On Saturday night, the moon will occult (cover) some of the bright stars in the Pleiades, a star cluster also known as the Seven Sisters. This event will be visible from Rochester, starting at sundown. If we aren't clouded out, I predict that women will faint, babies will cry inconsolably, grown men will wail and gnash their teeth, animals will run wild in the streets, and some will be forced to question our very place in the uniiverse.
Well, not really. Though this may seem like no big deal, it is actually quite rare that the Moon occults a bright star, and tomorrow night at least four stars that are going to be occulted, which is rarer still. If you're interested in natural phenomena, then you might want to see at least one of these in your lifetime.
That's not to say that an occultation is like a rock-and-roll show, or even an episode of Wife Swappers. Basically what you'll be doing is watching the Moon slowly travel through a group of stars, and every so often one will just "wink" out of sight. This is the type of event where you sit in a lawn chair with a beer in hand and chill out while watching the show.
To the bare eye, the Pleiades is a bright smudge containing a few stars. To really get a good view of the occultation, you can use a pair of binoculars to watch as each star is covered. Looking at the Moon in binoculars is also worth doing at least once, so you can spend some time doing that while you're waiting for the rest of the show.
The four bright stars that will be occulted in Rochester are:
- Electra at 6:37. Since the sun sets at 6:36, it will probably be too bright to see this.
- Merope at 7:14. Twilight will have just ended, so it will still be pretty bright.
- Alcyone at 7:47. Based on the current forecast, this is probably when you'll decide that the clouds will never clear, and you'll begin cursing me for even mentioning this.
- Atlas at 8:34.
Each of the stars will be covered for roughly one hour. Since the leading edge of the moon is dark, and the trailing edge is light, it will be difficult to see the stars re-emerge without a telescope.
If you're interested, there's an article about the event at Sky and Telescope. If you're really interested, you can get maps and times for each event at the IOTA site. If you're wondering where the heck the Pleiades are located, you can find it on a star map at the Skymaps site. If you want to go totally nuts, you can get in your car and travel to a site where there's a grazing occultation -- this means that the star will wink multiple times as it is covered by the mountains on the dark edge of the Moon.
