On Fri, 11 Dec 1998 you wrote:
Hello,
First of all, the position of the sun at the equinoxes and solstices does
not form a cross in the sky, but is rather four points along a circle
(the circle being the sun's path through the Earth's sky, actually the
projection of Earth's orbit onto the sky). Likewise, our galaxy, the
Milky Way, appears as a circle in the sky. Since the Earth's orbit is
tilted with respect to the plane of the galaxy, the ecliptic, or path the
sun takes through the sky, intersects the galactic equator at two points.
This means that, twice each year, the sun does cross the galactic equator.
I looked in our astronomical almanac, which chronicals the position of
the sun (and all planets) throughout the year. According to the books,
the sun will be at 0.08 degrees galactic longitude, or 1/5 of the sun's
diameter, north of the galactic equator, so it appears that your source
is correct in saying that the sun crosses the galactic equator on the
solstice. Your source is also correct in saying that, due to the slow
wobble of Earth's rotation axis, this occurs every 26,000 years.
However, the sun was actually closer to the galactic equator at last
year's winnter solstice.
As to why this event has not been hyped, no astronomer that I know
attaches any greater significance to the location of the sun in the sky.
There is no scientific evidence whatsoever that the alignment (or
misalignment) of the sun with the galaxy will cause any sort of galactic
energy to infiltrate the Earth. It is still an interesting coincidence,
though, and thank you for pointing that out.
Sincerely,
Kurtis Williams
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