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
