The James Webb Space Telescope is the most powerful telescope ever built — a moment that has been decades in the making.
The telescope, which includes instruments from the Canadian Space Agency and the European Space Agency, has endured years of delays, including a combination of factors brought on by the pandemic and technical challenges.
Here are some of the key dates:
- 1989: The concept for Webb was first imagined as a successor to the Hubble telescope at a workshop.
- 2004: Construction began on Webb. Thousands of scientists, technicians and engineers from 14 countries have spent 40 million hours building.
- 2018: The telescope was initially planned to launch in 2018, but endured years of delays, including a combination of factors brought on later by the pandemic and technical challenges.
- December 2021: The previous launch date of Dec. 18 was pushed to Dec. 22 after technicians were preparing to attach the telescope to the upper stage of the rocket when "a sudden, unplanned release of a clamp band caused a vibration throughout the observatory," according to the agency. After testing and reviewing the observatory, teams concluded that the telescope was not damaged. After another delay, weather pushed the launch back again one more day from Dec. 24 to Dec. 25.
- Dec. 25, 2021: The telescope successfully launched from Europe's Spaceport in French Guiana.
- Dec. 26, 2021: Webb released its antenna assembly, including a high-data-rate dish antenna, that will serve as the telescope's way of sending back 28.6 gigabytes of science data twice a day. Once it is in orbit, Webb will continue to communicate with teams on Earth and the space observatory using the Deep Space Network, which is composed of three massive antenna ground stations in Australia, Spain and California.
- January 2022: Webb reached it final destination in space and unfurled its tennis court-size sunshield and unfolded a massive gold mirror. It is in an orbit called the second sun-Earth Lagrange point, or L2. This vantage point is ideal for Webb because the gravitational forces of the sun and Earth will basically ensure the spacecraft doesn't have to use much thrust to stay in orbit. And it will allow the telescope to have an unimpeded view of the universe, unlike the Hubble Space Telescope, which moves in and out of Earth's shadow every 90 minutes.
- March 2022: Webb completed a series of tests to make sure it was working as expected. The team didn't encounter any issues and determined that Webb can observe light from distant objects and feed that light into the science instruments aboard the observatory.
- May 2022: One of the 18 golden segments of the James Webb Space Telescope's giant mirror was hit by a micrometeoroid. Spacecrafts don't have a protective bubble of atmosphere around them like the Earth does, so it's almost impossible to avoid these impacts. Fortunately, each hexagonal mirror segment is fully adjustable, and the impacted segment has already been adjusted to lessen some of the distortion.