Schedule of Observations

Page 2 of 7
Celestial Observations made at the Mouth of the Marias River
2–10 June 1805
Day Type of Observation Number of Measurements and Description
02 Lunar distance from Spica 1 8, angle between the moon and Spica ˜ the time
02 Lunar distance from Spica 2 8, angle between the moon and Spica ˜ the time
03 Equal altitudes of the Sun AM 3, sun's altitude ˜ the time
03 Meridian (noon) altitude of the Sun 1, sun's altitude at its highest daily point in the sky
03 Equal altitudes of the Sun PM 3, sun's altitude ˜ the time
03 Lunar distance from the Sun 1 8, angle between the moon and sun ˜ the time
03 Lunar distance from the Sun 2 8, angle between the moon and sun ˜ the time
09 Magnetic declination using Sun AM 2, altitude and bearing of the sun ˜ the time
09 Equal altitudes of the Sun AM 3, sun's altitude ˜ the time
09 Meridian (noon) altitude of the Sun 1, sun's altitude at its highest daily point in the sky
09 Equal altitudes of the Sun PM 3, sun's altitude and bearing of the sun ˜ the time
09 Magnetic declination using Sun PM 6, angle between the moon and Aquila ˜ the time
09 Lunar distance from Aquila 6, angle between the moon and Aquila ˜ the time
09 Lunar distance from Spica 6, angle between the moon and Spica ˜ the time
9–10 Magnetic decllination using Polaris 3, bearing of Polaris ˜ the time
10 Meridian (noon) altitude of the Sun 1, sun's altitude at its highest daily point in the sky

The information derived from the captains' observations listed above is presented in the following sequence:

  1. Latitude
  2. Local Time
  3. Longitude
  4. Magnetic Declination (Variation of the Needle)