[AZ-Observing] Request for amateur astronomer observational data
- From: Jeff Hopkins <phxjeff@xxxxxxxxxxx>
- To: az-observing@xxxxxxxxxxxxx
- Date: Thu, 25 Jan 2007 10:42:30 -0700
The following from the LX200 list:
Subject: [LX200] Request for amateur astronomer observational data
Date: Mon, 22 Jan 2007 18:09:01 -0700
My name is Joseph C. Keller. I'm a 1977 cum laude graduate of
Harvard University, in Mathematics; and also, an amateur
astronomer. I'm seeking additional observational data which might
(or might not!) confirm certain theories of mechanics.
Request for observational data:
1. Micrometer distance vs. time for nearest-approaches of pairs of
Jovian moons. Much has been published about eclipses by Jupiter but
little about near-miss approaches of the moons themselves. I can
use this data for a new test of Newton's laws and Special Relativity.
This coming Sunday, Jan 28, 2007, at about 05:57 AM Mountain
Standard Time, about an hour, or more, before sunrise in the
Mountain Time Zone, Io & Europa will achieve such a minimum distance
(not very close, because one is in front & one behind Jupiter). (I
got this from the Sky&Telescope "chasing Jupiter's moons" site, and
confirmed it, to within a few minutes, two different ways by
measuring on a chart in the Astronomical Almanac.) This conjunction
also should be observable in most of the Pacific Time Zone because
Jupiter is high enough as a morning star now.
2. Observation of stellar occultations by Saturn's rings will
require a bigger telescope, maybe 18" (the size with which possibly
the most important professional ring-occultation observation ever,
was made in 1960 - it was 9th magnitude). The rings are getting
more edge-on (i.e., the occultation phenomena pass more quickly) and
Saturn is wandering toward sparser star fields. So unless one wants
to wait until Saturn approaches Sagittarius a decade from now, the
next four months give the best chance of a good occultation.
Occultations are least likely near the time when the planet is
stationary (May 2007) but such occultations proceed more slowly and
are likelier to yield new information. For the four occultation
reports I've seen, the closer to stationary Saturn was, the more
interesting the observations. I made a rough estimate that there
should be 10 occultations of stars of magnitude +11.5 or brighter
between now and stationarity in May.
The anomalous occultation findings that I found in my literature
search, appear below, and also in my post under the name "Joe
Keller" in the Special Relativity section of Dr. Van Flandern's
www.metaresearch.org messageboard, yesterday, Jan 21, 2007. Anyone
making any ring-occultation observations is invited to mail me a
report. Thank you.
*****
Mourao & Mourilhe (A F O'D Alexander, The Planet Saturn, 1962, pp.
442-443):
"As Saturn was then near a station, with apparent motion only 1" of
arc per hour...
"By 5h13m13s the immersion seemed to be complete...About 5h20m the
star seemed to 'beat', i.e. to move inside, then outside the ring, a
phenomenon repeated several times."
This 6.8 minutes of time, between immersion and the onset
of 'beating', amounts to 0.1" of movement of the ring edge, i.e., an
amplitude of 'beating' of 0.1", assuming the star moved just outside
the ring.
Mourao observed from Brazil, in 1960 with an 18-inch refractor, 650
power, with a 9th magnitude star and a clear, stable sky. In 1920,
from South Africa with a 6-inch refractor, 216 power, and a 7th
magnitude star, W Reid et al (Alexander, op. cit., pp. 346-347)(BAAJ
30:230) observed the light-spreading phenomenon at emersion from a
stellar occultation by Saturn, but during immersion into the ring,
Reid didn't see the 'beating', only fluctuation, a flicker, and
sudden extinction. However, Saturn was only about an hour from
opposition.
In 1917 (Alexander, op. cit., pp. 340-341), from Sussex with a 5-
inch refractor and 100 to 250 power, and a 7th magnitude star, J
Knight noted that
"...apart from isolated moments when the air was particularly
unsteady, [the occulted star] never seemed wholly to disappear."
When in the Cassini division, Knight thought the star's image looked
elongated. Saturn was about halfway between opposition and
quadrature. (The faster progression of occultation farther from
stationarity, might have merged the "beating" into a blur.)
The occultation of 28 Sgr in 1989 occurred when Saturn was near
opposition; neither 'beating' nor elongation were observed (J
Harrington et al, Icarus 103:235). A fault of the modern
occultation observations is that they tend to emphasize automated
data collection which would seem to miss such unexpected effects.
more details:
Request for observational data:
1. Micrometer separation distance, vs. time, for nearest-approaches
of pairs of Jupiter's Galilean moons (or Uranus' moons - see below).
Much has been published about eclipses by Jupiter but little about
near-miss approaches of the moons themselves. I can use this data
for a new test of Newton's laws and Special Relativity.
This coming Sunday, Jan 28, 2007, at about 05:57 AM Mountain Standard
Time, about an hour before sunrise in the Mountain Time Zone, Io &
Europa will achieve such a minimum distance (not very close, because
one is in front & one behind Jupiter). (I got this from the
Sky&Telescope "chasing Jupiter's moons" site, and confirmed it, to
within a few minutes of time, two different ways by measuring on a
chart in the Astronomical Almanac.) This conjunction also should be
observable in most of the Pacific Time Zone because Jupiter is high
enough as a morning star now.
For those with more powerful telescopes, who may wish to view an
evening star instead of a morning star: the equator of Uranus is
nearly edge-on to Earth during all of 2007. I would be able to use
separation vs. time data for conjunctions of pairs of Uranus' moons
also.
2. Observation of stellar occultations by Saturn's rings will
require a bigger telescope, maybe 18" (the size with which possibly
the most important professional ring-occultation observation ever,
was made in 1960 - it was 9th magnitude). The rings are getting more
edge-on (i.e., the occultation phenomena pass more quickly) and
Saturn is wandering toward sparser star fields. So unless one wants
to wait until Saturn approaches Sagittarius a decade from now, the
next four months give the best chance of a good occultation.
Saturn is stationary at about April 18 or 19. According to the
Millenium Star Atlas (one million stars to magnitude +11.5), Saturn
will be passing within roughly an arcminute of each of three
candidate stars of magnitude +10, 9 & 11 (east to west), near
stationarity. The brightest is about 300 arcsec closer to the
ecliptic than is the 6th magnitude reference star HD81361/SAO98561
(which is shown in Leo east of 8Leonis in both the Norton & Tirion
atlases); the other two stars are about 200 arcsec closer to the
ecliptic than is the reference star. The Sky Catalogue 2000.0 gives
the reference star at RA 9h25m32.4s, Dec +16deg35'08" for 2000AD; its
proper motion is negligible. It is type K0, 170pc distant. The
candidate stars are almost collinear, ranging from about
30arcminutes "SE by E", to 5 arcminutes "W by SW", of the reference
star.
Interpolating in the Astronomical Almanac, Saturn will cross the
reference star's longitude line, 181" south of it on March 30, and
302" south of it on May 10. That's 138" & 230" closer to the
ecliptic, resp. So of the six chances for an occultation, the best
are for the 10th & 11th mag. stars, in May. Because Saturn moves
only 134" per day on May 10, I can't measure the distances on the
page (1mm = 100 arcsec) accurately enough to predict the hour of
occultation with certainty. By measuring on the map, I estimate the
RA of the candidate stars as 9h27m21.5s, 9h26m29.6s, 9h25m11.7s (this
might be accurate to about one sec of RA). So the 11th mag. star
might be eclipsed by Saturn at 00:15 UT on May 8, and the 10th mag.
star at 21:40 UT on May 20, but these times are +/- two hours at best
(it seems that southern Europe will have the best chance to view
these).
Occultations are least likely near the time when the planet is
stationary (April 2007) but such occultations proceed more slowly and
are likelier to yield new information. For the four occultation
reports I've seen, the closer to stationary Saturn was, the more
interesting the observations. I made a rough estimate that there
should be 10 occultations of stars of magnitude +11.5 or brighter
between now and stationarity in April, 4 of which should be in the
Millenium Star Atlas, though I haven't found any yet in there, except
for the two likely occultations in May, above.
The anomalous occultation findings that I found in my literature
search, are in my post under the name "Joe Keller" in the Special
Relativity section of Dr. Van Flandern's www.metaresearch.org
messageboard, Jan 21, 2007. Anyone making any ring-occultation
observations is invited to mail me a report to:
Joseph C. Keller, M. D.
POB 9122
Ames, Iowa 50014 USA
Thank you.
--
Jeff Hopkins
HPO SOFT
Counting Photons
http://www.hposoft.com/Astro/astro.html
Hopkins Phoenix Observatory
7812 West Clayton Drive
Phoenix, Arizona 85033-2439 U.S.A.
www.hposoft.com
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