You are here

Comments on Solar Time


The motion of the Sun is an illusion: it is the Earth that is moving, not the Sun. The Earth rotates once a day, which makes the Sun appear to rise in the east and set in the west. The Earth revolves around the Sun once a year, which causes the Sun to appear to move in front of the background of stars, so that the stars gradually change over the year.

Working at

Stephanie don't tell me Earth also isn't a disk??

Should read B=360/365(d-81), at the time of this comment it erroneously reads B=360/365(d)(-81) which makes the -81 a nonsensical scalar of the Day_of_Year rather than a translation term to convert Day_of_Year from a January 1 reference point to a fall equinox reference point.

It is fixed. The error crept in recently when I recently reformatted the equation. Thanks very much for letting me know.

"By definition, the Hour Angle is 0° at solar noon" .

Setting (longitude = timezone = day of year = 0) and (local time = 12:00) gives Hour Angle = 179.19 in the online calculator on this page.

Shouldn't this value be approaching zero for these inputs?


For me the paragraph named "Local Solar Time (LST) and Local Time (LT)" is unclear: it defines LST, but does not LT, so the text and formulas following it are fuzzy.
Moreover, it seems to me from the text and formulas following that paragraph that the time "when the sun is highest in the sky" is more LT than LST. Am I right?
Please, consider revising the paragraph "Local Solar Time (LST) and Local Time (LT)" giving a clear definition of both times, so that one can understand the text and formulas below it.
Thanks a lot!

Primary tabs