Meanwhile, I was reading about Sedna the other day and it kept me up all night. You see the basic structure of our solar system is the Sun (that's the big yellow one), some planets, (and their satellites) an asteroid belt, some more planets (and their satellites), some dwarf planets and something called the Oort cloud. A hypothetical ring of Killer Comets that lies around one quarter of the way between our Sun and the next nearest star, Proxima Centauri.
Sedna is one of those dwarf planets I mentioned. Or a candidate for a dwarf planet...I'll get into that in a moment. Pluto was recently downgraded from a planet to a dwarf planet, for comparison. That's a harsh look in the mirror in the morning, isn't it? Sedna is a something called a trans-Neptunian object. Really anything beyond the orbit of Neptune is classified as a trans-Neptunian object. But Sedna is one of the larger and more distant objects to be classified thusly.
Roughly half the size of Pluto (using my oh-so-scientific comparison of the two dwarf planets on this chart), it has a wildly elliptical orbit around the Sun. Right now it is about 3 times as far away from the Sun as Neptune or around 88 astronomical units (or AU. One AU is roughly the distance between the Sun and the Earth). At its aphelion, or furthest point in its orbit from the Sun, it is an astounding 975 AU. Or as I like to say, really fucking far. That's why it's only a candidate for a dwarf planet. Because it's so fucking far away we can't be absolutely sure yet.
It's so far away that when it reaches this distant orbit in a few thousand years it may actually affect the path of those Killer Comets in the Oort cloud that I was talking about earlier. It might not actually reach the Oort cloud, but its gravity might affect the orbits of one or more of those Killer Comets. Maybe even sending one or two of them our way! We need to prepare the rockets and the drills and Bruce Willis!!!!
Sorry...went off on a little tangent there. But wait...it gets worse.
While reading about Sedna, I ran into something called Nemesis and my mind was further blown. You see, you think that our solar system only has one star, right? Well, my insignificant motes on a planetary pinhead, that may not be true.
Some astronomers actually believe that we are a binary system and that a brown dwarf star named Nemesis is out there, 50,000 to 100,000 AU away. Somewhere beyond the Oort cloud. So dim that none of our current instrumentation can pick it up. Oh sure, we have a plan to figure out if all this is true or not. But it might not matter. Because the aptly-named Nemesis wants to kill us all.
That's right. It wants your soul.
The idea behind the hypothetical Nemesis is a cycle of planet-killing destruction that seems to occur around ever 26 million years on our wee little planet. A bunch of scientists sat around a campfire and came up with the scariest fireside urban story ever! A star, a DEATH STAR, that has a wildly elliptical orbit around the Sun. Kind of like Sedna, but scarier. And because of its wacky orbit, it may actually go crashing through the Oort Cloud every 26 million years. And that's when those pesky Killer Comets come into play. Nemesis whacks them out of their normal orbit like a cosmic game of curling and sends them screaming towards us.
To kill us.
I'm having a bit of trouble wrapping my tiny brain around this. I can't fathom that we can detect a dwarf planet that is half the size of Pluto that by all accounts is really fucking far away, but that we might actually have another freakin' star in our solar system! That's like having a small, angry man living behind the hedges in your backyard. And every once in a while he starts throwing shit at your patio. You'd think we would know about stuff like this.
So sleep tight and try not to think of the Killer Comets or the dwarf planets or the brown dwarf stars that are out there trying to kill us all. You should really just try not thinking about any killer dwarfs at all. Especially ones that might live behind the hedges in your backyard. You wouldn't want to anger him.
Note: Remember to play the Bug-Eyed Trivia Challenge every day. Can you imagine that I have a longer post about Space that is still to come?