The International Space Station celebrated its 12^th anniversary of having a crew continuously onboard, and NASA has unveiled a new app to mark the occasion.

Dubbed "Spot the Station," the new Web app is designed to alert people when the International Space Station (ISS) passes over their heads.

In a statement on Friday, Nov. 2, NASA said the new service would alert people who have registered with ISS tracker, sending a text message or an e-mail with the specific time they can see the space station moving in the sky.

"It's really remarkable to see the space station fly overhead and to realize humans built an orbital complex that can be spotted from Earth by almost anyone looking up at just the right moment," said William Gerstenmaier, associate administrator for human exploration and operations at NASA.

"We're accomplishing science on the space station that is helping to improve life on Earth and paving the way for future exploration of deep space."

The space station is typically visible at dawn and dusk, and appears as the brightest object in the night sky, other than the moon. If the night is clear, the ISS is visible as a point of light moving rapidly, similar in size and brightness to the planet Venus.

People who register with the "Spot the Station" tracker can choose to receive alerts about morning, evening, or both types of sightings. The application will sent an alert a few hours before the space station crosses the spot where the user is located.

The International Space Station's trajectory covers more than 90 percent of the Earth's population, which means that most people can spot the ISS at some point. The "Spot the Station" application will offer the sighting information for more than 4,600 locations across the world. NASA's Johnson Space Center calculates that information several times a week.

"The service is designed to only notify users of passes that are high enough in the sky to be easily visible over trees, buildings and other objects in the horizon," explained NASA.

NASA offers a full list of locations here, and users can sign up with the "Spot the Station" ISS tracker at this link.