Feb 5, 2021
The tip of the “wing” of the Small Magellanic Cloud galaxy is dazzling in this 2013 view from NASA’s Great Observatories. The Small Magellanic Cloud, or SMC, is a small galaxy about 200,000 light-years way that orbits our own Milky Way spiral galaxy.
The colors represent wavelengths of light across a broad spectrum. X-rays from NASA’s Chandra X-ray Observatory are shown in purple; visible-light from NASA’s Hubble Space Telescope is colored red, green and blue; and infrared observations from NASA’s Spitzer Space Telescope are also represented in red.
The spiral galaxy seen in the lower corner is actually behind this nebula. Other distant galaxies located hundreds of millions of light-years or more away can be seen sprinkled around the edge of the image.
The SMC is one of the Milky Way’s closest galactic neighbors. Even though it is a small, or so-called dwarf galaxy, the SMC is so bright that it is visible to the unaided eye from the Southern Hemisphere and near the equator. Many navigators, including Ferdinand Magellan who lends his name to the SMC, used it to help find their way across the oceans.
Modern astronomers are also interested in studying the SMC (and its cousin, the Large Magellanic Cloud), but for very different reasons. Because the SMC is so close and bright, it offers an opportunity to study phenomena that are difficult to examine in more distant galaxies. New Chandra data of the SMC have provided one such discovery: the first detection of X-ray emission from young stars, with masses similar to our sun, outside our Milky Way galaxy.Image Credit: NASA/CXC/JPL-Caltech/STScILast Updated: Feb 5, 2021Editor: Yvette Smith
“Did you know that the Hubble Space Telescope doesn’t have any color cameras on it? Its sensitive electronic detectors count each bit of light that hits the camera, but don’t directly record the color of the light. Hubble uses special filters that allow only a certain range of colors through. Once the unwanted light has been filtered out, the remaining light is recorded. As a result, every image Hubble sends to Earth is in black and white.
Hubble scientists and image processors create Hubble’s beautiful color images by adding an individual color to each separate black-and-white filtered image. These single-color images are then combined to make the final picture. The colors in Hubble images aren’t always what we would see if we were able to visit the imaged objects in a spacecraft. We use color as a tool, whether it is to enhance an object’s detail or visualize what ordinarily could never be seen by human eyes.”
The Meaning of Light and Color (hubblesite.org)
Neither did TV cameras from day one. Colour image hits a complex prism assembly , light is split 3 sometimes 4 way (R, G, B & Y). The system has appropriate optical colour filters in the light paths, then individual images are intercepted by state of art (at the time) light to electronic signal detectors and recombined (encoded). Reverse process takes place at the receivers’ end..In the early decades all signals and processing was in the analogue form but later digital became the world wide standard.
Color movies of today use the same process in reverse.
A 3 or 4 way prism receives the individual color image streams and reflect the composite color image; e.g. IMAX.
Yes, astronomers figured out a long time ago that “standard” color emulsions (e.g. Kodachrome) have various dips in their spectral sensitivity. Kodachrome is not as sensitive to line radiation from doubly ionized oxygen (those pesky forbidden lines…). Lick Observatory pioneered using three filters, black and white film, and then using dye transfer printing to capture imagery from ionized regions such as the Crab and Orion sword. The difference is dramatic when comparing old 48-inch Schmidt imagery with the Lick dye transfer prints. Using the same technique with CCDs, filters and imaging processing today. Still have to calibrate the spectral response regardless of technique used.
Would be cool and informative if they started adding a color scale legend to the images.
From the above article, reformatted to be less cluttered:
Mr. jmorpuss: Surely you don’t mean these images are being adjusted??!! By NASA?? So, the color is evidence of AGW??!!
That is CliSci reverse engineering for you.
Yes, a lovely image of an area of active star formation in a neighbouring galaxy. Humbling for all humanity to see the myriad of tiny galaxies of various hues scattered throughout the background of this minute portion of the sky. The spiral ones immediately stick out but there are many of indeterminate shape and form out there too.
I saw a program yesterday about galaxies colliding, and it seems that our galaxy, the Milky Way, has a collection of stars that are traveling around the center of the galaxy in the opposite direction from the majority of stars.
So I guess the Milky Way had a collison with a galaxy that was rotating in the opposite direction to the Milky Way when they collided in the past.
You may be talking about something else, but the Sagittarius Dwarf galaxy is an interesting orbiting remnant of a mostly-absorbed satellite galaxy.
https://en.wikipedia.org/wiki/Sagittarius_Dwarf_Spheroidal_Galaxy
Tom, try this, point 2 fingers away from you and rotate in the same direction, say clockwise . now while still rotating, point them at each other, your finger seem to be now rotating in opposite directions. the only thing that’s changed is or perception. Just like high and low pressure systems here on Earth, Highs rotate down and lows rotate up in the same direction.
All it takes is an galaxy collision against the rotation of our galaxy. Stars and solar systems arriving at speed would get caught by the galactic center and orbit in the opposite direction.
One assumes that over time, these counter flow orbits will slowly be reduced or eliminated as head on collisions neutralize the counter orbiters.
An interesting satellite galaxy of the Milky Way. Even being pretty small, it gets shaken up by tidal forces working on it from the MW, and so a respectable amount of star formation is taking place (even more star formation is taking place in the Large Magellanic Cloud). It will eventually get absorbed by the MW, but it may take a very long time.
Move over Man in the Moon, there’s a man in the Small Magellanic Cloud. It is just right of center in the photo. It has a chin, mouth, nose, eyes, and a full set of hair.
That’s what I noticed also.