Ptolemy included 48 constellations in his 2nd century Almagest. In the 20th century, the International Astronomical Union (IAU) listed 47 of Ptolemy's constellations and added 41 newer ones. Many of them depict animals, both real and mythical.
The Solar System belongs to the Sun. More than 99% of all the matter in the Solar System is in the Sun. Everything else - planets, moons, asteroids, icy bodies, comets - is made from stuff left over from making the Sun. It's the Sun's gravity that holds everything together.
Millennia before the rise of Greece, the bull's red eye glared at Orion. But Orion doesn't feature in the Greek myth where Taurus is Zeus's guise for the seduction of Europa. Today's Taurus is a constellation memorable for two beautiful star clusters and one of the sky's most dramatic objects.
Where do comets come from? The Oort Cloud is home to a trillion comets at the edge of the Solar System, nearly half way to the next star. Sometimes they get kicked out and sometimes they come to visit the inner Solar System.
The sky is full of stars, and since prehistoric times humans have known of five nomads – planets – wandering among them. No individual discovered those planets, for they're there for all to see. So why was the sixth one – now called Uranus – not known until 1781?
Through the vision and dedication of Edward Pickering, Harvard College had one of the world's top observatories. Pickering had a secret weapon: a team of women computers. One of them was Mina Fleming who began her employment as a housekeeper and ended it as an astronomer of international repute.
B is for Bok globule, a kind of dark nebula studied by Bart Bok. B is for Bayer who invented a handy system of star designations beginning with Greek letters. And B is for Baily's beads. You won't find them in a jewelry shop, but you might see them in a solar eclipse, as Francis Baily did.
Johannes Kepler gave the first accurate description of the Solar System. As he did his work, he struggled with poverty, insecurity and bereavement in troubled times. Religion and warfare were tearing Europe apart, but Kepler never gave up his quest to understand the cosmos.
Seduction and supergiants, a beautiful blue and amber double star, vast explosions, a giant cloud that looks like North America. Where does myth end and astronomy begin? Here is a tour of some of the highlights of the constellation Cygnus the swan.