August 22 – Stardust

Today’s factismal: Every atom in your body was created either in the Big Bang or in the inside of a star.

Joni Mitchell didn’t say it first, but she certainly said it best: “We are stardust, we are golden”. And, as any freshman astronomy student can tell you, Mitchell was right. Every atom in the universe was created either during the Big Bang or in the interior of a star. But how?

New stars form from interstellar dust and gas (Image courtesy NASA)

New stars form from interstellar dust and gas
(Image courtesy NASA)

After the Big Bang, 73% of the matter in the Universe was hydrogen and 26% was helium (the remaining matter was a mix of other stuff, mainly lithium). As the hydrogen and helium atoms fell together to form stars, they heated up so much that they lost their electrons and formed a dense plasma that squeezed the various atomic nuclei so close together that a complex chain reaction occurs, ending with the transmutation of hydrogen into helium and the release of energy. In larger and hotter stars, the reaction can go further: the helium can be fused into carbon which fuses into neon which fuses into oxygen which fuses into silicon which fuses into iron. And there the chain stops; everything over silicon is made either when a star explodes in a supernova or when two neutron stars collide.

A "star portrait" made from Hubble images (Image courtesy and copyright Sergio Albiac)

A “star portrait” made from Hubble images
(Image courtesy and copyright Sergio Albiac)

But it all starts when hydrogen and helium fall together to make stars. Thanks to the Hubble telescope (and other telescopes), we’ve got hundreds of thousands of beautiful images of new stars being born and old stars dying. And thanks to a citizen scientist and artist, we can see what we would look like as stardust using those images. Through a process known as generative art (art that is made by combining other things), Sergio Albiac fuses Hubble images to create pictures of ordinary people. If you’d like to participate in his art experiment, then head over to his Stardust page:
http://www.sergioalbiac.com/wall/stardust.html

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s