space travel Definition and Topics - 27 Discussions

Space-A travel is a means by which members of United States Uniformed Services (United States Military, reservists and retirees, United States Department of Defense civilian personnel under certain circumstances), and these groups' family members, are permitted to travel on aircraft under the jurisdiction of the United States Department of Defense when excess capability allows.

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  1. O

    B Untraditional Space Travel

    If an infinite amount of energy were available to create the lift mechanism for a space launch. What would be required to fire a 200lb object into low earth orbit(160km) after speeding it up in a way similar to how the large hadron collider speeds up a particle. Assuming the launch vehicle...
  2. M

    NASA Which of these methods is the best bet for space propulsion?

    1.) Ion drive 2.) Black hole starship 3.) Fusion Rocket 4.) Fission sail 5.) Halo drive 6.) Horizon drive 7.) Pitch drive, Diametric drive, Disjunction drive...
  3. M

    Which of these methods of propulsion is “best” for future spaceflight?

    Summary: Which of these hypothetical propulsion methods is the best for a spacecraft during Interplanetary flight? Let’s just assume all at this point are cost-effective at the time. Consider the •Safety of the engine •The speed •The efficiency 1.) Monoatomic hydrogen propulsion 2.)...
  4. ckirmser

    Could a <1g acceleration vehicle escape Earth's gravity well

    Hello, all - A question has come back to tickle my brain. Could a vehicle with less than 1G of thrust manage to escape the Earth's gravity well? I'm thinking something like Space X's Falcon 9. As it landed, with just a little more thrust, it could go back up again, I would guess. So, if it...
  5. N

    On board a laser powered solar sail

    Can an on board laser be used to propel a solar sail space craft if the laser is pointed at the sails ? Would Newtons third law affect the laser and maybe prevent the ship from moving ? Thank you for answering my very ignorant questions. NineNinjas911
  6. P

    Limits to accelerate a spacecraft by spinning it in a circle

    The basic concept is to have your space probe(s) - likely nanocraft [1] on a spinning object in space which allows you to preserve the momentum you give it while accelerating it faster. Then once you are at a speed you can simply release the nanocraft in the direction you want it to go in. More...
  7. BTA

    Why would aliens come here? (resurrected)

    I asked myself this question today, found that exact question asked here (February 10, 2005)... and I could not say anything, not even a squeak. Well, boil that dustmote! "Why would aliens come here?" I ask and the voices in my head speak. We are far from the galactic center of an average...
  8. M

    B Could this FTL idea with a fast moving large mass be possibl

    Could this FTL idea with a fast moving large mass be possible? I have recently come up with a possible way to achieve faster-than-light (FTL) travel by using a high speed singularity or large mass. Background As everyone knows, according to relativity, under normal conditions, it is impossible...
  9. L

    The unsolved engineering of the "Space Ladder"

    Spent several hours reading about the approaches and methodology of engineering the conceptual idea of a space ladder. I had no idea it was such a relevant project still. I had a few thoughts on it though: 1. In every proposal it seems the objective was to build a "connect a here to b up...
  10. LaurelAnnyse

    Futuristic Space Travel

    Yeah, pretty much what the title says. Who has cool ideas for the future of space travel?
  11. LaurelAnnyse

    Questions about space travel

    Hey there! My name is Laurel, and I'm working on a short story with a friend about, among other thing, space travel. I've just got some questions about exiting the atmosphere in order to fly a spaceship around looking for other stuff. I don't want you to feel you have to over simplify things...
  12. Ranvir

    B Why is interstellar travel so hopelessly difficult?

    So, I have been thinking about TRAPPIST-1 and how far away that system is from us. It is 40ly away from Earth, according to our frame of reference. This is often put in a way that makes one think that even at speeds close to that of light, it will take almost 40 years to get there. The muons in...
  13. R

    Light beam propulsion without lasers?

    We now have the capability to do laser launch. The problem is the initial cost outlay for the lasers is still prohibitive to launch a sizable payload. The estimate of the payload you can launch to Earth orbit dependent on laser power is about 1 kg per megawatt. So to launch thousand kilo...
  14. A

    B Material for black hole travel

    So I have been watching COSMOS of late and in the 4th (I think) episode it states the possibility that other universes exist inside of black holes. I am aware of the immense strength of a black hole's gravitational pull so my question is this: Is there a material strong enough to resist it and...
  15. allister109

    B Does water pressure decrease in zero gravity?

    me and my friend were talking on facebook and we couldn't think of an answer to the question, would water pressure decrease in zero G, you can see how far along we got before getting stuck in the picture below
  16. Stefen

    B Da Vinci's flying machine meets solar sail?

    so the question has been previously answered as to what would happen if a fan was in the vacuum of space. but the responses I seen all ask what the fan would push on or up against. what if the fan where to push against light? solar sails are able to have a force push against them in space?
  17. J

    I Time Dilation Calculation

    This sounds like a homework question, but I promise you it's not (I'm not even a student). To be honest, the question is simply for my own personal curiosity, to test a theory about a video game. My question is this: If an astronaut traveled for 15 years (their time) at twice the speed of...
  18. DHF

    Writing: Input Wanted Designing a space ship and need help with the dust shield

    Hello everyone, I am designing a ship for my sci fi story and I need input regarding the shield. I am trying to make my story as hard sci fi as I can get away with. The story takes place a few centuries from now and details the first expedition to Alpha Centuri. The ship will have a cruising...
  19. R

    About the resupply missions in "The Martian"

    Two instances were discussed in the film where unmanned cargo ships were mentioned to send up supplies to extend the time Whatney or the crew of the Hermes could survive. This brought back painful memories while watching the movie. It's such an obvious answer. In the space shuttle Columbia...
  20. mileymo

    Relative time in space

    What speed does a ship travelling through deep space need to travel at for 1 day on the ship to equal 1 day on earth?
  21. mileymo

    Travel at light speed

    How long/what distance would it take a spaceship (with a hypothetical propellant-less engine) to accelerate to near light speed, and secondly, how low long/what distance would it take to decelerate back to zero again?
  22. Z

    Building an Ion-thruster

    Would it be possible to build an approximately 10x10x10 cm ion-engine to put on a cube sattelite? I am a university student, so we have a lot of tools, but not a lot of money. What do I need to consider and how much would it cost?
  23. U

    Novel idea for space travel (launch track around the moon)

    What if we built an electromagnetic track around the circumference of the moon? We could then accelerate a spacecraft to a very high speed. In theory it would only be limited by the strength of the materials holding the craft to the track and the centripetal acceleration that the craft/people...
  24. Quotidian

    Earth-Like Planet orbits Sun-Like Star

    That, anyway, is the headline in today's news, regarding the interesting discovery announced by NASA overnight of the planet dubbed Kepler-452b. As I understand it, the properties of the planet are inferred from spectral analysis of its effects on the light from the star which it orbits...
  25. DHF

    Need help figuring out a possible fusion engine

    Hello, I am in the process of writing space based sci fi novella, I made a few posts last year and earlier this year regarding different aspects of the ship and crew. If anyone is interested, I wanted to concentrate on the fusion engine of the ship itself and hopefully come up with a feasible...
  26. P

    What would it be like to be at a Lagrange Point?

    According to this NASA factsheet ( [Broken]) on the Space Launch System (SLS), NASA identifies missions to a Lagrange point as a possibility. From what I understand, a Lagrange point is simply a point where the gravitational fields of two...
  27. D

    Centrifugal Spaceship Accelerator

    Suppose we launch two ships and move them close to the Sun. They have solar collectors and can absorb a massive amount of energy thanks to their proximity to the Sun. The ships are connected by a 1000 meter long rod of titanium, and each ship's rocket is position opposite the other's, so that...