Difference between revisions of "Time-traveller achievement"

From Geohashing
imported>Mckaysalisbury
(Ahh, I see what you mean now. Let me clarify and clean up.)
imported>Benjw
(more tidying up)
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** Geohashers near longitude 0° or 180° might be lucky and not have to travel far at all.
 
** Geohashers near longitude 0° or 180° might be lucky and not have to travel far at all.
 
* Be in a mirror graticule and get extremely lucky.
 
* Be in a mirror graticule and get extremely lucky.
** Because graticules that touch across the equator or the prime meridian or the 180° meridian mirror each other, there is a very small chance, if you're standing on the border between them, you could be in the circle of uncertainty for two hashpoints simultaneously.
+
** Because graticules that touch across the equator or the prime meridian or the 180° meridian mirror each other, there is a very small chance, if you're standing on the border between them, that you could be in the circle of uncertainty for two hashpoints simultaneously.
 
*** For those graticules that touch across the equator, this happens if the latitude of the hashpoint is less than 0.000036°.
 
*** For those graticules that touch across the equator, this happens if the latitude of the hashpoint is less than 0.000036°.
*** For those that touch across the prime or 180° meridian, the longitude of hashpoint must be below longitude can be calculated from 0.000036° / cos(Latitude).
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*** For those that touch across the prime or 180° meridian, the required longitude of the hashpoint can be calculated from the expression 0.000036° / cos(latitude).
*** Note that across the 180° Meridian, they points only mirror each other on the weekend, because of the 30° W rule.
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*** Note that across the 180° Meridian, they points only mirror each other on the weekend, because of the [[30W Time Zone Rule|30°W rule]].
* Go near the poles and be lucky
+
* Go near the poles and be lucky.
** in the 89 N or 89 S set of graticules, because they get closer together the further north they are the closer all points are to each other. When the latitude of the hashpoint is greater than 0.9984° the circle of uncertainty for two hashpoints will overlap.
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** At latitudes 89°N or 89°S, because graticules get narrower east-west the further north they are, hashpoints at all longitudes are closer to each other. When the latitude of the hashpoint is greater than 89.9984° the circles of uncertainty for two hashpoints will overlap.
* Get very very extremely lucky because of the 30° W rule.
+
* Get very very extremely lucky because of the 30°W rule.
 
** On weekdays hashpoints east and west of longitude 30°W are calculated separately, so may both be close to 30°W or 180°E/W.  However, pretty much all of these points will be in an ocean.
 
** On weekdays hashpoints east and west of longitude 30°W are calculated separately, so may both be close to 30°W or 180°E/W.  However, pretty much all of these points will be in an ocean.
  

Revision as of 07:37, 26 April 2016

TimeTravel.PNG

Template:Time-traveller

TimeTravel.PNG
This user earned the Time-traveller achievement
by reaching both the ({{{latitude}}}, {{{longitude}}}) and ({{{latitude2}}}, {{{longitude2}}}) geohashes at exactly {{{time}}} on {{{date}}}.

The achievement can be claimed if you venture to two or more geohashing locations on the same day and the same local time.

If you don't own a time-machine, you could ...

  • cross a time-zone border.
  • take advantage of the autumn daylight saving clocks change.
    • Geohashers nearer the equator are at a disadvantage because they have further to travel east or west.
    • Geohashers near longitude 0° or 180° might be lucky and not have to travel far at all.
  • Be in a mirror graticule and get extremely lucky.
    • Because graticules that touch across the equator or the prime meridian or the 180° meridian mirror each other, there is a very small chance, if you're standing on the border between them, that you could be in the circle of uncertainty for two hashpoints simultaneously.
      • For those graticules that touch across the equator, this happens if the latitude of the hashpoint is less than 0.000036°.
      • For those that touch across the prime or 180° meridian, the required longitude of the hashpoint can be calculated from the expression 0.000036° / cos(latitude).
      • Note that across the 180° Meridian, they points only mirror each other on the weekend, because of the 30°W rule.
  • Go near the poles and be lucky.
    • At latitudes 89°N or 89°S, because graticules get narrower east-west the further north they are, hashpoints at all longitudes are closer to each other. When the latitude of the hashpoint is greater than 89.9984° the circles of uncertainty for two hashpoints will overlap.
  • Get very very extremely lucky because of the 30°W rule.
    • On weekdays hashpoints east and west of longitude 30°W are calculated separately, so may both be close to 30°W or 180°E/W. However, pretty much all of these points will be in an ocean.

Of course, as usual, you need to upload photos of yourself containing the necessary proof.

Winners

Woodveil was at the 2009-03-08 33 -84 and 2009-03-08 33 -85 hashes at 12:39 local time.
B2c and Patrizius were at the 2013-10-27 47 13 and 2013-10-27 47 12 hashes at 02:09 local time. It was a DST time travel.
Micsnare and B2c were at the 2014-10-26 47 14 and 2014-10-26 47 13 hashes at 02:01 local time. It was a DST time travel. Again ;)

See also

Multihash -- reach multiple geohashes on one day