What red galaxies are there in the universe?

This is the Rose Nebula, not a galaxy. The Rose Nebula (NGC 2237) is a huge hydrogen II region, located at the end of a huge molecular cloud in the constellation Unicorn. The cluster and nebula are about 5,200 light-years away from the Earth and about 130 light-years in diameter. The mass of this nebula is estimated to be about 10000 times that of the sun. Type emission nebula right ascension 06h 33m 45s[ 1] declination? 04 59' 54÷[ 1] Distance 5,200 ly (1600 pc)[2] Apparent magnitude (V) +9.0 apparent diameter (V) 1.3 Arc-divided constellation unicorn Physical properties: absolute magnitude with radius of 65 ly. There is an open cluster numbered NGC 2244 in the center of the nebula, and the star wind from the star cluster has blown a big hole in the center of the nebula. These stars were formed by the clouds around them about 4 million years ago, and there is an isolation layer of dust and hot clouds on the edge of the hole. The ultraviolet radiation emitted by this hot star breaks down the surrounding clouds and makes them glow. The rich hydrogen in the nebula is excited by young and bright stars, which makes NGC 2237 appear red in most photos. The most special thing about this picture is that its color is different from the common rose nebula photo. Through the filters of red light emitted by hydrogen, green light emitted by oxygen and blue light emitted by sulfur, astronomers took photos of the Rose Nebula, and then combined them to synthesize the beautiful image above. In the image, we can also clearly see the dark filamentous dust bands scattered in the clouds. Recently, astronomers have discovered some fast-moving molecular clusters in the Rose Nebula, but their origins are still unknown. The Rose Nebula is located in the unicorn constellation in the southern sky. Its size is about 100 light years, and it is about 5000 light years away from us. You can see it with a small telescope. (NGC 2237) is a huge hydrogen II region located at the end of a huge molecular cloud in the constellation Unicorn. This molecular cloud includes five NGC objects: NGC 2237, NGC 2238, NGC 2239, NGC 2244 and NGC 2246. The open cluster NGC 2244 is closely related to the Rose Nebula, and the stars in NGC 2244 are formed by the matter of the Rose Nebula. The cluster and nebula are about 5,200 light-years away from the Earth and about 130 light-years in diameter. The mass of this nebula is estimated to be about 10000 times that of the sun. The Rose Nebula in NGC 2244 is not all red, but it is still very beautiful. In the sky map, the beautiful rose nebula and other star-forming areas are always dominated by red-partly because the emission dominated by the rose nebula in the nebula is produced by hydrogen atoms. The strong visible light of hydrogen atom -H-alpha is a red band in the spectrum, but a beautiful emission nebula needs more than red light. Other atoms in the nebula are also excited by high-energy starlight, and also form narrow-wave emission light. In this gorgeous image of the central region of the Rose Nebula, the narrow-wave image consists of red light emitted by sulfur atoms, blue light emitted by hydrogen atoms and green light emitted by oxygen atoms. In fact, the method of using these narrow-wave atoms to express colors has also been used in Hubble images of many star nurseries. This image spans about 50 light-years in the constellation Unicorn and is located in the Rose Nebula, with an estimated distance of 3,000 light-years. It is generally believed that after the formation of stars, the pressure generated by the stellar winds of O-type and B-type stars compresses interstellar clouds. The observation of Chandra X-ray Observatory in 200 1 year confirmed that there are very hot young stars in the center of the Rose Nebula. The rich hydrogen in the nebula is excited by young and bright stars, which makes NGC 2237 appear red in most photos. Through the filters of red light emitted by hydrogen, green light emitted by oxygen and blue light emitted by sulfur, astronomers took photos of the Rose Nebula and then combined them to synthesize these beautiful images. In the image, we can also clearly see the dark filamentous dust bands scattered in the clouds. Recently, astronomers have discovered some fast-moving molecular clusters in the Rose Nebula, but their origins are still unknown.