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Gentleman's Magazine 1742 p.132
St James's, March 20.
SIR,
SINCE my first Account of the Comet, which I sent you at
the Beginning of it's Appearance, I have had several
Opportunities of observing it (in the same Manner) again,
and have determin'ed it's Place amongst the fix'd Stars as
follows,
March 3, 11 H. 40 Min. P.M. I Observed it at A in
Lat. 78 Deg. 59 Min. North, and in Long. 19 Deg.
3 Min. of Pisces;
March 7, 10 H. 5 Min. P.M. I found it at B, it's
Lat. then was 76 Deg. 38 Min. North, Long. 20
Deg. 9 Min. of Taurus.
And March the 11th, 8 Hours 26 Min.
p.m. it appeared at C. Lat. 71 Deg. 8 Min.
North; Long. 8 Deg. 32 Min. of Gemini:
At A and B by reason of the Moon's more
powerful Reflection, the Tail was scarce perceptible, but
at C, it again appeared, tho' very faint, about 3
Deg. in Length. 'Tis in it's Ascent from the Sun, and was
in, or near its Perigeum, Feb 24th, about 5 Hours
before I saw it. Its Geocentric apparent Motion is
direct, but now it begins to incline to a Retrogradation,
and it's annual Parallax arising from the Earth's Motion (in
its Orbit) is very visible: The Mean ascending Node I make
in 8 Deg. 15 Min. of Capricorn, and the
Inclination of it's Way to the Plain of the Ecliptic, 79
D. 20 Min. but ye Equation of this Way, in the last
Intervals of Observation, more than the Arch of a Great
Circle, is 12 Min.
The proper Motion of this Comet in it's own Orbit is
contrary to the Order of Signs, and the Convex Part of it's
Trajectory in the present Transit, is towards the Earth: but
for want of an Observation, or two before the Perigeum I
find it will be very difficult to determine its true Course.
The Inclination of it's Path to the Plane of the Ecliptic
(or Heliocentric Latitude) I take to be much less than that
seen from the Earth, but the ascending Node, I judge not to
be far from that of the Siderial Way.
Mean Velocity of this Comet per Day, betwixt the First
and Second Observation, was 4 Deg. 53 Mon. 30 Sec.
between the 2d and 3d, 3 Deg. 10 Min.
and between the 3d and last, 1 Deg. 58 Min.
'tis now only to be seen thro' a Telescope.
Yours,
T. Wright.
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