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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Will Webb observe a sample of the outer solar system to estimate the population of objects that might endanger Earth?
the James Webb Telescope is incredibly sensitive to warm objects. But it has a lot more important things to do than a survey of the outer solar system looking for objects that might fall close to ...
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Astrometric alignment of JWST image
I have HST image and JWST image of galaxy mosaic.
HST wcs is correct as it was already updated with GAIA before.
But JWST wcs is shifted a bit as its wcs is not corrected.
So what I want is to correct ...
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What is the black gap layer in Jupiter's limb?
[Source: NASA/Webb]
On the rightmost edge of Jupiter, there is a black layer between the planet and the very top of its atmosphere.
Is this the day-night terminator effect, like when the clouds above ...
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conversion from magnitude to flux
I am using GalSim for creating mock galaxies in a magnitude range of 28-29. GalSim requires the input flux in units of photons/cm^2/s . I have used the halflight radii as per the value for this ...
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Flux unit conversion
I have a jwst nircam image of a galactic field. The science images are in units of MegaJansky per steradian (MJy/sr), and so the zeropoint is 28.08652 AB mag . When I ran sextractor on this image , I ...
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Luminosity function calculation
I have M_UV(absolute UV magnitudes) and redshifts of some high z sources and I want to fit UVLF for them.
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Co-adding IFU data cubes
I was able to get my hands on some NIRspec IFU data cubes from JWST, and I was trying to combine two adjacent FOVs for getting the complete picture of my system. I used CASA prior to this to remove ...
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GAIN in Sextractor
I'm using SExtractor for source detection from JWST CEERS NIRCam images. I'm using the fully reduced mosaics provided in CEERS website (The mosaics are on pixel scales of 0.03"/pix and are pixel-...
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PSF Matching Images from different filters
I have a fits images corresponding to different filters of JWST. I want to make sure they are PSF matched for accurate photometric color measurements by using SExtractor. I wanted to match them to ...
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SNR (Signal to noise ratio) from image
I have JWST images across 7 filters. I extracted sources by using SExtractor. How can I estimate the SNR of each source in each filter. Should I use flux/flux_err or use flux/background_rms. (flux and ...
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Using EAZY as photometric redshift estimation tool
I am new to JWST data analysis and currently trying to extract redshift of high redshift sources from the catalogue I created from SExtractor. I'm using EAZY (Brammer et al. 2008) for this purpose.
I ...
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Using prospector for jwst data
I am working with JWST data. I want to estimate the redshift of the sources I have identified with SEXtractor with the help of prospector. Can somebody guide me in this?
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How to find the minimum range at which some imaging payload/instrument can produce a clear image?
JWST's NIRCam can image deep sky objects so clearly. However if we notice the images of planets like Mars, Saturn or Saturn's's Moon-Titan, they don't appear to be much clear. Hence considering the ...
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Dual mode in SExtractor
I wanted to use SExtractor for source detection. I have 7 NIRCam filter data from the JWST CEERS catalogue. How can i proceed with the source detection. I read about using dual image mode in which a ...
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Using SExtractor for JWST data
I am new to this tool for catalogue creation(SExtractor). I want to know about how to set parameters for the extraction for JWST data.
The parameter file looks like this.
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Difference in field of view between JWST and Euclid
I was watching this video about the Euclid telescope. At the 8 minute mark he compares the field of vide of Euclid with that of the JWST, showing that the Euclid field of view is much larger.
While I ...
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What are these bands of dots on this Webb space telescope image?
The current image here has what seem to be periodic bands across the image made up of red dots. What are these?
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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 ...
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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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What's the official process for confirming then naming supernovae (e.g. Requiem and Encore)?
I saw this NASA Webb Telescope tweet:
Supernova 2: Galactic Boogaloo
In 2016, @NASAHubble saw a supernova named Requiem in a distant galaxy. Now Webb has found a second supernova named Encore — ...
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What is the biggest magnitude (faintest light possible) seen by JWST?
I'm doing some digging around ultra-diffused galaxies and would like to know what is the faintest visible light (biggest apparent magnitude) JWST can see. I have not been able to find it online.
Thank ...
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JWST Early Black Holes: Gas Collapsed To Metallic Hydrogen Core?
I was reading an article about early black holes found by JWST at Redshift 9. And saw that there was wonder at how large amounts of gas could collapse into a black hole as a theory.
So my question is ...
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Can you identify the source of this image of the Pacman Nebula (NGC 281)?
Months ago I downloaded this glorious image of the Pacman Nebula (NGC 281) in Cassiopeia. I have not been able to identify the source of the image (e.g., Hubble, James Webb Space Telescope, etc.) and ...
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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 ...
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Is it possible to detect lyman alpha blobs (LABs) with the lyman-break method?
LABs are luminous extended nebulae of hydrogen gas in the early universe (z ≥ 3) found in overdensities of LAEs (lyman-alpha emitters) and LBGs (lyman-break galaxies). I was wondering if LABs could be ...
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When should we expect atmospheric info from the most promising planets for life, Trappist-1e?
It seems like other exoplanets in the Trappist-1 system have been studied by JWST but perhaps most promising planet for life, Trappist-1e, has yet to get studied or at least have any published news.
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What could these LMC objects in this color-color diagram be?
I have performed a color-color and colour-magnitude plot of various sources detected in an LMC image (JWST NIRCAM F200W, F150W and F115W filters). I then also queried SIMBAD to collect relevant ...
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Obtaining Transit Spectrum for Celestial Bodies Using JWST NIRSPEC
I've recently been tasked with obtaining transit spectrum data for some fascinating celestial bodies, including Ceres, Enceladus, Ganymede, Io, and Titan. The goal is to compare their transit spectra ...
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Acetylene at Uranus? What's JWST's evidence and current thinking of how it's possible?
After about 03:22 in PBS Newshour's July 13, 2023 James Webb Space Telescope prompts scientists to rethink understanding of the universe JWST Interdisciplinary Scientist Heidi Hammel talks about ...
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Could macroscopic primordial black holes have created metals shortly after the big bang?
After seeing articles about the JWST like these two: https://news.cornell.edu/stories/2023/02/astronomers-discover-metal-rich-galaxies-early-universe
https://www.livescience.com/james-webb-space-...
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Does the other side of the Big Bang factor into JWST observations?
Our (roughly) 13.6 billion light year view to the point of origin (big bang) is just along a radial axis. Assuming most matter ejected in a (roughly) spherical pattern, the diameter of the universe is ...
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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 ...
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Are there any hints in the CMB as to why the James Webb telescope is finding galaxies larger than expected in the early universe?
"James Webb telescope detects evidence of ancient ‘universe breaker’ galaxies | Astronomy | The Guardian" https://amp.theguardian.com/science/2023/feb/22/universe-breakers-james-webb-...
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Angular extent of this composite Chandra / JWST image of the Tarantula Nebula?
I thought I’d ask this question here, as I couldn’t readily find the answer looking through online resources.
What is the angular extent of the composite Chandra / JWST image of the Tarantula Nebula ...
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Is the James Webb Space Telescope ever going to run out of thruster power to point it to the right direction?
As far as I know the only mechanism that our spacecrafts have to maneuver in space is gas thrusters.
Obviously pressurized gas is in a limited quantity on the JWST. What are the plans for when the ...
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Why is the latest Webb discovery of early-age universe considered so important?
The past week, news were flooding of an unexpected discovery of James Webb Space Telescope. In many articles it is mentioned that cosmologists cannot explain the formation of galaxies of this ...
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Why does one object (star?) in this JWST image have two sets of six+plus+two diffraction spikes but another, similar object nearby have only one?
CNN's February 24, 2023 Astrophysicist says 'there is nothing wrong with not knowing' is basically an opportunity for Neil deGrasse Tyson to give us a pep talk and reminder about the exciting process ...
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Can JWST see Proxima C?
I know that Proxima B is too close for Webb. But Proxima C is >1'' away from Proxima. So Webb could see it. There have been some unconfirmed images from earth. Besides there seem to be dust bands ...
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Can we use plain mirror as a secondary mirror in cassegrain telescope?
I was planning of making a telescope like JWST, just with plain mirrors, as bigger concave or convex are much expensive. The primary mirror would be totally made of plain mirrors configured like JWST. ...
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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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What accounts for a Lyman-break for all wavelengths shorter than 91.2nm if the Lyman limit is the highest energy photon that neutral hydrogen absorbs?
From this description of Lyman-break galaxies, I don't understand how:
...radiation at higher energies than the Lyman limit at 912 Å is almost completely absorbed by neutral gas around star-forming ...
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What data has JWST obtained of the Trappist-1 exoplanets and where is it? [duplicate]
I have been long waiting spectral data regarding the exoplanets around Trappist-1 and their atmospheres, and I was also long awaiting JWST's launch to get to know more about the system. However, now ...
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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 ?
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Is pointing a telescope at a random place a viable astronomical strategy?
Recently I happened to be on the MAST portal, looking at jwst data. I happened to come across 2 interesting targets, “random place” and “another random place”
This got me thinking. It’s almost ...
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How tall are the pillars of creation? (angular and physical) How bright are they? [duplicate]
NASA's October 19, 2022 NASA’s Webb Takes Star-Filled Portrait of Pillars of Creation shows a sparkly and beautiful infrared image of the Astronomical elephant trunks known as the Pillars of Creation.
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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 ...
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Redshift distance proportionality at high Z and need for "mighty mouse" galaxies?
Allegedly supported by some evidence from the new James Webb space telescope physicist Eric Lerner has written an article that have garnered some attention. He writes that:
"Put another way, the ...
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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 ...
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How much does foreground clumping affect the estimated sizes of high-redshift objects?
I've always converted angular to linear size by using the angular-diameter distance without really thinking about it. But in light of recent stories about high-$z$ galaxies observed by JWST being ...
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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 ...
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