If you weren’t convinced NASA made the right decision to service the Hubble Space Telescope in 2009, the latest Hubble Ultra Deep Field may change your mind. The new image, dubbed HUDF09, made its debut Tuesday morning at the 215th meeting of the American Astronomical Society being held in Washington, D.C.
The image targeted a tiny part of the southern sky with observations through 10 filters ranging from ultraviolet through near-infrared wavelengths. It includes visible-light data grabbed by Hubble’s Advanced Camera for Surveys (ACS) in 2004 and ultraviolet observations taken with the newly installed Wide Field Camera 3 (WFC3). But the real breakthrough came from WFC3 images in the near-infrared. Because the universe is expanding, visible light from the most-distant objects shifts into the near-infrared.
Essentially, WFC3 lets Hubble see farther into space and further back in time. Garth Illingworth of the University of California, Santa Cruz, who led the team that took the infrared images, says HUDF09 records galaxies with redshifts of 8 — meaning we see them as they were a mere 600 to 700 million years after the Big Bang. Or, in other words, we see them as they appeared more than 13 billion years ago. When Illingworth spoke with the press Tuesday, he emphasized these galaxies are only about 5 percent the diameter and less than 1 percent the mass of the Milky Way.
Almost as remarkable, combining these observations with those from the infrared-sensitive Spitzer Space Telescope shows that the stars in them formed about 300 million years earlier. This pushes the stars’ births back to around 300 million years after the Big Bang.
Although the HUDF09 appears dazzling on a computer screen, you get a much better sense of the overall image when you see it big. The astronomers obliged by bringing along a banner roughly 18 feet wide and 8 feet tall. It almost made me feel like I was on the bridge of the starship Enterprise, staring at the cosmos in all its glory.
More updates from 215th AAS meeting:
(NASA/ESA/G. Illingworth, R. Bouwens/HUDF09 Team photo)