TysonTweet.frink

View or download TysonTweet.frink in plain text format

// Neil deGrasse Tyson claimed that the sun set directly west every day for
// people on the the equator.  Huh?!
// https://twitter.com/neiltyson/status/246033957014093824

use sun.frink

lat = 0 degrees North
long = 0 degrees West
lowest = 360 degrees
lowestDate = now[]
highest = 0 degrees
highestDate = now[]

format = ### yyyy-MM-dd HH:mm:ss ###
println["<TABLE>"]
for date=#2012-01-01 12:00 UTC# to #2013-01-01 12:00 UTC# step 1 day
{
   sunset = sunset[date, lat, long]
   [az, alt] = refractedSunAzimuthAltitude[sunset, lat, long]
   geoAz = (az + 180 degrees) mod circle  // Turn Meeus azimuth to geodetic
   println["<TR><TD>" + (sunset->[format, "UTC"]) + "<TD>" + format[geoAz,"degrees",3]]
   if (geoAz < lowest)
   {
      lowest = geoAz
      lowestDate = sunset
   }
   if (geoAz > highest)
   {
      highest = geoAz
      highestDate = sunset
   }
}

println["</TABLE>"]
println["Most southerly sunset is " + format[lowest, "degrees", 3] + " on " + (lowestDate->[format, "UTC"])]
println["Most northerly sunset is " + format[highest, "degrees", 3] + " on " + (highestDate->[format, "UTC"])]

println["The sun sets as much as " + format[270 degrees - lowest, "degrees", 3] + " south of due west."]
println["The sun sets as much as " + format[highest - 270 degrees, "degrees", 3] + " north of due west."]


View or download TysonTweet.frink in plain text format


This is a program written in the programming language Frink.
For more information, view the Frink Documentation or see More Sample Frink Programs.

Alan Eliasen was born 17419 days, 16 hours, 43 minutes ago.