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James Webb Space Telescope (JWST)

  • 01 Apr 2022

The James Webb Space Telescope is an infrared observatory launched by an Ariane 5 rocket from Kourou, French Guiana, on December 25, 2021. It is the world’s most powerful ‘telescope’. On 25th January, 2022, the James Webb Space Telescope reached the point referred to as the second Lagrange point (L2) between the Earth and Sun. This point is 15,00,000 kilometres away from the Earth - more than four times as distant as the moon. The telescope is expected to work in this orbit for a decade or two, watching the birth of our universe

Delays and Interruptions

The James Webb Space Telescope was destined to fly in 2007 but much to the scientific community’s disappointment, the launch was delayed. A combination of engineering problems, political hesitancy and project management issues contributed to the delay of the much-awaited launch of the JWST.

For example, U.S. politicians threatened to pull funding for the James Webb Telescope in July 2011. Fortunately, in November 2011, the spacecraft was saved from all harm’s clutches.

Finally, astronomers rejoiced when the telescope was declared to be launched in March 2018. However, much to their frustration, the launch was once again delayed due to technical issues with the spacecraft. These issues were later rectified by the engineers.

In June 2018, an independent review board discussed and declared that the launch could be moved to March 2021, when the circumstances and the telescope were more stable.

The global coronavirus (COVID-19) pandemic in 2020 also impacted the JWST’s progress to make it to space. This led to another delay and NASA announced new launch date in July 2020. The new date for this historical launch was supposed to be October 31st, 2021.

The JWST’s team deserve to be applauded for their perseverance and determination towards the launch of this observatory. They faced difficult times and hardships but nevertheless kept pushing forward. However, the delays and interruptions kept coming.

In June 2021, the team encountered problems with the Ariane 5 launch vehicle. These issues pushed the launch date back to November or possibly early December 2021. In September 2021, NASA and ESA announced yet another delay for the launch. This delay was due to the observatory not being shipped on time. The observatory’s original location was in California and was supposed to be shipped to ESA’s launch site at Kourou in French Guiana. This prompted a new launch date given by the two agencies - December 18, 2021. However, bad weather conditions put a stop to the launch.

Finally, much to everyone’s relief and happiness, the James Webb Space Telescope launched on December 25, 2021, from ESA’s launch site at Kourou. The launch took place at 7:30 a.m. EST (1220 GMT; 9:20 a.m. local time in Kourou), on-board an Ariane 5 rocket.

Controversial Naming of the Telescope

The James Webb Space Telescope was previously known as the Next Generation Telescope. It was renamed the JWST in September 2002.

The JWST is named after former NASA chief James Webb. Webb took charge of the National Aeronautics and Space Administration from 1961 to 1968. He retired just a few months before NASA was able to put the first man on the moon.

The renaming of the telescope was not taken well by many. Online petitions were set up by critics to urge NASA to rename the telescope due to claims that James Webb was complicit in discrimination against LGBQT+ NASA employees during his tenure.

NASA refused to rename the telescope despite the complaints pouring in.

James Webb Space Telescope vs Hubble Space Telescope

The James Webb Space Telescope is often referred to as the successor to the Hubble Space Telescope.

The scientific goals of the JWST were motivated by the results from the Hubble Space Telescope. The two telescopes, however, have different capabilities.

Hubble observed the cosmos in optical and ultraviolet wavelengths with some infrared capabilities. Whereas, the JWST looks at the infrared light in detail and sheds light on some of the oldest stars and galaxies in the universe.

The JWST will orbit the sun whilst Hubble orbits the Earth. JWST will be too far away to be serviced and repaired unlike Hubble which can be accessed and fixed by space shuttle missions.

Mission Goals

NASA has clear cut mission goals for the James Webb Space Telescope. These are:

  • Search for the first galaxies or luminous objects formed after the Big Bang;
  • Determine how galaxies evolved from their formation until now;
  • Observe the formation of stars from the first stages to the formation of planetary systems;
  • Measure the physical and chemical properties of planetary systems, including our own Solar System, and investigate the potential for life in those systems.
For the latest news and mission updates, one can easily check this live updates page!

Mission Milestones

Owing to the successful and precise launch of the James Webb Telescope, NASA announced that the JWST should have enough fuel to more than double its minimum mission life expectancy, which is 10 years.

Accomplishments have been rolling in non-stop since the launch. Good things are sure to come to those who wait!

  • The Ariane 5 rocket captured an impressive HD video of the observatory flying away. The video shows Webb drifting and unfurling its solar panels. This will be the last we’ll ever see of the James Webb Space telescope as it does not have any cameras aboard.
  • December 26, 2021- The JWST deployed and tested a key antenna in a 1 hour process.
  • December 27, 2021- The observatory sailed beyond the orbit of the moon.
  • December 31, 2021- The telescope unfurled its sunshield.
  • January 3, 2022- The tensioning of the sunshield’s five layers began and was completed the next day.
  • January 5, 2022- The secondary mirror was successfully deployed and latched.
  • January 8, 2022- NASA announced the telescope had unfolded the giant primary mirror and is fully deployed.
  • January 24, 2022- The JWST reached its final destination (L2 - the second Lagrange point) which it will orbit after travelling nearly a million miles. This point is gravitationally stable.

 Jess Doshi 


Need To Know Webb/NASA. (n.d.).

FloridaJanuary 25, A. F.-P. C. C. |, January 25, 2022 UPDATED:, & Ist, 2022 10:55. (n.d.). James Webb Space Telescope reaches its final destination, parked 15,00,000 km from Earth. India Today. Retrieved January 27, 2022, from

DelhiJanuary 26, I. T. W. D. N., January 26, 2022 UPDATED:, & Ist, 2022 17:05. (n.d.). Incredible facts about the James Webb Space Telescope you absolutely need to know. India Today. Retrieved January 27, 2022, from

Romo, V. (2022, January 24). The James Webb telescope reaches its final destination in space, a million miles away. NPR.

Howell, E. (2018, July 17). NASA’s James Webb Space Telescope: Hubble’s Cosmic Successor.; Space.

James Webb Space Telescope | Definition & Facts. (n.d.). Encyclopaedia Britannica.

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