Nasty Star

I had to smile when I saw this. Astronomers called an unusual Milky Way star Nasty. The name comes from its official name (that which is entered in as star catalog) NsST1. The unofficial name is Nasty1.

Nasty1 was discovered with the Hubble telescope and it's a Wolf-Rayet star.

What's a Wolf-Rayet star, you say?

Well, it's a massive star that has lost its outer hydrogen and is fusing helium or heavier elements in its core. They are typically very luminous, many thousands of times the brightness of our sun. They also have unusual spectra that indicate highly ionized helium and nitrogen, or in some cases carbon. They also show spectral lines that indicate heavy elements in their surface layers.

The name Wolf-Rayet comes from the two astronomers that first discovered them, namely Charles Wolf and Georges Rayet. They worked at the Paris Observatory in the late 19th century.

There are many classifications of Wolf-Rayet stars, but we won't go into that, except to say that the classification is based on variations in the star's spectra.

How are Wolf-Rayet stars formed? That's a good question. At one time, astronomers thought it was caused by the intense stellar winds that such stars exhibit. Now, they believe it's because of binary interaction. This means that a close neighboring star decides to feed on its big cousin. In other words the big cousin star falls victim to gravitational stripping. I would call this a stellar heist. It's when a nearby star steals the hydrogen from a large star and this feasting will continue until the parasitic star completely consumes the large star's hydrogen thereby converting its victim to a Wolf-Rayet star.

It turns out that this Wolf-Rayet star formation is very rare, and the Nasty1 star discovery gives astronomers the opportunity to examine this unusual formation process. Normally, astronomers see twin lobes of gas around a Wolf-Rayet star, but in Nasty1's case, they saw a 2 trillion mile disc of gas orbiting the star. This was the proof that indicated a stellar cannibalism was taking place.

My take on this is that it's another case of where an accepted theory is put into question and then changed to fit the new observational data. That's the way science is supposed to work.

Thanks for reading.