Monday, August 31, 1998 Published at 11:57 GMT 12:57 UK
Rogue balloon - now over Russia
The balloon, the size of a 25-storey building, forced flights over the North Atlantic to be re-routed after it went out of control last week.
It entered Russian air space about 7am on Monday [0500 GMT] over the Barents Sea just north of the Arctic island of Spitzbergen.
Russian aviation authorites and airline companies have been told of its position.
The balloon, which would cover an area equivalent to five soccer pitches if deflated, is designed to measure ozone levels.
It drifted free after being launched on August 24 in the western Canadian province of Saskatchewan.
US maritime dispatched a plane surveillance plane from Iceland to look for the balloon using radar, but failed to locate it.
"The radar they were using was for surface searching and they weren't able to detect the balloon in the air," said US Air Force Lieutenant Carla McCarthy.
The British and Canadian airforces were equally unsuccessful.
An Icelandic official said the Canadian attack caused extensive punctures but failed to release the helium gas from the balloon.
But Lieutenant Colonel Steve Wills of the Canadian Air Force said he was not embarrassed by their failure.
"With something like this, which is stationary in the air when the CF-18s are flying very, very fast, it is difficult to shoot it," he said.
Out of control
Instead, it gained altitude and began to drift across Canada and out over the Atlantic Ocean, creating havoc for air traffic.
The balloon does not carry a transponder to warn planes of its presence, but is said to be visible from a distance of about 180km.
Researchers with the Canadian Space Agency, Environment Canada and the University of Denver in the United States were were able to get the atmospheric data they wanted.
But the eight instruments attached, valued at about $640,000 failed to detach as planned.