Category Archives: Astronomy

Proxima B!

Physicist: Good news!  There’s an Earth-sized planet in the habitable zone of Proxima Centauri, a star so named because it’s the closest star to Earth and it’s in the constellation Centarus.  This isn’t a question anyone asked, but I thought … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 13 Comments

Q: Is there anything unique about our solar system?

Physicist: Maybe. As far as stars go, ours is a dull as dishwater, middle of the road, dime a dozen, main sequence star.  You can’t spit in space without hitting a Sun-like star.  So this question is really about the … Continue reading

Posted in -- By the Physicist, Astronomy, Philosophical | 5 Comments

Q: What is dark energy?

Physicist: The universe is expanding and the rate of that expansion is accelerating.  If the universe were full of only matter (both regular and dark) and energy, then we’d expect that the expansion would be slowing.  Dark energy is the … Continue reading

Posted in -- By the Physicist, Astronomy, Physics, Relativity | 28 Comments

Q: Is geocentrism really so wrong? Is the Sun being at the “center” (i.e. the Earth orbiting the Sun) just an arbitrary reference frame decision, and no more true than the Earth being at the center?

Physicist: When you walk around in this big crazy world, there aren’t any immediate reasons to suspect that the ground under your feet is doing anything more than sitting perfectly still (ring of fire notwithstanding).  Given that, when you look … Continue reading

Posted in -- By the Physicist, Astronomy, Experiments, Physics, Relativity | 13 Comments

Q: Why is our Moon drifting away while Mars’ moons are falling?

The original question was: I know the Moon is getting further away because tides/friction/conservation of angular momentum.  This video claims Phobos is getting closer to Mars because of tidal forces, what gives?  Obviously no oceans to drag around but what … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 11 Comments

Q: What is the state of matter in deep space?

The original question was: What might be the state of matter in [interstellar space]. Average temperature is 2.7K , so all the gases like hydrogen, helium should be in liquid or solid state? Physicist: Matter in deep space tends to take … Continue reading

Posted in -- By the Physicist, Astronomy, Physics | 11 Comments