Lunar Distance As Seen In Toronto

Sunday July 14th was an excellent evening to measure a Lunar. The sky was perfectly clear and the Moon and Jupiter were clearly visible from my apartment balcony. This is generally not the case as there has been so much local construction in recent years.

The distance measured from the Moon_NearLimb to the centre of Jupiter = 16deg 1min

Sextant Index Error = 2min off

MoonHP = 55.7min

Calculation of Moon Semi Diameter at Earth’s Surface

Moon Semi Diameter + Augmentation = 15.3min

Lunar Distance_apparent = 16deg 1min + 2min (IE) + 15.3min (SDs) = 16deg 18.3min

MoonGP: GHA = 52deg 40.7min DEC = 21deg 57.6minS

JupiterGP: GHA = 69deg 55.4min DEC = 22deg 10.5minS

Calculation of Geo Centric Lunar Distance

Geo Centric Lunar Distance = 15deg 58.5min

Moon – Toronto/Hc/Az

Hc_moon = 19deg 54 min (Seen in Toronto)

Az_moon = 153deg 40.2min

Jupiter – Toronto/Hc/Az

Hc_jupiter = 23deg 32.6min (Seen in Toronto)

Az_jupiter = 170deg 25.5min

Ha_moon = Hc_moon + R – PA

Ha_moon = 19deg 54min + 2.7min – 52.6min = 19deg 4.1min

Ha_jupiter = Hc_jupiter + R = 23deg 32.6min + 2.2min = 23deg 34.8min

Lunar Distance_apparent

Lunar Distance_apparent_calculated = 16deg 14min

Lunar Distance_apparent_measured = 16deg 18.3min

Error = 4.3min

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