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Black Holes

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Resources for this Topic

  1. How Do We See Black Holes? (

  2. Virtual Tripto a Black Hole (

  3. Black Hole Frequently Asked Questions (

  4. Usenet Physics Frequently Asked Questions List (

  5. Imagine the Universe! Black Holes

Library of Past Questions and Answers

    Common Questions about Black Holes
  1. How many black holes are currently known?

  2. Where is, and how far is the nearest known Black Hole?

  3. Is it true that time stops at the Event Horizon?

  4. If light has no mass, how can it get trapped in a Black Hole?

  5. Will black holes consume everything in the universe?

  6. Will the Large Hadron Collider produce Earth-destroying black holes?

  7. Could the Big Bang have been a Black/White Hole?

  8. Are black holes flat?

  9. Do white holes exist?

  10. Could Black Holes be connected to White Holes?

  11. Can black holes/worm holes transport you to other worlds?

    Evidence for Black Holes
  1. Who was the first person to discover a black hole and what was the date?

  2. How has it been demonstrated that black holes are real?

  3. Have X-rays been used to confirm the existence of black holes?

  4. What evidence is there for a black hole at the center of our Galaxy?

  5. What is known about Sagittarius A*, the center of our galaxy?

    Black Hole Appearance

  1. Are there any pictures of black holes or of the edge of the Universe?

  2. How would a black hole look, if one came in front of a star field?

  3. What is the volume of a black hole?

  4. How does a black hole move through Spacetime?

  5. Could there be more than four dimensions in a Black Hole?

  6. What is the difference between stellar and galactic black holes?

  7. What properties define a black hole?

  8. How could I model a black hole for a science project?

    Pulled in by a Black Hole?

  1. What would happen to Earth's orbit if the Sun became a black hole?

  2. How can a black hole only 2 to 3 kilometers big eat a star?

  3. What happens when you orbit a black hole outside the Event Horizon or fall into a black hole?

  4. What would happen if a black hole passed through a star?

  5. What would happen if a star were launched into a black hole?

  6. Do black holes ever collide?

  7. What would happen if two Black Holes merged?

    Inside a Black Hole

  1. What happens to the material absorbed into black holes?

  2. What is the name for the center of a black hole?

  3. Is the singularity in M87 the same volume as a stellar one?

  4. What happens to the accreted matter once it has collapsed into the singularity?

  5. How can a Black Hole have zero volume and infinite density?

  6. How can a black holes singularity have zero volume?

  7. When light enters a black hole does it curve or is it bent?

  8. If time comes to a standstill in a black hole, where does time began again out side the black hole?

    Light and Matter from Black Holes including Hawking Radiation

  1. How do black holes emit X-rays?

  2. Why does accretion of matter onto black holes make them luminous?

  3. Is it possible that high speed (close to c) particles are flying around a neutron star/black hole?

  4. Why are there bipolar jets associated with black holes?

  5. Can black holes be used as a power source?

  6. Are there any sub-atomic particles that are able to escape a hole's event horizon?

  7. How is it possible for black holes to emit matter even if their gravity field is so intense?

  8. Will black holes evaporate?

  9. Can you explain Hawking Radiation in more detail?

  10. What is the temperature of a black hole?

    Formation of Black Holes

  1. How are black holes formed by supernovae?

  2. What force causes the compression of matter to a singularity?

  3. Can black holes be formed from lower mass stars?

  4. Are supermassive black holes and host galaxy sizes related?

  5. How are medium sized Black Holes formed?

    Black Holes and Gravity

  1. What is gravity's effect on itself?

  2. Does the gravitational field of a black hole pull objects in faster than the speed of light?

  3. What is Quantum Gravity and how does it relate to Black Holes?

  4. How does gravity escape from black holes?

    Advanced Concepts
  1. What are the meaning of the letters in the "BKZS Limit"?

  2. Can you explain what a Kerr Black Hole is?

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