Image Credit: NASA, ESA, and The Hubble Heritage Team (STSci/AURA) The Horsehead Nebula in Infrared from Hubble Also note how aesthetically pleasing the image is despite it not being just optical light: Here is an image of the M82 galaxy using X-ray data from Chandra, infrared from Spitzer, and visible light from Hubble. Just like infrared data can be made into something meaningful to human eyes, so can each of the other wavelength of light, even X-rays and gamma-rays. When we combine images taken at different wavelengths of light, we can get a better understanding of an object, because each wavelength can show us a different feature or facet of it. There are many phenomena which can only be seen, for example, in the X-ray part of the spectrum, or in the ultraviolet. Here’s another compelling argument for telescopes that see things other than visible light – not everything in the universe emits visible light. See also this more technical page on Hubble image processing. Hubblesite also has this feature on how “natural color” imagery is created. Here is a sub-page specific to creating an image using infrared light. Use its left menu to click through the short presentation. ![]() This is my favorite feature (from ) about how Hubble images are colored, and I highly recommend reading through it. Sometimes colors are chosen to make them look as our eyes would see them, called “natural color,” but not always. Most often this is to highlight interesting features of the object in the image, as well as to make the data more meaningful. Hubble images are all false color – meaning they start out as black and white, and are then colored. The gorgeous images we see from Hubble don’t pop out of the telescope looking like they do when you view them on the web. The infrared data that will come from JWST can be translated by computer into something our eyes can appreciate – in fact, this is what we already do with Hubble data. ( This page has detailed info if you want to read more about them.) JWST has incredibly sensitive, state-of-the-art detectors in its cameras. JWST will take much sharper images than Hubble at infrared wavelengths, and it has comparable resolution at the visible wavelengths that JWST can see. On both of these counts, JWST is very similar to, and in many ways better than, Hubble. The beauty and quality of an astronomical image depends on two things: the sharpness of the image and the number of pixels in the camera. But the truth is that even though JWST sees mostly infrared light doesn’t mean it won’t take beautiful images. JWST actually will see a bit of optical light: red and orange. NASA, ESA/Hubble and the Hubble Heritage Team The ghostly outlines of the pillars seem much more delicate, and are silhouetted against an eerie blue haze. In this ethereal view the entire frame is peppered with bright stars and baby stars are revealed being formed within the pillars themselves. This image shows the pillars as seen in infrared light, allowing it to pierce through obscuring dust and gas and unveil a more unfamiliar - but just as amazing - view of the pillars. The NASA/ESA Hubble Space Telescope has revisited one of its most iconic and popular images: the Eagle Nebula’s Pillars of Creation. Things like: stars and planets being born in clouds of dust and gas the very first stars and galaxies which are so far away the light they emit has been pushed into the infrared, and the chemical fingerprints of elements and molecules in the atmospheres of exoplanets. To summarize, there are things Hubble can’t see that we want to know more about, and we need an infrared telescope to learn about them. ![]() ![]() We actually have blogged about them here on Blueshift, and have since adapted what we wrote into the current science pages on the JWST site. There are legit scientific reasons for JWST to be an infrared telescope. (Spoiler: it will see a lot of things even better.) Why would NASA build something that isn’t going to capture beautiful images exactly like Hubble does? The short answer to this is that JWST will absolutely capture beautiful images of the universe, even if it won’t see exactly what Hubble does. I get a lot of questions asking why the James Webb Space Telescope is infrared, and how its images can hope to compare to the (primarily) optical Hubble Space Telescope.
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