Questions tagged [james-webb-space-telescope]

NASA's James Webb Space Telescope (JWST) is an infrared space observatory that launched on Dec 25, 2021. It is the largest and most powerful space telescope to date.

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Why does the alignment evaluation image from JWST look like this?

NASA has just released a telescope alignment evaluation image from JWST for the star HD 84406 2MASS J17554042+6551277. It looks like this: Higher resolution at Wikipedia To my untrained eye, the star ...
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Why is one picture of this star blue with red, and the other red with blue?

Someone just retweeted a NASA tweet onto my timeline, and it includes two images, allegedly from the same star that was in the process of dying, taken by the new space telescope, side by side: I don'...
Tinkeringbell's user avatar
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How much larger will the "observable by us" universe be when JWST becomes operational?

Right now, using all our various current means of observing, we can "see" a sphere of X diameter around us. Webb will increase that to Y diameter. So our observable volume will increase by ...
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How many light seconds away is the JWST?

The processing for JWST's alignment is done on Earth. How long does it take for a signal from Earth to reach the JWST?
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How does JWST position itself to see and resolve an exact target?

Let's say the James Webb Space Telescope wants to move from observing the Andromeda galaxy millions of light years away to looking at the Trappist-1e planet some dozens of light years away, what ...
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What is the probability of a photon from one of these galaxies hitting the James Webb detector?

In the image of the SMACS 0723 galaxy from the James Webb space telescope can be seen distorted galaxies whose light has taken about 13 billion years to reach the telescope. On the face of it, the ...
DrMcCleod's user avatar
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Why will HD 84406 be chosen as the first target for testing JWST?

HD 84406, is a star approximately 241 light-years away in the constellation of Ursa Major. HD 84406 will be the first star to be imaged by the James Webb Space Telescope in order to test the focus of ...
NeutronCat's user avatar
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Parking a telescope at a Lagrange point: is this a good idea from a debris point of view?

The James Webb space telescope is supposed to be located at the Earth-Sun L2 Lagrange point. Do we expect the region around that point to have a higher concentration of space debris, asteroids, dust,...
FrenchKheldar's user avatar
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Has the small meteorite that hit Webb done a lot of damage?

I read on the web about Webb: A tiny meteoroid struck the newly deployed James Webb Space Telescope in May, knocking one of its gold-plated mirrors out of alignment but not changing the orbiting ...
Felicia's user avatar
13 votes
3 answers
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Has NASA released any JWST images of Trappist-1? If not, why?

According to JWST weekly schedules (found here), the Trappist-1 system was among the telescope's targets during early July. The only JWST image of an exoplanet in the Trappist-1 system that I've ...
William's user avatar
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As of now how much larger is our practically observable universe compared to just prior to JWST becoming operational

On April 2 2022 I asked for estimates of expected results. How much larger will the "observable by us" universe be when JWST becomes operational?. As of Jan 27 2024 with JWST operational for ...
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If I can't unscramble an egg, how do Astronomers unscramble views gravitationally lensed by complex mass distributions?

Quanta Magazine's Two Weeks In, the Webb Space Telescope Is Reshaping Astronomy highlights two submissions to arXiv soon after the first images were released: "Three days later, just minutes ...
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What alternative facilities would be available in the event of JWST being destroyed?

Unfortunately, space launches can and do go wrong. Suppose that after all the delays and budget overruns, the launch of the James Webb Space Telescope fails and the telescope becomes a cloud of very ...
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11 votes
3 answers
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What is the most common activity of astronomers in the JWST? [closed]

I am no astronomer. I am a computer scientist. I recently read this article: JWST has changed the speed of discovery, for better or for worse - Astronomers are working at a furious pace to analyze and ...
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Will the James Webb Space Telescope be visible from earth?

Once the JWST is in orbit around L2, would it be possible to view it using any ground based telescopes? I’m mostly thinking of equipment available to amateurs, since I don’t have a 10m reflector. But ...
user287095's user avatar
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What visual artifacts are expected from the JWST?

What visual artifacts should we expect from the images that will be released from the James Webb Space Telescope? Specifically, do we expect 3-pronged diffraction spikes (any preview how they would ...
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Will James Webb see Population III stars?

I have heard that James Webb will see the first stars that our universe produced. Can I assume that we may see galaxies that are so young that all of the stars in them are population III?
Jack R. Woods's user avatar
11 votes
1 answer
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Could the James Webb Space Telescope detect biosignals on exoplanets?

The James Webb Space Telescope (JWST) which is slated to launch in 2018 will bring us a better view of exoplanets, but will it be sufficient to detect signs of life on at least some of those worlds? ...
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How exactly did JWST take a "selfie" of its own primary mirror, and what is the real purpose of this capability?

CNN's Webb telescope's first test images include an unexpected 'selfie' says only: The mirror selfie was captured by a special lens inside NIRCam that can image the primary mirror rather than what ...
uhoh's user avatar
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What are the black spots/blobs in JWST Jupiter's images?

Consider these two recent JWST images of Jupiter: Europa is shown as the black circle. In the second image, Europa's shadow can be seen near Jupiter's big red spot (white in the image, since it is in ...
Victor Stafusa - BozoNaCadeia's user avatar
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What is this object visible in the Chandra image of the Cartwheel galaxy that isn't visible in JWST image?

In the below images I aligned an image from Chandra of the Cartwheel galaxy over the image from JWST. The first is the Chandra image pasted on top, fully opaque. The second is just the JWST image, and ...
MVTC's user avatar
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Gravitational mirroring: Can we theoretically see the Milky Way using a telescope?

As I am watching the beautiful deep field picture of the James Webb Space Telescope. I noticed the gravitational lensing. So I asked myself whether it is possible somehow a successive cluster of ...
user50618's user avatar
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What causes the halo in JWST's new image of Jupiter?

Then new JWST image of Jupiter shows a small halo on the right side of the planet. What's causing this feature? I figure it could be that the planet is simply overexposed (or moving slightly during ...
user2944352's user avatar
9 votes
6 answers
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Why don't we just unshift the IR photos from Webb?

I’ve been going back and forth with peers on why image processing is done the way it is on the Webb Telescope. Based off some article, my understanding is that they have various filters that represent ...
lumenhippo's user avatar
9 votes
1 answer
986 views

Will JWST be as durable as the hubble telescope?

JW Space Telescope is designed for a 5-10 year mission duration. Seeing as Hubble and other space missions have paved the way for JWST for reliability issues, It even has zero friction gyro's with 100+...
bandybabboon's user avatar
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What is the projected range of the JWST to be able to detect exoplanet atmospheres?

Yesterday the K2 mission detected transit events of objects passing in front of a number of M dwarfs which could turn out to be rocky planets. If some of these planets host atmospheres, could the JWST ...
dualredlaugh's user avatar
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Which JWST instrument modes are compatible with observations of the bright trans-Earth planets Mars, Jupiter, and Saturn? Which aren't?

My comment says: ...answers to the Space SE question Can James Webb take pictures of our solar system? In what ways will they differ from/compliment those from Hubble? suggest that at some point JWST ...
uhoh's user avatar
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What would evidence of stars and galaxies significantly older than 13.8 billion years old look like? In what parts of space has it not been found?

The September 19, 2023 podcast with transcript Why the earliest galaxies are sparking drama and controversy among astronomers includes the following: An article published earlier this year in the ...
uhoh's user avatar
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What is this bright blue object taken by the Webb telescope?

From NASA - New Webb Image captures clearest view of Neptune's rings in decades: Does anyone know what the bright blue on the left top corner of the picture is? It is a reflection of sorts or is it a ...
DialFrost's user avatar
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8 votes
1 answer
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Why not build a swarm of space telescopes?

James Webb Space Telescope (JWST) has not yet started doing science, yet its successor LUVOIR is being discussed already. However I am curious; some countries have invested billions of dollars in ...
Sasha's user avatar
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8 votes
3 answers
322 views

In what measure James Webb Telescope "exceeded expectations"?

It is in all the news that the first images of James Webb Telescope "exceed expectations", but in what features? resolution?
Colim's user avatar
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1 answer
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What are the bright dots in some galaxies in the first JWST image?

In the first image released by the James Webb Space Telescope, some galaxies seem to have many bright dots - what are these? Young, huge stars? Supernovae? Just hot things behind the galaxy? (30 MB ...
2080's user avatar
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8 votes
1 answer
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General process of calculating what a telescope's diffraction spikes would look like?

I was reading this question about the JWST's diffraction spikes, and I was rather surprised by the magnitude of the 4 sets of diffraction spikes. The large hexagonal spike pattern I believe is formed ...
Ingolifs's user avatar
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8 votes
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Is there a standard deconvolution procedure to remove JWST's diffraction pattern yet? If so, would Arp 220 be a good candidate on which to try it?

Source: Webb captures the spectacular galactic merger Arp 220 Shining like a brilliant beacon amidst a sea of galaxies, Arp 220 lights up the night sky in this view from the NASA/ESA/CSA James Webb ...
uhoh's user avatar
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7 votes
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JWST First Image With Star 18x - Which image is from which mirror?

The James Webb space telescope first image showing the same star 18 times with the unaligned mirrors is great. How do they tell which image corresponds to which mirror? see Photons Received: Webb Sees ...
ZBwith3ARMs's user avatar
7 votes
1 answer
308 views

How to become proficient using the JWST pipeline?

I am trying to obtain proficiency in reviewing and analyzing JWST data. To that end, I have installed python jdaviz environment and files and JWST python environment and files. I am tinkering with ...
tckosvic's user avatar
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7 votes
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When is JWST's first light?

Is there an official estimate when the first light of the James Webb Space Telescope happens? I keep following the press releases from ESA and NASA, but I cannot recall that I saw any on that topic. ...
B--rian's user avatar
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7 votes
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How are the occurrence and nature of micrometeoroid impacts on JWST optics identified?

There are been recent news about a larger-than-expected micrometeoroid impact on the James Webb Space Telescope's optics. Apparently this was one of several impacts that have already been observed. ...
Roger Wood's user avatar
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7 votes
0 answers
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How are the aberrations seen in early JWST images corrected?

I found this image on space.com and it can also be found in NASA's JWST blog. This is one step in the process of aligning the 18 mirrors on JWST. A single relatively-isolated star has been selected. ...
Roger Wood's user avatar
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6 votes
1 answer
456 views

What parameters of the Big Bang model will have to be adjusted to account for JWST's observations of highly redshifted galaxies?

There are a lot of claims, on YouTube at least, that the James Webb space telescope have found too many to old/highly redshifted normal looking galaxies to fit easily into the Big Bang model. One such ...
Agerhell's user avatar
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6 votes
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Is this scaling of JWST halo reasonably correct

After thinking about accurately visualizing the size of the Andromeda galaxy I began to wonder about the halo orbit of the James Webb Space Telescope. Using an estimate of 1.5E6 km for halo width and ...
BradV's user avatar
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6 votes
1 answer
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How does the James Webb Space Telescope achieve a focal length of 131.4m?

How does the James Webb Space Telescope achieve a focal length of 131.4m ?
Sebastyen Laroche's user avatar
6 votes
1 answer
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What is the numerical aperture of the James Webb Telescope?

I was wondering what the NA of the James Webb telescope is: Based on this eq: R = λ / 2NA >> NA = λ / 2R Key Facts - James Webb Space Telescope - NASA λ = 0.6 - 28.5 microns = 0.6 - 28.5 x 10-6 ...
rul30's user avatar
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6 votes
2 answers
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JWST mirrors each can be "positioned in tip, tilt, piston, horizontal & vertical decentering and clocking". What does this mean?

This interesting paper by Robert Warden refers to each mirror segment on JWST as having six actuators providing six degrees of freedom in positioning (plus one more to tweak the curvature). These ...
Roger Wood's user avatar
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6 votes
2 answers
194 views

Will the James Webb Space Telescope need re-alignment of primary mirror segments?

I couldn't find an answer to this question. James Webb Space Telescope will align primary mirror segments and secondary mirror in space. Question is whether these will need re-alignment during the ...
akostadinov's user avatar
5 votes
2 answers
429 views

Question: By design, JWST cannot observe in the anti-sun direction. Is this due to Gegenschein backscatter?

This question has been reposted from Space Exploration Gegenschein is a faint bright spot in the zodiacal light, centered at the antisolar point. By ESO/Y. Beletsky - ESO, CC BY 4.0, https://commons....
Woody's user avatar
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What is the story behind this supposedly incredibly detailed image of the disk of Proxima Centauri attributed to the JWST?

Etienne Klein (@EtienneKlein)'s twitter account labels them as: Directeur de recherche @CEA_Officiel, producteur de « Science en questions » sur @franceculture, publie « L’esprit du corps » and ...
uhoh's user avatar
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5 votes
1 answer
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What is this curve, captured both in the Webb and Hubble images?

Any guesses what this might be? Source: tweet
chaimp's user avatar
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5 votes
1 answer
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Webb data pipeline explanations e.g. using the first five images?

The first 5 stunning results from the Webb Space Telescope are now available! And the raw data is available for them, e.g. via bulk download scripts or via the Mikulski Archive for Space Telescopes (...
nealmcb's user avatar
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"Quarter root of intensity" in coronographic plots

In excitement regarding the JWST release, I came across Krist et al, The JWST/NIRCam coronagraph: mask design and fabrication, within which there is the following plot: Fig. 9. Focal plane images ...
0xDBFB7's user avatar
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