The Crab Nebula is M1 and the Andromeda Galaxy is M31. Over a hundred deep-sky objects with "M" numbers are listed in the Messier Catalogue. Charles Messier, 18th-century comet hunter, is known today less for his comets and more for his catalog of things that aren't comets.

"The Chemical Cosmos: A Guided Tour" is an astronomy book about chemistry - or perhaps a chemistry book about astronomy. It's an engrossing guided tour that will take you from the baby Universe through the first stars, the formation of solar systems and to our search for the origins of life.

You've learned about the night sky with binoculars and you want to see more. What kind of telescope is good for a beginner? Here are some hints for choosing and using your first telescope. They've come a long way since Galileo first looked up through a telescope.

Christmas is a special day with a magic of its own. A Christmas eclipse is a great treat and centuries ago a long-awaited comet finally showed up on Christmas day. On the other hand, imagine spending the holidays a quarter of a million miles from home, as the crew of Apollo 8 did.

How many, and what kinds of birds are there around? How do we classify a million galaxies in sky survey images? How dark is the sky? Citizen scientists help to find out all of these things - and more. You could be a citizen scientist too.

Doesn't everyone know that in the 15th century people thought the Earth was flat? And that brave Christopher Columbus sailed westward from Spain to get to Asia to show that the Earth was round? Once I'd have answered “Yes” to both of these questions, but it turns out that they are myths.

A dazzling queen of ancient Egypt was the inspiration for the constellation Coma Berenices. It's small and dim, but contains the Galactic North Pole and multitudes of galaxies.

People once thought that comets were the messengers of major disasters. Today we know that they are visitors from the most distant regions of the Solar System. Other stars have exoplanets and they seem to have exocomets too.

Ill omens, objects of fascination, bringers of life, key to the ancient history of the Solar System. Comets are all of these things. Find out more about these small Solar System bodies.

Constellations and asterisms are both patterns of stars. So what is a constellation? And If Saturn is in the constellation Virgo, has it left the Solar System? Why is the Big Dipper an asterism and not a constellation?