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Olympic torch goes to space - but without the flame

bobmcdonald-190.jpgBy Bob McDonald, Quirks & Quarks

The Olympic torch began its out-of-this-world relay this week when it was carried up to the International Space Station by Mikhail Tyurin aboard a Russian Soyuz rocket. But they don't dare light it.

The torch will be taken outside the station and handed off during a spacewalk by two Russian cosmonauts, which will make it the longest distance ever covered by a torch relay. The orbiting spacemen travel eight kilometers every second, so even if the handoff takes only a minute, they will have travelled 480 km in that time.

But there will be no flame flickering from the end of the torch, because to do so in space would be very difficult and extremely dangerous.

First of all, there is almost no air outside the Space Station, which means no oxygen to fuel a flame. The only way to create a flame in space is to use rocket fuel, which is made up of liquid oxygen and liquid hydrogen. Both of these super-cold liquids must be kept more than 200 degrees centigrade below the freezing point, which would make the torch a little chilly on the hands.

An alternative would be solid rocket fuel, such as the type used on the solid rocket boosters of space shuttles. It is easier to handle, but it burns explosively. In either case, lighting the torch with rocket fuel would produce a bright flash lasting less than a second, rather than a nice flame, and it would probably take the arm off the person holding it. Not a good idea.

Inside the Space Station, there is a normal atmosphere where the torch could be lit, but that would threaten the lives of everyone on board. In space, flames behave differently than they do on Earth because the hot gases do not rise above the cooler surrounding air. Everything in orbit, including gases, is weightless, so the heat does not rise and the flame forms a circular blob, or will point in whatever direction the air is circulating.

If the torch sets something larger on fire, and burning pieces start coming off, they will float around in all directions, spreading the blaze very rapidly. Talk about "great balls of fire."

Fire is a huge issue in the closed environment of the Space Station because there is a limited supply of oxygen. If it can't be extinguished, the module where the fire is burning has to be sealed off to let it burn out, which would render that module useless. Most of the modules on the station are attached end to end, so if one of them is cut off, it is possible to isolate one end of the complex from the other.  

Carrying the Olympic torch to space, as well as to the North Pole and the bottom of Lake Baikal, is, according to Russian president Vladimir Putin, a demonstration of the country's technical achievements. But taking it to these extreme environments gets away from the original purpose of the huge relay, which is not about the torch itself, but about the flame.

During the Ancient Olympics in Greece, the flame represented the fire that Prometheus stole from Zeus. Today, the fire is lit using sunlight reflecting off a parabolic mirror at the Temple of Hara at the site of those games in Olympia. It is then relayed by runners who carry the fire to the host city.

Great efforts have been made to keep the flame burning throughout the journey on boats, planes and even under water, so by the time it gets to the cauldron at an Olympic stadium, it is still part of the original flame.

Unfortunately, this year, the torch has been relit several times and will be lit again when it returns from space. So, while the unifying symbolism of the torch floating above the Earth is a powerful one, let's hope someone is keeping the fire burning down below.