JWST will “keep up” with the Earth as it orbits the Sun, so that the Earth will always lie between JWST and the Sun, as in the Figure below. While JWST is in orbit, the Earth will be at a distance of ...JWST will “keep up” with the Earth as it orbits the Sun, so that the Earth will always lie between JWST and the Sun, as in the Figure below. While JWST is in orbit, the Earth will be at a distance of 1.494 x 10 9 m from the telescope, and the Sun will be 1.49598 x 10 11 m further away, in the same direction. The mass of the Sun is 1.9884 x 10 30 kg, the mass of the Earth is 5.945 x 10 24 kg, and the mass of JWST will be about 6500 kg.
