Cosmonaut prepares for golf stunt

[Sonia]

A Russian cosmonaut is preparing to hit a golf ball during a spacewalk outside the International Space Station (ISS).

http://news.bbc.co.uk/1/hi/sci/tech/6164988.stm

[xelasnave]

Thanks for posting that Sonia:thumbsup: . I suspect the guy who wants to put the inflatable hotel up there is behind this:D .
Disappointing that he is not going to really smash the ball... now I know why the renewed interest in manned missions ..they are going to put some more holes on the Moon no doubt:lol: :lol: :lol: .
alex

[Shawn]

Golf.
The best way to spoil a good walk.
Winstone Churchill said that,,:)

[sheeny]

I found this in news @ nature this morning,

Al.

Golf in space

Cosmonaut space stunt will put balls into orbit.
Katharine Sanderson (http://www.nature.com/news/about/aboutus.html#Sanderson)

What would you do if you were taking a stroll in space? Take some souvenir snaps? Do some somersaults in zero gravity? Or perhaps you would practice your golf swing.

That is exactly what Russian cosmonaut Mikhail Tyurin is planning to do during his space walk from the international space station (ISS) later today.

The stunt is a promotional gimmic for Canadian club maker Element 21 Golf, which is paying the Russian space agency for Tyurin's time. Unlike most commercial gimics, this one has caused massive debate about safety within government agencies — NASA has spent months deciding whether or not to agree to the ploy.

Tyurin will gently tap up to three specially designed golf balls, with a mass of just 3 grams, at a maximum speed of 1.2 metres per second. He will aim backwards, away from the station, to minimize the chances of causing any damage to it.

Once clear of the station, the ball will have a sufficient de-orbital trajectory that it will not pose a re-contact hazard to the station," says NASA spokesperson Grey Hautaluoma. If a ball were to hit, it could do serious damage to the solar panels.

Predictions for the ball's survival time vary. NASA predicts the ball will drop out of orbit and burn up in the Earth's atmosphere within 3 or 4 days. But the Russian space agency Roscosmos and the Canadian golf equipment firm sponsoring the event have suggested that the ball will keep going for up to 3 years. NASA suggests that this longer estimate may be the result of assuming that the ball will be a regular 45 grams, rather than the slimmed-down version actually being used in the stunt — a lighter object is much more heavily influenced by the tiny amount of atmospheric drag at that altitude, which should degrade its orbit more quickly.

Round and round

The direction the ball is hit is critical. At the point of contact, the ball and the ISS are, obviously, in the same circular orbit. As soon as the ball's velocity changes, so will its orbit. If hit forwards, the ball will speed up relative to the ISS and go into a higher-energy elliptical orbit; if hit backwards, it will slow down and drop into a lower-energy orbit.

In either case, the golf ball will always return one orbit later to the exact spot it was hit. This doesn't mean that the ISS is in danger of a golf-ball bombardment explains ex-astronaut Jeffrey Hoffman, now at the Massachusetts Institute of Technology, Cambridge. "The period of the orbit is changed, so although the ball comes back to exactly the same point in space one orbit later, it will get there before or after the space station does. If the ball is hit backwards, as planned, its orbital period will be decreased, and it will get back before the ISS returns to that point." And without thrusters to keep the ball in place, its orbit will quickly spiral in towards the Earth, taking it out of the path of the ISS altogether.

The ISS orbits the Earth 15.72 times a day. After a few days, the golf ball could be whipping around a bit more than 16 times a day, estimates William Ailor, director of the Centre for Orbital and Reentry Debris Studies in Los Angeles. That would put it thousands of kilometres away from the ISS on its nearest pass.

The one danger is if the ball is hit sideways at exactly 90 degrees. It would then come back and wallop the station half an orbit later, says Hoffman. Thankfully Tyurin won't be able to slice his shot, as the ball will be guided backwards by a restraining mechanism with a 60-degree safety cone.

Need for speed

If Tyurin were to give it his all, how fast would the ball go?

Terrestrial golfers would typically hit a ball with a force that would see it accelerate from 0 to 160 kilometres an hour in about one two-thousandth of a second, although for professional golfers the ball might get up to more than 200 kilometres an hour, says Steve Mather, a sports scientist from Nottingham University, UK.

The lack of air resistance in space would make little difference to this speed, says Mather. More restricting would be the bulky space suit worn by the golfer. "He's not going to get the kind of swing Tiger Woods gets," says space-walking veteran Hoffman. "Tiger Woods wouldn't get a Tiger Woods swing in a space suit." So Tyurin's planned tap might be more accurately described as a gentle putt, probably done one-handed.

Tyurin will have to be well anchored throughout his golfing adventure. Golfers wear spiked shoes for good reason — to keep them in one spot and compensate the reaction from the force of hitting the ball. "We rely on the fact that gravitational acceleration keeps us on the floor," says Mather. If Tyurin were not tethered, the equal and opposite force of hitting the ball would send him off in the opposite direction.

The stunt will probably remind space nostalgists of Alan Shepard — the only person to ever play golf on the Moon, which he did during the 1971 Apollo 14 mission. The fate of that ball is uncertain; presumably future colonists might one day find it.