Posts by 

Christopher Crockett

What are white dwarf stars? How do they form?

A white dwarf is the incredibly dense core of a dead star, left behind when the star exhausted its fuel. Our sun will become a white dwarf one day.

What are coronal mass ejections? Strong eruptions on the sun

Coronal mass ejections (CMEs) are powerful eruptions on the sun that can disrupt electrical systems and produce brilliant auroral displays on Earth.

What is the zodiac? Why is it important in astronomy?

Maybe you associate the word "zodiac" with astrology, but it has an honored place in astronomy, too. It's defined by the annual path of the sun across our sky.

What do redshifts tell astronomers?

Redshifts reveal how an object is moving in space, showing otherwise-invisible planets and the movements of galaxies, and the beginnings of our universe.

What is a parsec?

Why do professional astronomers speak of distances in the universe not in terms of light-years, but in terms of parsecs, a distance of 3.26 light-years? Explanation here.

The ecliptic is the path of the sun

The ecliptic is an imaginary line that marks the path of the sun. You can also find the planets and moon near this line, tracing the plane of our solar system.

What are gamma ray bursts?

Only the most powerful explosions in the universe.

What is a light-year?

Hint: A light-year is a unit of distance, not time.

What are elliptical galaxies?

Elliptical galaxies are among the largest single star systems in the universe and are built by the collisions of many smaller galaxies.

What lives between the stars?

The interstellar medium is the stuff between the stars. Made up mostly of hydrogen and helium gas, it contains all the material needed to make stars and planets. It is shaped by stellar winds, dying stars, galactic magnetic fields, and supernova explosions.

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