Weeks after the microscope adjustment, NASA unveiled the first fully focused image.On Wednesday, a razor sharp engineering image of a non-scripted star in the field of distant galaxies showing The optical system is working perfectly.
The goal was to show that the web could now focus closer to the light of the stars, proving that the 10 10 billion telescope did not suffer from any of the subtle optical defects as the Hubble Space Telescope initially stopped. had gone. The galaxies in the picture were a bonus, increasing the appetite of astronomers..
“This is one of the most wonderful days of my entire career at NASA, and for many of us astronomers, one of the most important days we’ve had,” said Thomas Zarbochen, NASA’s head of science. “Today we can announce that Optics will perform as per the specifications or even better. This is an amazing achievement.”
Engineers and scientists still need to calibrate the web’s science tools and make repetitive adjustments to make sure they all have fully focused light, but astronomers now know telescopes, which The most complex and expensive science spacecraft ever built, will almost certainly be..
“I’m glad to say that the telescope’s optical performance is absolutely phenomenal, it’s working really well,” Lee Feinberg, elemental manager of the web optical telescope at Goddard Space Flight Center, told reporters.
“We said last fall that we’ll know the telescope is working properly when we have a picture of a star that looks like a star. And now we have it, and you’re looking at that picture.” Are. “
The star under discussion, known as 2MASS J17554042 + 6551277, one of the many used in the alignment process. The 21.3-foot-wide primary mirror of the web was imaged in a 2,100-second display at the end of a lengthy process to accurately align the 18 sections.
The star chosen for the image was “a very ordinary, anonymous star in the sky that gave us the kind of sensory measurement we need,” said Marshall Perrin, a web-based telescope scientist at the Space Telescope Science Institute in Baltimore. Well done for. “
“It’s almost 100 times more faint than the human eye,” he said, adding that “binoculars make the viewer feel very sensitive.”
The “rays” emitted by the star are due to the hexagonal shape of the primary mirror sections of the web and the so-called diffraction spikes, which are the result of the twisting of light around three streams, holding the telescope’s secondary mirror in place.
Such patterns are common with large telescopes and bright, relatively close stars. But they do not form around dim stars and galaxies. The web was designed to study.
In either case, the mirror parts were initially connected within about a millimeter of each other. To align them so that all 18 together act as a mirror, “they need to be lined up within a few nanometers (a billionth of a meter), these are a few hundred atoms.” The diameter is the level of accuracy we need here, “Perrin said.
Using seven actuators on the back of each mirror section – six tips to control the tilt and tilt and to push or pull the center of a section, if necessary, to slightly change its shape. For – 18 aligned star images were initially brought separately. At one point. One of Webb’s devices, the Near Infrared Camera, or NIRCam, was used to map images.
“Now that we’ve completed the fourth and fifth stages of telescope alignment, we call these stages course phasing and fine phasing,” Feinberg said. “And that’s where we made the basic mirror, the parts of all 18 mirrors, (work) a basic mirror.”
“The biggest surprise after that,” Perrin said.“How closely it resembles models and predictions from the earth.”
“This is far closer to the predictions that many of us dared to hope for,” he said. “And now we’ve got what is called the diffraction-limited alignment of the telescope. The images are concentrated together as finely as the laws of physics allow. Can get from. “
“The telescope’s performance so far has been exactly what we had hoped for,” agreed Jane Rugby, a scientist with the Web Operations Project at Goddard.
“The goal here was to build a telescope that was 100 times more powerful than anything we had before,” he said. “From the initial engineering data we’ve seen so far, we know we’re on track to meet these vital science needs.”
Scientists and engineers should now calibrate other scientific instruments on the web and make the necessary small adjustments to ensure full focusing light to each. Rugby said that based on the results so far, the end of the commissioning phase and the transfer of scientific observations is on track for the end of June-July.