Orbital Traffic Jam Looms for Space Station

WASHINGTON — The maiden flight of an unmanned European cargo ship is just one of several of tightly-packed arrivals and departures coming up for the International Space Station (ISS).

The European Space Agency's (ESA) first Automated Transfer Vehicle (ATV) is set to launch toward the space station as early as Feb. 22 between a pair of U.S. shuttle missions hauling new modules to the orbital laboratory.

"We've been developing this vehicle for more than 12 years now and we're within touching distance of getting it on orbit," said Alan Thirkettle, the ESA's station program manager, in a Thursday briefing. "We're very excited."

But before the new spacecraft lifts off, astronauts aboard the space station must cast off a spent Russian cargo ship on Feb. 4, then welcome fresh one on Feb. 7 — the same day NASA's shuttle Atlantis is due to haul the ESA's Columbus lab toward the ISS.

The ATV, christened Jules Verne, has a narrow window to dock at the ISS between Atlantis' 11-day mission and the planned March flight of the shuttle Endeavour to deliver the first segment of Japan's Kibo laboratory.

"Things really start to stack up," said NASA's station program manager Mike Suffredini, adding that another Russian cargo ship and a shuttle hauling the centerpiece of Kibo are also due at the outpost in April. "In fact, we've been talking to the crews about being some sort of air traffic controllers; we're just going to have so many vehicles on or around ISS."

Suffredini said that if the ESA's Jules Verne ATV performs flawlessly during its two-week shakedown, NASA may delay Endeavour's planned March 11 launch to allow the cargo ship to dock at the ISS on March 15.

"The key to our success is going to be flexibility amongst all the spacecraft that are coming to the ISS," he added.

Jules Verne's shakedown cruise

The Jules Verne ATV is the first of five ESA cargo ships built to launch fresh supplies to the ISS as payment for European experiments, hardware and astronaut slots on future crews.

"Five flights in total will cover us in our obligations out until 2015," Thirkettle said.

The 1.3 billion-euro ($1.9-billion) ATV is a 20-ton spacecraft capable of hauling a maximum of 7.5 tons of cargo — three times that of Russian supply ships — to the ISS inside its cylindrical shell.

"We're going to be the largest carrier of cargo to the International Space Station," said John Ellwood, ATV project manager.

The first ATV mission will launch atop an Ariane 5 rocket from Europe's spaceport in Kourou, French Guiana. It is expected to run about 15 days, which includes the 10-day flight to the station and a series of demonstration days to test its autonomous docking and collision avoidance systems.

The spacecraft uses an optical rendezvous system that relies on lasers to guide its approach and docking. Astronauts aboard the station won't be able to take remote control, as they can with Russian spacecraft, but could press a red button that would back Jules Verne away should it stray off-course.

If all goes well, the cargo ship could dock as early as March 15, or else take up a holding pattern and rendezvous at the ISS after the Endeavour shuttle flight, ESA officials said.

"We are, I think, very ready to embark on the Jules Verne operations," said Bob Chesson, ESA human spaceflight and operations chief. "We're just waiting now to get the go-ahead."

Tariq is the editor-in-chief of Live Science's sister site Space.com. He joined the team in 2001 as a staff writer, and later editor, focusing on human spaceflight, exploration and space science. Before joining Space.com, Tariq was a staff reporter for The Los Angeles Times, covering education and city beats in La Habra, Fullerton and Huntington Beach. He is also an Eagle Scout (yes, he has the Space Exploration merit badge) and went to Space Camp four times. He has journalism degrees from the University of Southern California and New York University.