This week, our team turned on Webb's high-gain antenna, which helps enable a much higher data rate than the radio band Webb had been using until now, and will eventually allow Webb to send back all its images & data. #UnfoldTheUniverse
🌟 Star light, star bright…the first star Webb will see is HD 84406, a Sun-like star about 260 light years away. While it will be too bright for Webb to study once the telescope is in focus, it’s a perfect target for Webb to gather engineering data & start mirror alignment.
Look back on our successful first month after launch by reading our latest blog post, with a contribution by #NASAWebb project manager Bill Ochs: go.nasa.gov/3KVxqvh
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So…you’ve heard that the Webb telescope will be orbiting Lagrange point 2. But what even is that, anyway? And how do you orbit something that isn’t an object?
First, the basics. Lagrange points refer to locations where the gravitational forces of 2 massive objects — such as the Sun and Earth — are in equilibrium. Webb will be located more specifically at Sun-Earth Lagrange point 2, or L2 for short.
Why send Webb to orbit L2?
😎 Shade: The Sun, Earth (and Moon) are always on one side. At L2, Webb’s sunshield can always face all of these heat & light sources to protect Webb’s optics & instruments, which have to stay super cold to detect faint heat signals in the universe.
Each of Webb’s mirror segments has 3 metal pegs on its back, which fit snugly into matching sockets in the telescope structure. During launch, the mirrors were tucked safe and sound.
Tiny Dancers 🩰
Over about 10 days, each mirror segment will move out by 12.5 mm (about half an inch) to get the pegs clear from the sockets. It may not sound like much, but these initial moves are actually the largest moves Webb’s mirror motors will ever make in space!
❄️ Now that our deployments are complete, just like our telescope, we’re entering a period of cooldown. Our updates will be less frequent, but that doesn’t mean things have stopped happening: blogs.nasa.gov/webb/2022/01/1…
Thread ⬇️
First, what do we mean by “cooldown”? If you’ve been checking the temperatures of our “cold side” at webb.nasa.gov/whereiswebb, you can see we’re still a ways off from our operating temperatures of less than 50 Kelvin (about -370° F, or -223° C).
The deployment of our sunshield helped a lot with quickly lowering the temperatures on the cold side, but further cooling down will take place more slowly over time. The sunshield helps to passively cool Webb, meaning the optics get cold solely by being in the shade. 🌡
We are GO for #NASAWebb’s final mirror wing deployment this morning! Here’s what you should expect:
🔲 Fire pins to release mirror wing
🔲 Unfold mirror
🔲 Latch the wing (2+ hours) ⏱
🔲 🥳🕺🏽🎉
🔲 #UnfoldTheUniverse! (5+ months) ✨
More: go.nasa.gov/3G8Bc1P
✅ Click! We just fired the last 4 of #NASAWebb's 178 release mechanisms, or pins — all of which had to work perfectly for this unfolding to take place. These 4 will release the restraints that held Webb's mirror wing safely in place during launch. #UnfoldTheUniverse
🚗 Folks, start your engines!
As the #NASAWebb team gets ready to deploy the second primary mirror wing from @SpaceTelescope, they just completed a small motor checkout movement, ensuring the wing is ready to go. #UnfoldTheUniverse
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 ⬇️
1. Light 💡
Our gold-coated mirrors were photogenic on Earth, but the mirror side of Webb is pitch dark in space. Meanwhile, the other, Sun-facing side of Webb is so shiny that cameras there would have glare & contrast issues.
2. Power 🔌
We would have to run cables and power out to cameras on Webb, and the power balance on the cold side of Webb is especially delicate. More cables adds more of a threat of heat and vibration transfer through the wires, which could impact image quality.
Can you feel the tension? Webb is feeling it...in a good way! We tensioned 3 of 5 sunshield layers yesterday. Today we start with Layer 4: blogs.nasa.gov/webb/2022/01/0…
We just tensioned #NASAWebb’s sunshield some more, that was Layer 4. Now everybody look alive, it’s time to tension Layer 5! And better yet — keep watching along live: nasa.gov/live#UnfoldTheUniverse
If you’re tuned in to our live broadcast, now’s the perfect time to go grab a drink of water! Coverage resumes at 11:30 am ET (16:30 UTC) for the tensioning of Webb’s fifth and final sunshield layer 🤩