Posts by 

Andy Briggs

Astronomy Essentials

What are red giants?

What are red giants? Most main-sequence stars, like our sun, will become one. Red giants swell to such a large size they can swallow their inner planets.

What is a magnetar?

Magnetic magnetars Can you imagine a magnet so powerful that it could wipe every credit card on Earth from a...

Why does a variable star brighten and dim?

A variable star is one that brightens and dim in a cycle that might last hours, or weeks, or months, or longer. What makes a star change its brightness?

What is a quasar?

A quasar is an extremely bright and distant point-like source visible to radio telescopes. The source is a so-called Active Galactic Nucleus, fueled by a supermassive black hole.

What is the Milky Way?

When someone says "Milky Way," do you think of the starry pathway across our sky, or of the great pinwheel-shaped galaxy in space? Both are correct!

What is a supernova?

A supernova is a star's colossal explosion at the end of its life, potentially outshining its entire galaxy. Read about the causes and types of supernovae here.

What is a galaxy?

We live in a galaxy called the Milky Way. But there is so much more to know about these grand and glorious star islands in space! Click in here, and prepare to have your mind expanded.

What is a globular cluster?

Unlike the open star clusters - containing sibling stars, scattered through the disk of our galaxy and presumably other galaxies - globular clusters are big, symmetrical and old, like an earthly city's oldest and most staid citizens.

What is the Big Bang?

In the view of modern cosmologists, the Big Bang is the event that marked the birth of our universe.

What’s a constellation? What’s an asterism?

Both constellations and asterisms are patterns of stars. What's the difference?

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