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#1 2004-04-22 12:18:24

ERRORIST
Member
From: OXFORD ALABAMA
Registered: 2004-01-28
Posts: 1,182

Re: 747 on board laser

Could a laser such as this be used for propulsion?

http://www.spacedaily.com/news/laser-04 … r-04f.html

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#2 2004-04-22 12:54:41

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: 747 on board laser

Short answer: No

Long answer:
~The beam is much too weak to launch, even microsatelites
~The beam would be difficult to direct at long distances required to reach orbital velocities.
~The "launch" would occur where the air is thin, lowering the thrust of a laser-heated air launch system.
~The atmosphere will dispurse the laser beam after a short distance due to the small size of the optics.
~Short beam firing times due to the chemical nature of the laser compared to the times needed to launch spacecraft.
~Reasonable mechanism for launching a spacecraft with such a laser is unclear.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#3 2004-04-22 13:13:07

ERRORIST
Member
From: OXFORD ALABAMA
Registered: 2004-01-28
Posts: 1,182

Re: 747 on board laser

What about once in space?

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#4 2004-04-22 15:17:48

GCNRevenger
Member
From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: 747 on board laser

In Space... You either:

1: Bring along a propellant of some sort for the laser to heat, thus becoming an externally-heated rocket engine, complete with all the limits that go along with it... specifically, fuel mass per-mole and maximum engine temperature.

2: The laser beam itself exerts light pressure on a mirror of some sort, a variation of the Solar Sail. This is good for interstellar or outter planet probes with very small mass, but not very useful for puttering around the solar system. Very low thrust ensures long trip times and low payloads.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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