News tagged with stars

How small can galaxies be?

Yesterday I talked about just how small a star can be, so today let's explore just how small a galaxy can be. Our Milky Way galaxy is about 100,000 light years across, and contains about 200 billion stars. Th ...

Sep 29, 2014
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The evidence for pair-instability supernovae

A supernova is a stellar explosion. They can occur when a large star exhausts its ability to fuse hydrogen into higher elements, and its core collapses. The resulting rebound rips apart the outer layers of ...

Oct 06, 2014
4.9 / 5 (20) 5

How much of the universe is black holes?

We all fear black holes, but how many of them are there out there, really? Between the stellar mass black holes and the supermassive ones, just how much of our Universe is black holes?

Jun 17, 2014
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Image: NGC 6872 in the constellation of Pavo

This picture, taken by the NASA/ESA Hubble Space Telescope's Wide Field Planetary Camera 2 (WFPC2), shows a galaxy known as NGC 6872 in the constellation of Pavo (The Peacock). Its unusual shape is caused ...

Sep 23, 2014
4.9 / 5 (10) 1

How genes trace life on Earth

A complete tree of life – showing how and when organisms are related to each other – has long been desired by biologists, but obscured by the vagaries of the fossil record. ...

Sep 25, 2014
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