How to See the Space Station Pass Overhead

Have you ever watched the International Space Station pass overhead? I've seen it several times.

It looks like a star moving across the sky. Often it is very bright, almost as bright as Venus. If you have ever seen a satellite, the ISS is generally much brighter than most other satellites you can see. Usually you have to get out of the city to see a regular satellite, but the ISS is often visible from the city on a clear night.

When the Space Shuttle is visiting the Space Station, it usually spends a day or two to catch up to the space station, and it is sort of amazing to see both of them passing overhead, one bright star following another.

This website tells you when and where to look to see the Space Station, and other big, bright satellites like the Hubble Space Telescope: http://www.heavens-above.com/

This might look like a long explanation but it is really very easy to do. You tell the site where you are --- it tells you where to look.

1. I usually use the site anonymously and select the Select your location from our huge database option.


2. On the Select Country screen, select the country where you will watch for the satellite.


3. On the Select Town screen, enter the city or town where you will watch for the satellite.


4. If more than one match comes up in the Town Search Results screen, select the right one from the list.


5. The Main Menu screen appears and shows you some summary info about the observing site you have selected and provides links to all the satellites you can get predictions for.
   If you want predictions for the International Space Station, select ISS.
   If the Space Shuttle is up and you want predictions for it, select STS-###. (That's Space Transportation System and the mission number)
   If you want predictions for the Hubble Space Telescope, select HST.
   There are several other satellites you can select as well.


6. The next screen shows the visible passes for the next ten days for the satellite you selected. I attached the screen I got when I selected the Space Station for my area.

Here's what the chart means:

I ran the predictions on the 8th, but you can see there are no visible passes until the 12th. Dang! This is because the angle of the orbit does not bring the station over my location at night at a time when it is still illuminated by the sun until then. It might still go directly overhead in the few days between the 8th and 12th, but it's either in the daytime, or late at night in the earth's shadow, when it cannot be seen.

The Mag column tells you how bright it is going to be. Small numbers are brighter. Negative numbers are brightest. The brightest pass on my chart is the Feb 16 pass with a magnitude of -2.2.

You have both the Start Time and End Times, so you can see how long the pass will last. Feb 16 is also a long pass, about 5 minutes.

You have both the Start Az and End Az. Az stands for azimuth, which is basically the direction, so you can see where it's going to start in the sky and where it is going to end. The Feb 16 pass, starts in the NW (North West) and ends in the SE (South East). Basically this pass starts at one side of the sky and ends at the opposite, so it goes almost directly overhead. That's why it is a long pass and why it is so bright.

The Max Altitude columns tell you how high in the sky it will get and when and where that will happen. Al stands for altitude and tells you the angle off the horizon --- 0 is on the horizon and 90 is straight overhead. The Feb 16 pass has a maximum altitude of 70 degrees, so it goes almost directly overhead.

So here's what I would do if I wanted to see the Feb 16 pass, which looks like a pretty good one for my location. (This is only for my location --- you need to run the chart for yourself to get accurate times an angles.)

I'd make sure it was a clear night. Any haze will ruin it. It's possible to see it from my backyard, but if I had the opportunity I'd go to a dark location with a broad view of the sky. And even better I'd bring a friend along. I might bring my binoculars too just to make it that much brighter. Looking at the sky through good binoculars is great, but it's not really necessary because the Space Station is so bright.

The pass is starting at 18:39 (6:39 pm), so I'd want to be there early. There may still be twilight then, but if it was dark, it would be good to let the eyes adjust to the darkness.

A few minutes before 6:39, I'd say, "Hey, have you ever seen the Space Station?"

The Friend would say, "What the hell are you talking about?"

I'd say, "The Space Station is coming up right over there at 6:39."

They'd say, "You're so full of crap!"

I'd start to look toward the north west scanning above the horizon for a moving "star." When it popped up, I'd say, "Wooooo-hoooo! There goes the freakin' Space Station!"

It's a fun trick. Seeing that little light moving across the sky and knowing people are living and working there right now is kind of a blast. Try it a few times before you decide to blow someone's mind just to be sure you know how it works. And make sure your watch is set for the exact time.

Here a few more tips about viewing the station:

Occasionally they change the orbit of the station in order to avoid space junk or to re-boost the orbit back to it's specified altitude. So if you get a 10-day prediction and plan on watching a pass a few days away, it's a good idea to get the another prediction as near as possible to the day you plan to watch, because the orbit may have been altered in the meantime. Be sure to do this especially if the Space Shuttle is at the station. They often use the shuttle engines to boost the station, so the predictions may need to be updated frequently during the time the shuttle is there.

Also, the example I gave earlier was for what would be a great pass directly overhead, lasting about 5 minutes, and very bright. Often they will just pass over one side of the sky and not get as high as you would want, so be sure to use your local chart to determine how high, how long, and how bright it is going to be.

Have fun watching the International Space Station, and be sure to wave as it goes by!