It's a blinking Vesta!

One of the task for the Prime Timers this month is to observe the bright asteroid Vesta as it approaches Jupiter. It's not that easy, for it's in a rich star field. As one person searched for it last night, we remarked about how incredible it must have been to discover an asteroid. However, the truth is, with the arrival of photography and the invention of the "Blink Comparator," it's a piece of cake.

The blink comparator allows you to take two photographs of the exact same star field taken on different nights and compare them. If something changes while nearly everything else stays the same, the changed object jumps right out at you. That's the way our eyes and brain work. I decided to simulate such a device by taking two screen shots from Starry Nights software. One shows the star field that contained Vesta last night - Jupiter is the bright object to the left. The other shows the same star field, but with Vesta missing. When you combine these into an animated GIF so one is dislayed right after the ther and they continue to alternate - well - it won't take you long to see why they called it a "blink" comparator - or maybe they should have called it a wink comparator ;-) See for yourself how easy it is to spot Vesta.