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Topic: Introducing the United (fps) System
Replies: 87   Last Post: May 4, 2000 6:25 PM

 Messages: [ Previous | Next ]
 David C. Baker Posts: 18 Registered: 12/12/04
Re: Introducing the United (fps) System
Posted: May 4, 2000 6:25 PM

Gene Nygaard wrote in message <8ehbg6\$9r8\$1@nnrp1.deja.com>...
>In article <GB4PItAQduC5EwNS@earthpoetry.demon.co.uk>,
> rc@earthpoetry.demon.co.uk wrote:

>> In article <390adc8a.3278162@news.nccray.com>, Gene Nygaard
>
>> >
>> >With SEVEN significant digits? Get real.
>> >
>> >Alpha Centauri might be 41 Pm away.
>> >

>> Chill out. It was only done for effect. Imagine the line of metres.
>> 41 Pm =c metres.

>
>If that was your goal, there is still a sizable group of astronomers who
>cling to an old metric system as tenaciously as the American public
>clings onto their miles. To them, this distance should be expressed in
>the ideal metric units for the distance between stars (they'd normally
>use scientific notation, of course) as
>
> 4 100 000 000 000 000 000 cm
>
>They also think that ergs per second are the ideal units for measuring
>the power of stars, etc.
>
>--
>Gene Nygaard
>http://ourworld.compuserve.com/homepages/Gene_Nygaard/
>
>
>Sent via Deja.com http://www.deja.com/

Does anyone know why that is? I have an an astronomy and cosmology book from
the '60s which states stellar masses in grams, distances in cm, and power in
ergs/s. A more recent book by Alan Guth also uses these for large measures.
Surely astronomers don't go look for lightbulbs rated in ergs per second.
Why do they use these units for large measures?

Of course, I don't believe these units should be discarded and replaced with
SI, but instead they are only appropriate for small things. On my desk I use
a centimeter ruler. I use meters for larger things. I use grams for things
which are hand sized, and kg for larger. I use watts for most power
measures, and joules for energy. I would use ergs in the right situation.
Why do astronomers use these?

David C. Baker

Date Subject Author
4/21/00 Mark Mallory
4/21/00 Richard Carr
4/21/00 Erik Max Francis
4/21/00 Uncle Al
4/21/00 Gregory L. Hansen
4/21/00 William L. Bahn
4/22/00 gandg@snet.net
4/22/00 Gregory L. Hansen
4/22/00 Uncle Al
4/23/00 Michael Varney
4/22/00 Jeffrey Gauch
4/22/00 RC
4/24/00 Paul Richards
4/24/00 Russell Harper
4/24/00 Jim Carr
4/24/00 briggs@eisner.decus.org
4/30/00 Chris Thompson
4/22/00 gandg@snet.net
4/22/00 gandg@snet.net
4/22/00 Jeffrey Gauch
4/23/00 Jim Carr
4/24/00 Paul Richards
4/24/00 briggs@eisner.decus.org
4/22/00 gandg@snet.net
4/22/00 Gregory L. Hansen
4/22/00 Ben Kraines
4/23/00 Ben Kraines
4/24/00 Gregory L. Hansen
4/23/00 gandg@snet.net
4/23/00 Jeffrey Gauch
4/23/00 theresa knott
4/24/00 Jeffrey Gauch
4/24/00 William L. Bahn
4/24/00 theresa knott
4/23/00 gandg@snet.net
4/23/00 gandg@snet.net
4/23/00 Gregory L. Hansen
4/23/00 Jeffrey Gauch
4/23/00 gandg@snet.net
4/23/00 theresa knott
4/24/00 William L. Bahn
4/23/00 gandg@snet.net
4/23/00 Ben Kraines
4/24/00 Jeffrey Gauch
4/24/00 Jeff Gauld
4/24/00 William L. Bahn
4/24/00 Jeff Gauld
4/24/00 William L. Bahn
4/24/00 Jeffrey Gauch
4/24/00 theresa knott
4/25/00 Gene Nygaard
4/25/00 William L. Bahn
4/24/00 Jeff Gauld
4/24/00 Jeff Gauld
4/24/00 Jeff Gauld
4/24/00 William L. Bahn
4/24/00 ÃÂ. ÃÂÃÂ¥ÃÂ«ÃÂ¥ÃÂ£ÃÂ¨ÃÂ­
4/24/00 gandg@snet.net
4/24/00 Gregory L. Hansen
4/24/00 gandg@snet.net
4/24/00 Gregory L. Hansen
4/24/00 Jeff Gauld
4/24/00 Ben Kraines
4/24/00 RC
4/25/00 Martyn Harrison
4/28/00 Stephen Poley
4/28/00 Paul Schlyter
4/29/00 Jim Carr
4/30/00 Stephen Poley
5/1/00 briggs@eisner.decus.org
5/2/00 Russell Harper
4/24/00 gandg@snet.net
4/24/00 Jeff Gauld
4/25/00 Ben Kraines
4/24/00 Jeff Gauld
4/28/00 RC
4/29/00 RC
4/29/00 Gene Nygaard
4/29/00 RC
4/30/00 Gene Nygaard
5/1/00 Mehdi TIBOUCHI
5/4/00 David C. Baker
4/30/00 gandg@snet.net
4/30/00 RC