The final unfolding of the huge primary mirror of the agency's James Webb space telescope was completed yesterday. The two week deployment phase began with the launch of the observatory on Christmas Day.
The largest, most powerful space telescope ever built had to be folded up tightly so it could fit inside the Ariane 5 launch rocket.
Engineers have been directing the observatory piece by piece as it heads on its journey to a stable point a million miles from the Earth. The sun shield and secondary mirror have already been deployed.
Last week, Nasa began the final stages of deployment of the main mirror, which will collect light from the furthest depths of the universe and which is made up of 18 gold-coated segments. The first panel was successfully deployed on Friday, a process that took five and a half hours.
The telescope was launched from French Guiana.
The second segment of mirrors was released yesterday, which completed the telescope's large mirror. The last segment was held in place by engineers last night.
Thaller said that she felt a glow in her chest after seeing the mirror deployed. The staff from the mission team shared high-fives in the control room.
Described as a "time machine" by scientists, the James Webb telescope will allow them to study the beginning of the universe shortly after the big bang, and to hunt for signs of life-supporting planets in our own galaxy.
After traveling 400,000 miles to its destination, the James Webb will need five more months to calibrate its instruments.
The prospect of capturing images of the first galaxies to form after the big bang, understanding how stars are born and evolve, and investigating the potential for life to appear in planetary systems is offered by the James Webb. It will take a decade to do all this, its maximum likely lifetime. The telescope will run out of fuel and drift off course after 10 years.