NASA today announced that astronomers have found a candidate for the new most distant galaxy ever seen. This comes just after a similar announcement in September, when a different red blob took the record.
The object, dubbed MACS0647-JD, is observed to have existed only 420 million years after the big bang. The light from the small galaxy has traveled 13.3 billion years to reach Earth.
MACS0647-JD is the latest find from the Cluster Lensing and Supernova Survey with Hubble (CLASH) group, which uses massive galaxy clusters as gravitational lenses to magnify the distant galaxies behind them. The technique magnifies the brightness of these galaxies in the Hubble telescope's images. Specifically, astronomers used the galaxy cluster MACS J0647+7015 to magnify the image of the newly discovered galaxy.
"This cluster does what no man-made telescope can do," said Marc Postman, head of the Community Missions Office at the Space Telescope Science Institute. "Without the magnification, it would require a Herculean effort to observe this galaxy."
The new galaxy is only 600 light-years wide. As a comparison, the Milky Way galaxy is 150,000 light-years wide. Due to its size, astronomers have speculated that MACS0647-JD may be the early form of a larger galaxy.
"This object may be one of many building blocks of a galaxy," said Dan Coe, and a astronomer at the Space Telescope Science Institute. "Over the next 13 billion years, it may have dozens, hundreds or even thousands of merging events with other galaxies and galaxy fragments."
Coe is also the lead author of a new study on the galaxy which will appear in a December issue of The Astrophysical Journal. Coe and other CLASH researchers spent months ruling out other explanations for the object , including red stars, brown dwarfs, and red galaxies.
NASA's Spitzer Space Telescope was used to gain images of the galaxy at longer wavelengths and help determine the object's great distance. Spitzer will be used in the future to estimate the age and dust content of the galaxy.