Magazine

Science

In my astronomy studies decades ago, we used the “Roche limit” to determine when a smaller body is too close to survive a larger object’s gravitational force. Do astronomers still use that term?

Astrophotography

Using masks, part 2

Exotic Objects

Web Extra: Exploring the pulsar zoo

Stars

Web Extra: What about Eta Carinae?

Exotic Objects

Why do we see a flash instead of a constant signal from a millisecond pulsar, which spins 20-700 times per second? Is that not fast enough to maintain a steady beam of light?

Solar System

Web Extra: A comet’s nucleus laid bare

Astrophotography

Using masks, part 1

Cosmology

What is polarization? What does it have to do with the cosmic microwave background?

Astrophotography

Creating unresolved stars

Cosmology

Is the universe depressed?

Exotic Objects, Stars

Web Extra: Listen to two supernova songs

Exotic Objects, Stars

A recent study found that a type Ia supernova’s original star could be anywhere from 0.9 to 1.4 times our Sun’s mass. Astronomers use these blasts’ brightnesses to estimate distances, so are those measurements now incorrect?