Put a ring on it! 💍

Compare views of the Southern Ring nebula and its pair of stars by Webb’s NIRCam (L) & MIRI (R) instruments. The dimmer, dying star is expelling gas and dust that Webb sees through in unprecedented detail: nasa.gov/webbfirstimage… #UnfoldTheUniverse The image is split down the middle, showing two views of the
The stars – and their layers of light – steal more attention in the NIRCam image, while in the MIRI image, Webb reveals for the first time that the dying star is cloaked in dust. In thousands of years, these delicate, gaseous layers will dissipate into surrounding space.
The Southern Ring nebula is a planetary nebula. (Despite “planet” in the name, these aren’t planets — they're shells of dust and gas shed by dying Sun-like stars.) The new details from Webb will transform our understanding of how stars evolve and influence their environments.
Bonus: Check out the Southern Ring Nebula as captured by @NASAHubble in 1998! This Hubble image clearly shows two stars near the center of

• • •

Missing some Tweet in this thread? You can try to force a refresh
 

Keep Current with NASA Webb Telescope

NASA Webb Telescope Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @NASAWebb

Jul 11
👀 Sneak a peek at the deepest & sharpest infrared image of the early universe ever taken — all in a day’s work for the Webb telescope. (Literally, capturing it took less than a day!) This is Webb’s first image released as we begin to #UnfoldTheUniverse: nasa.gov/webbfirstimage… The background of space is black. Thousands of galaxies appe
This isn’t the farthest back we’ve observed. Non-infrared missions like COBE & WMAP saw the universe closer to the Big Bang (~380,000 years after), when there was only microwave background radiation, but no stars or galaxies. Webb sees a few 100 million years after the Big Bang. This detailed, oval map of the infant universe was created f
If you held a grain of sand up to the sky at arm’s length, that tiny speck is the size of Webb’s view in this image. Imagine — galaxies galore within a grain, including light from galaxies that traveled billions of years to us!
Read 7 tweets
Apr 28
“It’s full of stars!” ✨

This mosaic represents a sparkling turning point as we #UnfoldTheUniverse. #NASAWebb’s mirrors are now fully aligned! Next is instrument calibration, the final phase before Webb is ready for science: go.nasa.gov/3OJWBD1

What do we see here? ⤵️ Each box shows a view from ...
First, a quick breakdown. “Fully aligned” means that Webb’s mirrors are now directing fully focused light collected from space down into each instrument. Each instrument is also successfully capturing images with the light being delivered to them.
In this mosaic, each engineering image is a demonstration that one of Webb’s instruments is fully aligned with the telescope and in focus. In view is a part of the Large Magellanic Cloud, a small, irregular satellite galaxy of the Milky Way. Each box shows a view from ...
Read 11 tweets
Apr 13
Cool news! Webb’s MIRI instrument recently passed through its critical “pinch point” and cooled to just a few kelvins above absolute zero, which is the coldest you can go: go.nasa.gov/3M6MbeJ

Wondering why MIRI is extremely chill? Thread ❄️ This image shows the cryocooler for the Webb telescope's Mid
All of Webb’s instruments detect infrared light (which we feel as heat), so they need to be cold to seek out faint heat signatures in the universe. MIRI detects longer infrared wavelengths than the others, so it needs to be even colder.
Webb also needs to be cold to suppress something called dark current, an electric current created by the vibration of atoms in its instrument detectors. Dark current can give the false impression that there is light from a cosmic object when there isn’t.
Read 9 tweets
Mar 30
To chill to its operating temperature of less than 7 K (-447 F or -266 C), Webb’s MIRI instrument uses a special refrigerator. But it also requires heaters to control its cooldown & prevent ice from forming in space. 🧊

Wait, ice? Allow us to explain (thread ⤵️) Contamination control engin...
When Webb launched, moist air was entrapped between components like the sunshield membranes and its many layers of insulation. Other Webb materials absorbed water vapor from Earth’s atmosphere. Most of this air escaped just 200 seconds after liftoff, but some moisture remained.
Water behaves differently in space than on the ground. In a perfect vacuum, water can exist only as a gas, but even space isn’t a perfect vacuum. Instead, water tends to "outgas" at temperatures above 160 K (-172 F or -113 C), and it tends not to below 140 K (-208 F or -133 C).
Read 7 tweets
Mar 16
Small adjustments, major progress!

Having completed 2 more mirror alignment steps, #NASAWebb’s optical performance will be able to meet or exceed its science goals. Now that’s good optics! 😉 go.nasa.gov/3KMV1gW #UnfoldTheUniverse

Curious about this image? Thread ⬇️ An engineering image from Webb which shows a bright star in
While the purpose of Webb’s latest image was to focus on a bright star and evaluate the alignment progress, Webb’s optics are so sensitive that galaxies and other stars can be seen in the background. Watch this video for an in-depth explanation of how the image was created!
Fan of a photo filter? @NASAHubble & Webb actually record light in black and white. They use filters that allow only a specific color of light through. The filtered images are then individually colored by scientists and image processors, then combined: go.nasa.gov/3u5oj3J
Read 5 tweets
Feb 11
Bonus image! When it’s time to focus, sometimes you need to take a good look at yourself.

This “selfie” taken by Webb of its primary mirror was not captured by an externally mounted engineering camera, but with a special lens within its NIRCam instrument. #UnfoldTheUniverse A black and white image of the primary mirror of the Webb Te
This special lens is meant for engineering, not science, and allows NIRCam to capture an “inward-looking” image of the primary mirror. This image helps us to check that the telescope is aligned with the science instruments. blogs.nasa.gov/webb/2022/02/1…
What you are seeing is the actual primary mirror of Webb as it observes its engineering target, a bright star. All the mirror segments are seeing starlight, but the bright segment is bright because, from NIRCam’s view, the segment is directly aligned with the star.
Read 4 tweets

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us on Twitter!

:(