You probably saw all the hoo-rah last week about a COW-like object in space that has astronomers “mystified”, or “baffled”, or even “stumped” (according to the breathless headlines on various news sites. So, what’s behind the headlines that are milking the story for all its worth?
Making a COW
Let’s start with the name of this thing that astronomers observed. The full name of the object is AT2018cow, and you can see the discovery image here. It erupted in or near a galaxy known as CGCG 137-068. That’s located about 200 million light-years away in the constellation Hercules. This shows the location of the “Cow” in the distant galaxy.
Think of it as some kind of eruption in a star, not unlike a supernova or other such outburst. These happen fairly frequently. Astronomers give them complicated names based on what instrument is used to observe them. The name also includes WHEN they’re found. This one was found by the Asteroid Terrestrial-impact Last Alert survey telescope in Hawaii. That’s where the letters AT come from. 2018 is the year it was discovered, and each time there’s one found, it is followed by a letter or sequence of letters. In this case, ...