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Posts by
Editors of EarthSky
Black hole, compact, dense, how do they form?
Cygnus X-1, an x-ray source, was one of the first black hole candidates to be discovered. It is thought to contain a black hole orbited by a bright, young star.
September 15, 2009
Can I see our galaxy from Earth?
On a very dark clear night - and if you look in the right direction - you can see a bright region of our own Milky Way galaxy.
September 15, 2009
How can some fish change from female to male?
Parrotfish an anemonefish can live for a while as male fish or female - but different hormones kick in and cause it to change.
September 15, 2009
Is red Antares bigger than our sun?
The ancients saw red Antares as the ruby Heart of the Scorpion in the constellation Scorpius. This star has since ballooned in size.
September 15, 2009
Jean Bahr on arsenic in drinking water
Jean Bahr suggests that water drawn from private wells be tested for arsenic and other potential toxic substances, even in the U.S.
September 14, 2009
John Goff describes how Hurricane Ike eroded Gulf Coast islands
John Goff said the most erosion from hurricane Ike occurred when the hurricane subsided, as water rushed out of an overflowing Galveston Bay, back into the Gulf of Mexico.
September 14, 2009
Could you drive fast enough to keep a sunset in view?
Is it possible to see an endless sunset? The answer depends on the speed of Earth's rotation and your precise location on the globe.
September 13, 2009
What causes the hiccups?
You might get hiccups if you laugh too hard, or eat spicy food, or if your stomach becomes bloated. And everyone has a favorite hiccup remedy.
September 9, 2009
Stars, how big can they get?
The theoretical size limit for the biggest stars keeps going up! We know of stars between between 60 and 100 times as massive as our sun.
September 9, 2009
Reflective crops may curb global warming
How leaves are arranged in the canopy can make a big difference as to how much sunlight is reflected back from the reflective crops.
September 7, 2009
