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The James Webb Space Telescope and stuff


Streetwind
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The thing I find amazing when looking at these two images is how some of the lensing that is so readily apparent in the Webb photo, was also visible in the Hubble image.

Shows just how good Hubble is - and how much more info we can get from Webb!

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There's a little 'cap' evident over the blurry galaxy to the right of the bright white star/galaxy in the center of the image.  It's the same red & orange semicircular lensed galaxy just above right of center in the Webb image below.

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If you want to know more about the images Webb posted today; they have the pictures up, along with WORDS!!!

Stephan's Quintet 

  • In an enormous new image, NASA’s James Webb Space Telescope reveals never-before-seen details of galaxy group “Stephan’s Quintet”
  • The close proximity of Stephan’s Quintet gives astronomers a ringside seat to galactic mergers, interactions
  • Webb’s new image shows in rare detail how interacting galaxies trigger star formation in each other and how gas in galaxies is being disturbed
  • The image also shows outflows driven by a black hole in Stephan’s Quintet in a level of detail never seen before
  • Tight galaxy groups like this may have been more common in the early universe when superheated, infalling material may have fueled very energetic black holes

 

Cluster SMACS 0723

  • President Joe Biden unveiled this image of galaxy cluster SMACS 0723, known as Webb’s First Deep Field, during a White House event Monday, July 11
  • Webb’s image covers a patch of sky approximately the size of a grain of sand held at arm’s length by someone on the ground – and reveals thousands of galaxies in a tiny sliver of vast universe
  • Webb’s sharp near-infrared view brought out faint structures in extremely distant galaxies, offering the most detailed view of the early universe to date
  • NASA and its partners will release the full series of Webb’s first full-color images and data, known as spectra, Tuesday, July 12, during a live NASA TV broadcast

 

Southern Ring Planetary Nebula

  • NASA’s James Webb Space Telescope has revealed details of the Southern Ring planetary nebula that were previously hidden from astronomers. Planetary nebulae are the shells of gas and dust ejected from dying stars.
  • Webb’s powerful infrared view brings this nebula’s second star into full view, along with exceptional structures created as the stars shape the gas and dust around them.
  • New details like these, from the late stages of a star’s life, will help us better understand how stars evolve and transform their environments.
  • These images also reveal a cache of distant galaxies in the background. Most of the multi-colored points of light seen here are galaxies – not stars.

Wasp-96 b Steamy Atmosphere GRAPH!!!!

 

  • Webb’s enormous mirror, precise instruments joined forces to capture most detailed measurements of starlight filtering through atmosphere of a planet outside our solar system to date
  • The spectrum of light – which contains information about the makeup of a planetary atmosphere 1,150 light-years away – reveals distinct signature of water
  • The strength of the signal that Webb detected hints at the significant role the telescope will play in the search for potentially habitable planets in coming years
  • Webb’s powerful new view also shows evidence of haze and clouds that previous studies of this planet did not detect

Carina Nebula - Cosmic Cliffs

  • NASA’s James Webb Space Telescope reveals emerging stellar nurseries and individual stars in the Carina Nebula that were previously obscured
  • Images of “Cosmic Cliffs” showcase Webb’s cameras’ capabilities to peer through cosmic dust, shedding new light on how stars form
  • Objects in the earliest, rapid phases of star formation are difficult to capture, but Webb’s extreme sensitivity, spatial resolution, and imaging capability can chronicle these elusive events

 

 

 

...

 

(*um... if it's not clear: you have to follow the links to find more than the highlights!  Lots and LOTS of words!)

Edited by JoeSchmuckatelli
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22 hours ago, Minmus Taster said:

I'm confused, the image is stunning but is it infrared or visible light? NASA  did say in press releases that the image would be "full color".

Modern telescopes record the images as data (how many photons hit each location in the detector) and then images for human viewing are generated from that. Color is often assigned to make it look prettier or to emphasize aspects of the image for study. Since Webb can detect infrared, much of what it sees would not normally be visible to us at all but is depicted in colors we can see to make it useful to us. 

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MIRI has several operational modes that include spectroscopy, photometry and filtering. See https://jwst-docs.stsci.edu/jwst-mid-infrared-instrument

Colours can be achieved by various methods, in the end it is assigning colours to wavelengths and thus creating a palette. Technically, it goes down to rotating filters for certain wavelengths (colours) in the way and take a monochromatic raw image, rotate, repeat. Each image is assigned a colour channel and the stack combined. There's of course more to it for such an outstanding quality.

https://jwst-docs.stsci.edu/jwst-mid-infrared-instrument/miri-instrumentation/miri-filters-and-dispersers

Though the principle is simple (hobby astronomers do it the same way), every aspect of this observatory is a masterpiece in engineering.

Edit: A few years ago there were hobby astronomers here on the forum. Even recall a guy who ground his own mirrors.

If the raw images are there for download one can try one's own for example with a software like PixInsight, but needs a little basic astronomy knowledge.

Edited by Pixophir
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On 7/11/2022 at 6:40 PM, Minmus Taster said:

I'm confused, the image is stunning but is it infrared or visible light? NASA  did say in press releases that the image would be "full color".

The answers above are fantastic - and there is a segment about how they get the images to work in the Webb video I linked to (or cribbed about) above.  I think it's about 1/2 way through 

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JWST does grant us one notable exception to "false color" qualms: For objects receding from us at certain speeds (= at certain distances), visible light emissions are redshifted into JWST's range, so "false" color images can result in something close to what your eyes would see from up close. (I don't have the background to identify those speeds/distances myself, unfortunately.)

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How sharp would be a look from Webb at the closer stars ?

I mean, those obviously very far stars are a few pixels wide... How large would be, say, like, Proxima Centauri ?

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21 hours ago, Pixophir said:

The channels are chosen on purpose. They actually reflect physical properties of the observed area.

seems like you would just shift the frequencies over towards the visible part of the spectrum. you see rgb but what you are really seeing is 3 different ir frequency bands.  

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1 hour ago, Nuke said:

seems like you would just shift the frequencies over towards the visible part of the spectrum. you see rgb but what you are really seeing is 3 different ir frequency bands.  

Misunderstanding, no shifting, no RGB.  Has nothing to with mapping of colours, which is just agreement. I reacted to "false colours", because there is no "false".  For visualization, certain bands were mapped to colours. I don't know which ones (edit: but pls see link below), maybe they tell us or I have overheard because I didn't watch all the videos.  Btw., Hydrogen alpha, often mapped to red, actually looks red to human eye. One can actually see a slightly pink tint in the Orion Nebula, for instance. Plays no role here because too short wavelength (650nano-m) for JWST, just mention it for clarification.

The principle is, the filters only let certain wavelengths pass. That window for one filter can be wide (broad) or narrow, with pretty steep edges with these type of filters. These wavelengths, cleverly chosen, correspond directly to spectral properties, (e.g. excitement states of elements) of the observed matter. That's what they are for. That's how one identifies areas where young stars form, or dust clouds excited by the radiation of stars behind them, etc pp. There are broad- and narrow-band filters, combined they offer a wide range of well defined observations in pre-defined wavelengths. Each image, taken with one filter, is monochrome. It will be mapped to colour, for visualization, and the colour channels then combined to a nice colourful show-off.

Pop science link, sounds reasonable:

https://www.inverse.com/innovation/how-does-nasa-process-jwst-images

Quote

To get from a black and white image to a color one, the processors work on each filter, with shorter wavelengths generally assigned bluer colors and longer wavelengths assigned redder colors.

they say. This may be just for the press images, later on people with observation time will choose their own wavelengths and combinations and do their own evaluation.

 

Edited by Pixophir
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Spoiler

Of colored filters.

Imagine you have a set of colored spectacles.

You put on the green one.
"What's that? Something funny, like a tail with spiked mace at the end. It's dangling! So funny!"

You put on the blue one.
"What's that? Paws? Somebody's paws? With sickles?? Amazing..."

You put on the red one.
"Wut? Jaws?? Hanging in air and clicking??? What the hex is going on here?????"

You take off the colored spectacles.

Spoiler

"AAAAAHHHHHHH !!! IT'S RIGHT IN FRONT OF ME !!!!!!!"

cute-colorful-monster-cartoon-character-

Space photos work same way.

 

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2 hours ago, Moritz Space said:

I hope we'll also get pictures of the planets in our solar system

We will!

JWST cannot image Earth, Venus, or Mercury because it needs to keep its mirror pointed away from the sun. But it will be able to image Mars and objects in the asteroid belt and all of the dwarf planets and all of the giant planets.

It won't produce the highest-resolution photos of all time, mind you. Despite its sensitivity, its photos of Saturn won't be as good as the ones taken by Cassini and its photos of Jupiter won't be as good as the ones taken by Juno. But it will be able to probe into infrared which will tell us a lot more new things. 

This is the resolution with which Hubble sees Saturn:

heic1917a.jpg

JWST can gather six times as much light. 

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2 minutes ago, sevenperforce said:

We will!

JWST cannot image Earth, Venus, or Mercury because it needs to keep its mirror pointed away from the sun. But it will be able to image Mars and objects in the asteroid belt and all of the dwarf planets and all of the giant planets.

It won't produce the highest-resolution photos of all time, mind you. Despite its sensitivity, its photos of Saturn won't be as good as the ones taken by Cassini and its photos of Jupiter won't be as good as the ones taken by Juno. But it will be able to probe into infrared which will tell us a lot more new things. 

This is the resolution with which Hubble sees Saturn:

heic1917a.jpg

JWST can gather six times as much light. 

Can it do better pics of Uranus, Neptune or their moons than the ones the Voyagers took?

Edited by Beccab
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Just now, Beccab said:

Can it do better pics of Uranus, Neptune or their moons than the ones the Voyagers took?

Probably not better in the sense of absolute resolution. Voyager 2 came within 4950 km of Neptune during its flyby, close enough for its Imagine Science System cameras to achieve 500 meter resolution. We are 19 AU away from Neptune; you would need a primary mirror 35% larger than the dwarf planet Ceres to match that resolution from Earth's location.

Voyager 2 only came within 84,000 km of Uranus, so the resolution during that flyby was not as high as the Neptune flyby. Even so it's not much better; you would need a primary mirror just slightly smaller than Ceres to match that resolution from Earth's location.

However, JWST can take more pictures of Uranus and Neptune, and it can take them over a longer period of time, and it can take them in a broader spectrum, allowing us to see deeper. We can monitor weather and identify cloud layers and all kinds of cool things.

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15 minutes ago, Moritz Space said:

jupiterwebb.jpg Just saw that there has been a picture of Jupiter which was not published yesterday but in a summary afterwards.

Wow! 

https://www.newscientist.com/article/2328348-james-webb-space-telescope-team-quietly-releases-a-picture-of-jupiter/

"Taking pictures of Jupiter was part of a test to make sure that the observatory could track objects moving at high speeds through the solar system. Jupiter was the slowest – but largest and most spectacular – of nine moving targets used for these tests, and it showed that objects can be tracked even with a bright planet bouncing light into the cameras. The tests demonstrated that JWST is even better than expected at tracking fast-moving objects, which will be particularly useful for studying comets, near-Earth asteroids and even interstellar objects."

 

 

...  WAIT - What are the other 8 targets, and where are the images?!? 

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jupiter_hi_res_atmo-1.png

obs1_f277w.gif

But just how fast can an object move and still be tracked by Webb? This was an important question for scientists who study asteroids and comets. During commissioning, Webb used an asteroid called 6481 Tenzing, located in the asteroid belt between Mars and Jupiter, to start the moving-target tracking “speed limit” tests.

Webb was designed with the requirement to track objects that move as fast as Mars, which has a maximum speed of 30 milliarcseconds per second. During commissioning, the Webb team conducted observations of various asteroids, which all appeared as a dot because they were all small. The team proved that Webb will still get valuable data with all of the science instruments for objects moving up to 67 milliarcseconds per second, which is more than twice the expected baseline – similar to photographing a turtle crawling when you’re standing a mile away. “Everything worked brilliantly,”

From the blog (Above)

Also:

JWST Commissioning Data Highlights - MAST Data Holdings - MAST (stsci.edu)

 

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10 hours ago, sevenperforce said:

We are 19 AU away from Neptune; you would need a primary mirror 35% larger than the dwarf planet Ceres to match that resolution from Earth's location.

Challenge accepted

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