Ask Ethan #34: Using up the Universe’s fuel (Synopsis)

“If the human condition were the periodic table, maybe love would be hydrogen at No. 1.” –David Mitchell

It’s the end of the week, so once again it’s time for Ask Ethan. You’ve sent in your questions and suggestions, and have I got a doozy of a question for this week about the simplest element in the Universe: hydrogen.

Image credit: WISE mission, NASA / JPL-Caltech / UCLA, via http://www.nasa.gov/mission_pages/WISE/multimedia/gallery/pia13443.html.
Image credit: WISE mission, NASA / JPL-Caltech / UCLA, via http://www.nasa.gov/mission_pages/WISE/multimedia/gallery/pia13443.html.

From the Big Bang to the present day, and far into the future, just how much of the Universe’s hydrogen has been (or will be) turned into heavier elements, and how much will remain hydrogen for all time?

Image credit: NASA, ESA and the Hubble SM4 ERO Team, via http://www.spacetelescope.org/images/heic0910e/.
Image credit: NASA, ESA and the Hubble SM4 ERO Team, via http://www.spacetelescope.org/images/heic0910e/.

Go and read the whole story here.