# Sky-high ladder may be feasible

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Question: What if scientists built a ladder for climbing to the sky — like Jack's beanstalk — so high you could ascend to a space colony, stay a while, then climb back down to home?

Answer: Russian scientist Yuri Artsutanov first dreamed up this wonderful notion in 1960, and theorists have run with it, says Jay Ingram in ""The Barmaid's Brain.""

You begin with the idea of a ""geosynchronous"" satellite orbiting over the equator at 22,000 miles up, so as to go at the same speed as the turning Earth and appear from below to be hovering. Communications satellites do just that. Key engineering realization: If you tried to build from the bottom up, the ladder (tower) would collapse under its own weight.

So you set your factory in orbit and ""hang"" the ladder on down.

But get this — a second strand of ladder must be built out toward space as a counterweight: Now its centrifugal force offsets the colossal growing weight below. Never mind that no known materials come close to being strong enough for the job, or that the upper strand must be 66,000 miles long (in lessened gravity), for a total ladder of more than 80,000 miles!

Of course you wouldn't climb this like a normal ""ladder"" — more an elevator with cars moving up and down in some sort of open framework. In all likelihood, it'll never be done — roughly equivalent to building a bridge around the world — but who knows, says Ingram. Unlike Star Trek's holodecks or warp drive, at least the ladder may be feasible.

Going up?

Question: ""Nobody is considered dead until warm and dead."" What's meant by this wilderness medicine rule-of-thumb?

Answer: A person in deep hypothermia following an accident in extreme cold may lose vital signs but be revivable once inside, says Frances Ashcroft in ""Life at the Extremes"":

A 29-year-old Norwegian woman in a skiing accident was wedged between rocks and ice and drenched by a waterfall. When rescuers arrived over an hour later, she was clinically dead, her body core at 13.7 C. They began CPR and headed for the hospital, where a resuscitation team was able to revive her.

When a 5-year-old boy fell through the ice on a river, he was trapped without air for 40 minutes. When frogmen fished him out, he had no pulse, wasn't breathing and looked blue-gray. But after two days on a respirator, he recovered consciousness and started to talk. Eight days later, he was home with no apparent brain damage. Small children usually do best in such ordeals because ""they are quickly chilled, their oxygen demands fall rapidly, and they enter a state of suspended animation.""

Question: Neighbor spots you out in your back yard at night standing on your head and looking off toward a fat, full, fabulous summer moon. Now what are you trying to prove?Answer: Nothing less than that the classic ""moon illusion"" is pure psychology and not based on atmospheric effects as many people think.

Check it out: The lunar orb looks charmingly huge on the horizon, then seems to shrink as it climbs in the sky.

This was first noted millennia ago. A common explanation is that comparison to terrestrial objects such as trees or towers makes the low moon look bigger, but this also occurs at sea. It disappears if you view the moon upside down or through a tube, suggesting perceptual cues are involved. Though not well understood, the illusion is so powerful artists invariably paint a horizon moon (or sun) several times bigger than it's true fraction of the sky.

Send STRANGE questions to brothers Bill and Rich at strangetrue@compuserve.com