How faint can Webb see?
Webb is designed to discover and study the first stars and galaxies that formed in the early Universe. To see these faint objects, it must be able to detect things that are ten billion times as faint as the faintest stars visible without a telescope. This is 10 to 100 times fainter than Hubble can see. • What are the main science goals of Webb? Webb has four mission science goals: • Search for the first galaxies or luminous objects that formed after the Big Bang. • Determine how galaxies evolved from their formation until the present. • Observe the formation of stars from the first stages to the formation of planetary systems. • Measure the physical and chemical properties of planetary systems and investigate the potential for life in those systems. • How far will Webb look? One of the main goals of Webb is to detect some of the very first star formation in the Universe. This is thought to happen somewhere between redshift 15 and 30 (redshift explained below). At those redshifts, the U
