The Helix Nebula, also known
as NGC 7293, is a large planetary nebula (PN) located in the constellation
Aquarius.
Planetary nebulae are actually the remains of stars that once looked a lot like
our sun. These stars spend most of their lives turning hydrogen into helium in
massive runaway nuclear fusion reactions in their cores. In fact, this process
of fusion provides all the light and heat that we get from our sun. Our sun
will blossom into a planetary nebula when it dies in about five billion
years.
When the hydrogen fuel for the fusion reaction runs out, the star turns to helium for a fuel source, burning it into an even heavier mix of carbon, nitrogen and oxygen. Eventually, the helium will also be exhausted, and the star dies, puffing off its outer gaseous layers and leaving behind the tiny, hot, dense core, called a white dwarf. The white dwarf is about the size of Earth, but has a mass very close to that of the original star; in fact, a teaspoon of a white dwarf would weigh as much as a few elephants!
Explanation via NASA
Images used via ESO
http://www.eso.org/public/images/eso1205d/
When the hydrogen fuel for the fusion reaction runs out, the star turns to helium for a fuel source, burning it into an even heavier mix of carbon, nitrogen and oxygen. Eventually, the helium will also be exhausted, and the star dies, puffing off its outer gaseous layers and leaving behind the tiny, hot, dense core, called a white dwarf. The white dwarf is about the size of Earth, but has a mass very close to that of the original star; in fact, a teaspoon of a white dwarf would weigh as much as a few elephants!
Explanation via NASA
Images used via ESO
http://www.eso.org/public/images/eso1205d/
No comments:
Post a Comment