The countdown to James Webb‘s first-star observation has begun. After a flawless launch, the $10 billion space telescope moves into its operational orbit.
From Earth, however, we will be unable to see its initial ascent into orbit since the observatory does not contain monitoring cameras, popularly known as “selfie cameras”.
In response to questions from the community, NASA has posted a thread on the James Webb Space Telescope Twitter profile explaining the reasons why, despite having considered a monitoring camera system to observe the satellite’s deployment stages, they finally decided to scrap the idea in favor of using thermal, mechanical and electrical sensors.
We've been hearing you loud and clear: Why doesn't Webb have cameras for its journey to #UnfoldTheUniverse? It sounds like a no-brainer, but there's more to it than meets the lens. Thread ⬇️ pic.twitter.com/CrurG7OZgW— NASA Webb Telescope (@NASAWebb) January 6, 2022
Installing a camera, a risky decision
However, even if cameras had been installed onboard the James Webb during its initial minutes in orbit, on its journey to the Lagrange point 1.5 million kilometers from Earth, the risks outweighed the benefits of doing so. Light is the first issue NASA highlighted on Twitter.
Cameras on the telescope’s side facing the Sun will have glare and contrast issues because of the gold mirrors’ reflection of light, says the US space agency. However, on the other side of the satellite, there will be total darkness in front of a camera lens.
NASA also lists wiring as an issue. In order to avoid heat transfer and vibration, the cables would have to pass through the telescope’s moving components. Remember that, unlike the Hubble, the James Webb cannot be repaired if it malfunctions due to its remote location.
It’s also a tremendous task to figure out where to put the cameras and how to regulate the temperature. Because the telescope’s dark side is so cold, NASA would have needed a camera with cryogenic capabilities to function.
“Plastics fall apart, shrink, and crack, and glues don’t hold together,” says the agency.
Before dismissing this possibility, the engineers analyzed and tested a camera system (remember, the James Webb took nearly three decades to create). They determined, however, that these methods would not give useful monitoring and diagnostic data for people operating the telescope from Earth.
If you are one of the people who have been following the telescope’s progress to its orbit, you now know why there are no images of, for example, the deployment of its solar shield and why Mission Control sees animations and data from telemetry on the screen.
As for the telescope’s observation capabilities, they promise to surprise. As NASA explains, the James Webb has four infrared instruments that will allow us to see beyond the stars and explore the primitive structures of the universe to better understand their origin and our place in it.
Image Credit: NASA Webb
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