Didn't Douglas Adams write "Space is big?" Well, not only is it big, but it's also old. More than 13 billion years' worth of old. Scientists revealed today the oldest known object in space—because the galaxy UDFy-38135539 was formed a mere 600 million years after the universe.
If the astronomers on the team of the European Southern Observatory got their math right (and we would expect nothing less than perfection from the scientists of the ESO), this means the uninterestingly named UDFy-38135539 galaxy is likely the oldest known object in the universe. (Quasars, at 800 million years old, are comparative younglings.)
Because we couldn't just check its driver's license, UDFy-38135539's real age was determined through observation. The Hubble Telescope took an image of the constellation Formax, known as the Ultra Deep Field—the deepest known look at the universe. This image was captured with Hubble's super-duper camera, the Wide Field Camera 3. Later, astronomers used the Very Large Telescope in Chile to refine their measurements.
It took two months of number-crunching to determine whether UDFy-38135539 is of legal age to drink and vote. And it wasn't easy:
Studying these first galaxies is extremely difficult. By the time that their initially brilliant light gets to Earth they appear very faint and small. Furthermore, this dim light falls mostly in the infrared part of the spectrum because its wavelength has been stretched by the expansion of the Universe—an effect known as redshift. To make matters worse, at this early time, less than a billion years after the Big Bang, the Universe was not fully transparent and much of it was filled with a hydrogen fog that absorbed the fierce ultraviolet light from young galaxies.
Although UDFy-38135539 is currently the oldest known astronomical object, that title won't last. Lead researcher Matthew Lehnert, with France's Observatoire de Paris, believes that this is one of many discoveries of elderly objects waiting to be made.
"I don't think this is the limit, perhaps not even that close to it," he said.
And when it comes to observing the universe ... the sky really IS the limit.