Webb is scheduled to launch in 2021.
No. The Webb and Hubble missions are expected to overlap, providing complementary science. Hubble will continue its mission as long as its instruments are functioning.
No. Unlike Hubble, Webb is not designed to be serviced. Webb will be located at a much greater distance than Hubble, beyond the Moon, instead of orbiting just above Earth. This is the reason that the minimum science mission length is five years with a 10-year goal. To insure the five-year mission, NASA has engineered Webb so that all critical subsystems are dual or will degrade gracefully with age. For instance, the Near Infrared Camera has two identical camera systems so that the optical quality can be maintained even if one fails.
Webb will also contain enough fuel for 10 years of maneuvers at its location. As with Hubble, NASA’s Chandra X-ray Observatory, and NASA’s Spitzer Space Telescope, the Webb Science and Operations Center at the Space Telescope Science Institute has the ability to change the operations of the observatory to maximize its scientific potential as it ages.
Webb will travel for about a month to reach its orbit at the second Sun-Earth Lagrange point (L2), 1.5 million kilometers (940,000 miles) from Earth.
Webb will launch from the Guiana Space Centre (Le Centre Spatial Guyanais, CSG) in Kourou, French Guiana, onboard an Ariane 5 rocket provided by the European Space Agency.
Webb needs to be kept very cool to measure the heat from objects in the universe. LEO, where Hubble resides, is too close to heat coming off the Earth and Moon, which would interfere with Webb’s precise measurements.
Webb’s deployment in space involves unfolding the sunshield and mirrors, a process that must be carefully conducted over nearly a month. The sequence is best explained visually in our deployment animation.
Webb will undergo science and calibration testing once it reaches its orbit, so regular science operations and the best images will begin to arrive around six months after launch. However, it is normal to also take a series of "first light" images that may arrive slightly earlier.
The Webb telescope is named after James E. Webb (1906–1992), NASA's second administrator. James Webb is best known for leading Apollo, a series of lunar exploration programs that landed the first humans on the Moon. However, he also initiated a vigorous space science program that was responsible for more than 75 launches during his tenure, including America's first interplanetary explorer spacecrafts. Read more about the life and impact of James Webb.