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Re: equinox
From: Fred Hebard
Date: 2004 Mar 21, 19:04 -0500
From: Fred Hebard
Date: 2004 Mar 21, 19:04 -0500
Here are the Sun's declination as reported in the Nautical Almanac versus time. Looks pretty linear to me. The discrepancy may lie elsewhere, such as the system of coordinates. When I said the time was exactly 6:48:00, I meant the calculation indicated 6:48:00, not 6:48:01 or 6:47:59. As both you and I said, it would be nice if an experienced astronomer would chime in here. Fred On Mar 21, 2004, at 6:35 PM, Zorbec Legras wrote: > ----- Original Message ----- > From: Gary Harkins> Date: Sun, 21 Mar 2004 14:06:46 EST >> >> Using the Nautical Almanac and interpolating between .8' South at >> 0600 utc >> and .2' North at 0700 utc the equinox calculates to occur at exactly >> 0648 utc. > > > A linear interpolation between two non linear values (even from the NA > page 63, uk release) is less accurate than a direct calculation made > by a qualified person. Your "exactly 0648 utc" seems to be a bad joke. > You're exactly early. > > The yearly Jean Meeus' sky calendar is made for astronomical > observations conducted by astronomers. > > Since 1896 was the the spring equinox never so early, your are eralier > than all spring equinoxes from 1896. But be patient, in 2008, > (2012,2016 ... 2048) it wil be earlier than this year even earlier > than yours. > > -- > ___________________________________________________________ > Sign-up for Ads Free at Mail.com > http://promo.mail.com/adsfreejump.htm >