Early universe looked like “vegetable soup,” researchers say

<body leftmargin="0" bgcolor="#000060" text="#FFFFFF" link="#FFFF00" vlink="#FF9900"> <b> <p class="MsoNormal"><font face="Arial" size="5">Early universe looked like “vegetable soup,” researchers say</font></p> </b> <p class="MsoNormal"><font face="Arial" size="1">Posted March 10, 2005<br> Courtesy Nature <br> and  World Science staff<br> </font> <b> <font size="2" face="Arial"><br> What did the universe look like when in its infanthood, 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. </font></b> </p> <p class="MsoNormal"> <b><font size="2" face="Arial">The early universe was as complex as today’s, researchers have found. </font></b> </p> <p class="MsoNormal"> <b><font size="2" face="Arial"> Studying the universe at this early stage is important in understanding how the galaxies near us were assembled over time. Astronomers can see these early galaxies because their light takes so long to reach us, we see them as they were long ago.<br> <br> “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,” said Jiasheng Huang of the Harvard-Smithsonian Center for Astrophysics.</font></b> </p> <p class="MsoNormal"> <b><font size="2" face="Arial">The findings are reminiscent of other recent results that show the overall, large-scale structure of the universe was already in place early on (See <a href="http://www.world-science.net/othernews/050302_univfrm.htm" target="_top">Universe matured early</a>, March 2 World Science.) The new research adds to this picture by showing that not just the large-scale structure, but the complexity was also there.<br> <br> “It’s becoming more and more clear that the young universe was a big zoo with animals of all sorts,” said Ivo Labbé of the Observatories of the Carnegie Institution of Washington, lead author of a study announcing the findings.<br> <br> Using 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.<br> <br> The 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.<br> <br> “There’s as much variety in the early universe as we see around us today,” said Labbé. “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. <br> <br> The researchers said they were 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.<br> <br> The unpredicted existence of such “red and dead” galaxies so early in time challenges theorists who model galaxy formation.<br> <br> “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 of the Center for Astrophysics, a co-author of 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.”<br> <br> The study is to appear an upcoming issue of the scientific publication <i> Astrophysical Journal Letters</i>.</font> </p> <p><font face="Arial" size="2">* * *</font></p> </b> <p><b><font face="Arial" size="2" color="#FFFFFF">Send us a <a href="mailto:editor@world-science.net">comment</a> on this story, or <a href="mailto:?Body=http://www.world-science.net/othernews/050310_earlygalfrm.htm">send it to a friend</a></font></b> </p> </body>