Occult Activity Tonight!
Oh yes. Occult. Exciting right? Those of us in LA and some other areas (apparently points in Nevada, Idaho, and Western Montana, and the cities of Calgary and Edmonton) will see have the chance to see something quite remarkable if we stay up until 03:34 Pacific time. I learned this from Phil’s blog. You can find out more from Sky and Telescope (that’s their figure on the right). The event is this. If you stare at the star ζ (Zeta) Ophiuchi, which is visible to the naked eye, it will go dim for about eight seconds. Why, because an asteroid (824 Anastasia) will pass directly in front of it. You can’t see the asteroid directly, since it is too small and too dim, but nevertheless its presence between you and the distant star will be enough to make it go dim for a bit. Isn’t that wonderful? Have a go!
This remarkable effect (called occultation – hence the sneaky blog post title: the key root meaning here is “hidden”), while it might seem rather mundane in some ways (although you’re seeing the effect of an asteroid with your own eyes!) is extremely powerful in astronomy. It is a great way, for example, of detecting planets orbiting other stars! You’re familiar with occultations already actually. When the moon moves […] Click to continue reading this post