Searching for toolbags in space is not exactly standard procedure for stargazers, but they have their chance this week.

Since the astronaut Heidemarie Stefanyshyn-Piper lost her toolbag while on a space walk last week, it has been in orbit around the Earth.

Officials at Nasa had expected the bag, and any embarrassment associated with it, to burn up on reentry into the Earth’s atmosphere. Instead, however, it has presented amateur astronomers with a new and fascinating challenge.

For the rest of this month and into the first days of December the bag should be visible to anyone looking in the right place with a reasonably powerful telescope or binoculars. Calculations have revealed that the best opportunities to see it are early tonight and on Friday.

The task, however, will be to pick out an object the size of a backpack that is in orbit about 250 miles (400km) from the surface of the planet and travelling at more than 15,000mph.

Robin Scagell, of the Society for Popular Astronomy, was scanning space last night for a glimpse of the bag but without success. He intends to try again this evening and expects that it will be visible from Earth until the first week of December.

The angle at which it appears in the sky varies, but tonight it will be at 72 degrees and on Friday at 77 degrees. The bag will be in the southern part of the sky, travelling from west to east. The best viewing times will be at 6.08pm tonight, 6.33pm on Thursday, 5.24pm on Friday and 5.49pm on Saturday. Each appearance will last for three or four minutes.

People on the South Coast will have, weather permitting, the best view. Farther north it will be harder to see and in northern Scotland it will be out of view.

For those determined and lucky enough to find the bag, it will look like a tiny and faint star. “It’s fascinating seeing something that is tiny and has been thrown overboard,” Mr Scagell said. “It’s totally different from anything up in the sky. You can’t learn anything from it but there is the fascination of knowing what it is and seeing it with your own eyes.”

The bag slipped from the grasp of Ms Stefanyshyn-Piper during a repair mission on the International Space Station (ISS) as she became the first woman to lead a space walk.

The station is one of the brightest objects in the sky, but anyone hoping that it will offer a clue to the position of the bag will be disappointed. Although the bag is fairly close to the ISS, it is 100 times dimmer and completes its pass before the station appears. Most astronomers thought that the search of the night sky would be fraught with difficulties.

Robert Massey, of the Royal Astronomical Society, said: “I would be a bit sceptical. It might be possible to pick it up with a telescope or a pair of binoculars, but it will be difficult. You would have to be very sure of the position. It’s like trying to spot a football next to a football pitch but from hundreds of miles away.”

Martin Barstow, of the University of Leicester, added: “I don’t see many people being able to find it. You would have to make a serious effort – I’m not sure I could be bothered.”

Lost in space

— Nasa has lost three lunar buggies on the Moon, although whether this is because astronauts forgot where they parked them remains classified

— Scientists have yet to determine if there is liquid water on the Moon, but they are certain there are no water hazards up there. This did not stop Alan Shepard losing two balls while playing golf during the Apollo 14 mission in 1971

— With a soundtrack by Blur and a charmingly eccentric man in mutton chops at the helm, the Beagle 2 Mars lander was supposed to put Cool Britannia in space. It disappeared amid much embarrassment

Source: Nasa; Times archives

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