October 2002
October 2002
NASA
is starting to think about the future in
earnest once more, no doubt spurred into activity by the likes of
China – just as some were starting to say that NASA might as
well close up shop. We could be in for a good old-fashioned
space-race but with the stakes a little higher than the mere “I
got there first” propaganda doled out by the Apollo/Sputnik
eras. NASA's latest proposal is to put an inflatable space station at
the “Lagrange
Point” L1, which is a point where the Earth's gravity and
the moon's gravity cancel each other out. So a space station can
hover there without actually being in a circular orbit around the
moon.
This gets Mankind several 1,000 km away from the Earth, a lot further than the ISS which is only 400km above us - still close enough to be affected by our atmosphere. But putting the station so far away takes it out of the Earth's magnetic field, putting it at the mercy of solar flares and stronger cosmic radiation. Shielding is a big problem because it weighs so much, and mass is expensive to fire off up into orbit. Unfortunately, the shielding on the International Space Station (ISS) is not performing as well as anticipated. It was hoped that they new, lightweight polythene shields (thick polythene is actually good stuff for stopping radiation) would be somewhat more effective than they has just shown to be. Instead, radiation levels are as high as they were on the old Russian Mir station; enough to increase the chance of dying of cancer by 5%. More, heavier, shields will be needed at L1 or on a trip to Mars. I strongly suggest that NASA considers acquiring that shielding from the moon.
The idea of building space stations at Lagrange points is not new; the late G.K. O'Neill conducted many studies into the feasibility of it in the 1970's. Unfortunately these were done on the basis of the original availability and cost of the US Space Shuttle, which turned out to be far more expensive and flew far fewer flights than originally planned. They also involved the continuation of lunar missions to get the construction material, which the US abandoned as soon as it could. A group called the L5 Society pushed for the resumption of the programme until 1987 when it merged with the National Space Society. If you ever get the chance, read O'Neill's excellent book on the subject, The High Frontier. It was written so long ago that it inspired my interest in space stations, but has since been updated.
A space station at this position would be a good proving-ground for equipment designed to fly to Mars, and well as being a great place to stick the next generation of space-based telescopes. Let us hope that NASA extends the group's current annual budget of US$4m to a more realistic level.
Japan's
Seldom-Seen Shuttle
Japan's Hope-X project to develop a space shuttle of its own had had its budget severely cut back in recent years. But funding of US$22.4m has been given to conduct a range of tests on the craft's steering and navigation systems. It's an unmanned craft, so everything needs to work on automatic. The craft is powered by a jet engine rather than a rocket (despite some images of roaring rockets mistakenly used by some of the world's press), and the first 10 minute test flight from Christmas island involved a top speed of 210km/h and altitude of a mere 600m. It bounced a bit during landing but otherwise worked just fine.
There will be more testing of it later in Sweden, and the speed will be slowly brought up to about half the speed of sound. Being unmanned, it is not expected to challenge the 20 year-old US space shuttle craft. Despite recent setbacks, Japan's space industry is promising a relatively active future with 10 launches of its own H-2A rocket planned over the next 3 years.
America's
Shrinking Shuttle Programme
While Japan takes tiny steps forward, America is failing to move on their space shuttle replacement programme. NASA was supposed to narrow down the choices for a replacement next month as part of a US$4.8 billion project that was meant to cut things back to two choices by 2006. However, there have been administrative and technological problems with replacements and so the selection process has been slugged. They still have to sort out how much involvement the US Department of Defense{sic} has in the programme. The DoD, you may recall, has been blamed for placing unrealistic demands on the original shuttle that made it too big and too heavy to be reused. After ending up with the existing craft which is basically recycled after each flight, the DoD decided it was too expensive to use and ended up sending most of their large payloads up on Titan rockets instead.
NASA also have to weigh up the US involvement in the International Space Station, which this month had a new bit of superstructure delivered by the shuttle, and the requirements for future space stations - if any. In short, NASA doesn't know what it wants, but it knows that it is not the shuttle. Few would be surprised if NASA canceled the whole thing.
Mooning
Around Uranus
And Finally. It's official, as well as a ring, there are now 21 moons around Uranus. Yes, an international team of astronomers boosted the planet's known population of orbiting satellites to 21. The Jet Propulsion Laboratory in Pasadena, California, says 11 astronomers collaborated in the discovery. The new moon, which is as yet unnamed, is about 10 to 20 kilometers across and almost circles Uranus in an irregular orbit. Uranus' moons have traditionally taken their names from characters in the works of William Shakespeare and Alexander Pope, but the new moon has not yet been officially named. Gadzooks, goode fellow. Call ye thyng “Bottom” and be donne wyth itte.
This
edition is also on the web, just point your web browser to
http://olliver.family.gen.nz. vik@olliver.family.gen.nz
"It's
a sad world we live in when freedom itself is rejected because it is
perceived as an unknown" -
Anon.