Where was my Moon?
A few months ago I took a random picture of the Moon using my Theodolite app (on iPhone 7 Plus), which records the date, time, azimuth/horizontal angle, and altitude/elevation angle, and thought I would check it against a couple of sources:
Mooncalc.org data for this date, time, and location
Yup, it's where it should be -- I'm pointed low and to the right a bit.
Stellarium
Moon - Az/Alt: +275°09'58.1"/+29°52'47.0" (apparent)
The Altitude is within a fraction of a degree, the Azimuth of my device isn't terribly accurate (it wiggles around actively) because it's based partially on the magnetic reading -- so it's off by maybe 3-4 degrees.
To get an accurate heading we need to align to the stars and that's just not built-into phones yet. I'll be able to do it with my telescope pretty soon but I won't always have that with me -- but that should give me similar accuracy with heading measurements (if not better -- possibly down to a few arcseconds - but it depends upon the care with which I calibrate and align my telescope).
Mooncalc.org data for this date, time, and location
Yup, it's where it should be -- I'm pointed low and to the right a bit.
Stellarium
Moon - Az/Alt: +275°09'58.1"/+29°52'47.0" (apparent)
The Altitude is within a fraction of a degree, the Azimuth of my device isn't terribly accurate (it wiggles around actively) because it's based partially on the magnetic reading -- so it's off by maybe 3-4 degrees.
To get an accurate heading we need to align to the stars and that's just not built-into phones yet. I'll be able to do it with my telescope pretty soon but I won't always have that with me -- but that should give me similar accuracy with heading measurements (if not better -- possibly down to a few arcseconds - but it depends upon the care with which I calibrate and align my telescope).
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