Space Station to Put on Sky Show This Weekend

The International Space Station will be extra visible to observers on Earth this weekend ? sometimes up to five times a night ? thanks to some favorable sun angles that will light up the orbiting space lab.

The space station flies about 220 miles (354 km) overhead, circling the globe once every 90 minutes. Usually, the station is invisible to skywatchers on Earth during some of those orbits because the sun isn't shining on it.

However, over the next few days, the station's path will align with Earth's day-night terminator, keeping the spacecraft in nearly constant sunlight, according to the website Spaceweather.com, which monitors spacecraft sightings and space weather.

That means that every time it flies overhead, skywatchers graced with clear skies should be able to spot the space station as a moving star that can sometimes appear as bright as Venus. The rare solar line-up ends on Monday.

The station is currently home to six astronauts ? three Americans and three Russians. Cosmonaut commander Alexander Skvortsov is leading the Expedition 24 mission.

Construction on the huge space station began in 1998 and it is now 98 percent complete. Five different space agencies and 16 countries have been working together to build the $100 billion space station, which is the largest human-made structure in space.

From end-to-end, the space station's main truss ? which serves as its metallic backbone ? is longer than a football field. The outpost's wing-like solar arrays also serve as giant reflectors when they catch sunlight, and make the space station easily visible to the unaided eye. [How to spot satellites]

There are several ways to find out when the International Space Station may be flying over your area. Information on when the spacecraft will be visible over your city can be found at this NASA website.

You can also find detailed viewing opportunities by searching the Internet for one of these four popular websites:

• Chris Peat's Heavens Above
• Science@NASA's J-Pass
• NASA's SkyWatch
• Spaceweather.com

Each website will ask for your zip code or city name and respond with a list of suggested spotting times. Predictions computed a few days ahead of time are usually accurate within a few minutes. However, they can change due to the slow decay of the space station's orbit and periodic reboosts to higher altitudes. It is a good idea to check frequently for updates.

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