Until very recently the most distant known galaxy was MACS0647-JD in Camelopardlis. It was seen through the Hubble Space Telescope as it was 420 million years after the Big Bang. But Hubble has outdone itself and this week an international team of astronomers announced their discovery of GN-z11, a galaxy which was seen as it was only 400 million years after the Big Bang.

The combination of Hubble's imaging and that of the Spitzer Space Telescope imaging reveals that GN-z11 is 25 times smaller than the Milky Way and has just one percent of our galaxy's mass in stars. However, the newborn GN-z11 was growing fast, forming stars at a rate about 20 times greater than our galaxy does today. This makes such an extremely remote galaxy bright enough for astronomers to find.