The largest space telescope ever built is ready to show us what it’s been looking at for the past six months. But before NASA gives the world a slideshow of the James Webb Space Telescope’s early cosmic sights, the White House will give a short preview Monday afternoon.
President Biden will unveil a “deep field” image captured by the observatory. Perhaps the Webb Telescope’s greatest promise is to look at some of the first stars to illuminate the universe after the Big Bang. While Monday’s snapshot won’t be able to achieve that, it’s a testament to the principle of engineering and a hint at what’s to come from scientific instruments that astronomers have waited decades to bring online.
When will the image be revealed and how can I view it?
The first image will be unveiled by President Biden at the White House at 5 p.m. Monday on NASA TV or the agency’s YouTube channel† The New York Times will also provide a live video feed.
What picture do NASA and Biden show?
On Friday, NASA released a list of five subjects that Webb recorded with his instruments. But Mr Biden will be showing off just one of them in the White House on Monday.
The image is named SMACS 0723. It is a patch of sky visible from Earth’s southern hemisphere and often visited by Hubble and other telescopes looking to the deep past. It includes a huge cluster of galaxies about four billion light-years from here that astronomers use as a sort of cosmic telescope. The cluster’s massive gravitational field acts like a lens, distorting and magnifying light from galaxies behind it, which would otherwise be too faint and too far away to see.
Thomas Zurbuchen, NASA’s associate administrator for space science, described this image as the deepest look yet into the past of our cosmos. Subsequent images will certainly look back even further, he added.
Marcia Rieke of the University of Arizona, who led the construction of one of the cameras on the Webb telescope that took the image, known as NIRCam, said: “This image won’t hold the “deepest” record for long, but clearly shows the power of this telescope.”
And the rest of the images?
NASA will show other photos at 10:30 a.m. Eastern Time on Tuesday in a live video stream you can watch on NASA TV or YouTube. They will be displayed at the Goddard Space Flight Center in Greenbelt, Maryland.
The photos are a sightseeing tour of the universe, painted in colors that no human eye has seen – the invisible rays of infrared or heat radiation. A small team of astronomers and scientific outreach experts selected the images to demonstrate the capabilities of the new telescope and to blow the public’s socks off. Among the cosmic images are old friends of astronomers, both amateurs and professionals, who now see them in new infrared robes.
There’s the Southern Ring Nebula, a shell of gas ejected from a dying star about 2,000 light-years from here, and the Carina Nebula, a vast swirling expanse of gas and stars, including some of the most massive and potentially explosive galaxies in the Milky Way.
Another well-known astronomical scene is Stephan’s Quintet, a dense cluster of galaxies about 290 million light-years from here in the constellation Pegasus.
The team will also release a detailed spectrum of an exoplanet known as WASP-96b, a gas giant half the mass of Jupiter that orbits a star 1150 light-years away every 3.4 days. Such a spectrum is the kind of detail that could reveal what’s in the atmosphere of that world.
Why did it take so long to share Webb’s first images?
Going to space on Christmas Day last year was just the first step for the James Webb Space Telescope.
The spacecraft has been orbiting the second Lagrange point, or L2, about a million miles from Earth since Jan. 24. At L2, the gravitational forces of the Sun and Earth keep Webb’s motion around the Sun in sync with Earth’s.
Before he got there, pieces of the telescope had to be carefully unfolded: the sunshade that keeps the instruments cold so that the weak infrared light can precisely catch it, the 18 gold-plated hexagonal pieces of the mirror.
For the astronomers, engineers and officials who watched on Earth, the deployment was an exciting time. There were 344 single-point failures, meaning that if any of the actions hadn’t worked, the telescope would have ended up as useless space junk. They all worked.
The four scientific instruments of the telescope also had to be turned on. In the months following the telescope’s arrival at L2, operators meticulously aligned the 18 mirrors. In April, the Mid-Infrared Instrument, or MIRI, which requires the coldest temperatures, was cooled to minus 447 degrees Fahrenheit, and scientists were able to begin a final set of checks. Once these and other steps were done, the science could begin.
How does the Webb compare to the Hubble telescope?
The Webb telescope’s primary mirror has a diameter of 6.5 meters, compared to Hubble’s, which is 2.4 meters, allowing Webb to collect about seven times as much light and thus see further into the past.
Another crucial difference is that Webb is equipped with cameras and other instruments that are sensitive to infrared or ‘heat’ radiation. The expansion of the universe causes the light normally in visible wavelengths to be shifted to longer infrared wavelengths normally invisible to the human eye.