What If the Earth Had Rings?

Very cool simulation! If the frame is cut off, you may want to click on the video and view it directly in YouTube.



(Hat tip: Michael D.)

Time-Lapse of Leonid Meteor Shower 2009

Video by Dave Kodama, Orange County Astronomers.

Given that this video was taken from very dark skies, it is evident what I meant earlier when I said that the term "shower" is a bit of a misnomer. Definitely note that the streaks which can be seen early in the video are from airplanes. Meteors are visible later in the evening after the constellation Leo begins to rise, about halfway through the video.

Go Watch the Meteors... Maybe

If you've heard the hype about this year's Leonid meteor shower (the Leonids are the annual shower that occurs in November), you might wonder why I've been reluctant to add my voice to the chorus imploring you to go watch it.

That's because meteor showers are total crapshoots. It's definitely not a terrible idea to set your alarm and spend at least a few minutes during the wee hours Tuesday morning, but with some caveats in mind:

First of all, if you haven't ever seen a meteor (or "shooting star"), there are almost zero qualifications to heed. You absolutely owe it to yourself to see one at some point, so consider going outside early Tuesday morning, provided it's clear, and keep your eyes on the sky for 10 minutes or so. You'll see at least one. Especially if you go somewhere fairly dark, i.e. somewhere where you can at least see some of the constellations.

But...

For all but a very few meteor events, I think the term "shower" is a bit of a drunk metaphor. On any given night, there are always meteors; the average is about 2 per hour, or so I've heard. This is because there are just that many random rocks (albeit very small: most meteors that we observe are only sand-grained sized, if you can believe it!) floating around the vicinity of Earth's orbit.

A so-called meteor 'shower' occurs when the Earth passes through an entire debris field of small bits of rock left by comets which have passed nearby in recent years. It may surprise you to learn that these events happen about once every month or so, and this is when the number per hour greatly increases: anywhere from 20 to 50 to 100, or, in this year's most optimistic estimate for November's shower, possibly as many as 300 per hour. Mind you that would mean seeing a shooting star about once every 12 seconds, rather than once every 30 minutes.

(I recommend the following articles for further information: Will the Leonids Roar Again? and The 2009 Leonids Are Coming!)

If that turns out being the case, it may be a really neat thing to watch. Definitely beats having to spend an entire hour outside to see one or two!

But something tells me that if when you go to bathe tomorrow morning, your water were to release a drop from the spigot once every 12 seconds, you wouldn't call that a "shower". So keep your expectations realistic!

This event, in 1833, in my judgment would have been more properly called a shower: