Alliteration is accessible to all! Okay I’m done. Start some science! Really done this time. Today’s double post covers the smallest of stars, still larger than most planets, and the only weather Mercury will ever have. Humans are naturally interested in the extremes, the biggest, smallest, fastest, hottest, coldest, and every other characteristic outlier. With stars, being so huge and powerful, we are often more interested in the largest, hottest, and most energetic. Though on the opposite end of the spectrum, Cambridge University astronomers have discovered the smallest star in the known universe. The star, a red dwarf, has the...
How did supermassive black holes form in the early epochs of the universe? More importantly, how did they have enough time to grow as large as they did? The answer requires a very different universe. And back then, conditions were much different than they are now. There was a lot of gas, little dust, no stars, and a plethora of dark matter. Astronomers have spent decades observing early quasars, massive active galaxies powered by huge black holes feeding on surrounding gas. But these galaxies are seen so early in the universe’s history, one starts to wonder how a black hole finds sufficient...
Black holes form when a massive star runs out of fuel. Gravity causes the core to collapse down to an object so dense that light itself can not escape. In the Milky Way galaxy, there are expected to be over 100 Million black holes, though of course we can’t see them. The one we can see is the supermassive black hole Sag A*, lying deep within the core of the galaxy. But how did Sag A* form? Was it from the merger of many smaller black holes? Or is there some other process forming the most enigmatic objects in the...
The gravitational center of most objects and clusters in the universe are the place where the most massive and high energy interactions take place. For the solar system, the Sun’s core is hot and energetic. For star clusters, central regions host the most massive and brightest stars. For galaxy clusters, the most massive galaxies in the universe are seen in the center. And for individual galaxies, the Milky Way included, the core is where the fun happens. In the core of our galaxy, there are many massive and powerful objects, not limited to a supermassive star cluster, pulsars, supernova remnants,...
On the York Universe radio show this past Monday evening on astronomy.fm, I was having a discussion with another host about how so many things in Astronomy can take Millions or even Billions of years, yet there are still all kinds of phenomena that happen in seconds, hours, weeks, years, or on the scale of human lifetimes. Stars live for hundreds of Millions of years at the low end, yet the intense brightening from the Supernova death of a massive star lasts for only a few days or weeks. It’s as if the Universe is piquing our interest with short...
