SJAA

Ephemeris

Comet Comments for December 1999

Don Machholz


Periodic Comet Machholz 2 remains in the southern evening sky. In late October Component D was found several arcminutes southwest of the primary component. As the comet brightens perhaps other parts will be found. In the Elements portion of this column I've included information for Comet LINEAR (C/1999 S4). As stated last month, it should brighten to unaided eye visibility next July in the northern polar region.

During the past month the LINEAR program in New Mexico found three new comets while the automated equipment at Lowell Observatory in Arizona (LONEOS) found three. The Catalina program found two, one being shared with LONEOS. The satellite SOHO found one new comet. Most notable is that Robert McNaught and M. Hartley discovered a comet (C/1999 T1) which is faint now but should be visible in amateurs' telescopes next summer. The Southern Hemisphere is favored until Jan. 2001, when the comet will move rapidly northward.

Comet Hunting Notes: We are nearly half-way through the year for the Wilson Comet Award. This award of $20,000 is divided among amateurs who find comets each year (June 12 to the next June 11). This "year", with seven months to go, only one person is eligible for the award. That is Steve Lynn of Australia who found a comet with handheld 10x50 binoculars on July 13. Obviously the automated search programs have taken away some of the potential amateur finds, with LINEAR's C/1998 T1 and C/1999 J3 being two recent examples.

Ephemeris

141P/Machholz 2 
Date(00UT) R.A. (2000) 	  Dec    El    Sky      Mag
11-08	18h32.9m	-11d50'	54d	E	10.9
11-13	18h47.8m	-11d46'	53d	E	10.1
11-18	19h03.8m	-11d39'	52d	E	9.4
11-23	19h20.8m	-11d33'	51d	E	8.7
11-28	19h39.0m	-11d27'	50d	E	8.2
12-03	19h58.5m	-11d25'	50d	E	7.7
12-08	20h19.5m	-11d29'	50d	E	7.4
12-13	20h42.5m	-11d41'	50d	E	7.2
12-18	21h08.2m	-12d04'	50d	E	7.1
12-23	21h37.7m	-12d38'	52d	E	7.2
12-28	22h12.2m	-13d21'	55d	E	7.4
01-02	22h53.4m	-14d07'	59d	E	7.8
01-07	23h42.1m	-14d41'	65d	E	8.2
01-12	00h37.6m	-14d41'	72d	E	8.7

Elements

Object:	P/Machholz 2
Peri. Date:		1999 12 09.2752
Peri. Dist (AU):	0.748905 AU
Arg/Peri (2000):	149.2991 deg.
Asc. Node (2000):	246.1434 deg.
Incl (2000):		012.8116 deg.
Eccen:			0.751075
Orbital Period:		5.22 years
Ref:			MPC 35815
Epoch:			1999 12 08
Absol. Mag/"n":		12.0/7.5 

Object:	LINEAR (1999 S4)
Peri. Date:		2000 07 26.3979
Peri. Dist (AU):	0.766182 AU
Arg/Peri (2000):	150.9998 deg.
Asc. Node (2000):	083.1500 deg.
Incl (2000):		149.3473 deg.
Eccen:			1.0
Orbital Period:		Long Period
Ref:			MPC 36213
Epoch:			2000 07 26
Absol. Mag/"n":		7.0/4.0
Don Machholz (530) 346-8963
Web Page: http://members.aol.com/cometcom/index.html
Don Machholz; last updated: October 04, 2007 Prev Next