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The Neil Gehrels Swift Observatory

Historical Record of Maximum Redshifts Observed

Historical Record of Maximum Redshifts Observed

The historical record of redshift detections. The redshift of the most distant object detected in 3 categories is shown as a function of year. It is seen that gamma-ray bursts have only been found at high redshift in recent years, but are quickly becoming among the most distant objects known in the universe. Courtesy of N. Tanvir.