Far overhead, the International Space Station whips around the planet 248 miles above Earth. You can see it from your home, if there isn't too much light pollution, using an interactive map known as Spot the Station. The ISS circles the globe multiple times per day, and you can track its progress to view it on a clear night.
Spot the Station
The International Space Station is a low Earth satellite that people can live in and is the joint effort of five nations. Participating space programs include NASA (United States), JAXA (Japan), Roscosmos (Russia), CSA (Canada) and ESA (Europe).
On a clear night, observers can see it for themselves from most places on Earth. Look for a bright star moving quickly across the horizon — it appears and disappears quickly.
How Can You Be Sure You're Looking at the ISS?
The Spot the Station program includes alerts that you can sign up for. They tell you when ISS is visible from your current location. A map-based featured tells you when to look for the station in the skies overhead.
Usually, you can expect to get alerts a few times a month. Use them to spot the station when it's orbit passes by you in the night sky.
Sign Up for Alerts
After signing up for the Spot the Station service, you can receive notices whenever the station is visible for at least a couple of minutes. For viewers north of 51.6 degrees latitude, such as those in Alaska, you have to visit the web site because the sightings are so rare.
In the notice, you learn where to look for the space station. Simply note where the sun sets to determine the direction the space station comes from — this will be southwest or northwest.
The height over the horizon appears in degrees. For example, 90 degrees is directly above you. A number below 90 degrees indicates the station will show up between the horizon and directly overhead. It's very bright, so you should catch it easily if you know where to look.
Here's a shortcut. Stretch out a fist toward the horizon. That's approximately 10 degrees. For 40 degrees, look four fist-lengths above the sunset marker on the horizon. For 50 degrees, it's roughly five fist-lengths.
How Often Does the ISS Pass?
Days go quickly for astronauts aboard the space station. It orbits earth in 90 minutes. So, astronauts see the sunset every 45 minutes.
How Much Does the ISS Cost Per Year?
NASA pays about $3 billion per year for the space station and is picking up most of the bills.
It's an awe-inspiring experience to look up and see the ISS zip by. Consider that human beings live, work and breathe in the satellite passing overhead. Perhaps one of them will be looking toward earth near the spot where you stand looking up. (For more space info, please click here.)