C/2000 WM1 LINEAR
The Great Southern Binocular Comet of 2002
Closest to Earth on 2 Dec 2001 at 0.31AU
Closest to Sun on 22 Jan 2002 at 0.55AU
Maximum magnitude 2.5 in late January 2002
Orbital period: N/A parabolic
This comet experienced a spectacular outburst at perihelion,
in late January 2002.
2002 Jan 30.78 UT.
C11 f/6 + Starlight Express MX7c imager
This image has been digitally developed to reveal multiple jets, reminiscent of
a water sprinkler
Comet C/2000 WM1 LINEAR was closest to Earth in early December 2001.
At the time, it was located in the evening sky in Cetus and shone at magnitude 5.8.
Little did it indicate what was to follow.
By January 22, 2002, the comet reached solar conjunction and
was then moving into the morning sky in Telescopium.
Then, on the morning of 2002 Jan 30 (Jan 29.78 UT),
Comet LINEAR underwent a spectacular outburst.
It appeared star-like to the eye at magnitude 3.0, in bright moonlight.
Through 25x100mm
binoculars, the comet revealed 2 bright jets emanating from opposite poles of the
star-like nucleus.
The brighter jet was 60" long in PA 250
while the fainter jet was 25" long in PA 120.
This feature reminded me of classical comet drawings of the past.
By the following morning, 2002 January 30.78UT, its visual appearance had changed considerably.
The 2 jets seen on the previous morning had now travelled down the length of the comet,
forming a "dark lane".
The dark lane is caused by a "nuclear shadow" where dust is prevented from
getting in behind the comet .
A parabolic hood was also evident.
Below:
Larsen-Sekanina filter processed images of C/2000 WM1 LINEAR showing the
evolution of the outburst.
The parabolic hood gave way to a more triangular appearance of the head in the
space of 5 days.
2002 Jan 30.78 UT
2002 Jan 31.78 UT
2002 Feb 4.78 UT
2002 Jan 31.78 UT
50mm lens, 30 second exposure, fuji 800 ASA.
Sagittarius " the teapot" is to the left. Corona Australis is at
centre.
Bright moonlight makes the background
sky appear blue. Naked eye visual estimate = 3.0
2002 Feb 4.78 UT
Naked eye Visual estimate = 3.8. You can see the dust tail developing nicely.
Moonlight interference
2002 Feb 5.78 UT
200mm lens, 2 minute exposure, fuji 800 ASA.cropped
2002 Feb 5.78 UT
2002 Feb 6.78 UT
200mm lens, 2 minute exposure, fuji 800 ASA.
Dust tail length is 2 degrees. Naked eye visual estimate = 4.3
Beta 1 and 2 Sgr are stars at top of frame.
2002 Feb 7.78 UT
Note Corona Australis, Alpha and Beta 1,2 Sagittarii
2002 Feb 12.78UT.
LINEAR C/2000 WM1 and Corona Australis.
Moonlight no longer interfered but the comet had faded to magnitude 4.5
The dust tail is about 4 degrees long, stretching towards Corona Australis.
2002 Feb 21.78UT.
comet C/2000 WM1 is located near the Teapot handle asterism in Sagittarius.(top
left)
Note globular cluster M55 is to the lower right
Comet has faded to magnitude 6.1
See below a light curve based on my personal observations.
Pre-perihelion calculated magnitude parameters. Ho=8, n=4 (red curve)
Post perihelion calculated magnitude parameters. Ho=6.4, n=6 (purple curve)
Orbit of comet LINEAR on the date of outburst.
The comet was receding from both Sun and Earth.
Note that the orbit intersects the Earths orbit.
Had the comet arrived 2 months later, we would have had an exceptional view!
below are my observations in ICQ format
2000WM1 2001 11 12.60 B 8.3 TJ 10 B 25 4.0 5 ICQ nn MAT08
2000WM1 2001 11 15.60 B 8.1 TJ 10 B 25 4.5 6 ICQ nn MAT08
2000WM1 2001 11 20.55 B 6.7 TT 5 B 7 10.0 6 ICQ nn MAT08
2000WM1 2001 12 03.49 B 5.8 TT 5 B 7 12.0 6 >1 33 ICQ nn MAT08
2000WM1 2001 12 04.48 B 5.7 TT 5 B 7 12.0 6 >1 33 ICQ nn MAT08
2000WM1 2001 12 06.51 B 5.8 TT 5 B 7 11.0 6 >1 30 ICQ nn MAT08
2000WM1 2001 12 09.51 B 5.8 TT 5 B 7 10.0 6 >1 50 ICQ nn MAT08
2000WM1 2001 12 11.57 B 5.9 TT 5 B 7 9.0 6 >0.75 45 ICQ nn MAT08
2000WM1 2001 12 12.56 B 5.7 TT 5 B 7 8.0 6 >0.5 50 ICQ nn MAT08
2000WM1 2001 12 15.52 B 5.8 TT 5 B 7 8.0 6 >1 60 ICQ nn MAT08
2000WM1 2001 12 16.54 B 5.9 TT 5 B 7 8.0 6 1 65 ICQ nn MAT08
2000WM1 2001 12 17.54 B 6.0 TT 5 B 7 7.0 6 >1 60 ICQ nn MAT08
2000WM1 2001 12 20.58 B 6.1 TT 5 B 7 6.0 6 ICQ nn MAT08
2000WM1 2001 12 21.52 B 6.1 TT 5 B 7 5.0 6 ICQ nn MAT08
2000WM1 2001 12 25.48 B 6.3 TT 5 B 7 4.0 7 ICQ nn MAT08
2000WM1 2001 12 27.48 B 6.2 TT 5 B 7 4.0 7 ICQ nn MAT08
2000WM1 2002 01 04.54 B 6.1 TT 5 B 7 4.0 7 >1.0 110 ICQ nn MAT
2000WM1 2002 01 09.51 B 6.1 TT 5 B 7 3.0 7 >1.0 129 ICQ nn MAT
2000WM1 2002 01 16.51 B 6.0 TT 5 B 7 3.0 7 >2.0 ICQ nn MAT
2000WM1 2002 01 29.78 B 3.0 TT NE 9 ICQ nn MAT
2000WM1 2002 01 30.78 B 2.9 TT NE 8/ ICQ nn MAT
2000WM1 2002 01 31.78 !B 3.0 TT NE 8 ICQ nn MAT
2000WM1 2002 02 04.78 !B 3.8 TT NE 7 ICQ nn MAT
2000WM1 2002 02 05.78 !B 4.0 TT NE 7 ICQ nn MAT
2000WM1 2002 02 06.78 !B 4.3 TT NE 7 ICQ nn MAT
2000WM1 2002 02 07.78 !B 4.3 TT NE 7 ICQ nn MAT
2000WM1 2002 02 10.78 !B 4.4 TT NE 7 >2 222 ICQ nn MAT
2000WM1 2002 02 12.78 !B 4.5 TT NE 7 ICQ nn MAT
2000WM1 2002 02 15.77 B 5.0 TT 5 B 7 4.0 6 >3 ICQ nn MAT
2000WM1 2002 02 16.77 B 5.2 TT 5 B 7 4.0 6 >4 225 ICQ nn MAT
2000WM1 2002 02 21.78 B 6.1 TT 5 B 7 4.0 6 >1 240 ICQ nn MAT
2000WM1 2002 03 13.73 B 8.1 TT 5 B 7 2.0 5 >1 230 ICQ nn MAT
2000WM1 2002 03 14.75 B 8.1 TT 10 B 25 3.0 5 >1.3 232 ICQ nn MAT
2000WM1 1011112.60 m2~11th magnitude [MAT]
2000WM1 1011120.55 in 25x100mm B, antitail length 15' in PA 330. [MAT]
2000WM1 1011203.49 m2~9th magnitude. [MAT]
2000WM1 1011221.52 moonlight 37% [MAT]
2000WM1 1011225.48 moonlight 74% [MAT]
2000WM1 1011227.48 moonlight 90% [MAT] 2000WM1 1020109.51 In 25x100mm B, ion
tail >1.5 deg has increased in intensity. [MAT]
2000WM1 1020129.78 Appearing starlike to the eye but 25x100mm B reveal 2 jets,
the brighter jet is [MAT]
2000WM1 1020129.78 60" long in PA 250 while the fainter jet is 25" long in PA
120. Moonlight 99%. [MAT]
2000WM1 1020130.78 In 25x100mm B, jets now developed into classic parabola
separated by a "dark [MAT]
2000WM1 1020130.78 lane. Moonlight 95%. [MAT]
2000WM1 1020131.78 In 25x100mm B, coma diameter 4.0' jets now developed into
parabolic dust hood [MAT]
2000WM1 1020131.78 11' long in PA 200, tail > 2 deg. Moonlight 89%. [MAT]
2000WM1 1020204.78 In 7x50 B, V shaped coma of diameter 4.0' and now well
developed dust tail [MAT]
2000WM1 1020204.78 > 2 deg in PA 215. Moonlight 47%. [MAT]
2000WM1 1020205.78 Moonlight 37% [MAT]
2000WM1 1020206.78 In 7x50mm B, coma diameter 4', dust tail > 2.5 deg in PA 220.
Moonlight 27%. [MAT]
2000WM1 1020207.78 In 7x50mm B, coma diameter 4', dust tail > 3 deg. Moonlight
18%. [MAT]
2000WM1 1020210.78 In 7x50mm B, dust tail > 3.3 deg in PA 222. Moonless
observation. [MAT]