We now know the Webb Space telescope safely reached its destination nearly 3 weeks ago at a spot behind the Earth called the second Lagrange Point, or L2, where the gravitational equilibrium will allow the craft to maintain an orbit. E.g.
As seen in the graphic, three Lagrange points (L1, L2 and L3) lie along the line of centers connecting the two major bodies, in this case the Sun and Earth. These are called "unstable" Lagrange points, while L4 and L5 are stable points. The L1 point is currently occupied by the SOHO (Solar and Heliospheric Observatory ) satellite. In the case of the L2 point, the gravitational forces of Sun and Earth balance the centrifugal effect produced by the smaller body (Webb telescope) at the point. Note the point is located 1 million miles on the opposite side of Earth from the Sun,
Work has now commenced on commissioning and calibrating the instruments, including the roughly 21-foot mirror system built by Colorado-based Ball Aerospace to capture the light from objects. The project is a joint mission of NASA, the European Space Agency and the Canadian Space Agency.
Lockheed Martin, one
of Colorado’s largest aerospace companies, built the infrared camera — Near
Infrared Camera — which will be the primary instrument to capture images. The
camera will also be used to help align the 18 hexagons that make up the mirror
that looks like a golden honeycomb as readers can see from the graphic below:
Lockheed Martin’s
space science and instrumentation director,
In a Denver Post interview about ten days ago Nordt said the infrared camera will be turned on soon to start aligning the mirror system “and we can get to starting the core science of this groundbreaking mission.” NASA said the $10 billion space science observatory will explore: planets, moons in our own solar system, as well as distant worlds (exoplanets) around other stars and also be able to capture the first light in the universe, believed to have shone about 13.5 billion years ago. While once visible, this ancient light became stretched as it propagated further from the source and now can be seen only in the infrared spectrum. A classic case of the red shift. But before the exploring phase begins, the instruments on the Webb telescope must be commissioned and tuned. Nordt said the first images likely won’t be seen until some time in May.
A good sign is a number of key steps have already been achieved. On the journey to its destination at L2, the telescope had to successfully go through several deployments of its various parts and instruments. Already a five-layered sunshield that resembles a kite - and is about the size of a tennis court - was unfurled early in January. Check!
Next, two wings of the 18 section mirror unfolded. Check! The mirror, which sits above the sunshield, was built to be initially in a folded condition so it could fit into the rocket that launched the telescope. Another major deployment was of a much smaller secondary mirror, supported by three struts. NASA said when light hits the 18-section mirror, it will reflect off and bounce to the 2.4-foot secondary mirror, which will send the light to the onboard instruments. Check!
According to Makenzie Lystrup, vice president and general manager of Civil Space at Ball Aerospace, said:
"The mirror deployments went beautifully, like the other deployments. It all feels so much more real now that we have a complete telescope,”
So we now can look forward to some spectacular observational space work that will rival even what Hubble has succeeded in delivering. It is useful to remember here that the Webb telescope has been in the works for more than two decades during which it experienced delays and budget increases. The mission was designed to last at least five years, but NASA said the craft should have enough fuel for more than 10 years. This means we ought to be receiving some truly magnificent imagery once all instruments are commissioned and tuned.
See Also:
James Webb Space Telescope Spies its First Star - ExtremeTech
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