This weekend Angela and I went camping in Killbear Provincial Park. Normally I would post a photo from that trip, but I wanted to post this one first.

While browsing the web on Friday, I noticed that the International Space Station would be flying almost directly over Waterloo early in the evening. So I invited Angela out with me to go "space station spotting". The station was supposed to come into view just after 9:38pm, fly overhead, and disappear at around 9:42pm, so we had a four minute window.

Sure enough, at 9:39pm we spotted it, and followed it as it flew over. It really moves fast! 7.7 kilometers per second looks really fast even when you are over 390 km away.

Of course, I had to get a photo of this spectacular event. I tried to get my camera focussed as accurately as possible by taking some test shots of the moon, and I tried to get the exposure right by using the "Sunny 16" rule. Even with that preparation, it is really hard to get a good picture of something the size of a house at a distance of 390 km, especially when you don't have time to accurately check your exposure.

Anyway, I should explain the picture. I was hoping that the ISS would fly close to the moon so that I could get a really dramatic shot, but luck was not with me. Instead, I took one of my test photographs of the moon that I took right before the ISS flew overhead and pasted it into the photo for dramatic effect.

Both pictures are pixel-for-pixel crops (sometimes called "100% crops")... so neither of them were resized. That is how big the ISS would actually appear to be if it was beside the moon. The moon is much further away, of course. ;)

Incidentally, if you want to see when interesting objects are flying over your city, you can use this handy website: Heavens-Above. Just specify your location by GPS coordinates or by selecting a city from their database, and then click the ISS, shuttle, or other satellite links to see what will be flying overhead in the next few days.

Technical details: This is a composite of two images shot within minutes of each other with my Rebel XT + 70-300mm IS at 300mm. The moon was shot at ISO 400, f/11 for 1/400th of a second, and the ISS was shot at ISO 1600, f/5.6 for 1/400th of a second.

Comments

Very cool!  That website is really handy too, I may have to go out into the
backyard with the binoculars sometime.