As summer draws to a close for much of the northern hemisphere, try to get outside for some (hopefully) clear skies and a little star gazing.

We've taken a good look at many of the star gazing apps available for the Mac and the iPhone, and I thought it would be fun to try the 'next step', an iPhone app that finds passing satellites and the International Space Station. There are a lot of websites that give you this information, but having it in an app is even nicer.

I've just tried Satellite Visibility [iTunes link], a US$2.99 app that does the job and worked for me the first time out. You tell the app where you are, or let the phone GPS determine your location. You then get a list of all the brighter manmade objects hurtling around the earth that you can see over the next couple days.

If you click on one, you get detailed info on when it appears, when it falls into the earth's shadow, and what direction to look. In addition, you get little sky maps that show where the object will be in a graphic format.

It was partly cloudy here in Arizona last night, but I did locate the International Space Station as it made about a 1 minute appearance in the southern skies before it went behind a cloud bank.

The data for the app comes from a useful website called Heavens Above which has the information that this iPhone app picks up and uses.

The charts are helpful, but the trail of the satellite against the sky is sometimes subtle on the small iPhone screen. Even though I had my GPS radio on, each time I used the app it turned that option off. It does retain your last location, but I think it should just grab the info and not change my settings.

There are other similar apps available for the iPhone, some more expensive; others are free but missing some features that Satellite Visibility has. I think this app has a nice mix for the money.

If all you want is info for passes of the International Space Station, the developer has a US$1.99 app [iTunes app] that skips all the other satellite data.

I think hunting satellites is fun on a nice clear night, so here's a fresh holiday weekend activity you might enjoy.

Click below for a few screen shots: