75 FAQs about Space Travel (The Astronomy Cafe)

NASA's History Archive

Starship Designs

Babylon 5 starship technology

 Back to the Astronomy Cafe - 365 of the most popular questions since 1996. Over 1 million page requests!

 The Science Behind Hyperspace - Why science fact and fiction often don't see eye-to-eye

 Faster Than Light - The many ideas for FTL travel from the science fiction universe

 Hyperspace in Science Fiction - A new way to travel, and the many ways to do so!

 Timeline of the Future - Here is what may be in store for us in the next 100 billion years!

 

So... What's the Real Story?

Even after NASA figures out how to bring down the cost of space travel from $10,000/pound to something more reasonable, the biggest factor limiting our access to space is not a technological problem. It is simply that adults do not see a practical reason for entering space, although many of them may dream of us eventually doing so. We are very quick to come up with money to start wars and make ourselves safe and comfortable, but no nation in existence today would ever consider funding space exploration at the rate we did in the 1960's when we went to the moon. Americans, alone, spend $28 billion a year on garden supplies, and tens of billions on cosmetics and video entertainment. Imagine what we could do, and the places we could go, if we really invested in the high frontier! During the 1960's, NASA's budget was 5% of the American Federal Budget. Today, in 2003, it has fallen to less than 0.7% - nearly a factor of 10 times smaller!!!

 Thanks to extravagant science fiction movies and TV series, we may not actually need to invest in space travel at all. Perhaps the illusion that we are a 'space-faring' civilization in our imagination is really all we were looking for in the first place. It is far more fun to imagine and pretend what aliens might look like, than actually investing in a serious way to really find out. Of course, our laid-back attitude about space may be in for a very rude awakening when that next asteroid enters our atmosphere and destroys a city, state or country. Until then, space is a pretty abstract concept for nearly all of the 6 billion people on this planet. Access to space is only available for a dozen astronauts per year.

Beginner:

  1. [Updated]Could you say more about space junk as an environmental problem?
  2. [Updated]Will humans ever travel to the stars?
  3. [Updated]Will astronauts ever be hit by orbiting debris?
  4. [Updated]What would happen if an astronaut took her glove off for a few seconds in space?
  5. [Updated]Will travel at light speed ever be possible?
  6. [Updated]When do you think humans will set foot on Mars?
  7. [Updated]How long did it take Apollo astronauts to get to the Moon?
  8. [Updated]Why doesn't the Space Shuttle burn up when it reenters the atmosphere?
  9. [Updated]Will commercial 'tourist' space travel ever become practical or possible?
  10. [Updated]How long would it take to reach each planet from the Earth?
  11. [Updated]Is NASA using Ion Power in its new spacecraft?
  12. [Updated]What will space travel be like in the year 2264?
  13. [Updated]What is your main complaint about science fiction in the 21st Century?
  14. [Updated]Why do bones become brittle in space?
  15. [Updated]Why is Space Shuttle computer technology so primitive compared to what I can get at the store?
  16. [Updated]What is all the funny business about spacecraft speeds and relativity?
  17. [Updated]Is NASA working on new propulsion technology to replace rockets?
  18. [Updated]When will NASA develop a true nuclear rocket engine?
  19. [Updated]How fast could we travel in space with existingtechnology?
  20. [Updated]How much has NASA spent on space research and travel?
  21. [Updated]Will NASA ever send a spacecraft to revisit Mercury?
  22. [Updated]How do you explain relativity theory to a 12 year old?
  23. [Updated]Do astronauts need magnetic fields to survive in space?
  24. [Updated]Why does the sky look black from space?
  25. [Updated]Were the Apollo moon landings really a hoax?
  26. Will anyone ever travel to Mars?
  27. How long would it take to get to the nearest star?

  28. Do spiders spin the same kinds of webs in space and on the Earth?
  29. Do you have any references for the physiological effects of human space travel?
  30. Have any man-made objects left the solar system?
  31. What is the probability of humans directly encountering visitors from other worlds?
  32. Did NASA cancel the Space Shuttle mission in April, 1997 because of the solar flare?
  33. How much radiation exposure do astronauts get in space?
  34. Do rocket launches affect the orbit of the Earth?
  35. What are the effects of space on human reproduction?
  36. Are any laboratories trying to develop faster than light travel?
  37. In deep space communication, what data rates are used?
  38. What do astronauts really do in space?
  39. What material is used to make spacecraft?
  40. Why is the velocity of the Voyager spacecraft decreasing as it leaves the solar system?
  41. Could you really hide a starship in a nebula?
  42. Will private enterprise ever become important in space travel and exploration?
  43. How fast does the Space Shuttle have to travel to leave the atmosphere?
  44. Where can I get the latest day-to-day news on the Space Program?
  45. How many plants do you need in a space station to make enough oxygen for one person?
  46. Can the effects of some diseases be reversed or stopped in space?
  47. Where can I get information about what NASA plans to do in the future?
  48. What are the know physical and mental problems with human spaceflight?
  49. Is it possible to reach speeds greater than 100,000 miles per hour in space?
  50. At a speed of 1/8 the speed of light, how long would it take to get to Proxima Centauri?
  51. Can humans be frozen for long voyages like they do in some science fiction stories?
  52. What would happen if I stepped into space without a spacesuit?
  53. Does NASA use magnetic fields to improve astronaut health in space?
  54. What does the atmospheric trajectory of the Space Shuttle look like?
  55. How much do astronauts get paid?
  56. Now that water has been found on the Moon, Mercury and Mars which would be better to colonize?
  57. Why can't we use old ICBMs for space travel?
  58. Is it really scary up in space?
  59. Why do NASA spacecraft have to be so clean?
  60. Why can't NASA sell moon and mars rocks to finance its programs?
  61. Why was the Space Shuttle fuel tank painted red?
  62. Is the space travel described in 'Babylon 5' and 'Star Trek' plausible at all?
  63. How fast does the Space Shuttle travel compared to a bullet?
  64. Other than the Moon and Mars, where else should we put human colonies in the solar system?
  65. Using modern technology, how long would a trip to the nearest star take?
  66. What happens when a human is exposed to a vacuum?

Intermediate:

  1. [Updated]How much younger are astronauts after they return from orbit?
  2. [Updated]Can a spacecraft be rotated to create artificial gravity?
  3. Using solar sails with a 1-G acceleration, how long would it take to get to Jupiter or Pluto?

  4. If cosmic rays are a big problem for travel to Mars, why aren't they a problem for Shuttle astronauts?
  5. At what speed does the interstellar medium become lethal to high speed flight?
  6. How can a continuous 1-G thrust get you to Alpha Centauri without exceeding the speed of light half way there?
  7. Could you travel large distance in space by warping it in some way?
  8. Is the kind of artificial gravity used in Star Trek ever possible?
  9. What is an Alcubierre warp drive?
  10. I don't understand how an Alcubiere space warp can actually let you cross space in a short time?
  11. How do slingshot orbits work?
  12. How is it possible for the Slingshot Effect to extract angular momentum from a planet?
  13. If a spaceship had a constant thrust indefinitely, could it reach light speed?
  14. How feasible is warp drive and matter teleportation in Star Trek?
  15. How does ion propulsion work?
  16. If atoms can be in two places at one time, why can't we use this to travel through space instantly?


Return to Ask the Astronomer