NASA extends space station life to 2024

This December 22, 2013 NASA image shows astronaut Rick Mastracchio (L) participating in the first Expedition 38 spacewalk designed to troubleshoot a faulty coolant pump on the International Space Station

The International Space Station will operate for an additional four years, or until 2024, the US space agency said Wednesday.

"This is a tremendous announcement for us here in the space station world," said William Gerstenmaier, associate administrator for NASA's Human Exploration and Operations Mission Directorate.

The $100 billion orbiting outpost has been operational for 15 years, and had been expected to remain open to global collaborators until 2020.

More than a dozen countries participate in the space station, which has more living space than a six-bedroom house and comes complete with Internet access, a gym, two bathrooms and a host of science experiments.

NASA said the entire lab is the length of a football field (357 feet, 109 meters).

The International Space Station is the largest space lab ever built, some four times bigger than the Russian space station Mir and about five times as large as the US Skylab.

Although it is near weightless in space, the space station has a mass of 924,739 pounds (419,455 kilograms).

It is maintained by a rotating crew of six astronauts and cosmonauts from the United States, Russia, Europe, Canada and Japan.