James Webb Space Telescope Feed Post

ChrisAshford | JWST Cassiopiea A

This image uses narrowband NIRCAM images made by the NASA/ESA/CSA James Webb Space Telescope. The data were obtained from the Mikulski Archive for Space Telescopes at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127 for JWST. Images used were from the following NIRCAM filters: F150W F356W F444W I was practicing NB image processing today since the weather has been awful and I didn't have any of my own data. It's an amazing image with a scale of 0.063 arcseconds per pixel, and if you look carefully, you'll see a lot of galaxies in the background. There are also quite a few things in the image that could be artifacts that I've introduced, or they could be things seen in infrared that we don't normally see in our Astrophotos....not sure whether I over processed it. Nevertheless, it makes a nice image :) Wikipedia - [b]Cassiopeia A[/b] ([b]Cas A[/b]) ([url=https://upload.wikimedia.org/wikipedia/commons/transcoded/a/a0/Cassiopeia_%28spoken_word%29.ogg/Cassiopeia_%28spoken_word%29.ogg.mp3]listen[/url][url=https://en.wikipedia.org/wiki/File:Cassiopeia_(spoken_word).ogg]?[/url]) is a [url=https://en.wikipedia.org/wiki/Supernova_remnant]supernova remnant[/url] (SNR) in the constellation [url=https://en.wikipedia.org/wiki/Cassiopeia_(constellation)]Cassiopeia[/url] and the brightest extrasolar [url=https://en.wikipedia.org/wiki/Astronomical_radio_source]radio source[/url] in the sky at frequencies above 1 GHz. The supernova occurred approximately 11,000 [url=https://en.wikipedia.org/wiki/Light-year]light-years[/url] (3.4 [url=https://en.wikipedia.org/wiki/Parsec#Parsecs_and_kiloparsecs]kpc[/url]) away within the [url=https://en.wikipedia.org/wiki/Milky_Way]Milky Way[/url];[url=https://en.wikipedia.org/wiki/Cassiopeia_A#cite_note-Fesenetal2007-2][2][/url][url=https://en.wikipedia.org/wiki/Cassiopeia_A#cite_note-pop-sci-dec-2006-3][3][/url] given the width of the [url=https://en.wikipedia.org/wiki/Orion_Arm]Orion Arm[/url], it lies in the next-nearest arm outwards, the [url=https://en.wikipedia.org/wiki/Perseus_Arm]Perseus Arm[/url], about 30 degrees from the [url=https://en.wikipedia.org/wiki/Galactic_anticenter]Galactic anticenter[/url]. It is estimated that light from the supernova itself first reached [url=https://en.wikipedia.org/wiki/Earth]Earth[/url] near the 1690s, although there are no definitively corresponding records from then. Cas A is [url=https://en.wikipedia.org/wiki/Circumpolar_constellation]circumpolar[/url] at and above mid-Northern latitudes which had extensive records and basic telescopes. Its likely omission in records is probably due to [url=https://en.wikipedia.org/wiki/Interstellar_dust]interstellar dust[/url] absorbing optical wavelength radiation before it reached Earth, although it is possible that it was recorded as a sixth magnitude star 3 Cassiopeiae by [url=https://en.wikipedia.org/wiki/John_Flamsteed]John Flamsteed[/url]. Possible explanations lean toward the idea that the source star was unusually massive and had previously ejected much of its outer layers. These outer layers would have cloaked the star and absorbed much of the visible-light emission as the inner star collapsed. Image & Description by ChrisAshford.