Massive stars and low-mass stars live different lives. They are born in different environments, fuse different elements during the course of their lives, release different amounts of radiation across the electromagnetic spectrum, die in different ways, and enrich interstellar space with different metals. We see stars at all stages of life in the galaxy, and their study allows us to piece together how stars form, and how the rarest ones are different. The image above shows two distinct clouds, both about 5,000 light years away in the constellation Cygnus, along the Galactic plane. The smaller bubble on the left, literally...
We call it dark matter because it doesn’t give off light, right? Well there is a lot of matter than doesn’t radiate, but the difference is that whatever the stuff is that we call dark matter doesn’t interact with anything through the small-scale fundamental forces. The only way we have been able to detect it’s presence is through large-scale gravitational interaction. Dark matter is ‘dark’ because it doesn’t interact with anything in a way that lets us figure out what it’s made of. Well now that we’ve got that out of the way, we can look at the new...
This Galaxy, NGC 7714, has an odd shape. In fact we call it a ‘Peculiar Galaxy.’ Why doesn’t it have the characteristic spiral arms if it is indeed a spiral? Why doesn’t it look more diffuse and football shaped like an elliptical galaxy? The reason is that like millions of other galaxies in the Universe, it has recently collided with a nearby companion galaxy. Now using the term ‘collided’ is not really accurate. In reality the two galaxies are interacting via gravity. During a ‘collision,’ stars in the interacting galaxies don’t physically hit each other. The galaxies are incredibly large,...