Re: LightYear Conversion is Incorrect in Units Package
- To: mathgroup at smc.vnet.net
- Subject: [mg28620] Re: LightYear Conversion is Incorrect in Units Package
- From: Adam Smith<adam.smith at hillsdale.edu>
- Date: Wed, 2 May 2001 03:37:11 -0400 (EDT)
- References: <9cle01$18s@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
The value for a LightYear=9.4605*^15*Meter is correct.
The value 1.0Year SpeedOfLight = 9.454254955488*^15*Meter is for a 365 day year.
The 9.4605*^15 value takes into account the fact that a year is not exactly 365
days but about 365.25 days - Hence the extra day every four years to correct for
this.
Adam Smith
In article <9cle01$18s at smc.vnet.net>, David Park says...
>
>Dear MathGroup,
>
>The LightYear conversion appears to be significantly incorrect in the Units
>package.
>
>Needs["Miscellaneous`Units`"]
>Needs["Miscellaneous`PhysicalConstants`"]
>
>{Convert[LightYear, Meter], Convert[1.0Year SpeedOfLight, Meter]}
>{9.4605*^15*Meter, 9.454254955488*^15*Meter}
>
>I believe that the second value is the correct value. If you agree, you can
>correct the Miscellaneous`Units` package by searching for LightYear and
>pasting in the correct value.
>
>David Park
>djmp at earthlink.net
>http://home.earthlink.net/~djmp/
>
>