C/2002 T7 LINEAR

The Great Binocular Comet of 2004 no2
Closest to Sun on 22 April 2004 at 0.62AU
Closest to Earth on 19 May 2004 at 0.26AU
Maximum magnitude 2.5 in May 2004

C/2002 T7 LINEAR was discovered on October 14, 2002 by the Lincoln laboratory Near Earth Asteroid Research
project at a distance of 6.9 AU from the Sun. Northern hemisphere observers were favored prior to perihelion.
It was lost into evening twilight by the start of March 2004 as a 6th magnitude object in Pegasus.

By mid April 2004, LINEAR was recovered low in the morning sky from both hemispheres, shining at 4th magnitude.
It was closest to the Sun on April 23 at 0.61 AU (92 million kms) when situated in Pisces.

The comet was lost to the Northern Hemisphere by the start of May 2004. By this time, it was well placed for
Southern Hemisphere observers at 20 degrees altitude by the start of twilight. Moonlight interfered from May 4th.

This photo was taken on May 14, 2004 at 20:00 UT.
C/2002 T7 has an ion tail stretching over 20 degrees long, between stars Upsilon and Tau Ceti. Beta Ceti is at far left.
Due to moonlight, I was only able to observe 4 degrees with the unaided eye.

LINEAR approached solar conjunction on May 18 at which time it rapidly moved from morning to evening skies,
joining C/2001 Q4 NEAT for a double comet show.

Closest approach to the Earth occurred on May 19, 2004 at 0.27 AU (40 million kms).
At this time, the comet achieved a peak brightness of magnitude 2.5
and appeared prominent to the unaided eye in the constellation of Eridanus.



By the evening of May 20, the comet was visible to the unaided eye in the constellation of Lepus.
The ion tail is seen stretching towards Columba, whilst a dust trail is seen towards the lower left.
Sirius in Canis Major is at top right

Moonlight interfered from May 23rd 2004.

This appears to be LINEAR's first and only passage through the inner solar system.

My observations in ICQ format below

2002T7 2003 11 14.56 S 10.0 TK 28 T10 133 1.0 7 ICQ nn MAT08
2002T7 2004 04 16.80 !B 4.3 TK 5 B 7 &5 8 2.5 256 ICQ nn MAT08
2002T7 2004 05 07.83 I 3.6 TK 0.7E 1 6 ICQ nn MAT08
2002T7 2004 05 14.83 I 2.6:TK 0.7E 1 25 6 >4.0 213 ICQ nn MAT08
2002T7 2004 05 18.38 I 2.5 TK 0.7E 1 30 5 >2.0 162 ICQ nn MAT08
2002T7 2004 05 19.38 I 2.8 TK 0.7E 1 30 5 ICQ nn MAT08
2002T7 2004 05 24.40 I 4.0 TK 5 B 1 20 4 ICQ nn MAT08


2002T7 040507.83 Moonlight 88%, iota & eta Ceti used as comparisons. [MAT08]
2002T7 040514.83 13 degrees above morning horizon. Correction for atmospheric extinction not applied. Moonlight 17%. A
spectacular view through 25x100mm B, the coma lacks a stellar nucleus as evident in 2001 Q4. [MAT08]
2002T7 040518.38 15 degrees above evening horizon. Correction for atmospheric extinction not applied. Tail appears to
have lost intensity since last observation on May 14.83 UT [MAT08]
2002T7 040519.38 hazy conditions. Similar to beta Lepus in magnitude. [MAT08]