Re: Mt.Wilson

On Tue, 13 Dec 2005 16:27:53 -0800, G.T. wrote:

> Can you explain this phenomenon? I've been up to 12,000 ft at night and
> never had trouble seeing stars. I don't think I've been higher than
> that during the night, nor during the day, actually. What's the
> difference between 12,000 ft and 16,000 ft (other than the obvious 4000 ft)?

A lot less oxygen. The decrease in atmospheric pressure is approximately
exponential so the higher you go the more of a difference each incremental
increase makes. Think of going from sea level to 4000 feet. Most people
won't notice any change. 4000 to 8000 is noticeable but not huge. 8000 to
12,000 matters a lot and acclimatization really matters (which certainly
isn't true for going from sea level to 4000 feet).

Even when fairly well acclimatized at base camp at 15,000 feet I ran into a
wall at about 16,500 on that climb (the next camp was at about 17,200). I
was the strongest in the group when we started that day and was left behind
half-way up when I went from an easy stroll to five breaths per step. I
went from good to bad in about 500 feet or less. I understand even some
professional climbers have ceilings they just can't penetrate.

This is what makes it so amazing that people can go to great heights. The
higher you go the greater the effect of going even higher. How some
climbers can do what they do is beyond me.

Mike Simmons
.

Relevant Pages

  • Re: Mt.Wilson
    ... Think of going from sea level to 4000 feet. ... 12,000 matters a lot and acclimatization really matters (which certainly ... Even when fairly well acclimatized at base camp at 15,000 feet I ran into a ... professional climbers have ceilings they just can't penetrate. ...
    (sci.astro.amateur)
  • Re: OT: This system must have been written in Ruby...
    ... sea level and passed the reading on to the automatic control system, ... possible to be flying at 8 feet below sea level. ... I wonder what Kenny's flight control software would have done ...
    (comp.lang.lisp)
  • Re: SEA LEVEL
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    (sci.geo.satellite-nav)
  • Re: OT: This system must have been written in Ruby...
    ... sea level and passed the reading on to the automatic control system, ... possible to be flying at 8 feet below sea level. ... Ordinary good code would have identified the physically impossible altitude change as, um, impossible, rejected it altogether, and fallen back on extrapolation. ...
    (comp.lang.lisp)
  • Re: I plead "Guilty"
    ... that is about 55 feet above sea level (or 188 feet depending on the ... source) I, on the other hand, am at 17 feet above sea level and about ... I am 500 or so Km from the Atlantic, but only about 60 metres above sea level, ... and some 30 metres above the Ottawa River. ...
    (sci.military.naval)