While you're shopping, eating, napping, or having to work this holiday season, cast your eyes upward over the next few weeks and you might catch sight of a bonafide deep space dweller. It's Comet C/2012 S1, better know as ISON. You won't get another chance to see this visitor, if ISON survives a close pass by the sun on Thanksgiving Day, it'll streak by earth close enough to see with the naked eye or a small pair of binoculars, on its way to the stars:
Some comets are on long, elliptical orbits dropping them in to the inner solar system before sailing them back out to the depths of space. There, they slow, stop, then fall once again back into the warmth and light. Comet Halley, for example, is on a 75-year orbit that takes it out past Neptune.
But some are more extreme. If they get an extra kick on their way in — perhaps from a collision, or a boost by a planet’s gravity — their elliptical orbit gets turned into an open-ended hyperbola: they have more than enough energy to leave the solar system forever. Once they’re gone, they’re gone.
At its peak velocity during its closest dip to the fiery sun's surface, ISON or its remains will be traveling at a sizzling 225 miles per
second.
That's 0.1% of c, where
c denotes the speed of light, for you physics fans and wonder junkies.
- While you're enjoying family this week, keep in mind there's one branch of the human family we know very little about, even though we still carry parts of their genetic heritage. This mysterious clade is known only by a few fragments of bone and DNA, and we call them the Denisovans.
- A fearsome looking new dino that could give T-rex a run for her money, never before seen by science, has been unveiled.
- Was ocean water similar or different a 150 million years ago than it is today? Thanks to another ancient visitor, we'll soon find out.
- Gaius Publius connects many ancient dots to modern day climate change in a single, remarkable post.
- My friend and front-page colleague MeteorBlades inadvertently joined the myocardial infarction and cardiac stent club this week. We're all glad he survived the initiation ceremony with flying colors, and especially grateful he, like millions more Americans, had comprehensive health insurance that made his treatment and recovery possible. A socialized medicine program called Medicare.
