New Images Offer Ideas About Evolution
With a boost from a natural “zoom lens”, NASA’s Hubble and Spitzer space telescopes have found what may be one of the youngest and brightest galaxies ever seen in the middle of the cosmic “dark ages,” just 700 million years after the beginning of our universe. An infant galaxy, named A1689 - zDI, was revealed by detailed images from Hubble’s Near Infrared Camera and Multi-Object Spectrometer.
The galaxy experienced a firestorm of star birth during the dark ages, which was shortly after the Big Bang but before the first stars reheated the cold, dark universe. Strong evidence showed that it was a young star - forming galaxy in the dark ages as provided by images from NASA’s Spitzer Space Telescope’s Infrared Array Camera. “We certainly were surprised to find such a bright young galaxy 12.8 billion years in the past,” said astronomer Garth Illingworth of the University of California and a member of the research team. “This is the most detailed look to date at an object so far back in time.”
The new images offer ideas about the formative years of galaxy birth and evolution. The distant galaxy is also an ideal target for the James Webb Space Telescope, Hubble’s successor that is scheduled for launching in 2013. Also in use will be the Atacama Large Millimeter Array to be completed in 2012 and the world’s most powerful radio telescope. Images show bright, dense clumps of hundreds of millions of massive stars in a compact region about 2,000 light-years across, which is only a fraction of the width of our Milky Way Galaxy. Images also show the galaxy’s mass is about the same as galaxies in the early universe.
Because of gravitational lensing, the brightness of a faraway object has been increased by nearly ten times. This assists in detection by Hubble and Spitzer. However, Hubble’s sharp “eye” can’t see the brightest, largest stars in the galaxy, nor can the telescope see fainter, lower-mass, or single stars. The Webb telescope will be utilized to reach deep into infrared wavelengths that can’t be reached by Hubble. It is believed that the beginning of the dark ages was about 400,000 years after the Big Bang.
It started as matter in the expanding universe with cooling and forming of clouds made up of cold hydrogen. The clouds produced a thick fog and stars and galaxies started to form. The cold, foggy hydrogen reheated and ended the dark ages about a billion years after the Big Bang. “This galaxy presumably is one of the many galaxies that helped end the dark ages” said astronomer Larry Bradley of John Hopkins University in Baltimore, MD and leader of the study.
This entry was posted on Saturday, February 16th, 2008 at 3:18 am and is filed under Public Relations, Space Agency News. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.
