Magazine | Page 87 of 278 | Astronomy.com

Twice-setting stars

Exoplanets, Planets

Could the hypothetical Planet Nine have altered Neptune’s orbit?

Going for gold

Orion’s sword

Celebrate with Charles

Stellar rhythm

Astrophotography

Memory hooks

Observing, Planets

Venus blazes after sunset

Observing, The Sun

The Sun’s crystal horns

How do professional observatories deal with dew? Do they heat the mirrors and lenses like amateurs do?

In many articles in your magazine, you refer to regions of the sky as being measured in “square degrees.” How exactly is a square degree defined, and how many of them does the sky contain?

Even with some understanding of infinite density, it seems impossible for the enormous mass of the universe to arise from a subatomic particle. How is this possible?