The James Webb Space Telescope — successor to the famed Hubble Space Telescope — blasted off from South America in December and reached its designated exploration point in January this year. Since then, US space agency Nasa’s Webb telescope team has fully deployed its 21-foot, gold-coated primary mirror.
The Nasa team is currently on track to conclude all aspects of “optical telescope element alignment” by early May. It will then move on to approximately two months of science instrument preparations.
According to Nasa, Webb’s first full-resolution imagery and science data will be released in the summer. Here’s a look at four recent developments around the James Webb Space Telescope, which is an international program led by Nasa with partners at the European Space Agency (ESA) and the Canadian Space Agency.
Nasa's new space telescope captured its first starlight and even took a selfie of its giant, gold mirror last month. All 18 segments of the primary mirror on the James Webb Space Telescope seem to be working properly one and a half months into the mission, according to Nasa. The telescope's first target was a bright star 258 light-years away in the constellation Ursa Major. For context: one light-year is nearly 6 trillion miles or roughly 9.7 trillion kilometers.
It’s first focused image gets photobombed – by galaxies
Earlier this month, Nasa released a test image captured by Webb of a star, which is called 2MASS J17554042+6551277. The goal was to demonstrate Webb can now bring starlight to a near-perfect focus, proving the $10 billion telescope doesn't suffer from any subtle optical defects like the aberration that initially hobbled the Hubble Space Telescope – which was launched in 1990 – according to a report from CBS News. However, the image of this faraway star was photobombed by thousands of ancient galaxies. Nasa says Webb's optics and NIRCam (or Near Infrared Camera) are so sensitive that the galaxies and stars seen in the background show up.
Gaia spots Webb at L2
On 18 February, Webb Space Telescope was photographed by the ESA’s Gaia observatory. Both spacecraft are located in orbits around the Lagrange point 2 (or L2), 1.5 million km from Earth in the direction away from the Sun. Gaia arrived at this point in 2014, and Webb in January 2022. On 18 February, the two spacecraft were 1 million km apart, with an edge-on view of Gaia towards Webb’s huge sunshield, according to a statement from ESA. Webb appears as a tiny, faint spec (see image above) of light in Gaia’s two telescopes without any details visible since very little reflected sunlight came Gaia’s way.
There’s more to come from Webb
Sometime in June, Nasa expects to make public its "early release observations," a 'greatest hits' collection of initial images used to demonstrate proper functioning of Webb's instruments during its commissioning phase, a Reuters report explains. Webb's most ambitious work – the report adds – including plans to train its mirror on objects farthest from Earth, will take a bit longer to conduct. Earlier in March, the Webb team also completed a stage of mirror alignment known as “fine phasing.” At this stage in the commissioning of Webb’s Optical Telescope Element, every optical parameter that has been checked and tested is performing at, or above, expectation. Over the coming weeks, the team will proceed through the remaining alignment steps before final science instrument preparations, a Nasa statement adds.