Posts by 

Andy Briggs

Exoplanets are worlds orbiting other stars

Exoplanets are worlds orbiting distant stars. Learn the history of our knowledge of exoplanets, the various types, how astronomers find them, and more.

What is a variable star?

What is a variable star? It's a star that brightens and dim in a cycle that might last hours, or weeks, or months, or longer. Astronomers know millions!

What is a globular cluster?

A globular cluster is a spherical collections of stars, orbiting in the halo of spiral galaxies. Our Milky Way galaxy has over 150 globular clusters.
Space

Milky Way’s black hole seen at last!

Astronomers have succeeded in capturing the 1st direct image of our Milky Way's black hole, a monster with the mass of 4 million suns!

Supermassive black hole a feature of most galaxies

A large galaxy typically has a supermassive black hole at its heart. These black holes contains millions - to billions - of times our sun's mass.

What are black holes?

Black holes are regions of space with gravitational fields so strong that nothing, not even light, can escape. Their sizes vary from stellar to supermassive.

What is a magnetar?

A magnetar is a strange and rare neutron star, generating almost incomprehensible amounts of energy that can be detected across the universe. How?

What is a quasar?

A quasar is an extremely bright, distant object visible to radio telescopes. The source is an active galactic nucleus fueled by a supermassive black hole.

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 the Big Bang?

In the view of modern cosmologists, the Big Bang is the event that marked the birth of our universe. What was it - when was it - and what are modern theories?