The James Webb space telescope

34 posts / 0 new

Tue, 2021-12-21 11:16

Michael Moriarity

The James Webb Space Telescope has been under development since 1996. Astronomers and engineers have spent their entire careers working on it. Its budget ballooned from an original $500M to $10B, and its launch, originally planned for 2007, has been delayed many times. It is now folded up inside the nose cone on top of an Ariane rocket at the European Space Agency launch site in French Guiana. Launch is scheduled for Christmas Eve.

If it reaches its station at the L2 point, 3.9 times the distance of the moon from earth, and successfully unfolds and deploys itself, it will provide views of the earliest galaxies which formed shortly after the big bang. It will also provide evidence of life, if any, on exoplanets. It is a very big deal for astronomers, and for astronomy fans like me.

This will be a very short and sad thread if it fails. On the other hand if it succeeds I, and hopefully others, will post stories of the wonders it discovers for years to come.

Wed, 2021-12-22 09:28

Michael Moriarity

Launch delayed until Christmas Day because of weather.

Sat, 2021-12-25 09:53

Michael Moriarity

Successful launch this morning. The astronomers on the project are feeling a bit more relaxed, but there are still weeks of unfolding the instrument on its way to the L2 point, and months of testing and calibration before serious observing can begin some time next spring.

Sat, 2021-12-25 15:56

Michael Moriarity

Here is a page at the NASA web site that allows you to track the progress of Webb's deployment.

Sat, 2021-12-25 16:09

Michael Moriarity

And here's a 2 minute video that shows all the stages of deployment.

Mon, 2021-12-27 16:54

MegB

Cool. Thanks for the links Michael.

Tue, 2021-12-28 19:17

Michael Moriarity

I'm glad you find it interesting, Meg. Webb has now completed the first 4 steps of its post launch deployment. It deployed its solar array first, so that it could recharge its batteries. Then it used its small thruster to carry out the first of 3 scheduled mid course corrections. Then it deployed its high gain antenna for communicating with ground stations. Finally, it completed the second scheduled course correction. If any of these had failed, it would now be a big, very expensive piece of space junk.

The most difficult and complicated stage begins next. That will be deployment of the five layer sunshield, which will hopefully keep the telescope at the cryogenic temperature required for most sensitively detecting infrared radiation from far away. This phase will play out over the next 6 days.

Fri, 2021-12-31 14:53

Michael Moriarity

The forward and aft sunshield pallets have been deployed, and the protective covers over the sunshield membranes have been rolled back. Over the next 2 days the left, then the right wings of the sunshield will be extended on their booms, and each of the 5 layers will be individually stretched to optimal tension. After that, the actual telescope deployment will begin.

Sat, 2022-01-01 10:27

Michael Moriarity

The left and right wings of the sunshield have now been deployed. According to the official NASA Webb blog:

Patrick Lynch wrote:

The completion of the sunshield cover and mid-boom deployments over the past two days marks a critical milestone for Webb: all 107 membrane release devices associated with the sunshield deployment — every single one of which had to work in order for the sunshield to deploy — have now successfully released. Webb has 178 of these ‘non-explosive actuators’ in all; 107 were used to keep the sunshield safe and folded prior to deployment.

As the mid-booms slowly pushed out horizontally from the spacecraft, each driven by a motor, they pulled the folded membranes of the sunshield with them. This extended the sunshield to its full 47-foot width all the way across the observatory.

Sat, 2022-01-01 13:28

#10

Michael Moriarity

The status page for the Webb Telescope is now showing the temperatures for 4 locations, a and b on the sunny side of the shield, c and d on the shady side. c and d will keep dropping as the telescope cools to its operating temperature. Current temps are:

a: 57C, b: 16C, c: -88C, d: -183C

Mon, 2022-01-03 11:25

#11

Michael Moriarity

The tensioning of the 5 sunshield membranes was scheduled to begin yesterday, but the Webb team has decided to delay that procedure while they gather more data on the way the observatory is responding in space. Current temps are:

a: 58C, b: 18C, c: -116C, d: -192C

Tue, 2022-01-04 13:58

#12

Michael Moriarity

Tensioning of all 5 layers of the sunshield is now complete. Deployment of the telescope itself can now begin. Current temps are:

a: 59C, b: 19C, c: -132C, d: -194C

Wed, 2022-01-05 21:13

#13

Michael Moriarity

The secondary mirror, which sits in front of the primary mirror and reflects light back to the instruments behind the primary mirror has now been successfully deployed. Current temps are:

a: 53C, b: 12C, c: -147C, d: -197C

Sat, 2022-01-08 11:58

#14

Michael Moriarity

Yesterday, the left wing of the primary mirror was unfolded and locked in place, and this morning the right wing was as well. This completes the major deployments of the observatory. It will continue moving towards its final orbit around the L2 point 1.5M km further from the sun than the earth. Its velocity will decline gradually until the final course correction burn 29 days after launch, which will insert it into its permanent orbit.

From here on, the hexagonal components of the primary mirror will be aligned, the instruments will be calibrated, and many tests will be run for about 6 months. However, it now appears very likely that this observatory will start gathering actual data for astronomers after that testing is complete. Current temps are:

a: 55C, b: 10C, c: -172C, d: -199C

Mon, 2022-01-10 16:03

#15

Mobo2000

Thanks for the updates, very interesting. Go science!

Mon, 2022-01-17 19:19

#16

Michael Moriarity

The mirror components are in the process of being moved from their stowed positions to their deployed ones. This involves a movement of 12.5mm by each mirror over the course of about 10 days. Here is a diagram of the state of deployment as of now:

Current temps are:

a: 56C, b: 11C, c: -206C, d: -201C

Thu, 2022-01-20 14:26

#17

Michael Moriarity

The mirror segment deployment is now complete. Next, they must be precisely aligned to an accuracy of nanometers. This process is expected to take about 3 months.

Current temps are:

a: 57C, b: 11C, c: -207C, d: -201C

Mon, 2022-01-24 14:19

#18

Michael Moriarity

The observatory has now been inserted into its orbit around the L2 point. Alignment of the mirrors and calibration of the instruments will continue for a few months, then the actual astronomy will begin.

Current temps are:

a: 54C, b: 13C, c: -211C, d: -202C

Sat, 2022-02-12 11:21

#19

Michael Moriarity

The first images from the Webb telescope have now been released. They aren't actual observations, but rather part of the alignment and calibration process. Here is a 3 min video from the Webb team that explains what is happening.

Current temps are:

a: 41C, b: 11C, c: -224C, d: -223C

Sat, 2022-03-19 11:41

#20

Michael Moriarity

The first test image of a star and the surrounding galaxies has been taken after completing the fine phasing stage of alignment.

Current temps are:

a: 54C, b: 14C, c: -230C, d: -234C

Sat, 2022-04-30 14:26

#21

Michael Moriarity

The previous post marked the completion of mirror alignment for one of the five major instruments on the observatory. Since then, most of the news has been about the controversy over the name of the observatory. However, today a new milestone was reached. The mirrors are now aligned optimally for all five instruments. Sample images were released from each of the five instruments. They show a portion of the nearby dwarf galaxy known as the Large Magellanic Cloud.

Current temps are:

a: 51C, b: 14C, c: -231C, d: -236C

Mon, 2022-07-11 20:11

#22

Michael Moriarity

Despite one of its primary mirrors being struck by a fairly large micro-meteorite a few weeks ago, NASA has released the first "deep field" image of distant galaxies. It is quite impressive:

Since it was taken in the infra-red, I think the colours have been computationally translated to the spectrum of visible light.

NASA wrote:
This first image from NASA’s James Webb Space Telescope is the deepest and sharpest infrared image of the distant universe to date. Known as Webb’s First Deep Field, this image of galaxy cluster SMACS 0723 is overflowing with detail. Thousands of galaxies – including the faintest objects ever observed in the infrared – have appeared in Webb’s view for the first time. This slice of the vast universe covers a patch of sky approximately the size of a grain of sand held at arm’s length by someone on the ground.

Sat, 2022-07-16 15:38

#23

epaulo13

..a 1 min video. the rest is behind a pay wall.

Link

Sat, 2022-07-16 15:58

#24

Webgear

All the images are amazing and breath taking.

Sun, 2022-07-17 10:58

#25

Michael Moriarity

There's no gorgeous image for this observation, but it is indeed mind-blowing. This is a spectrograph showing the absorption lines of the atmosphere of an exoplanet 1,150 light years away. That is, this chart shows the composition of the atmosphere of that distant planet as it was around 900CE, showing that there is water vapour there.

Mon, 2022-08-01 14:12

#26

epaulo13

James Webb Telescope has captured an unbelievable image of its FIRST supernova

Mon, 2022-08-01 21:24

(Reply to #26) #27

Live Learn Repeat

epaulo13 wrote:

James Webb Telescope has captured an unbelievable image of its FIRST supernova

Frustratingly though, sci-nature.com chooses to use an image from Hubble above the headline—most likely because the James Webb image isn’t as “unbelievable” unless you’re looking for science not pretty pictures.

Sat, 2022-09-17 12:08

#28

Michael Moriarity

About a month ago, I began seeing reports of significant differences between the first few observations of extremely distant galaxies and the current astrophysical theory of how it all started, often called the Big Bang. According to these early reports, astronomers were finding galaxies of a size and age that are inconsistent with the Big Bang as currently understood.

Unfortunately, most of these reports came from publications which also claim that aliens helped the ancient Egyptians build their pyramids. However, now Scientific American has come out with an article about the issue. The current theory of the origin of the universe is definitely being put into question, but as usual more observations are necessary to determine just what is going on. This is exactly the sort of exciting data that JWST was designed to obtain, and I eagerly await more of it.

Sun, 2022-09-18 01:18

#29

NorthReport

Thanks MM
We know so much and yet we know so little.

The James Webb space telescope is a fascinating additional tool to help us learn more about before and maybe after as well.

Sun, 2022-09-18 11:52

#30

kropotkin1951

Let me know if they get any glimpses of the Dark Forest.

Sun, 2022-10-16 19:36

#31

NorthReport

James Webb telescope pictures didn’t begin as stunning images. Here’s how they started out — and how researchers brought them to life

They walked “the bridge between science and art” to account for imperfections in cameras and use other methods to represent what telescope captured.

https://www.thestar.com/news/canada/2022/10/16/james-webb-telescope-pict...

Tue, 2022-11-01 14:28

#32

epaulo13

..scroll down on the linked page for this story.

NASA's Webb Space Telescope Reveals Sparkling Scene Invisible to Hubble

Some 270 million light-years from Earth, two galaxies are on a collision course. And this event has led to a swath of stars being born. ESA/Webb, NASA, CSA, L. Armus, A. Evans

Sun, 2022-12-25 17:42

#33

Michael Moriarity

Anton Petrov is one of the few YouTube science commentators I follow. Here is his summary of the recent findings by the JWST. Good explanations and lots of pretty images too. 15min.

Wed, 2023-07-12 13:25

#34

Michael Moriarity

NASA has released a wonderful image for the first anniversary of JWST. It shows a region of the galaxy a mere 390 light years from here. Known as the Rho Ophiuchi cloud complex, it is the closest star-forming region to Earth. New stars are forming from sections of this large cloud of gas and dust, in much the way our own sun probably formed about 4.5 billion years ago. Ars Technica has a nice article about it.