Questions tagged [james-webb-telescope]
Launched in 2021, the James Webb Space Telescope (often called JWST) is a large, near infrared and visible space telescope with 18 mirror segments in Earth's L2 point. Use for questions about the telescope.
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How well is JWST doing on maintaining its Halo orbit?
I looked around a little bit online but did not find anything discussing how well JWST is doing with managing its orbit. I was wondering if there were any surprises or issues.
It's been out there ...
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What would be merits of placing space telescope after the asteroid belt or closer to the Kupier belt?
I want to know what difference does it make, in terms of observations made and the benefits for the astronomical society if we place a space telescope after the asteroid belt or near the Kuiper belt. ...
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Does the James Webb Space Telescope have a Two Line Element set?
How do you track the position of the James Webb space telescope? Does it have its own TLE, or...?
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How does the James Webb space telescope measure wind shear?
NASA.gov has an image of the James Webb space telescope's nircam tracking a high speed belt near Jupiter's equator. They measured the speed by looking at wind shears in millibars. How does Webb do ...
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Would electrically powered thrusters on JWST have made it last for decades longer?
Since the lifespan of the James Webb Space Telescope is determined by the amount of fuel it can carry for its thrusters, used to decelerate the reaction wheels used to orient the telescope, and since ...
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What is that black thing in center of every star in this JWST image?
I circled that black thing in this image with blue color:
The image above, which NASA released on Wednesday (July 6, 2022), represents 32 hours of observing time
from JWST's Fine Guidance Sensor.
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Would it be practical to position a telescope like JWST at Sun-Earth L4 or L5?
During a discussion of Lagrange points I was asked why we didn't put JWST at SE L4 or L5 since they are less unstable than L2. I thought a bit and came to think that the Earth gravity driven Halo ...
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How "specularly" and therefore spectacularly will JWST reflect sunlight? Will we be watching for JWST flares?
JWST has a giant sunshield made from mostly parallel layers of metalized polymer film that are sufficiently tensioned so as not to touch each other, though I'm not sure how taut or flat they are:
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What is the advantage of optical astronomy over infrared astronomy in space telescopes?
The Habitable Worlds Observatory, the proposed successor to the James Webb has an identically sized 6.5 meter mirror but operates primarily in visible light. Infrared telescopes like Webb have the ...
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How close can a spacecraft get to the Sun if it is limited solely by passive cooling?
The Parker Solar Probe’s trajectory will take it within 8.5 solar radii of the sun’s photosphere. Its instruments, hiding in the shadow of the alumina-coated composite sun shield, will bask in 29 °C ...
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What was so hard about the washer nuts on the JWST?
In a YouTube "Short", Dr. Becky explains that a problem with ten washer nuts wound up adding 800 days and $800 million to the JWST. The problem is that they came loose in the shake test, and ...
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Are the 10 identical stars in this JWST image one of the same?
Consider:
In this image you can see a cluster of 3 stars in the bottom left, one big star in the middle up and many more identical stars scattered throughout the image.
Are they all the same star? ...
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ET come home. Is the inter-manifold transfer of JWST between Sun-Earth L2 and Earth-Moon L1 within the capability of existing propulsion systems?
Context: JWST is considered un-repairable in its current L2 location for a number of reasons:
Diagnosis is difficult since JWSR has no “selfie” capability. This makes planning for any repair mission (...
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Could the James Webb Resolve Earth?
Hypothetically, if one were to point the James Webb at Earth:
Could it be focused in such a way that the entire Earth was in it's FOV, or is it too close?
If this were possible, what would be the ...
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Are L1 and L2 orbital periods always half the orbital period of the massive bodies?
Are L1 and L2 libration point orbital periods always half the orbital period of the massive bodies?
The halo orbital period of JWST is a half a year. https://webb.nasa.gov/content/about/orbit.html
The ...
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Rotation and orientation of James Webb's mirror from ground stations
There are definitely pre-determined plans in the agenda of the James Webb telescope to take images from the universe, but if there is a need for any reason (intentional or emergency) to change the ...
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How common is it for spacecraft to have "selfie" capability?
According to ESA:
A sudden small power reduction was observed in a solar array of Sentinel-1A, orbiting at 700 km altitude, at 17:07 GMT on 23 August. Slight changes in the orientation and the orbit ...
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Is JWST actually in a Lissajous orbit? What will it look like? Implications for station-keeping?
Note: for lots of great background related to this question, see lagrangian points - The design of the halo orbit of the James Webb Space Telescope - Space Exploration Stack Exchange
There are ...
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Is JWST Halo orbit prograde or retrograde and why?
There is confusion in my mind over the direction of JWST’s halo orbit, depending in the source of graphics.
Observing from the Earth, does JWST orbit clockwise or counterclockwise around the antisolar ...
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Could you bounce a tennis ball off of the James Webb sunshield?
News articles keep referring to the James Webb Space Telescope's sunshield as "about the size of a tennis court", which raises the question: could it function as a tennis court? Or, more ...
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If James Webb goes "over the hill" is it gone for good?
James Webb is in a Halo orbit around Earth's L2 point. It is in a gravitational saddle: two directions are stable ("up-down" and "front-back"). The "in-out" direction is ...
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Would it be possible to receive the transmissions from JWST as an amateur?
Would it be possible to receive the transmissions from JWST (James Webb Space Telescope) as an amateur, building your own antenna?
Would the transmissions be encrypted?
One source cites it using: S-...
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How redshifted galaxies will JWST be able to detect? [closed]
I see that the MIRI camera/spectrograph on JWST has an operational wavelength span between 5 and 28 micrometers. Now visible not redshifted light has wavelengths between 400 and 700 nanometers. If ...
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Can the JWST look at Earth? What would it see? [duplicate]
There's a few questions on the site about whether we can see the James Webb Space Telescope from Earth (i.e. here and here), but I'm wondering about the opposite - can we see Earth using the JWST?
I ...
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Why does JWST make images of planets from solar system?
NASA has already made images of planets from the solar system
before. So why is NASA/ESA making images of planets from the solar system
by using the JWST instead of exploring unseen parts of universe?...
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Why was JWST cancelled in 2011?
I saw this table in this section:
In the third column from the bottom, it says "Proposed cancel":
Why so?
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Can JWST come in for a pit stop? Is the fuel supply on JWST adequate for a transfer to an Earth Moon libration point to allow repairs?
The James Webb Space Telescope is generally considered to be in an unserviceable location at SEL2.
If servicing becomes necessary, is it possible for the JWST to use a low energy heteroclinic transfer ...
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Why is the hot part of Webb's MIRI cryocooler in the 300K area?
Longer wavelengths require cooler temperatures to detect efficiently. The MIRI detects all the way out to 25 μm and so needs to be cooled to 7 K.
Webb can passively cool down to 40 K with its sun-...
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Can James Webb take pictures of our solar system? In what ways will they differ from/compliment those from Hubble?
I am curious to know whether the James Webb Space Telescope will be able to take pictures of our own planets like Jupiter / Saturn like Hubble did.
If yes, then how different are these images expected ...
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Gyros for long term attitude control
James Webb telescope is limited to a 10 year service life by its fuel, as I understand it.
While propellant would be required to translate the craft for orbital maneuvering, could pure attitude ...
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Why didn't JWST include any sensors capable of blue and green visible wavelengths
JWST wavelength sensing starts at 600nm, corresponding to red/orange visible light, and then into the IR. It seems there is no sensor or filter included below 600nm meaning that green and blue light ...
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Could any of the JWST instruments image the rings around 10199 Chariklo?
The asteroid 10199 Chariklo orbits between Saturn and Uranus. It has two rings with radii 386 and 400 km and widths of about 6.9 km and 0.12 km respectively. It is currently 15.94 AU from Earth. Do ...
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How much margin does JWST have for station keeping in Halo orbit?
How much margin in $\frac{m}{s}$ does JWST have for station keeping in Halo orbit?
JWST must always stay on the earth side of the L2 saddle since thrusters only point towards the sun. Also` solar ...
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How much of the sky can the JWST see?
According to the JWST FAQ:
To turn and point at different objects in space, Webb uses six reaction wheels to rotate the observatory. The reaction wheels are basically flywheels, which store angular ...
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JWST Gravitational lensing
In the JWST deep field image we see gravitational lensing but it is not there in stefans quintent image of much more massive galaxy cluster.
What are the criteria for seeing magnified images of ...
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Visualizing halo orbits
I'd like to visualize JWST's orbit (or any halo orbit that resembles it) preferably in Python. Does anyone have any code or resource I could read? Thanks in advance!
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Why would the James Webb Space Telescope need adaptive optics outside the atmosphere?
Adaptive Optics is generally used with ground telescopes to correct for atmospheric distortions or seeing. Right now it is used mostly in the infrared but is starting to be used in longer visible ...
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If JWST can look into 13 billion years past then why it cannot check sun formation which happened only 4.603 billion years ago?
If JWST can look into past then why it cannot find how the sun formed 4.603 billion years back?
I heard that JWST will process infrared light waves to make them more clear to the human eye but not it ...
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Has JWST done its first station keeping yet?
Has JWST done its first station keeping yet? The last burn I know about was the MCC2 burn on Jan24; more than 21 days ago; and that was a pretty long burn with a $\Delta v$ of 1.6 m/sec or 160 cm/sec, ...
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Is it practically possible to replace deformed mirror segments after impact in a service mission? [duplicate]
After reading the first articles about Webb being hit by micrometeorites/ dust and that this was more than expected, I was wondering whether it would be possible to have a service mission to replace ...
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Interesting diffraction pattern on JWST composite false-color image released today (July 11) at Biden preview - how does this arise?
There was an earlier question on the diffraction pattern in the Mar 16 test image that was mainly explained by the hexagonal shape of the individual mirror segments. Today's image has similar ...
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How did the JWST take a selfie?
During the alignment of JWST primary mirrors, this selfie was taken:
(source: NASA)
I think we're seeing here the primary mirrors, with the secondary in the center and the reflection of the support ...
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What kind of hardware and software does the James Webb space telescope computer use?
What kind of software, operating system, database, processor, architecture, antenna used for communication back to Earth, basically what computer does it use.
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What will now happen with Hubble?
The James Webb Telescope just started it’s scientific work. The amazing pictures and information is definitely better than Hubbles. What will now happen with Hubble?
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Why did NASA release JWST image of SMACS 0723 one day before the scheduled time?
A few hours ago, NASA released JWST image of galaxy cluster SMACS 0723
one day before the scheduled time:
President Joe Biden unveiled this image of galaxy cluster SMACS 0723, known as Webb’s First ...
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Hubble vs JWST telescope
Can you quantify how much better JWST is compared to Hubble?
For instance, from what distance can each "see" (differentiate) a sun-like star?
Maybe there are other measures.
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Diffraction artifact on the March 16, 2022 JWST aligned test image
On March 16, 2022 we were treated to the first image from the JWST of a star, where all 18 segments were aligned and in common focus. What a wonderful photo:
(Source: Webb Twitter. Full 18 MP ...
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Are first official science images of JWST are most far distant images ever taken by space telescope?
In JWST, it says:
NASA has scheduled the first official science images release event for Tuesday, 12 July 2022 at 10:30 am EDT/usa.
Are first official science images of JWST are most far distant ...
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Are these latest anticipated images of JWST released to public?
I came across this line from here:
These latest anticipated images (around 10-20 predicted) however are said to be so beautiful
that Associate Administrator for NASA’s Science Mission Directorate, ...
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How long does NASA take to post process JWST images?
My question came from this comment.
How long does NASA take to post process JWST images?
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