NASA will launch James Webb Space Telescope in 2021. It will observe the cosmos to uncover the history of the universe from the Big Bang and beyond.

James Webb Space Telescope will focus on four main areas: first light in the universe, assembly of galaxies in the early universe, the birth of stars and protoplanetary systems, and planets (including the origins of life).

The James Webb Space Telescope (JWST) will launch on an Ariane 5 rocket from French Guiana. Then, take 30 days to fly a million miles to its permanent home: a Lagrange point, or a gravitationally stable location in space.

It will orbit around L2, a spot in space near Earth that lies opposite from the sun. This has been a popular spot for several other space telescopes, including the Herschel Space Telescope and the Planck Space Observatory.

The powerful spacecraft will cost $8.8 billion. The Hubble Space Telescope remains in good health. So, it’s probable that the two telescopes will work together for JWST’s first years. JWST will also look at exoplanets that the Kepler Space Telescope found. Also, follow up on real-time observations from ground space telescopes.

  • First light and reionization: This has to do with the early stages of the universe after the Big Bang started the universe as we know it today. In the first stages after the Big Bang, the universe was a sea of particles (such as electrons, protons, and neutrons). The light was not visible until the universe cooled enough for these particles to begin combining.
  • Assembly of galaxies: If you want to see how the universe evolved, you should be looking at galaxies. That’s a useful way to see how matter is organized on gigantic scales. The spiral and elliptical galaxies we see today actually evolved from different shapes over billions of years. So, one of JWST’s goals is to look back at the earliest galaxies to better understand that evolution.
  • Birth of stars and protoplanetary systems: Stars form in clouds of gas and as they grow the radiation pressure they exert blows away the gas. It’s very difficult to see inside the gas. However, JWST’s infrared eyes will be able to look at sources of heat, including stars that are being born in these cocoons.
  • Planets and origins of life: Many exoplanets have been discovered in recent times. Most of them thanks to NASA’s planet-seeking Kepler Space Telescope. JWST’s powerful sensors will be able to peer at these planets in more depth, including (in some cases) imaging their atmospheres. Understanding the atmospheres and the formation conditions of planets could help scientists better predict if certain planets are habitable or not.
  • Near-Infrared Camera (NIRCam): It is provided by the University of Arizona. The telescope will detect light from stars in nearby galaxies and stars within the Milky Way. It will also search for light from stars and galaxies that formed early in the universe’s life. NIRCam will be outfitted with coronagraphs that can block a bright object’s light. Thus, making dimmer objects near those stars (like planets) visible.
  • Near-Infrared Spectrograph (NIRSpec): NIRSpec will observe 100 objects simultaneously, searching for the first galaxies that formed after the Big Bang. The European Space Agency with help from NASA’s Goddard Space Flight Center provided the NIRSpec
  • Mid-Infrared Instrument (MIRI): MIRI will produce amazing space photos of distant celestial objects, following in Hubble’s tradition of astrophotography. The spectrograph that is a part of the instrument will allow scientists to gather more physical details about distant objects in the universe. MIRI will detect distant galaxies, faint comets, forming stars and objects in the Kuiper Belt. The European Consortium with the European Space Agency and NASA’s Jet Propulsion Laboratory build MIRI.
  • Fine Guidance Sensor/Near InfraRed Imager and Slitless Spectrograph (FGS/NIRISS): This Canadian Space Agency-built instrument is more like two instruments in one. The FGS component is responsible for keeping the JWST pointed in exactly the right direction during its science investigations. NIRISS will scope out the cosmos to find signatures of the first light in the universe. It will also seek out and characterize alien planets.

The telescope will also sport a tennis-court-size sunshield and a 21.3-foot (6.5 meters) mirror — the largest mirror ever launched into space. Those components will not fit into the rocket, launching the JWST, so both will unfold once the telescope is in space.

NASA named the telescope after their former chief, James Webb. Webb took charge of the space agency from 1961 to 1968. Thus, retiring just a few months before NASA put the first man on the moon.

Webb is most closely associated with the Apollo moon program. However, he is also considered a leader in space science. Even in a time of great political turmoil, Webb set NASA’s science objectives. Thus, writing that launching a large space telescope should be a key goal of the space agency.

NASA launched more than 75 space science missions under Webb’s guidance. Including missions that studied the sun, stars, and galaxies as well as space directly above Earth’s atmosphere.