File:STScI-unfolding-sequence.jpg

English: In 2021, Webb was carefully folded up and loaded onto a ship, which passed through the Panama Canal on its way to French Guiana in South America, where it reached its launch site at the European Spaceport located near Kourou. It is beneficial for launch sites to be located near the equator: The spin of the Earth can help give an additional push to the rocket.

After launch and during the first month in space, on its way to the second Langrange point (L2), Webb undergoes a complex unfolding sequence.

Steps include:

Deploying, tensioning, and separating Webb’s sunshield, a five-layer, diamond-shaped structure the size of a tennis court; extending its secondary mirror support structure; and unfolding its primary mirror, which has a honeycomb-like pattern of 18 hexagonal, gold-coated mirror segments.

Deployment and commissioning take time—at least six months. Engineers and scientists carefully activate and confirm each and every instrument works properly before the first—but still unfocused—image of a star field is delivered about two months after launch.

In the fourth month after launch, Webb completes its first orbit around L2—and takes the first focused image. This shows that the mirrors are aligned.

After the six-month mark, Webb begins its science mission and starts to conduct routine science operations.

Credits:

IMAGE: NASA, ESA, CSA, Joyce Kang (STScI)