Here’s the most distant object known in our universe as of this moment. Its official name is UDFj-39546284, but astronomers refer to it as the “redshift 10 galaxy candidate.” How far away is it? Its estimated distance is 13.2 billion light-years away, meaning its light was emitted just 480 million years after the Big Bang. It’s roughly 150 million light-years more distant than the previous record holder.
The light of this galaxy appears blue because the galaxy was emitting very blue light due to a high rate of star birth in the early universe. By the time the galaxy’s light reached the Hubble Space Telescope, it had been stretched into the infrared due to the expansion of space. If you keep track of such things, this galaxy’s redshift value is about 10.
Credit for images on this page: NASA, ESA, Garth Illingworth (University of California, Santa Cruz) and Rychard Bouwens (University of California, Santa Cruz and Leiden University) and the HUDF09 Team.
Here’s another image of the same patch of sky as above. Of course, this patch of sky is very small in real terms – about one-tenth the diameter of a full moon. This is the deepest image of the sky ever taken in the near-infrared. Same distance as in the image above: 13.2 billion light-years. And, since light travels at a finite speed (186,000 miles per second), we see the objects in this image not as they exist now – but as they looked when the universe was 3% of its present age.
In other words, we are looking back through 96.5 percent of all time to see early, very young galaxies in this image.
Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. "Being an EarthSky editor is like hosting a big global party for cool nature-lovers," she says.