Number of miles in a light year is prime!

Stargate38 · 2012-01-08, 19:35

Did you know that the number of miles in a light-year, rounded to the nearest integer, is prime? Here's the number:

5874601673407

The real value is 5874601673407+2/(11*127) miles. Google doesn't show any results for "5874601673407 prime number", so I guess no one knew.

diamonddave · 2012-01-08, 19:45

Quote:

Originally Posted by Stargate38

Did you know that the number of miles in a light-year, rounded to the nearest integer, is prime? Here's the number:

5874601673407

The real value is 5874601673407+2/(11*127) miles. Google doesn't show any results for "5874601673407 prime number", so I guess no one knew.

Is it this year light year? Because this year we have a leap second on June 30th.

Stargate38 · 2012-01-08, 19:56

It's the definition for a non-leap-year. In other words, it worked for 2009, 2010, and 2011, and it will also work for 2013, 2014, 2015, and every year that isn't of the form 4*x

Mini-Geek · 2012-01-08, 20:14

According to Wikipedia, a light year is actually defined as the distance light travels in one Julian year, i.e. 365.25 days precisely, (regardless of leap years and leap seconds) which is about 5,878,625,373,183.608 miles. 5878625373184 = 2¹⁰ * 5107 * 1124113. You've given the distance for 365 light days. While still an interesting bit of trivia, that likely explains the lack of others noting it previously (at least, as far as you could find).

Dubslow · 2012-01-08, 20:40

Quote:

Originally Posted by Mini-Geek

5878625373184

fixd

Flatlander · 2012-01-08, 21:46

This thread could be why we don't attract women.

ATH · 2012-01-09, 01:04

I'm not sure what is the official definition of a lightyear, there are many different values:

Wikipedia: 5,878,625,373,183.608 miles (9,460,730,472,580.8 km)
Online Conversion: http://www.onlineconversion.com/length_all.htm
Light year (Julian): 5,878,625,373,200 miles (9,460,730,472,600 km)
Light year (Tropical): 5,878,499,814,100 miles (9,460,528,404,900 km)
Light year (traditional): 5,874,601,673,400 miles (9,454,254,955,500 km)

My old Texas TI-85 calculator conversion: 5,878,499,814,135.1 miles (9,460,528,404,879.4 km)

science_man_88 · 2012-01-09, 01:44

Quote:

Originally Posted by ATH

I'm not sure what is the official definition of a lightyear, there are many different values:

Wikipedia: 5,878,625,373,183.608 miles (9,460,730,472,580.8 km)
Online Conversion: http://www.onlineconversion.com/length_all.htm
Light year (Julian): 5,878,625,373,200 miles (9,460,730,472,600 km)
Light year (Tropical): 5,878,499,814,100 miles (9,460,528,404,900 km)
Light year (traditional): 5,874,601,673,400 miles (9,454,254,955,500 km)

My old Texas TI-85 calculator conversion: 5,878,499,814,135.1 miles (9,460,528,404,879.4 km)

http://www.google.ca/search?sourceid...w=1600&bih=775

LaurV · 2012-01-09, 02:01

Quote:

Originally Posted by Flatlander

This thread could be why we don't attract women.

13 points for the joke! (could not give 10, is not prime, and 11 is not an exponent of a mersenne prime...). Nice one! But next time, talk in your name only

Dubslow · 2012-01-09, 02:13

Quote:

Originally Posted by ATH

I'm not sure what is the official definition of a lightyear, there are many different values:

Wikipedia: 5,878,625,373,183.608 miles (9,460,730,472,580.8 km)
Online Conversion: http://www.onlineconversion.com/length_all.htm
Light year (Julian): 5,878,625,373,200 miles (9,460,730,472,600 km)
Light year (Tropical): 5,878,499,814,100 miles (9,460,528,404,900 km)
Light year (traditional): 5,874,601,673,400 miles (9,454,254,955,500 km)

My old Texas TI-85 calculator conversion: 5,878,499,814,135.1 miles (9,460,528,404,879.4 km)

http://www.iau.org/public/measuring/

Quote:

For studies of the structure of the Milky Way, our local galaxy, the parsec (pc) is the usual choice. This is equivalent to about 30.857×1012 km, or about 206,000 AUs, and is itself defined in terms of the AU – as the distance at which one Astronomical Unit subtends an angle of one arcsecond. Alternatively the light-year (ly) is sometimes used in scientific papers as a distance unit, although its use is mostly confined to popular publications and similar media. The light-year is roughly equivalent to 0.3 parsecs, and is equal to the distance traveled by light in one Julian year in a vacuum, according to the IAU. To think of it in easily accessible terms, the light-year is 9,460,730,472,580.8 km or 63,241 AU.

Mini-Geek · 2012-01-09, 02:17

Quote:

Originally Posted by ATH

I'm not sure what is the official definition of a lightyear...

Wikipedia's source is http://www.iau.org/public/measuring/, which looks official enough to me! Besides defining the "year" as 365.25 days, it gives the distance in KM, which converts to the number I gave.
Of course, non-standard usages can be used anyway (and are, given your links; which also show a level of precision too low to give the precise integer), but regardless, an official standard definition exists.

2012-01-08, 19:35	#1
Stargate38 "Daniel Jackson" May 2011 14285714285714285714 1010000011₂ Posts	Number of miles in a light year is prime! Did you know that the number of miles in a light-year, rounded to the nearest integer, is prime? Here's the number: 5874601673407 The real value is 5874601673407+2/(11*127) miles. Google doesn't show any results for "5874601673407 prime number", so I guess no one knew.

2012-01-08, 20:14	#4
Mini-Geek Account Deleted "Tim Sorbera" Aug 2006 San Antonio, TX USA 10AB₁₆ Posts	According to Wikipedia, a light year is actually defined as the distance light travels in one Julian year, i.e. 365.25 days precisely, (regardless of leap years and leap seconds) which is about 5,878,625,373,183.608 miles. 5878625373184 = 2¹⁰ * 5107 * 1124113. You've given the distance for 365 light days. While still an interesting bit of trivia, that likely explains the lack of others noting it previously (at least, as far as you could find). Last fiddled with by Mini-Geek on 2012-01-08 at 20:19

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2012-01-08, 19:56	#3
Stargate38 "Daniel Jackson" May 2011 14285714285714285714 643 Posts	It's the definition for a non-leap-year. In other words, it worked for 2009, 2010, and 2011, and it will also work for 2013, 2014, 2015, and every year that isn't of the form 4*x

2012-01-08, 21:46	#6
Flatlander I quite division it "Chris" Feb 2005 England 31×67 Posts	This thread could be why we don't attract women.

2012-01-09, 01:04	#7
ATH Einyen Dec 2003 Denmark BDC₁₆ Posts	I'm not sure what is the official definition of a lightyear, there are many different values: Wikipedia: 5,878,625,373,183.608 miles (9,460,730,472,580.8 km) Online Conversion: http://www.onlineconversion.com/length_all.htm Light year (Julian): 5,878,625,373,200 miles (9,460,730,472,600 km) Light year (Tropical): 5,878,499,814,100 miles (9,460,528,404,900 km) Light year (traditional): 5,874,601,673,400 miles (9,454,254,955,500 km) My old Texas TI-85 calculator conversion: 5,878,499,814,135.1 miles (9,460,528,404,879.4 km)