The Hubble Space Telescope has detected light from a small galaxy emitted about 500 million years after the big bang, an early era of the universe about which scientists know relatively little.
Last year, astronomers used Hubble to find another galaxy at a redshift of about 10, suggesting it was formed 480 million years after the big bang. But the help from gravity's magnifying glass allowed the CLASH team to learn more detail about MACS 1149-JD, Zheng said.
The team was able to use NASA's Spitzer Space Telescope, for example, to estimate the galaxy's likely mass (less than 1% that of the Milky Way) and basic shape (very compact, compared with similar galaxies observed later in the universe's 13.7-billion-year history).