Image of the Day: Violent Glowing Blob 100-Billion-Miles Wide Cloaks Massive Star
News Update: New Research Says 2010 NASA Finding of Arsenic-Based DNA Inconclusive

Dwarf Galaxies --"The Cosmic Equivalent of Viewing Ancient Greece Live, Today"

 

           Dwarfgas

 

Dwarf galaxies are the equivalent of historical villages. They still have most of their ‘old buildings’ intact, so we know what they were like when they were first built." according to David Nicholls. who led new research conducted at Australian National University. "On the other hand, in huge cities like Beijing, nearly all the old buildings have been ripped up and you can’t tell what they were like originally – just like larger galaxies."

Nicholls, from the Research School of Astronomy and Astrophysics, part of the ANU College of Physical and Mathematical Sciences, used the ANU 2.3 metre telescope at the Siding Spring Observatory to study distant dwarf galaxies. The galaxies are regarded as ideal ‘laboratories’ for finding out how the Universe has evolved since the Big Bang.

“At the beginning of the Universe, the only elements around were hydrogen and helium. Big stars formed from these elements and, as they evolved, burned the hydrogen and helium into an ‘ash’ of heavier elements. This ash included nitrogen, carbon and oxygen, which are essential for life,” Nicholls said.

“When these big stars ran out of fuel, they blew up in the form of supernovae and mixed the heavier elements back into the hydrogen clouds. New stars grew from the enriched gas. But in Dwarf galaxies, this process has happened very slowly,” he said.

“By studying dwarf galaxies, we can see what the Universe was like long ago. To do this, we measure the light from the various elements mixed into the hydrogen clouds in the dwarf galaxies, which tells us how enriched they are and how they have evolved since the Universe began.” It's the comsic archeological equivalent of viewing ancient Greece live, today.

But when he started to analyze his measurements, Nicholls discovered that the data didn’t fit the conventional theories. He set out to solve the mystery, and made an unexpected discovery.

“I found that the energies of the electrons in the gas clouds were not distributed the way people had always thought they should be. I used similar measurements of electron energies made by space probes in our Solar System as the basis for a new theory about how gases behave in distant galaxies. To my surprise, it explained my data and also solved other problems that had remained unexplained for over 40 years.”

Nicholls said his research will allow more accurate measurements of the elements in distant galaxies and help to explain the evolution of the Universe.

The research is published in The Astrophysical Journal and is available online.

The Radio/Optical Image at top of page is of dwarf galaxy UGC 5288. The bright white center object is visible-light; purple is giant hydrogen-gas disk. Using the National Science Foundation's Very Large Array (VLA) radio telescope, astronomers found that this small galaxy 16 million light-years from Earth is surrounded by a huge disk of hydrogen gas that has not been involved in the galaxy's star-formation processes and may be primordial material left over from the galaxy's formation.  

The Daily Galaxy via Australian National University

Image credit: Van Zee, NOAO, NRAO/AUI/NSF

Comments

I wish Richard Chanfray (Who lives forever and knows everything) visit EARTH again and helped with some things like WEATHER, PEACE.

Whoops! You have linked to the wrong David Nicholls. It's an easy mistake. David Nicholls is a very common name. :-) Here's a link to the correct one. http://www.mso.anu.edu.au/~nichod/

Verify your Comment

Previewing your Comment

This is only a preview. Your comment has not yet been posted.

Working...
Your comment could not be posted. Error type:
Your comment has been posted. Post another comment

The letters and numbers you entered did not match the image. Please try again.

As a final step before posting your comment, enter the letters and numbers you see in the image below. This prevents automated programs from posting comments.

Having trouble reading this image? View an alternate.

Working...

Post a comment

Your Information

(Name is required. Email address will not be displayed with the comment.)