Winter sky
- squareinfinity3000
- 10 sty
- 3 minut(y) czytania
Winter is the season with the longest nights! That's why it's the perfect time for amateur astronomers because you can both get a good night's sleep and admire a star-studded night sky. But the problem lies in the purity of the sky. Unfortunately, there are relatively few clear nights during the winter season. But what can we see when we look up?
Blue star cluster - Pleiades
Due to their brightness of 1.4 mag, they are visible even with the naked eye! (The average person notices objects up to 6 mag.) Also known as Messier 45, they are young stars and very hot. That is why they glow blue – the Blue Giants. This color is also reflected by a nearby gas cloud. But the blue encirclement around the Pleiades is not the associated nebula from which the stars formed. It's due to the Pleiades nebula, which is an independent cloud drifting through the cluster at a relative speed of about 11 km/s. Perhaps it is because of their brightness that they have fascinated mankind for so long. In the Lascaux caves, they are depicted as an image of a bull over which there is six points above. The bull represents the constellation of Taurus, and the points represent the brightest stars in the Pleiades – the Seven Sisters. The names of the stars come from mythology – the daughters of Atlas. They are Alcyone, Merope, Electra, Celaeno, Taygeta, Maia, and Sterope II (or Asterope).
Messier 42
Messier 42, better known as the Orion Nebula, can be seen with the naked eye from a dark-sky site. But to be honest, I haven't seen it 😉. It looks spectacular even with a small telescope like mine. This nebula is the closest large star-forming region to Earth. It's big and bright (4 mag) and full of color. Probably that's why it looks so beautiful.
NGC 2244 and NGC 2237
NGC 2244 is an open cluster in the constellation Monoceros. It lies in the center of the Rosette Nebula (the brown ring in the image). The Rosette Nebula is sometimes called the Skull Nebula because of its appearance (but it's difficult to see a skull in my image, so I stick with the Rosette Nebula). They are 5000 ly from Earth and have a radius of 65 ly. The light from young stars in the cluster excites the atoms in the nebula, causing them to emit radiation. This process creates the glowing emission nebula we observe. However, it's important to note that visible light images reveal only a fraction of the nebula's details. Comparing these images with those captured in other wavelengths, such as radio, provides a more complete understanding of its structure and composition.
Christmas Tree Cluster
The cluster with the perfect winter name - the Christmas Tree Cluster! It is also located in the constellation of Monoceros. This cluster is immersed in a reflection nebula where new stars are forming, surrounded by a larger red-glowing emission nebula. The outer part is mixed with dark clouds of interstellar dust. This is why it looks like a Christmas tree. But this is the H II region, so it looks much better in X-rays than in visible light. Even an observed bright spot in the night sky looks better if you know what it might look like. And it could look stunning! (NASA)
Komentar