Strangers in the sky

What the hell did I just see?

I was outside tonight, stargazing. The humidity has dropped enough to make it easier to see more stars, and I didn't have to worry about my lenses fogging up. But I had gone outside late - about 11:00 - and the stars had rotated significantly since my first steps back into stargazing two weeks ago. The Messier Objects I had noted earlier were now in new positions, and Sagittarius itself was farther to the southwest, in a new region of skyglow - possibly from a new gas station along route 309 heading into Hazleton.

I had seen quite a bit and was a little disappointed with the lack of satellites. Not that satellites were the main reason I was outside, but I always find them an interesting diversion. I had seen a few, but not as many as I had in previous sessions.

I was getting myself ready to get up and head back into the house when I cast my eyes to the northwest, towards (I believe) Serpens Caput. There I saw an interesting triangular asterism I hadn't noticed before. I must be getting tired, I thought. I could swear that triangle is changing shape.

It was.

I slapped my binoculars to my eyes and looked. At first it was hard to tell what was happening - it was like looking at two clouds in the sky, one in front of the other, and you can't tell if the one in front is moving to the left, or the one in back is moving to the right. There are no good fixed reference points in the sky when you're dealing with multiple moving objects.

Two of the three stars in the triangle were moving, together.

I've seen things like this before. Usually it's the International Space Station and a space shuttle right after they un-dock - really quite a sight, all too rare these days; I once had our entire night-shift crew out in the parking lot of our old building to see this, and Security dropped by to investigate. I once saw...something else. I think it was a satellite cluster called Snowflake, an experiment in coordinated satellite guidance, but I don't know.

This looked like one satellite chasing another across the sky from Northwest to South. Both were approximately the same magnitude, both fit into the same binocular field, and both vanished at about the same point in space - suggesting that they were actually at the same altitude and both passed into shadow at the same place. It was very strange having the leading satellite vanish from my direct vision but still be visible in my averted vision for a few seconds while I tracked the trailing satellite until it, too, passed into shadow.

I packed it in right away. Got myself inside and checked the atomic clock on the wall: 11:27 PM, Friday, August 4th, 2006. No more than two minutes had passed since I watched the twin satellites vanish from view.

This will be easy, I thought. I fired up my cranky old PC and, with some cajoling, got Heavens-Above (www.heavens-above.com) on the screen. Now it was just a matter of determining which two satellites passed into shadow above Nanticoke, PA at about 11:25 PM.

None.

The closest thing I could find was a Cosmos 2237 Rocket. It had the right path, but not the right time - it should have passed into shadow at 11:16 PM. And, most importantly, there was only one of it. Not two. No other satellites came close to taking that same path across the sky.

So what the hell did I see? Could the Cosmos 2237 Rocket have had a collision that broke it into two pieces and slowed it down enough to be ten minutes behind schedule? I have no idea. I can check for future appearances and see if one satellite appears as two.

It's good to know that the sky is still full of surprises, even for someone who thought he knew his way around it!