Wednesday, January 16, 2008

Janus and Epimetheus

I used to be scared that the universe was a genuinely random place. Scared there was no destiny, no design, no wheels within wheels.

Fuck that.

In the last 10 years or so I’ve come to not only accept randomness but embrace it. Which is part of my fascination with orbital mechanics (the overarching theme of this blog), the complex structures and counter-intuitive oddities created by the accumulation of countless collisions and near misses. By chucks of rock hitting the sweet spot of a gravity well at just the right angle and speed.

For instance, there's these guys:



This is a picture of Janus and Epimetheus, two moons orbiting Saturn just outside the F ring. Their orbits are very close, about 30 miles apart. And every 4 years or so, when they line up just right, they switch orbits, narrowly avoiding a collision in the process. 4 more years, they switch back. The orbits are actually pretty stable.

As much as anything is stable out there.

More on that later.

4 comments:

Maggie said...

It sounds like a dance, the two waltzing around each other as they circle Saturn.

Nancy Dancehall said...

Love it. How close is 'narrow?'

Full dancecard is right. First week of school and I've already written a 7-page lab report, three pages of homework, and I have a test next week.

Clowncar said...

Don't now, but since the orbits are 30 miles apart, pretty freakin close.

Wow, that's alotta work. Must be like being back in GK (my second Drake reference today!). Except with tiny children underfoot. As opposd to, say, large drunken freshman children.

Nancy Dancehall said...

Yeah, it was much more fun when I was one of the drunken freshman children.