Young Universe Looks Like 'Vegetable Soup'

Mar 14, 2005

What did the universe look like when it was only 2 to 3 billion years old? Astronomers used to think it was a pretty simple place containing relatively small, young star-forming galaxies. Researchers now are realizing that the truth is not that simple. Even the early universe was a wildly complex place. Studying the universe at this early stage is important in understanding how the galaxies near us were assembled over time.
Jiasheng Huang (Harvard-Smithsonian Center for Astrophysics) said, "It looks like vegetable soup! We're detecting galaxies we never expected to find, having a wide range of properties we never expected to see."

"It's becoming more and more clear that the young universe was a big zoo with animals of all sorts," said Ivo Labbй (Observatories of the Carnegie Institution of Washington), lead author on the study announcing this result.

Using the Infrared Array Camera (IRAC) aboard NASA's Spitzer Space Telescope, the astronomers searched for distant, red galaxies in the Hubble Deep Field South-a region of the southern sky previously observed by the Hubble Space Telescope.

Their search was successful. The IRAC images displayed about a dozen very red galaxies lurking at distances of 10 to 12 billion light-years. Those galaxies existed when the universe was only about 1/5 of its present age of 14 billion years. Analysis showed that the galaxies exhibit a large range of properties.

"Overall, we're seeing young galaxies with lots of dust, young galaxies with no dust, old galaxies with lots of dust, and old galaxies with no dust. There's as much variety in the early universe as we see around us today," said Labbй.

The team was particularly surprised to find a curious breed of galaxy never seen before at such an early stage in the universe--old, red galaxies that had stopped forming new stars altogether. Those galaxies had rapidly formed large numbers of stars much earlier in the universe's history, raising the question of what caused them to "die" so soon.

The unpredicted existence of such "red and dead" galaxies so early in time challenges theorists who model galaxy formation.

"We're trying to understand how galaxies like the Milky Way assembled and how they got to look the way they appear today," said Giovanni Fazio (CfA), a co-author on the study. "Spitzer offers capabilities that Hubble and other instruments don't, giving us a unique way to study very distant galaxies that eventually became the galaxies we see around us now."

The study will be published in an upcoming issue of The Astrophysical Journal Letters.

This press release is being issued in conjunction with the Observatories of the Carnegie Institution of Washington.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center, Pasadena, Calif. JPL is a division of California Institute for Technology, Pasadena.

Headquartered in Cambridge, Mass., the Harvard-Smithsonian Center for Astrophysics (CfA) is a joint collaboration between the Smithsonian Astrophysical Observatory and the Harvard College Observatory. CfA scientists, organized into six research divisions, study the origin, evolution and ultimate fate of the universe.

Source: Harvard-Smithsonian Center for Astrophysics

Explore further: Short, sharp shocks let slip the stories of supernovae

Related Stories

Extremely young stellar clump in the distant universe

May 15, 2015

As part of an observing program carried out with the Subaru Telescope and the Hubble Space Telescope, a group of researchers from the Service d'Astrophysique- Laboratoire AIM of CEA-IRFU led by Anita Zanella ...

Hubble catches a stellar exodus in action

May 14, 2015

Using NASA's Hubble Space Telescope, astronomers have captured for the first time snapshots of fledgling white dwarf stars beginning their slow-paced, 40-million-year migration from the crowded center of ...

Astronomers baffled by discovery of rare quasar quartet

May 14, 2015

Using the W. M. Keck Observatory in Hawaii, a group of astronomers led by Joseph Hennawi of the Max Planck Institute for Astronomy have discovered the first quadruple quasar: four rare active black holes ...

Improved detection of radio waves from space

May 04, 2015

Geodesy is the scientific discipline that deals with the measurement of the Earth. One of the measurement techniques it employs uses radio waves from far-distant objects in space to determine factors such ...

NuSTAR captures possible 'screams' from zombie stars

Apr 30, 2015

Peering into the heart of the Milky Way galaxy, NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) has spotted a mysterious glow of high-energy X-rays that, according to scientists, could be the "howls" ...

Recommended for you

How bad can solar storms get?

2 hours ago

Our sun regularly pelts the Earth with all kinds of radiation and charged particles. How bad can these solar storms get?

Mars rover's ChemCam instrument gets sharper vision

3 hours ago

NASA's Mars Curiosity Rover's "ChemCam" instrument just got a major capability fix, as Los Alamos National Laboratory scientists uploaded a software repair for the auto-focus system on the instrument.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.