Friday, April 20, 2018

Be Cool, Star


Unfortunately, I only have 1 reference article for this week’s blog, and it was listed as ‘Opinion’. So, if you don’t already, take this week’s blog with 2-3 grains of salt. I did try to follow the link to the original article in the Astronomical Journal, but I’m not subscribed to it, so couldn’t get past their first page. From the looks of some of the titles listed for their current issue, their articles are seriously geeky, which is why I sometimes have to rely on someone else to explain it to me. Having said all that, hand me an ice cube for my drink, and let’s get started.
NASA’s Spitzer space telescope (launched in 2003) has found 14 of the coldest stars known, but it’s expected that far more are waiting to be discovered. These 14 objects are hundreds of light-years away and are thought to have temperatures 350 to 620 degrees Fahrenheit. That’s bitterly cold for stars.
These are ‘failed stars’, also known as brown dwarfs, which have been known to exist for years. Spitzer and its sister, WISE, could recognize them by the hundreds before too long. Spitzer was assigned specific patches of space to study, but WISE has been tasked with studying the entire sky. WISE’s task is 40 times the size of Spitzer’s.
Brown dwarfs form like any other star, out of collapsing balls of gas and dust. But they are puny things, and never collect enough mass to ignite nuclear fusion and start shining. The smallest known so far are 5 to 10 times the mass of Jupiter, and there are giant gas planets of that mass around other stars. Without nuclear fusion, what little internal heat these bodies started with eventually faded away.
It’s possible that WISE could find an object about Neptune-sized (or bigger) in the far reaches of our solar system. Raise your hand if you’ve heard the story of Planet X, a large planet so far out we can’t see it, but it has some disruptive tendencies for the orbits of the outer planets, dwarf planets and other objects we know of. Some scientists speculate it might even be a brown dwarf companion to our sun.
So are these 14 examples of planets or stars? Well, they’re hot for one, and unbelievably cold for the other. I assume someone will decide what they are, eventually.

www.networkworld.com/article/2231137/nasa-finds-14-new--seriously-chilled-stars.html