Looking up at a clear, dark sky, you can see thousands of stars. Yet without binoculars or a telescope, the most common type of star is invisible. These are the small, cool red dwarfs that fill the sky and live practically forever.

Much of the southern sky wasn't visible to the ancient Mediterranean civilizations. Instead of representing the ancient myths, the constellations were invented long afterwards by European explorers and astronomers. Some of Abbe Lacaille's inventions are tributes to the arts.

While World War I was tearing Europe apart in 1915, a German physicist presented a theory that would shake up the way we see the Universe. The physicist was Albert Einstein, his face still unknown to the world, his name not yet a synonym for genius. How did a solar eclipse in 1919 change all that?

It can be hard to be the son of a famous man. Although his father was the first person in history to discover a planet, John Herschel had his own illustrious career. He was not only an astronomer, but also a brilliant mathematician, a talented artist, musician and poet, and a loving family man.

Aries was the winged ram from which the Golden Fleece came. Two thousand years ago his constellation marked the spring equinox when the Sun crossed the celestial equator near Beta and Gamma Arietis. The equinox is now in Pisces, but what strange object was discovered in 2007 in Aries?

In her own words, America's first woman professor of astronomy tells of her meetings with the great and good of the nineteenth century. Maria Mitchell's sister Phebe collected excerpts from journals and letters to present a potpourri of Maria's life, ideas and work.

A "celestial sleuth" solves puzzles in art, history and literature using astronomy. Why did Munch have a blood-red sky in "The Scream"? How did British sentries miss Paul Revere rowing across Boston Harbour under a full Moon? Which meteor shower did the characters in James Joyce's "Ulysses" see?

Moons of Venus and Mercury? An unknown planet nearer the Sun than Mercury? Astronomers can misinterpret what they see, too. Happily, other observers, better instruments and new theoretical understandings can put it right. Here are some phantom objects that many astronomers once thought existed.

There's a curious set of constellations in the southern skies. They don't represent exotic animals, heroic deeds or the foibles of ancient deities. They're composed of dim and nameless stars. Find out why Abbe Lacaille invented them, and take a quick tour.

Nicolas-Louis de Lacaille (1713-1762) was one of astronomy's greats. He surveyed nearly 10,000 stars in the southern hemisphere and invented fourteen new constellations still in use today. He was always thoughtful in dealing with others, but he really preferred the stars to people.