CAC's Spaced-Out Challenge: Now You See It, Now You Don't

Late Night Edition, my apologies for not getting this up earlier. For those living on the East Coast, our target this week is easy to spot, riding halfway between the Eastern horizon and zenith right about now.

As Spring yields to Summer, the sky continues to change in the evening. For those of you lucky enough to live in rural regions, the grandeur of our home galaxy comes into full view. For the rest of us, we can enjoy a richer field of objects with binoculars and backyard scopes. One of the more interesting this week can be "unseen" just by staring at it. We call it the "Blinking Planetary."

Planetary nebulae are nothing new for the Spaced Out Challenge, as we've already hunted down the Ring Nebula in Lyra in an earlier edition. Close by, however, is a more elusive and fun version. From Guy Consolmagno's Turn Left At Orion:

The Blinking Planetary puts out as much light as a ninth-magnitude star but this light is spread out over a small disk rather than concentrated at a point. Thus, the nebula shows clearly with averted vision, but as soon as you try to stare directly at it, it may disappear entirely. (When you stare straight at the nebula, the central part of your vision, which is more sensitive to detail than to dim light, picks up only the pinpoint central star, not the cloud surrounding it.)

The Blinking Planetary is also on the light pollution-friendly FULP List, with its small size combined with it's concentrated brightness making it a target from even downtown areas. Here's how to find it.

As always, check out Ace's store for your amateur astro needs, clear skies to you and keep looking up!

posted by CAC at 01:31 AM

| Access Comments