In 2004 the Supernova Cosmology Project based at Lawrence Berkeley National Laboratory used the Hubble Space Telescope to find a tantalizing supernova that appeared to be almost 10 billion light-years distant. But researchers had to wait years until a new camera was installed on the Hubble before they could confirm the spectrum and light curve of supernova SCP-0401—the supernova furthest back in time useful for precise measures of the expansion history of the universe.
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