Ufo in SF tonight?

I may have just had my very first, and wholly unremarkable, ufo sighting.
I live in the Mission District in San Francisco, and just got off of work. I was walking the dog on a very busy street when I noticed a light moving across the sky. Not so unusual considering my close proximity to two Intl airports, but what caught my eye is that it looked like a very bright star, with no blinking lights.
I tracked the object until it went behind my row of buildings (it was really high up) and raced up to my back porch. I caught sight of it again and watched as it reached a certain point in the sky and just vanished. As I was wondering about the oddity, another exactly similar light, seemingly following the same trajectory did the exact same thing and vanished at the same point in the sky (I could tell because it happened with both objects close to one of the few visible stars).
Not very heart-thudding or revelatory, but that's what I saw tonight.
If anyone else in the area has seen anything similar, I'd appreciate knowing.
Thanks.

So what makes you think that these "lights" weren't airplanes other than they didn't have blinking lights? Can you elaborate on "they disappeared?" How did they move? Slowly and in a straight line like conventional aircraft? Or did they move like our airplanes cannot?

What you just saw is most likely the International Space Station and the shuttle Atlantis as they were passing over California .. that's exactly how I saw it for the last two days .....

Hmmm well here in San Francisco, with all the fog and low level clouds, it's pretty hard to see stars, let alone international space stations or satellites. There all the light radiation from the city that also makes it near impossible to see anything but the moon, perhaps a few bright planets and stars... if the sky was clear.

I'm guessing what was seen was probably a spot light for some even happening in the city, or... airplanes from SFO, there aren't too many more options other than it being an Alien Space Craft... but if it look like a vehicle, and it was flying, and it could not be identified then that's what I would consider to be a UFO.

There aren't many explanations other than it being alien spacecraft? What about all the top-secret aircrafts that our military is probably flying around?

If you ask the average American what the most "high-tech" aircraft is that our military has, they would most likely say the B-2 Stealth Bomber. The B-2 Stealth Bomber took it's maiden (first) flight way back in 1989. It is currently 2007. Just try to imagine what "we" are working on nowadays..............

I would tend to favor the space station/Atlantis explanation.
The fog hadn't rolled in when I posted last night, so the sky was clear.
Both lights seemed to follow exactly the same trajectory, as I mentioned in my post. Their movement was very smooth and they were about 20 or so seconds apart (from when I saw the first "dissapear" to when I saw the second come into my line of view.
They looked exactly like Venus (as seen w/ the naked eye) but not quite so large (much brighter than any of the other stars in the sky).
Definitely not a spot light, as I live on Valencia and 16th, near the ballpark, I know the difference.
The last time I remember looking out of my window for more than a second or so without seeing airplanes/helicopters was on 9/11, so I see them all the time, and I've never seen lights like these before.
The fact that both lights seemed to fade (I say fade, but it wasn't a slow thing, not quite a blink either, difficult to explain) at exactly the same place in the sky was to me the strangest part, and did bring up images in my mind of something that was reflecting light and suddenly moved into shadow (much as a orbiting craft would do I guess). They were just so bright - which made me thing they were closer to Earth than the space station, but who knows...

I saw the same thing last night - here in PA. Very bright ISS and Shuttle. That was 2 passes prior to their pass over California. My first ISS sighting and great to see the shuttle 20-30 seconds behind. I knew they were arriving and went out to see them (based on the NASA tracking web site).