New Comet: Ikeya-Zhang

The comet spotted last week in the constellation Cetus
should continue to brighten as it approaches the Sun. That's
the upshot of the orbital elements calculated on Monday by
Brian G. Marsden (Smithsonian Astrophysical
Observatory). Marsden's data suggest that Comet Ikeya-Zhang,
C/2002 C1, could become as bright as 4th magnitude by mid-March, but
it will be difficult to locate low in the western evening sky
after sunset. During the first week of April, the comet skirts
north of the Sun and enters the morning sky. Skywatchers in the
Northern Hemisphere will likely get their best views in late April,
when the comet makes a slow trek from Cassiopeia into Cepheus
and then Draco for those using binoculars and small telescopes.

The comet is already visible in 7x50 binoculars. Mike
Begbie of Harare, Zimbabwe, got his first look on Sunday evening,
February 3rd. He found it to be magnitude 8.2, noting that the
head (or coma) appeared "spherical, but surprisingly condensed."

According to Marsden's calculations, this comet
reaches its closest point to the Sun (perihelion) on
March 18th. At that time it will be midway between the orbits of
Venus and Mercury, at 0.51 astronomical unit (76 million
kilometers) from the Sun. Be sure to check the observing
section
of SkyandTelescope.com in the coming weeks for
further details.



Comet Ikeya-Zhang, C/2002 C1


Date

RA 2000

Dec.

Elong.

Mag.

Const.

0h UT

h   m

°   '

°

 

 

Feb 1

0 08.3

–17 51

45

8.9

Cet

Feb 3

0 11.6

–16 52

44

8.8

Cet

Feb 5

0 15.0

–15 51

43

8.6

Cet

Feb 7

0 18.4

–14 48

43

8.4

Cet

Feb 9

0 22.0

–13 43

42

8.2

Cet

Feb 11

0 25.7

–12 35

41

8.0

Cet

Feb 13

0 29.4

–11 24

40

7.8

Cet

Feb 15

0 33.2

–10 11

39

7.6

Cet

Feb 17

0 37.1

–08 54

38

7.4

Cet

Feb 19

0 41.1

–07 33

38

7.2

Cet

Feb 21

0 45.2

–06 09

37

7.0

Cet

Feb 23

0 49.2

–04 41

36

6.7

Cet

Feb 25

0 53.3

–03 09

36

6.5

Cet

Feb 27

0 57.4

–01 32

35

6.2

Cet

Mar 1

1 01.5

+00 10

34

6.0

Cet

The object's dual name recognizes the two comet
hunters who first found it on February 1st: Kaoru Ikeya of
Shizuoka prefecture, Japan, and Daqing Zhang in Henan
province, China. Zhang described the comet as a small, 8.5-
magnitude glow 3 arcminutes across in his 20-cm (8-inch)
reflector.

If the name "Ikeya" rings a bell, it should. Between
1963 and 1967, Kaoru Ikeya discovered or codiscovered five
comets. One of them, Comet Ikeya-Seki, was the famous
naked-eye Sungrazer of 1965. But little had been heard from
Ikeya (at least outside Japan) until he made his sixth comet
discovery last week. "He is the phoenix!" says
astrophotographer Shigemi Numazawa of Niigata, who adds
that Ikeya, now age 58, manages the Ikeya Optical Lab, a
supplier of telescope mirrors to Japan's discriminating
observers.