Stars are born, we see their light in the sky, and they die. Find out about the patterns of stars we see, about the stars themselves and the galaxies they inhabit.
ABC of Astronomy B Is for Bok Globule
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 a Greek letter. And B is for Bailyīs beads. You wonīt find them in a jewelry shop, but you might see them in a solar eclipse, as Francis Baily did.
ABC of Astronomy D Is for Double Star
We're used to having just one Sun, so the planet Tatooine in George Lucas's Star Wars seems exotic with its double sun. Yet at least half the stars we can see in the sky are doubles. But a "double star" can be a true binary or just an optical double, which is a chance alignment of unrelated stars.
Annie Jump Cannon
Oh! Be a fine girl (guy)--kiss me! This is the traditional mnemonic for the way stars are classified: OBAFGKM. Find out about the astronomer and suffragette who devised the system and who said that astronomical spectroscopy made it "almost as if the distant stars had acquired speech."
Cancer the Crab
Cancer the crab scuttles across the late winter sky, well away from its nemesis Hercules. Cancer is a zodiac constellation, the Tropic of Cancer is named for it, and it has existed for over three thousand years. Yet it seems to be a dim and unremarkable constellation. Why all the attention?
Did you know there are 88 official constellations? Learn what they are and how to find them. On cloudy nights you can read the ancient myths and legends that tell their exciting stories.
Cosmic Ghosts, Ghouls and Vampires
Astronomers use colorful language for cosmic objects. But unlike ghosts, ghouls and vampires in horror stories, the cosmic ones arenīt scary late at night. Here are tales of the birth, evolution and death of stars, a blinking demon and a star that, at Halloween, seems like the Sunīs ghost.
Do Red Dwarfs Live Forever
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.
Epsilon Eridani - A Norse God in the River
Eridanus is the great river that flows through the southern sky. One its stars, Epsilon Eridani, is of special interest to us because of its nearness and because the sunlike star has a planetary system. As a result of a new IAU naming policy, the star and its planet are now also Ran and AEgir.
Galactic Winter Games
Welcome to the Galactic Winter Games, a starry tribute to Earthīs Winter Olympic Games. Itīs a tour of some really cool cosmic sights as well as some hot ones, such as one of the biggest explosions in the Universe.
Gemini - the Celestial Twins
Gemini. A story of the love and loyalty of two brothers parted only by death. Includes a star thatīs actually a system of six stars, and a giant star that can help us measure distances in space. Contains an object that completely baffled astronomers for twenty years.
You can see the International Space Station from where you live. But when and from which direction? What are the two bright stars youīve seen after sunset? Whatīs an Iridium flare? The website Heavens-Above is a tool for beginners and experienced observers to answer questions like this.
How Big Are the Biggest Stars
What is the biggest star yet discovered? It's harder than you might think to answer this question. But here's a short tour of big, bigger and absolutely enormous stars - including some impossible ones.
Mizar and Alcor Horse and Rider
The Big Dipper is part of the constellation Ursa Major. It's probably the best known item in the night sky after the Moon. More people could pick out its seven stars than could locate the Seven Sisters, the Pleiades. But are there only seven stars in the Big Dipper? What about the Horse and Rider?
The International Astronomical Union is the official body in charge of naming celestial objects. But how do they name stars? Do all the stars have names? Can you buy a star name for a friend? Find out here.
Pleiades - the Seven Sisters
The Pleiades - the Seven Sisters - were shown in star catalogs six thousand years ago. Visible from northern and southern hemispheres, probably every culture that ever watched the sky had a name for them. But what is this group of stars? And are there actually seven of them?
Polaris - 10 Fascinating Facts
Today we travel paved roads using good maps or a GPS system to find the way. Imagine sailing uncharted waters or journeying through trackless deserts without such help. In the northern hemisphere one of the greatest of navigational aids has for nearly two thousand years been the north star Polaris.
Polaris Facts for Kids
Polaris, the North Star, has been a navigation star for 1500 years. Itīs easy to find using the pointer stars of the Big Dipper. Did you know that it hasnīt always been the North Star? Or that itīs really three stars?
Red Dwarfs - Ten Facts for Kids
If you go outside on a clear dark night, you might see a few thousand stars. But without a telescope, not a single one will be the most common type of star in the Universe. You wonīt see red dwarfs, the stars that will still be shining in the far distant future when all the others have died.
Smallest Star in the Universe
No one could possibly say that a star is the smallest one in the whole Universe. But the smallest known star is 2MASS J05233822-1403022, which is a pretty big name for a star that's about the size of Saturn. Could there be even smaller ones as yet unknown?
Spring Triangle a Seasonal Asterism
There are 88 official constellations covering the sky with no gaps or overlaps. There are also lots of asterisms, recognizable patterns of stars that aren't constellations. They have no official standing, but they have the advantage over many constellations of resembling what they represent.
Stars Ten Facts for Kids
Stars are nuclear reactors. If a really big one took the Sun's place, it would swallow up the Sun and everything as far away as Jupiter. Yet others aren't much bigger than Jupiter. Big stars don't live very long and die in a blaze of glory. Smaller ones live for billions of years.
Stars Ten Facts for Kids
Stars are nuclear reactors. If a really big one took the Sunīs place, it would swallow up the Sun and everything as far away as Jupiter. Yet others arenīt much bigger than Jupiter. Big stars donīt live very long and die in a blaze of glory. Smaller ones live for billions of years.
If stars aren't white, why isn't the night sky more colorful? If it's 93 million miles to the Sun, how many times farther away is the next nearest star? Will the Sun become a black hole and suck us in? Here's a short explanation of some common misconceptions about the stars.
Taurus the Bull
In Greek myth Taurus is Zeusīs guise for the seduction of Europa. Yet the bullīs red eye still glares at Orion in an enmity created long before the rise of ancient Greece. Todayīs Taurus is a constellation memorable for its two beautiful star clusters and one of the skyīs most amazing objects.
Who Let the Dogs out? Astronomy Homepage | Editor's Picks Articles | Top Ten Articles | Astronomy Site Map
Someone must have left the door open, because the skies are full of dogs. You can see the dogs of Orion and the hunting dogs of the shepherd Bootes in pursuit of the Great Bear. There is also the Running Dog Nebula and the memory of poor Laika, the first cosmonaut, who perished in space.
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