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Re: starship-design: Hitching a Ride on a Magnetic Bubble

In a message dated 10/8/00 6:31:37 PM Pacific Daylight Time, stevev@efn.org 

> STAR1SHIP@aol.com writes:
>   > The speed of wind is an average velocity made up of light, gravity 
>   > heat, electro and magnetic components and also mass parts. A well 
> designed 
>   > "light"sail in theory could indeed reach light speed, but practically 
> will 
>   > not near c, for the light and electromagnetic energy captured by the 
> far 
>   > from the effects of the gravity and mass parts is so small in relation 
> the 
>   > mass of the rocket sail, I see little hope of leaving the solar system 
> before 
>   > the solar system gravity fields slows and drags the sail back in an 
>   > elliptical comet like orbit orbit around the sun.
>  What is referred to as the "solar wind" is specifically the charged
>  particle flux that streams away from the Sun, and it's that charged
>  particle flux that would interact with a magnetic sail.
>  According to Lang's _Astrophysical Formulae, 3rd ed._, pp 271-273, the
>  solar wind has two components, one with a velocity of about 400 km/s,
>  another with a velocity of about 800 km/s, as measured near Earth.
>  Solar escape velocity (the table in _CRC Handook of Chemistry and
>  Physics_ doesn't say where, but I'm assuming from the surface since it
>  would vary with distance from the Sun) is about 671 km/s.  So
>  interaction with the fast component of the solar wind could easily
>  propel a spacecraft to escape velocity from the Sun.

I was looking for something a little more reliable than the Lang's 
_Astrophysical Formulae, 3rd ed._, pp 271-273 or the solar wind and it's many 
more than two components :-).

Needing solar wind power at a specific time to keep rocket from falling into 
a planet gravity well during close orbital manuevers seems fool hardy.

Partial quote----
For Two Days The Solar Wind Stopped 
by Paul Winter 

Back in May 99, the solar wind stopped for two days. Actually, it dropped to 
2% of its normal density and to half its normal speed. Although the solar 
wind varies greatly, this was the most drastic and longest-lasting decrease 
ever observed. NASA sat on the story for five months. Squished it flat. When 
NASA finally released that information, it was too old for newspapers to carry

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