At present, the oldest observations of stars and galaxies are from shortly after the start of reionization, with galaxies such as GN-z11 (Hubble Space Telescope, 2016) at about z≈11.1 (about 400 million years cosmic time). Hubble's successor, the James Webb Space Telescope, launched December 2021, is designed to detect objects up to 100 times fainter than Hubble, and much earlier in the history of the universe, back to redshift z≈20 (about 180 million years cosmic time). This is believed to be earlier than the first galaxies, and around the era of the first stars.