A multitude of bright spots, behind which it becomes difficult to see the absolute darkness of the Universe. A series of images that herald a promising future. Last Thursday, NASA released the first images recorded by the instruments of the James Webb Telescope (JWST), which is in orbit about 1.5 million kilometers from Earth.
Leaving on December 25 with an Ariane 5 rocket, the space observatory has since encountered no problems in the program that will lead it to make its first scientific observations this summer. After completing its development and reaching its final destination in January, it successfully aligned all 18 sections of its primary mirror in March, giving its first image of the 2MASS J17554042 + 6551277 star, located 2,000 light-years from our planet. .
All that remained was to calibrate his four instruments, all operating in the infrared. This meant that they were given time to reach their operating temperature – which for one of them, the MIRIM imaging system, is around -266 ° C. A milestone was reached on April 21, according to NASA, allowing the mission’s engineers and scientists to direct JWST into the Large Magellanic Cloud, a dwarf satellite galaxy in our Galaxy.
“Science will take a huge step forward”
So the instruments were able to immortalize and restore the series of images unveiled last week by the US space agency, which show hundreds of thousands of stars. “After a thorough review, it was confirmed that the telescope was able to capture sharp and well-focused images,” he wrote in a statement, adding that the telescope’s “optical performance” “exceeded expectations”. more optimistic engineers.
“It simply came to my notice then. […] “It was immediately great and we could see the image quality we were looking for,” Pierre-Olivier Lagage, an astrophysicist at the Commissariat for Atomic Energy (CEA) who worked on the development of the MIRIM illustrator, tweeted. “I’m sure we will now see things we have never seen before, amazing,” he continued. Science will make a huge leap forward. »
“These remarkable images show what can be achieved when there is a bold scientific vision for exploring the universe,” said Lee Feinberg, James Webb, head of optics, according to a NASA statement.
Two more months of patience
There is one last step before JWST actually enters active service. During this, engineers will test all observation modes allowed by the instruments to measure their performance and proper calibration.
They will also perform thermal stability tests, which consist of measuring the variation of the optical quality and the indication of the infrared systems depending on the position of the telescope and the angle at which the solar radiation hits its thermal shield. This phase “will last about two months, before the start of work during the summer,” explains NASA.
The $ 10 billion telescope will therefore be able to accomplish its mission: to capture the light signals emitted by the first galaxies to form after the Big Bang 13.5 billion years ago. and may give us answers about the birth of the Universe.