It’s time to look at pictures of stars. No, we’re not talking about Hollywood celebrities here, but giant balls of blazing plasma.
Let’s start with the closest and most familiar star, the Sun. This photograph of a “star” was captured by NASA’s SOHO spacecraft in the infrared spectrum. This is the highest energy light that’s pouring off the Sun, normally invisible to our eyes.
Betelgeuse. Image credit: Hubble
This is a star photograph of Betelgeuse, the famous red giant in the constellation of Orion. Betelgeuse has about 20 times the mass of the Sun, and it has bloated out to the point that it’s about 1000 times the radius of the Sun. Imagine a huge red star so large that it engulfs the orbits of Mars and Jupiter! This star picture was captured by the Hubble Space Telescope.
This looks like a photograph of a beautiful nebula, and it is, but right in the middle of the nebula is the star Eta Carinae. Thought to have 150 times the mass of the Sun, Eta Carinae is giving off 4 million times the energy of the Sun. Astronomers think this star has only been alive for 3 million years, and expect it’s going to explode as a supernova in the next 100,000 years or so.
Sirius. Image credit: Hubble
This is a picture of the star Sirius, also known as the Dog Star. Sirius is the brightest star in the sky, and a familiar sight to astronomers. But did you know that Sirius is actually a double star? If you look carefully, you’ll see the dim companion star almost lost in the glow of the much larger, brighter Sirius A.
The Pleiades, Anglo-Australian Observatory/Royal Observatory
Here’s a photo of one of the most famous collections of stars, the Pleiades star cluster. The stars in this cluster are fairly young, less than 100 million years old. With the unaided eye, you can see 14 of the stars in the cluster, but it’s estimated that there are a total of 800 solar masses in the entire cluster.