1. [Updated]How fast is the force of gravity?
2. [Updated]What does the inside of an electron look like?
3. How do sound waves travel through outer space?

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4. If I point my laser pointer at the Moon, why don't I see a spot?
5. How does it feel to be weightless?
6. How long can a person survive at 95 and 105 degrees F?
7. Where do the neutrinos go that are made by humans?
8. On which asteroids could you jump into orbit?
9. Is the photon that reaches your eye from a distant galaxy the very same one that started its journey across intergalactic space?
10. How the ding dang was the Astronomical Unit determined?
11. What is the difference between a gamma-ray and a cosmic ray?
12. If you took a vacuum cleaner into space, what would happen?
13. Is there really sound in space?
14. What is a plasma?
15. If scientists always seem to be 'proving wrong' the current favorite theory, what is the point of all this research if in the end we never establish anything as being True?

1. [Updated]What is anti-matter?
2. [Updated]Does gravity produce gravity?
3. [Updated]Can gravity be shielded?
4. [Updated]Why is the sky blue?
5. [Updated]Are photons, gravitons and neutrinos really massless?
6. [Updated]Has the decay of the proton been detected yet?
7. [Updated]What is the coldest temperature recorded in space or in nature?
8. [Updated]Exactly what is gravity?
9. [Updated]What is hyperspace?
10. [Updated]What is time?
11. [Updated]What is the 'darkness' that you see between the stars in the sky?

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12. What is energy?
13. How much of a charge excess would be needed in the universe to produce detectable non-gravitational motions?
14. When two laser beams interfere with each other, what happens to the energy?
15. Does everything in the universe consist of energy?
16. If the force of gravity were reduced 50 percent, how would this change stars and the universe?
17. Does time stop at Absolute Zero?
18. What do absolute space and time mean?
19. Does light have anything to do with the 5th dimension?
20. Could you give a technical explanation of the 'Slingshot' maneuver?
21. Do other dimensions exist?
22. What happens to matter at Absolute Zero?
23. How are tachyons supposed to work?
24. What is a boson?
25. How does the gravitational 'slingshot' maneuver work?
26. Can sub-atomic particles be infinitely compressed?
27. Is the empty space inside particles the same kind as there is inside atoms?
28. What would the predicted properties of Element 115 be?
29. At what distance from the Earth do astronauts experience weightlessness?
30. Are quarks really considered fundamental particles?
31. What does it mean to travel to another dimension?
32. Does anti-matter fall faster than normal matter?
33. Are quarks really the smallest particles next to electrons?
34. Is there any evidence that the Laws of Nature change over time, or in different regions of the universe?
35. Is anti-gravity possible?
36. Is there an Absolute Highest Temperature opposite to Absolute Zero?
37. Does data ever become obsolete before it can be properly interpreted?
38. How close can the moon come to the earth before disrupting?
39. Can radioactive decay be influenced by exposure to oscillating electromagnetic fields?
40. Can gravity be simulated using electromagnetic forces?
41. Can astronomers tell whether stars and galaxies are made of anti-matter?
42. Are there any particles smaller than quarks inside quarks?
43. Will the laws of physics change in the future?
44. Why is physics so complicated?
45. How do you reconcile Zeno's paradox with modern physics?
46. Why was there a slight imbalance between matter and antimatter just after the Big Bang?
47. How is a stellar parallax used to determine the distance to stars?
48. How is it possible for physicists to slow light down to 38 miles/hour?
49. Is there such a things as 'pure energy'?
50. What is 'quantum foam'?
51. Why do we need a Unified Theory of Everything?
52. Will Theory of Everything predict exactly what will happen tomorrow?
53. How would the existence of a 4th neutrino affect cosmology?
54. Why does mathematics work so well in understanding the physical world?
55. What are the '10 dimensions' that physicists are always talking about?
56. Is light conducted by space, or does it travel through it?
57. Is there anything that is 'something' that is not matter?
58. In which part of the electromagnetic spectrum is the sky brightest?
59. How can one particle emit enough gravitons...or whatever...to affect all other particles in the universe?

1. [Updated]Why do bodies have gravitational fields?
2. [Updated]Would space be totally empty and non-existent without virtual particles?
3. [Updated]What exactly is Zero-Point energy?
4. [Updated]What exactly is the Higgs field supposed to be?
5. [Updated]What is the Casimir Effect?
6. [Updated]What is hyperspace?
7. [Updated]Given that the vacuum is filled with virtual quantum particles, is there really such a thing as Nothingness?
8. [Updated]What will the Theory of Everything do for astronomy?
9. [Updated]How do lightning storms produce x-rays and gamma-rays?
10. [Updated]Where do cosmic rays come from?
11. [Updated]Does anti-matter fall faster than ordinary matter?
12. [Updated]What is the most energetic form of light that astronomers have ever seen?
seen?
13. Is the blue color of a flame caused by continuum or line emission?
14. What is a cosmic string?
15. How are tachyons supposed to work?
16. What exactly is a sub-atomic particles structure like?
17. How is Zeno's Paradox resolved in physics?
18. What is Grand Unification Theory?

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19. Does the physical vacuum produce a pressure that can be measured?
20. Are all particles and fields just vibrations in an energy field?
21. How does the size of a crater depend on the size of the meteorite?
22. What is the Roche Limit and who discovered it?
23. What is the role of time in the so-called Theory of Everything?
24. Where does the energy come from that produces virtual particles?
25. Can the structure we see in the physical world be simply a projection of how our brains work?
26. What is infinity?
27. So, is Schroedinger's cat alive or dead?
28. How does energy flow in those other dimensions to space-time outside the standard four?
29. Are quantum uncertainty and the existence of compact dimensions to space-time related?
30. Is there a 'smallest possible size' to space beyond which it cannot be further divided?
31. How do you calculate centrifugal forces in a rotating space station?
32. Can electrons really be in two places at once?
33. How did 'hidden variables' theory get put to rest in quantum mechanics?
34. Could you tell me what the arrows of time are in relation to cosmology?
35. Can virtual particles still be created in a vacuum where the temperature is absolute zero?
36. What are the 'infinities' that physicists keep finding in their theories?
37. What are the main ideas behind superstring theory?

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