Ask a Spaceman!

What happens to a white dwarf when it cools off? How long does it take? Do they just stay ... more

How did we discover the weak nuclear force? Why is it so strange compared to the other for... more

Is the universe infinite? What about the cosmological horizons, the limits to what we can ... more

Why did we develop the International Space Station in the first place? What have we learne... more

How do particle colliders work? What kinds of energies are we talking about? Are there any... more

What are some sources of gravitational waves that aren't black holes? How did inflation cr... more

How do we measure the sizes of stars? What are the biggest ones today, and how big could s... more

What powers Cepheid variable stars? What about Mira variables and pulsating stars? And are... more

What would the Sun sound like if we could hear it? Does any noise at all happen in the uni... more

Why does the vacuum of spacetime have energy? How much energy does it have? What prevents ... more

How do we actually define voids? Are there regions within them that are truly empty? What ... more

Part 2 of 2! What are the modern constants of nature? Is the universe fine-tuned for life?... more

Part 1 of 2! How do fundamental constants appear in physics? Why are they so important? Wh... more

What's inside a neutron star? What strange states of matter do we encounter? And what myst... more

How do we explain the giant black holes appearing in the young universe? Is it possible to... more

How do you measure the impact of a scientist? Does Stephen Hawking compare to Newton or Ei... more

Why is the moon so special? Why do we think a giant impact created it? Why didn't the same... more

What is 21-cm radiation? What (and who) produces it? What causes it, and what does it tell... more

What is an Alcubierre warp drive? What would it take to make it work? Could it propel spac... more

What is an axion? How could axions make a star, and what does that have to do with dark ma... more

Where do parallel universes exist? Could we use wormholes to travel to them? What does tim... more

What is the Fermi Paradox? How rare is non-intelligent vs intelligent life? What are the c... more

Are dark photons as sinister as they sound? What did the curvaton do in the early universe... more

How can the solar corona be hotter than the surface? What has the Parker Solar probe learn... more

Are we "in range" of any potential supernovae? Has the Earth ever been hit in the past? An... more

How do black holes get close enough to merge? What causes them to emit gravitational waves... more

How did Pluto get demoted? What makes a planet a planet anyway? Why do we now have so many... more