Later this year, astronomers will begin a new sky survey to look for signs of the stuff among exploding stars and ancient galaxy clusters. (newscientist.com)
These can reveal distant, ancient galaxies whose light has been stretched by the universe's expansion to more than triple its initial wavelength. (newscientist.com)
This technique has also allowed him to observe extremely ancient galaxies, charting the early evolution of the universe. (discovermagazine.com)