See! New Image From Webb Telescope Reveals Rare Galaxy Near Milky Way
Raw data from the James Webb Space Telescope gave a stunning image of a nearby galaxy, with a little help from an unofficial photo processor.
“I chose NGC 1365 because it was the most recent target of interest that the Space Telescope Science Institute, or STScI (the organization that runs JWST) released public images of,” Redditor u/SpaceGuy44, a graduate student in astronomy at a University of California, says Reverse.
The Great Barred Spiral Galaxy, officially known as NGC 1365, is 56 million light-years away, and it was one of the galaxy samples astronomers chose for some of Webb’s earliest observations, in the goal of learning more about nearby star formation. of the universe. NGC 1365 is a perfect candidate, because it’s a star-forming galaxy with an actively feeding supermassive black hole at its center, and it happens to be “face-on” toward Earth, so that astronomers can see its elaborate double-barred spiral structure in all its glory.
In most barred spiral galaxies – including, most likely, our own Milky Way – a bar-like structure made of older, less metallic stars extends down the center of the spiral. About two-thirds of all spiral galaxies have bars, but NGC 1365 is a rarer specimen: it has of them bars, one inside the other: an outer bar extending horizontally across the galaxy and an inner bar extending from the 10 o’clock to 4 o’clock positions.
The complex structures of bars and spirals are formed, in part, by stars, gas, and dust orbiting the galactic center at different speeds, forming waves of higher and lower densities that eventually become bars and spirals. spirals we see in galaxies like NGC 1365. And the gravity of NGC 1365’s bars can help pull matter toward the center of the galaxy, fueling the formation of new stars and feeding the ever-hungry black hole at its heart.
The first image, captured with Webb’s NIRCam instrument, shows light from the galaxy in near-infrared wavelengths; the second, from the MIRI instrument, shows a longer-wavelength mid-infrared view.
Unlike the striking color images that Webb’s official processing team has made public over the past few weeks, the builds that u/SpaceGuy44 are talking about are in a data format called FITS (Flexible Image Transport System).
According to NASA, “FITS is the most widely used data format in astronomy for transporting, analyzing, and archiving scientific data files. FITS is much more than just an image format (such as JPG or GIF) and is primarily designed to store scientific data. sets consisting of multidimensional arrays (images) and two-dimensional arrays organized into rows and columns of information. »
In other words, although anyone can download a FITS file from the Webb archive, you need specialized software to convert the file to a format that image-editing software like Photoshop or GIMP can handle. From there it’s a matter of selecting red, green and blue filters and aligning the image.
“You need some skill with photo editors,” says u/SpaceGuy44, “but I just started with GIMP a month ago and I think I’ve gotten pretty good with it.”
File conversion software, including Fits Liberator and SAO DS9, is publicly available, and there are online tutorials (including several hosted by STScI).
“I would say most of the people processing these images are amateurs, unless the images are released by NASA itself or another research team,” says u/SpaceGuy44. “Although I’m not an amateur, I just had a lot of passion and free time to do it since I was on summer vacation after grad school.”