Category Archives: Astronomy

The 2012 Venus transit

Physicist: There wasn’t a question behind this, but it’s worth announcing. On June 5th or 6th (depending on where you are in the world) Venus will pass directly between the Sun and the Earth, so it’s basically a solar eclipse, … Continue reading

Posted in -- By the Physicist, Astronomy, Experiments | 4 Comments

Q: Why haven’t we discovered Earth-like planets yet?

Physicist: It’s amazing that we’ve found any at all, considering the difficulties involved. The scale of things in space is ridiculous.  The closest discovered planet to us, outside of our solar system, is “Epsilon Eridani b“, a mere stone’s throw … Continue reading

Posted in -- By the Physicist, Astronomy | 4 Comments

Q: What would happen if a black hole passed through our solar system?

Astronomer: Most black holes form when a star which is ten times more massive than our Sun runs out of fuel for fusion. This causes the star to collapse, explode as a supernova, and, if enough material is left over … Continue reading

Posted in -- Guest Author, Astronomy, Paranoia, Physics | 81 Comments

Q: Why does gravity make some things orbit and some things fall?

Physicist: This subtlety was one of the great insights of Newton; that the “falling apples” force and the “circling planets” force are one and the same. Whether gravity pulls an object into orbit or just “makes it fall” depends on … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 15 Comments

Q: How does the expansion of space affect the things that inhabit that space? Are atoms, people, stars, and everything else getting bigger too?

Physicist: Way back in the day Edwin Hubble (of telescope fame) noticed that the farther away a galaxy is, the faster it’s moving away from us.  From this he figured out that the universe is expanding, but in a very … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 31 Comments

Q: What would Earth be like if it didn’t turn?

Physicist: The side of the Earth facing the sun would quickly become hotter than boiling water, and the side facing away would be cold enough for the atmosphere to freeze solid (condense into nitrogen and oxygen ice).  So all of … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 21 Comments