answers
255 views

The effect of multiple Alcubierre rings

In all of the descriptions and visualizations I've ever seen of the Alcubierre drive but one, it takes the form of a single ring or toroid surrounding a spherical volume of flat space. The exception ...
93
votes
6answers
10k views

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 ...
20
votes
4answers
3k views

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 ...
1
vote
1answer
85 views

If there were intelligent life in another galaxy, would we notice? [closed]

I've read that once intelligent life successfully achieves interstellar travel, it could populate the galaxy in tens of millions of years, likely populating the most habitable planets and preventing ...
0
votes
1answer
166 views

How much energy would it require to send Earth to Proxima Centauri?

Assuming 100% efficiency of energy usage, and given the current estimates about the mass of known objects in our solar system, including Earth itself, and assuming no other objects are affected by ...
1
vote
0answers
37 views

Modeling atmospheric reentry with respect to the rotation of a planet and its atmosphere in a simulation

I am creating a hard science fiction flight simulator. I am a civil engineering student, so its a little out of my area of study. Currently I model air resistance on the velocity difference between ...
2
votes
2answers
58 views

How can solar sails be maneuvered?

Photons from the Sun are always radial to it and hence solar sails can only travel radially. Any techniques related to maneuvering?
2
votes
1answer
55 views

Does the payload of an Alcubierre drive have to be on board during the preparation phase?

I was thinking about the practical aspect of using an Alcubierre drive, assuming one existed. I'm no expert, but my understanding is that, since the destination has to be in the forward light-cone of ...
-1
votes
1answer
68 views

What size astroblaster would be required to shoot a man to the moon (as alternative to rocket propulsion systems)?

Accord. to my Prof. a 92 astroblaster would be sufficient to shot a ball to the moon. I have done some research on the internet, but could not find any sufficient source. Does anyone know about ...
2
votes
0answers
66 views

What does it look when we travel at the speed of light? [closed]

Suppose we're in a spaceship or in a car which runs at the speed of light. We are watching the light which is coming towards eyes at the speed of the light. What would it look like when the driver ...
0
votes
1answer
29 views

If we are traveling to Mars in Hibernation State [closed]

If we are traveling to Mars in Hibernation State with artificial gravity. Which hibernation position of our body is the best i.e. lie flat or stand up, considering making bone loss as less as possible....
3
votes
1answer
169 views

Why does the Cassini probe experience jerky acceleration in deep space?

I was looking at this plot of speed over time for the Cassini probe. What's going on at the right, after mid-2004? Why does it keep slowing down and speeding up again?
7
votes
1answer
1k views

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 ...
1
vote
1answer
3k views

Questions after watching the movie Interstellar [closed]

Awesome movie, but as a physics student, some questions do crop up When they travel to the watery planet, they say that 1 hour on this planet is 7 yrs om earth. How is this possible? Is the planet ...
0
votes
0answers
40 views

Why are centrifuge space-station designs not a reality? [duplicate]

Considering how useful it could be for the crew of a space station to have at their disposal a 1g environment (or more) at the rim to a 0g environment at the axis of rotation, why aren't modern space ...
2
votes
2answers
145 views

How is strong time dilation consistent with weak tidal forces?

Nolan's latest film, Interstellar, takes pains to explain to lay audience members that the passage of time slows in the presence of strong gravitational fields (as per Einstein's theory of General ...
3
votes
1answer
345 views

Burning fuel in space while accelerating and deaccelerating

Is it true that for acceleration in space we need not the same quantity of the fuel than during the deacceleration stage?