BAA Comet Section : Comets discovered in 2005

Updated 2008 October 2


  • 1981 W1 (SOLWIND)
  • 1983 N2 (SOLWIND)
  • 1984 Q1 (SOLWIND)
  • 1984 R1 (SOLWIND)
  • 1995 O1 (Hale-Bopp)
  • 1996 N3 (SOHO)
  • 1996 V2 (SOHO)
  • 1997 B4 (SOHO)
  • 1997 E2 (SOHO)
  • 1997 J5 (SOHO)
  • 1997 V7 (SOHO)
  • 1998 U7 (SOHO)
  • 2000 QJ46 (P/LINEAR)
  • 2000 S6 (SOHO)
  • 2000 V4 (SOHO)
  • 2001 Q9 (SOHO)
  • 2001 S3 (SOHO)
  • 2002 EX12 (169P/NEAT)
  • 2005 A1 (LINEAR)
  • 2005 A2 (SOHO)
  • 2005 A3 (SOHO)
  • 2005 A4 (SOHO)
  • 2005 A5 (SOHO)
  • A/2005 AB [Catalina]
  • 2005 B1 (Christensen)
  • 2005 B2 (SOHO)
  • 2005 B3 (SOHO)
  • 2005 B4 (SOHO)
  • A/2005 BY1 [Steward]
  • 2005 C1 (SOHO)
  • 2005 C2 (SOHO)
  • 2005 C3 (SOHO)
  • 2005 C4 (SOHO)
  • 2005 D1 (SOHO)
  • 2005 E1 (Tubbiolo)
  • 2005 E2 (McNaught)
  • 2005 E3 (SOHO)
  • 2005 E4 (SOHO)
  • 2005 E5 (SOHO)
  • 2005 E6 (SOHO)
  • 2005 E7 (SOHO)
  • 2005 E8 (SOHO)
  • 2005 E9 (SOHO)
  • A/2005 EO70 [LINEAR]
  • A/2005 EW169 [Mt Lemon]
  • 2005 EL173 (LONEOS)
  • 2005 F1 (SOHO)
  • 2005 F2 (SOHO)
  • 2005 F3 (SOHO)
  • 2005 F4 (SOHO)
  • 2005 F5 (SOHO)
  • 2005 G1 (LINEAR)
  • 2005 G2 (SOHO)
  • 2005 G3 (SOHO)
  • 2005 G4 (SOHO)
  • 2005 G5 (SOHO)
  • 2005 G6 (SOHO)
  • 2005 G7 (SOHO)
  • 2005 GF8 (LONEOS)
  • A/2005 GF81 [Mt Lemon]
  • 2005 H1 (LINEAR)
  • 2005 H2 (SOHO)
  • 2005 H3 (SOHO)
  • 2005 H4 (SOHO)
  • 2005 H5 (SOHO)
  • 2005 H6 (SOHO)
  • 2005 H7 (SOHO)
  • 2005 H8 (SOHO)
  • 2005 H9 (SOHO)
  • A/2005 HL3 [Siding Spring]
  • A/2005 HC4 [LONEOS]
  • 2005 J1 (P/McNaught)
  • 2005 J2 (Catalina)
  • 2005 J3 (SOHO)
  • 2005 J4 (SOHO)
  • 2005 J5 (SOHO)
  • 2005 J6 (SOHO)
  • 2005 J7 (SOHO)
  • 2005 J8 (SOHO)
  • 2005 J9 (SOHO)
  • 2005 J10 (SOHO)
  • 2005 J11 (SOHO)
  • 2005 J12 (SOHO)
  • 2005 JN (Spacewatch)
  • 2005 JQ5 (P/Catalina)
  • 2005 JD108 (P/Catalina-NEAT)
  • 2005 JY126 (P/Catalina)
  • A/2005 JM3 [Catalina]
  • 2005 K1 (P/Skiff)
  • 2005 K2 (LINEAR)
  • 2005 K3 (P/McNaught)
  • 2005 K4 (SOHO)
  • 2005 K5 (SOHO)
  • 2005 K6 (SOHO)
  • 2005 K7 (SOHO)
  • 2005 K8 (SOHO)
  • 2005 K9 (SOHO)
  • 2005 K10 (SOHO)
  • 2005 L1 (P/McNaught)
  • 2005 L2 (McNaught)
  • 2005 L3 (McNaught)
  • 2005 L4 (P/Christensen)
  • 2005 L5 (SOHO)
  • 2005 L6 (SOHO)
  • 2005 L7 (SOHO)
  • 2005 L8 (SOHO)
  • 2005 L9 (SOHO)
  • 2005 L10 (SOHO)
  • 2005 L11 (SOHO)
  • 2005 L12 (SOHO)
  • 2005 L13 (SOHO)
  • 2005 L14 (SOHO)
  • 2005 L15 (SOHO)
  • 2005 M1 (170P/Christensen)
  • 2005 M2 (SOHO)
  • 2005 M3 (SOHO)
  • 2005 M4 (SOHO)
  • 2005 M5 (SOHO)
  • 2005 M6 (SOHO)
  • 2005 M7 (SOHO)
  • 2005 M8 (SOHO)
  • 2005 M9 (SOHO)
  • 2005 M10 (SOHO)
  • A/2005 MW1 [Siding Spring]
  • A/2005 MW9 [Mt Lemon]
  • 2005 N1 (Juels-Holvorcem)
  • 2005 N2 (168P/Hergenrother)
  • 2005 N3 (Larson)
  • 2005 N4 (Catalina)
  • 2005 N5 (Catalina)
  • 2005 N6 (SOHO)
  • 2005 N7 (SOHO)
  • 2005 N8 (SOHO)
  • 2005 N9 (SOHO)
  • 2005 N10 (SOHO)
  • A/2005 NA56 [Mt Lemon]
  • A/2005 NP82 [Siding Spring]
  • 2005 O1 (NEAT)
  • 2005 O2 (Christensen)
  • 2005 O3 (SOHO)
  • 2005 O4 (SOHO)
  • 2005 O5 (SOHO)
  • 2005 O6 (SOHO)
  • A/2005 OE [Catalina]
  • 2005 P1 (SOHO)
  • 2005 P2 (SOHO)
  • 2005 P3 (SWAN)
  • 2005 P4 (SOHO)
  • 2005 P5 (SOHO)
  • 2005 P6 (SOHO)
  • 2005 Q1 (LINEAR)
  • 2005 Q2 (SOHO)
  • 2005 Q3 (SOHO)
  • 2005 Q4 (P/LINEAR)
  • 2005 Q5 (SOHO)
  • 2005 Q6 (SOHO)
  • 2005 Q7 (SOHO)
  • 2005 Q8 (SOHO)
  • 2005 Q9 (SOHO)
  • 2005 Q10 (SOHO)
  • 2005 R1 (P/NEAT)
  • 2005 R2 (P/Van Ness)
  • 2005 R3 (171P/Spahr)
  • 2005 R4 (LINEAR)
  • 2005 R5 (SOHO)
  • 2005 R6 (SOHO)
  • 2005 R7 (SOHO)
  • 2005 S1 (SOHO)
  • 2005 S2 (Skiff)
  • 2005 S3 (P/Read)
  • 2005 S4 (McNaught)
  • 2005 S5 (SOHO)
  • 2005 S6 (SOHO)
  • 2005 S7 (SOHO)
  • 2005 S8 (SOHO)
  • 2005 S9 (SOHO)
  • 2005 S10 (SOHO)
  • 2005 S11 (SOHO)
  • 2005 S12 (SOHO)
  • 2005 S13 (SOHO)
  • 2005 SB216 (P/LONEOS)
  • 2005 SD [A/LINEAR]
  • A/2005 SB223 [Siding Spring]
  • 2005 T1 (173P/Mueller)
  • 2005 T2 (P/Christensen)
  • 2005 T3 (P/Read)
  • 2005 T4 (P/SWAN)
  • 2005 T5 (P/Broughton)
  • 2005 T6 (SOHO)
  • 2005 T7 (SOHO)
  • 2005 T8 (SOHO)
  • 2005 T9 (SOHO)
  • 2005 T10 (SOHO)
  • 2005 T11 (SOHO)
  • A/2005 TC [Mt Lemon]
  • A/2005 TF50 [Steward]
  • A/2005 TJ50 [Steward]
  • 2005 U1 (P/Read)
  • 2005 U2 (SOHO)
  • 2005 U3 (SOHO)
  • 2005 U4 (SOHO)
  • 2005 U5 (SOHO)
  • 2005 U6 (SOHO)
  • 2005 U7 (SOHO)
  • 2005 U8 (SOHO)
  • A/2005 UJ159 [NEAT]
  • A/2005 UN398 []
  • 2005 V1 (P/Bernardi)
  • 2005 V2 (SOHO)
  • 2005 V3 (SOHO)
  • 2005 V4 (SOHO)
  • 2005 V5 (SOHO)
  • 2005 V6 (SOHO)
  • 2005 V7 (SOHO)
  • 2005 V8 (SOHO)
  • 2005 V9 (SOHO)
  • A/2005 VD [Mt Lemon]
  • A/2005 VH1 [Steward]
  • A/2005 VX3 [Mt Lemon]
  • 2005 W1 (SOHO)
  • 2005 W2 (Christensen)
  • 2005 W3 (P/Kowalski)
  • 2005 W4 (SOHO)
  • 2005 W5 (SOHO)
  • 2005 W6 (SOHO)
  • 2005 W7 (SOHO)
  • 2005 W8 (SOHO)
  • 2005 W9 (SOHO)
  • 2005 W10 (SOHO)
  • 2005 W11 (SOHO)
  • 2005 W12 (SOHO)
  • 2005 W13 (SOHO)
  • 2005 W14 (SOHO)
  • 2005 W15 (SOHO)
  • 2005 W16 (SOHO)
  • 2005 W17 (SOHO)
  • A/2005 WY3 [Spacewatch]
  • 2005 X1 (Beshore)
  • 2005 X2 (SOHO)
  • 2005 X3 (SOHO)
  • 2005 X4 (SOHO)
  • 2005 X5 (SOHO)
  • 2005 X6 (SOHO)
  • 2005 X7 (SOHO)
  • 2005 X8 (SOHO)
  • 2005 X9 (SOHO)
  • 2005 XA54 (P/LONEOS-Hill)
  • 2005 Y1 (SOHO)
  • 2005 Y2 (McNaught)
  • 2005 Y3 (SOHO)
  • 2005 Y4 (SOHO)
  • 2005 Y5 (SOHO)
  • 2005 Y6 (SOHO)
  • 2005 Y7 (SOHO)
  • 2005 Y8 (SOHO)
  • 2005 Y9 (SOHO)
  • 2005 Y10 (SOHO)
  • 2005 YW (LINEAR)
  • 2005 YQ127 (P/LINEAR)

  • When observing a comet please try to forget how bright you think the comet should be, what it was when you last viewed it, what other observers think it is or what the ephemeris says it should be.

    The equations for the light curves of comets that are currently visible use only the raw observations and should give a reasonable prediction for the current brightness. If the comet has not yet been observed or has gone from view a correction for aperture is included, so that telescopic observers should expect the comet to be fainter than given by the equation. The correction is about 0.033 per centimetre. Values for the r parameter given in square brackets [ ] are assumed. The form of the light curve is either the standard m = H0 + 5 log d + K0 log r or the linear brightening m = H0 + 5 log d + L0 abs(t - T + D0) where T is the date of perihelion, t the present and D0 an offset, if L0 is +ve the comet brightens towards perihelion and if D0 is +ve the comet is brightest prior to perihelion.

    Observations of new comets are given in ICQ format. More recent ones may be available in TA format from the main page.

    Full details of recently discovered objects will not appear until they are available on the CBAT web pages, which is usually a fortnight after the publication of the IAUC.


    Meyer Group SOHO comets
    1996 N3 SOHO(IAUC )
    2005 B4 SOHO(IAUC 8488, 2005 February 27)
    2005 C1 SOHO(IAUC 8498, 2005 March 24)
    2005 H2 SOHO(IAUC )
    2005 H9 SOHO(IAUC )
    2005 K4 SOHO(IAUC )
    2005 K9 SOHO(IAUC )
    2005 O5 SOHO(IAUC )
    2005 Q2 SOHO(IAUC )
    2005 Q8 SOHO(IAUC )
    2005 T9 SOHO(IAUC )
    2005 W9 SOHO(IAUC )
    2005 W11 SOHO(IAUC )
    2005 Y8 SOHO(IAUC )
    were discovered with the SOHO LASCO coronographs and have not been observed elsewhere. They were sungrazing comets of the Meyer group. For further information on the discovery of these objects see this year's SOHO discoveries.
    Kracht Group SOHO comets
    2005 W4 (SOHO)(IAUC 8638, 2005 December 4)
    was discovered with the SOHO LASCO coronographs and has not been observed elsewhere. It was a sungrazing comet of the Kracht group.

    Brian Marsden comments on MPEC 2005-X14 [2005 December 3]

    It seems likely that the Kracht-group comet C/2005 W4 is a return of C/2000 O3 (cf. MPEC 2000-Q09), a suggestion made by S. Hoenig before the observations above were available. The orbital linkage utilizes just the C2 observations (those from July 30.89596 onward in the case of C/2000 O3); although only the first three C/2005 W4 observations were obtained with C2, the residuals of the C3 observations are not systematically displaced.
    This orbit gives the comet a period of 5.3 years and perihelion at 0.054 AU. Jonathan Shanklin discovered the comet in 2000, and Bo Zhou made the recovery.

    For further information on the discovery of these objects see this year's SOHO discoveries.


    Marsden Group SOHO comets
    1996 V2 (SOHO)(IAUC 8499, 2005 March 27)
    2005 E4 (SOHO)(IAUC 8494, 2005 March 16)
    2005 G2 SOHO(IAUC )
    2005 W1 SOHO(IAUC )
    2005 W5 SOHO(IAUC 8638, 2005 December 4)
    were discovered with the SOHO LASCO coronographs and have not been observed elsewhere. They were sungrazing comets of the Marsden group.

    Although Marsden gives a parabolic orbit for C/2005 E4 on MPEC 2005-E87 [2005 March 15] he also notes:

    Despite the parabolic orbit solutions, it seems quite likely that C/2005 E4 is identical with C/1999 N5 (cf. MPEC 2002-F03). He gives a tentative linkage of just the C2 observations (which in the case of C/1999 N5 are those made on July 11.56347 UT and earlier), which has a period of 5.66 years and perihelion at 0.0492 AU.

    In support of the proposed identification, as well as of the proposed identification C/1999 J6 = 2004 V9 (cf. MPEC 2004-X73), the respective orbits have been run back one further revolution (to Epoch 1993 Nov. 29.0 TT). The tabulation below shows in particular the remarkable agreement of the perihelion times T (as well as of the perihelion distances q). Indeed, this circumstance shows, not only that C/1999 J6 and C/1999 N5 probably separated from each other around that perihelion passage (the remaining slight discordances being understandable on account of the poor quality of even the C2 observations), but also that the splitting scenario discussed here and on MPEC 2004-X73 is in fact likely to be essentially correct. The comets passed 1.3-1.4 AU from Jupiter in May 1996.

    Orbital elements:
    Comet            T              q       e       Peri.    Node     Incl.     C
    CJ99J060   1993 Nov.  22.66   0.0515   0.9834   21.01    83.36    28.34     X
    CJ99N050   1993 Nov.  20.98   0.0515   0.9838   21.17    83.10    28.10     X
    
    Three further faint members of this related group of comets (C/1999 P6, C/1999 P8, C/1999 P9: cf. MPEC 2002-F43) were observed during 1999 Aug. 5-15; and C/1999 U2 (MPEC 1999-U29), one of the brighter original prototypes (with C/1999 J6, cf. MPEC 2002-C28), was observed on 1999 Oct. 25. Although neither the chance of survival nor the specific manner in which these members evolved from the original parent body is known, it seems likely that C/1999 U2, at least, will be reobserved on its next return to perihelion, presumably during the next few months. If this comet indeed separated from C/1999 J6 and C/1999 N5 near perihelion around 1993 Nov. 20-22, it should have a period (now) of 5.95 years (i.e., near 2:1 mean-motion resonance with Jupiter) and return to perihelion within a few days of 2005 Oct. 8.
    Rainer Kracht notes that 1996 V2 may be an earlier return of 2002 V5. The Marsden-group comet C/2005 G2 presumably has an orbital period of 5-6 years, but it appears not to be a return of one of C/1999 P6, 1999 P8, 1999 P9 or 1999 U2 (MPEC 2002-F43, 1999-U29). The C2 data for C/2005 G2 do fit well with the observations of C/1999 P8 (all being C2), but the current C3 data show a systematic R.A. departure increasing from 1 to 4 arcmin. [MPEC 2005-G94, 2005 April 15]

    Brian Marsden further predicts on MPEC 2005-H24 [2005 April 22]

    Further to the statement at the end of MPEC 2005-G94, it should be noted that the best fit of C/2005 G2 to earlier comets is to C/1999 N5, the resulting orbital solution uses C2 observations alone, although the C3 observations do not show any systematic departure above 1 arcmin.

    On MPEC 2005-E87, C/1999 N5 was linked (with comparable residuals) to C/2005 E4. It therefore seems plausible that C/2005 G2 separated from C/2005 E4 around the time of the C/1999 N5 perihelion passage, in much the same manner that C/1999 N5 may have separated from C/1999 J6 around a mutual Nov. 1993 perihelion passage. If C/1999 P6 (cf. MPEC 2002-F43) also separated at that 1993 perihelion passage, it should return (if it has survived) within a few days of 2005 Apr. 28 (likewise for C/1999 P8 and P9 around 2005 May 18).

    Karl Battams has put together a probable family tree for the fragments.

    Marsden group comet 2005 W1 has been linked to 2000 C4. Brian Marsden notes on MPEC 2005-W07 [2005 November 18]

    It seems probable that this comet is identical with C/2000 C4 (MPEC 2000-C52; alternative direct orbit chosen on IAUC 7832 and MPC 44860), although it is conceivably identical with C/2000 C3 or C/2000 C7, which appeared around the same time (and, if they still exist, are also presumably about to return).
    The linked orbit has a period of 5.78 years, with aphelion beyond the orbit of Jupiter.

    Brian Marsden notes on MPEC 2005-X14 [2005 December 3]

    Comet C/2005 W5 has not been satisfactorily linked to a Marsden-group candidate at its previous perihelion passage, although potential fits to the various 1999 members seem preferable to those involving the comets of Feb. 2000 (cf. MPEC 2005-W07).
    He further notes on MPEC 2005-Y27 [2005 December 23]
    Further to the note about C/2005 W5 at the end of MPEC 2005-X14 and its possible linkage to one of the Marsden-group comets of 1999, Z. Sekanina and P. Chodas, and also R. Kracht, have suggested that a fit to C/1999 U2 seems most likely. The linkage, giving a period of 6.10 years, is from the C2 observations. It should be noted that, although all the observations of C/2005 W5 are from least-squares cubic reductions (i.e., using 11 or more reference stars), in the case of C/1999 U2 this is true only for the observations shown with note 1 (rather than 2) in column 14. For the remainder it was necessary to make only quadratic reductions, and the observations from 1999 10 24.70145 onward are particularly unsatisfactory. Since the orbits below also reasonably represent the generally inferior C3 observations in both 1999 and 2005 (i.e., without systematic residuals above about 70 arcsec), it seems likely that the linkage is in fact correct.

    For further information on the discovery of these objects see this year's SOHO discoveries.


    SOLWIND Kreutz group comets
    1981 W1 (SOLWIND)(IAUC 8566, 2005 July 12)
    1983 N2 (SOLWIND)(IAUC 8573, 2005 July 25)
    1984 Q1 (SOLWIND)(IAUC 8573, 2005 July 25)
    were discovered by Rainer Kracht on archival images taken with the SOLWIND coronograph and have not been observed elsewhere. They were sungrazing comets of the Kreutz group and were not expected to survive perihelion. They were all from sub-group I.
    SOHO Kreutz group comets
    1997 E2 SOHO(IAUC 8483, 2005 February 11)
    1997 J6 SOHO(IAUC )
    1998 U7 SOHO(IAUC )
    2000 S6 SOHO(IAUC )
    2001 Q9 SOHO(IAUC )
    2001 S3 SOHO(IAUC )
    2005 A2 SOHO(IAUC 8483, 2005 February 11)
    2005 A3 SOHO(IAUC 8483, 2005 February 11)
    2005 A4 SOHO(IAUC 8483, 2005 February 11)
    2005 A5 SOHO(IAUC 8483, 2005 February 11)
    2005 B2 SOHO(IAUC 8475, 2005 February 2)
    2005 B3 SOHO(IAUC 8488, 2005 February 27)
    2005 C2 SOHO(IAUC 8498, 2005 March 24)
    2005 C3 SOHO(IAUC 8498, 2005 March 24)
    2005 E3 SOHO(IAUC 8494, 2005 March 16)
    2005 E4 SOHO(IAUC )
    2005 E5 SOHO(IAUC )
    2005 E6 SOHO(IAUC )
    2005 E7 SOHO(IAUC )
    2005 E8 SOHO(IAUC )
    2005 E9 SOHO(IAUC )
    2005 F1 SOHO(IAUC )
    2005 F2 SOHO(IAUC )
    2005 F3 SOHO(IAUC )
    2005 F4 SOHO(IAUC )
    2005 F5 SOHO(IAUC )
    2005 G3 SOHO(IAUC )
    2005 G4 SOHO(IAUC )
    2005 G5 SOHO(IAUC )
    2005 G6 SOHO(IAUC )
    2005 G7 SOHO(IAUC )
    2005 H3 SOHO(IAUC )
    2005 H4 SOHO(IAUC )
    2005 H5 SOHO(IAUC )
    2005 H6 SOHO(IAUC )
    2005 H8 SOHO(IAUC )
    2005 J3 SOHO(IAUC )
    2005 J4 SOHO(IAUC )
    2005 J5 SOHO(IAUC )
    2005 J6 SOHO(IAUC )
    2005 J7 SOHO(IAUC )
    2005 J8 SOHO(IAUC )
    2005 J9 SOHO(IAUC )
    2005 J10 SOHO(IAUC )
    2005 J11 SOHO(IAUC )
    2005 J12 SOHO(IAUC )
    2005 K5 SOHO(IAUC )
    2005 K6 SOHO(IAUC )
    2005 K7 SOHO(IAUC )
    2005 K8 SOHO(IAUC )
    2005 K10 SOHO(IAUC )
    2005 L6 SOHO(IAUC )
    2005 L7 SOHO(IAUC )
    2005 L8 SOHO(IAUC )
    2005 L9 SOHO(IAUC )
    2005 L10 SOHO(IAUC )
    2005 L11 SOHO(IAUC )
    2005 L12 SOHO(IAUC )
    2005 L13 SOHO(IAUC )
    2005 L14 SOHO(IAUC )
    2005 L15 SOHO(IAUC )
    2005 M2 SOHO(IAUC )
    2005 M4 SOHO(IAUC )
    2005 M5 SOHO(IAUC )
    2005 M6 SOHO(IAUC )
    2005 M7 SOHO(IAUC )
    2005 M8 SOHO(IAUC )
    2005 M9 SOHO(IAUC )
    2005 M10 SOHO(IAUC )
    2005 N6 SOHO(IAUC )
    2005 N7 SOHO(IAUC )
    2005 N8 SOHO(IAUC )
    2005 N9 SOHO(IAUC )
    2005 N10 SOHO(IAUC )
    2005 O3 SOHO(IAUC )
    2005 O4 SOHO(IAUC )
    2005 O6 SOHO(IAUC )
    2005 P1 SOHO(IAUC )
    2005 P2 SOHO(IAUC )
    2005 Q7 SOHO(IAUC )
    2005 Q9 SOHO(IAUC )
    2005 Q10 SOHO(IAUC )
    2005 R5 SOHO(IAUC )
    2005 R6 SOHO(IAUC )
    2005 R7 SOHO(IAUC )
    2005 S1 SOHO(IAUC )
    2005 S5 SOHO(IAUC )
    2005 S6 SOHO(IAUC )
    2005 S7 SOHO(IAUC )
    2005 S8 SOHO(IAUC )
    2005 S9 SOHO(IAUC )
    2005 S10 SOHO(IAUC )
    2005 S11 SOHO(IAUC )
    2005 S12 SOHO(IAUC )
    2005 S13 SOHO(IAUC )
    2005 T6 SOHO(IAUC )
    2005 T7 SOHO(IAUC )
    2005 T8 SOHO(IAUC )
    2005 T10 SOHO(IAUC )
    2005 T11 SOHO(IAUC )
    2005 U2 SOHO(IAUC )
    2005 U3 SOHO(IAUC )
    2005 U4 SOHO(IAUC )
    2005 U5 SOHO(IAUC )
    2005 U6 SOHO(IAUC )
    2005 U7 SOHO(IAUC )
    2005 U8 SOHO(IAUC )
    2005 V2 SOHO(IAUC )
    2005 V3 SOHO(IAUC )
    2005 V4 SOHO(IAUC )
    2005 V5 SOHO(IAUC )
    2005 V6 SOHO(IAUC )
    2005 V7 SOHO(IAUC )
    2005 V9 SOHO(IAUC )
    2005 W6 SOHO(IAUC )
    2005 W7 SOHO(IAUC )
    2005 W8 SOHO(IAUC )
    2005 W10 SOHO(IAUC )
    2005 W12 SOHO(IAUC )
    2005 W13 SOHO(IAUC )
    2005 W14 SOHO(IAUC )
    2005 W15 SOHO(IAUC )
    2005 W16 SOHO(IAUC )
    2005 W17 SOHO(IAUC )
    2005 X2 SOHO(IAUC )
    2005 X3 SOHO(IAUC )
    2005 X4 SOHO(IAUC )
    2005 X5 SOHO(IAUC )
    2005 X6 SOHO(IAUC )
    2005 X7 SOHO(IAUC )
    2005 X9 SOHO(IAUC )
    2005 Y3 SOHO(IAUC )
    2005 Y4 SOHO(IAUC )
    2005 Y5 SOHO(IAUC )
    2005 Y6 SOHO(IAUC )
    2005 Y7 SOHO(IAUC )
    2005 Y9 SOHO(IAUC )
    2005 Y10 SOHO(IAUC )
    were discovered with the SOHO LASCO coronographs and have not been observed elsewhere. They were sungrazing comets of the Kreutz group and were not expected to survive perihelion. Some of these comets show no tail at all and it is possible that some supposed observations of Vulcan were actually tiny Kreutz group comets. Details of the SOHO Kreutz comets discovered or announced this year are listed here, with an abbreviated list here.
    1984 R1 (SOLWIND)
    This is a non-group comet that was discovered by Rainer Kracht in archival SOLWIND images in August 2005. Orbital elements are on IAUC 8583 [2005 August 13].
    1995 O1 (Hale-Bopp)
    A. Rivkin and R. Binzel, Massachusetts Institute of Technology, report that images of C/1995 O1 obtained on Jan. 8 with the Magellan Observatory's Clay 6.5-m telescope (+ SDSS g', r', and i' filters) show a tail at least 8".5 long (through g' and r' filters) and the following coma magnitudes in a 4".2 aperture: g' = 20.73, r' = 20.33, i' = 20.06. [IAUC 8479, 2005 February 7]
    1997 B4 (SOHO)
    1997 V7 (SOHO)
    These are non-group comets discovered by Rainer Kracht in archival C3 images in March 2005. Orbital elements are on MPEC 2005-F31 [2005 March 21] and Brian Marsden notes that the orbits, although uncertain, appear to be retrograde. [IAUC 8500, 2005 March 29]
    2000 QJ46 (P/LINEAR)
    A 19th magnitude asteroid found by LINEAR on 2000 August 24.27 was found to show a coma and tail on archival Sloan Digital Sky Survey images taken just over a week later. The comet has a 14.4 year period, with perihelion at 1.93 AU in 2000 December.
    2000 V4 (SOHO)
    C/2000 V4 appears to be related to C/2001 T5 (MPEC 2001-V10). This was pointed out by R. Kracht prior to the derivation of the above positions and the orbit computation. [MPEC 2005-G93, 2005 April 15]
    2002 EX12 (169P/NEAT) An object discovered by NEAT on 2002 March 15.27, was found to show a tail in late July 2005 by two independent groups of observers. It had not shown a tail when observed two months earlier. It reaches perihelion at 0.6 AU in mid September and has a period of 4.2 years. The orbit is secure, the object having been linked to observations made by Spacewatch in 1998 and the DSS in 1989, and it has been numbered 169.
    2005 A1 (LINEAR)
    LINEAR discovered a new 15th magnitude comet on January 13.48. It is predicted to reach perihelion at 0.91 AU in mid April, and whilst it may then be around 8th magnitude it will be at high southern declination. It might become visible to UK observers at 13th magnitude in late July.

    R. Kracke reports the LINEAR discovery of a comet (discovery observation below). After posting on the `NEO Confirmation Page', other observers have confirmed the cometary nature on CCD images, including C. Jacques and E. Pimentel (Belo Horizonte, Brazil; 0.30-m reflector, Jan. 14.3 UT; coma diameter about 15" and a noticeable 75"-long tail in p.a. 313 deg) and J. Young (Table Mountain 0.6-m reflector, Jan. 14.5, moderate cirrus clouds; slightly elongated 12" coma of mag 15.0 and a 1'-long broad tail in p.a. 295 deg). [IAUC 8463, 2005 January 14]

    Brian Marsden notes on MPEC 2005-F50 [2005 March 29] that

    The "original" and "future" barycentric values of 1/a are +0.000218 and -0.000370 (+/- 0.000026) AU^-1, respectively.
    The "original" value suggests that this is not a "new" comet.

    An observation by Juan José González Suárez, observing with a 20cm SCT x100 on January 17.25 suggests that it is 11.5, significantly brighter than the LINEAR discovery magnitude. By early February southern observers were estimating it at 10th magnitude, with an estimate of 9th magnitude by mid February. By early March most observers were reporting it at 8th magnitude. There have been suggestions of an outburst, but this isn't entirely clear from the light curve. If one did occur, it was towards the end of March.

    Observations by Spanish amateurs in July show that the comets nucleus has split, with Sekanina calculated separation having occurred around April 23. Jeremy Shears has reported the detection of the secondary condensation in the tail of the comet in images taken in early September. Visual observations suggest a total magnitude around 12.

    42 observations received so far suggest a preliminary light curve of m = 8.5 + 5 log d + 10.2 log r

    Observations in ICQ format, last observation 2005 May 12, updated 2005 June 1.


    A/2005 AB [Catalina]
    Another possibly interesting asteroid, of 18th magnitude, discovered by the Catalina Sky Survey on January 1.43. It has a period of 5.7 years and perihelion at 1.18 AU in late March. [MPEC 2005-A05, 2005 January 3, 1.5-day orbit]. It can approach Jupiter within 0.4 AU. Further observations show it is an Amor type, and is a binary.
    2005 B1 (Christensen)
    Eric Christensen discovered a distant 17th magnitude comet near perihelion during the Catalina Sky Survey on January 16.46. It has been linked to asteroid 2004 FS101 and this has allowed an improved orbit to be calculated. The comet reaches perihelion at 3.20 AU in late February 2006, when it may be 14th magnitude. It will be at high northern declination, but at lower culmination, so that there will be evening and morning observing windows.

    E. J. Christensen reports his discovery of a comet (discovery observation below; 10" tail in p.a. 250 deg) on images taken with the 0.68-m Schmidt telescope in the course of the Catalina Sky Survey. Following posting on the 'NEO Confirmation Page', J. Young reported that his CCD images taken through moderate cirrus clouds with the Table Mountain 0.6-m reflector on Jan. 16.5 UT show a 5" coma and a broad tail 25" long spanning p.a. 240-260 deg. M. Tichy found the object to be diffuse with a tail in p.a. 255 deg on images taken by himself and J. Ticha with the Klet 1.06-m telescope. [IAUC 8466, 2005 January 17]

    An object reported as asteroidal by LINEAR (2004 Mar. 23) and by Spacewatch (2004 Mar. 18 and 26), and published as 2004 FS_101 (MPS 104028, 110712; initial orbit on MPEC 2004-O45 and MPO 66351) has been identified with C/2005 B1. [IAUC 8469, 2005 January 19]

    Brian Marsden notes on MPEC 2005-K26 [2005 May 23] that

    The "original" and "future" barycentric values of 1/a are -0.000013 and +0.000214 (+/- 0.000003) AU^-1, respectively
    The "original" value suggests that this is a "new" comet.
    A/2005 BY1 [Steward]
    This asteroid, of 20th magnitude, was discovered at the Steward Observatory on January 18.16. It has a period of 5.5 years and perihelion at 0.97 AU in mid June. [MPEC 2005-B27, 2005 January 19, 1-month orbit]. There have been no recent approaches to Jupiter.
    2005 C4 (SOHO)
    This was a non-group comet discovered by Rainer Kracht in C2 images on February 13. Orbital elements on MPEC 2005-F32 [2005 March 21] give perihelion at 0.0391 AU on February 13.3. [IAUC 8498, 2005 March 24]
    2005 D1 (SOHO)
    This was a non-group comet discovered by Hua Su and Xing Gao in C2 images on February 23. Orbital elements on MPEC 2005-E01 give perihelion at 0.0468 AU on February 23.6, with an inclination of 122 degrees, however Brian Marsden notes that an inclination near 90 degrees and a smaller perihelion is equally possible.
    2005 E1 (P/Tubbiolo)
    A F Tubbiolo has discovered a 21st mag comet on Spacewatch images taken on March 3.26. Further astrometric observations allowed an improved orbit to be calculated by Hirohisa Sato, and this suggests that the comet is in a distant periodic orbit, and is near perihelion. These calculations were confirmed by Brian Marsden on MPEC 2005-F27 [2005 March 22]. The period is 19.4 years, with perihelion having taken place at 4.44 AU in mid March.
    2005 E2 (McNaught)
    Rob McNaught discovered a 16th magnitude comet on March 12.75 with the 0.5m Uppsala Schmidt, during the course of the Siding Spring Survey. It is expected to reach perihelion at 1.52 AU in late February 2006, when it could reach 9th magnitude. It should become visible to UK observers in December and will remain visible at 9 - 10 magnitude until April, when it enters solar conjunction.

    Brian Marsden notes on MPEC 2005-K27 [2005 May 23] that

    The "original" and "future" barycentric values of 1/a are +0.000152 and -0.002367 (+/- 0.000031) AU^-1, respectively.
    The "original" value suggests that this is not a "new" comet.

    Observations by Juan José González Suárez" with a 20cm SCT show that the comet was around 11.5 in early September, though other observers have made it up to a couple of magnitudes fainter. Clear, transparent skies are essential to see the comet as it is still at a very low altitude for European observers.

    59 observations received so far suggest a preliminary light curve of m = 6.8 + 5 log d + 8.5 log r


    A/2005 EO70 [LINEAR]
    This asteroid, of 19th magnitude, was discovered by LINEAR on March 8.42. It has a period of 6.1 years and perihelion at 1.09 AU in mid April. [MPEC 2005-E52, 2005 March 10, 2-day orbit]. It can approach to 0.4 AU from Jupiter and 0.15 AU from Earth. Such an orbit is similar to those of Jupiter family comets.
    A/2005 EW169 [Mt Lemon]
    This asteroid, of 20th magnitude, was discovered by E J Christensen during the Mt Lemon Survey with the 1.5-m reflector on March 11.37. It has a period of 5.1 years and perihelion was at 1.03 AU in mid November 2004. [MPEC 2005-E80, 2005 March 14, 2-day orbit]. It can approach to 0.5 AU from Jupiter and is a potentially hazardous asteroid approaching to 0.016 AU from Earth at the ascending node. Such an orbit is similar to those of Jupiter family comets.
    2005 EL173 (LONEOS)
    This asteroid, discovered by LONEOS on March 8 is in a retrograde orbit.[MPEC 2005-F48, 2005 March 29] The MPC are classifying it as a cubewano or scattered disc object. Perihelion is at 3.9 AU in 2007 March according to the latest orbit [MPEC 2005-G25]. It has a period of 57,000 years. Aphelion is at 3000 AU. There have been no recent close approaches to Jupiter or Saturn. The orbit is typical of a long period comet and the object may show activity as it nears perihelion.

    Somewhat as expected from the orbit this object has finally shown cometary characteristics. Alan Fitzsimmons using the 3.6-m NTT at ESO found that the object had a coma on 2005 May 10.0. Further observations, reported on MPEC 2006-A63 [2006 January 12] show a hyperbolic orbit with perihelion at 3.89 AU in early March 2007.

    Brian Marsden notes on MPEC 2006-C63 [2006 February 11] that

    The "original" and "future" barycentric values of 1/a are +0.000060 and -0.000021 (+/- 0.000005) AU^-1, respectively.
    The "original" value suggests that this is a "new" comet from the Oort cloud.
    2005 G1 (LINEAR)
    LINEAR discovered another comet, of 19th magnitude, on April 1.39. It is predicted to reach perihelion at 5.0 AU in late February 2006.

    Brian Marsden notes on MPEC 2005-M21 [2005 June 20] that

    The "original" and "future" barycentric values of 1/a are -0.000028 and +0.000003 (+/- 0.000043) AU^-1, respectively.
    The "original" value suggests that this is a "new" comet from the Oort cloud.
    2005 GF8 (LONEOS)
    An 18th magnitude asteroid discovered by LONEOS on April 2.43 has been found to show a coma by amongst others, Peter Birtwhistle. The object has perihelion at 2.8 AU in mid August and has a period of 14.2 years.
    A/2005 GF81 [Mt Lemon]
    This asteroid, of 20th magnitude, was discovered by A Grauer during the Mt Lemon Survey with the 1.5-m reflector on April 9.19. It has a period of 5.5 years and perihelion is at 1.08 AU in mid June 2005. [MPEC 2005-G72, 2005 April 11, 2-day orbit]. It can approach to 0.4 AU from Jupiter and 0.1 AU from Earth. Such an orbit is similar to those of Jupiter family comets, although it is classed as an Amor asteroid.
    2005 H1 (LINEAR)
    LINEAR discovered another comet, of 19th magnitude, on April 30.32. It was at perihelion at 4.8 AU in late October 2004, and has a period of over 200 years.

    Brian Marsden notes on MPEC 2005-O04 [2005 July 18] that

    The "original" and "future" barycentric values of 1/a are +0.022106 and +0.022575 AU^-1, respectively.
    The "original" value shows that this is not a "new" comet from the Oort cloud.
    2005 H7 (SOHO)
    This was a non-group comet discovered by Rainer Kracht in C2 images on April 26. Orbital elements on MPEC 2005-k44 [2005 May 26] give perihelion at 0.0127 AU on April 25.60, however Brian Marsden notes that the orbit is indeterminate.
    A/2005 HL3 [Siding Spring]
    This ususual asteroid, of 17th magnitude, was discovered during the Siding Spring Survey with the 0.5m Uppsala Schmidt on April 19.47. It has a period of 31 years and perihelion is at 1.88 AU in early May 2005. [MPEC 2005-H19, 2005 April 21, 2-day orbit]. Aphelion is at 18 AU. It has made no recent close approaches to Jupiter or Saturn.
    A/2005 HC4 [LONEOS]
    This 19th magnitude asteroid, discovered by LONEOS on April 30.31 has perihelion at 0.0574 AU in mid June, and a period of 2.85 years.[MPEC 2005-J02, 2005 May 1, 2-day orbit]. It will pass through the SOHO coronagraph fields in mid June, though the predicted magnitude is fainter than 15.
    2005 J1 (P/McNaught)
    Rob McNaught discovered a periodic comet of 18th magnitude during the Siding Spring Survey on May 3.72. The comet was at perihelion at 1.5 AU in mid April and has a period of 6.7 years. It will fade.
    2005 J2 (Catalina)
    An apparently asteroidal object of 19th magnitude found by the Catalina Sky Survey on May 12.16 and placed on the NEOCP has been found to show cometary features. It was at perihelion at 4.3 AU in March 2005.
    2005 JN (P/Spacewatch)
    An apparently asteroidal object of 20th magnitude found by Spacewatch on May 3.20 has been found to show cometary features. It reaches perihelion at 2.3 AU in June 2005 and has a period of 6.5 years.
    2005 JQ5 (P/Catalina)
    An apparently asteroidal object of 17th magnitude found by the Catalina Sky Survey on May 6.28 has been found to show cometary features. It reaches perihelion at 0.83 AU in late July 2005 and has a period of 4.4 years. It may come within visual range in June.

    The comet will pass 0.056 AU from Earth on 2058 June 17, and will be less than 0.1 AU from Earth between the 8th and 26th.


    2005 JD108 (P/Catalina-NEAT)
    An 18th magnitude comet found by NEAT on June 28.40 has been linked to an asteroid detected by the Catalina Sky Survey on May 12.43 and with observations by LONEOS on May 13. It reached perihelion in mid August 2005 at 4.03 AU and has a period of 16.3 years.
    2005 JY126 (P/Catalina)
    An 18th magnitude comet found during the Catalina Sky Survey on June 7.32 has been linked to an asteroid detected at the Steward Observatory on May 3.37, and with earlier observations by the Catalina Sky Survey on April 17.40. It reached perihelion in late February 2006 at 2.13 AU and has a period of 7.3 years.
    A/2005 JM3 [Catalina]
    This ususual asteroid, of 19th magnitude, was discovered during the Catalina Sky Survey with the 0.68m Schmidt on May 3.31. It has a period of 5.9 years and perihelion is at 1.31 AU in mid June 2005. [MPEC 2005-K13, 2005 May 17, 13-day orbit]. The orbit approaches within 0.1 AU of Jupiter, but there have been no close approaches to the planet over the past few hundred years.
    2005 K1 (Skiff)
    Brian Skiff discovered 17th magnitude comet during the LONEOS sky survey on May 16.34. It reaches perihelion in late November at 3.7 AU.

    Brian Marsden notes on MPEC 2005-O05 [2005 July 18] that

    The "original" and "future" barycentric values of 1/a are -0.000011 and -0.000097 (+/- 0.000044) AU^-1, respectively.
    The small "original" value suggests that this is a "new" comet from the Oort cloud.
    2005 K2 (LINEAR)
    LINEAR has discovered an 18th magnitude comet, which reaches perihelion at 0.54 AU on July 5. It was at high northern declination and there were indications that it was large and diffuse, perhaps putting it within visual range.

    Several observers, including Giovanni Sostero and José González reported visual observations, putting at around 12 - 12.5 in early June. On June 8/9 Nicolas Biver and José González reported that it had brightened further to around 10th magnitude and had become more condensed. Two days later I estimated it at 9th magnitude. On June 13.98 it was 8th magnitude in 20x80B, although summer twilight is making the northern sky quite bright. Observations over June 15 - 19 are scattered, but suggest that the comet faded rapidly.

    Images by David Strange, Michael Jager & Gerald Rhemann and Giovanni Sostero & Ernesto Guido over June 12 - 14 suggest the presence of a secondary condensation, implying that the comet had split. Calculations by Zdenek Sekanina suggest that the split took place around April 22. Whilst this may have facilitated the rapid brightning seen in June, it was clearly not the primary cause.

    An image to 16th magnitude taken by Michael Mattiazzo on August 1st does not show 2005 K2, suggesting it has disintegrated.

    18 observations give a preliminary light curve of 15.4 + 5 log d + 46.9 log r
    This suggested that the comet could reach at 5th magnitude at perihelion, however fading seems to have set in after mid June, with the comet peaking at around 8th magnitude.


    2005 K3 (P/McNaught)
    Rob McNaught has discovered another comet with the 0.5-m Uppsala Schmidt during the Siding Spring Survey. This one was found on May 20.79 and was 17th magnitude at discovery. It is in a short period orbit of 4.3 years with perihelion at 1.44 AU in late August. It is predicted to reach 15th magnitude at brightest.

    An improved orbit by Hirohisa Sato has increased the period to 10.0 years with perihelion at 1.54 AU in August. Further observations have decreased the period to 7.1 years with perihelion at 1.51 AU in mid August.


    2005 L1 (P/McNaught)
    Rob McNaught has discovered another comet with the 0.5-m Uppsala Schmidt during the Siding Spring Survey. This one was found on June 2.66 and was 17th magnitude at discovery. It is in a short period orbit of 7.9 years with perihelion at 3.1 AU in mid December.
    2005 L2 (McNaught)
    Rob McNaught has discovered another comet with the 0.5-m Uppsala Schmidt during the Siding Spring Survey. This one was found on June 2.56 and was 19th magnitude at discovery. It reaches perihelion at 3.2 AU in mid July.

    Brian Marsden notes on MPEC 2006-C64 [2006 February 11] that

    The "original" and "future" barycentric values of 1/a are -0.000390 and +0.000198 (+/- 0.000018) AU^-1, respectively.
    The "original" value suggests that this is not a "new" comet from the Oort cloud.
    2005 L3 (McNaught)
    Rob McNaught has discovered another comet with the 0.5-m Uppsala Schmidt during the Siding Spring Survey. This one was found on June 3.68 and was 18th magnitude at discovery. It reached perihelion at 5.6 AU in January 2008.

    Brian Marsden notes on MPEC 2005-P57 [2005 August 15] that

    The "original" and "future" barycentric values of 1/a are +0.000049 and +0.000279 (+/- 0.000010) AU^-1, respectively.
    The small "original" value suggests that this is a "new" comet from the Oort cloud.

    23 observations give a preliminary light curve of 6.1 + 5 log d + [5] log r


    2005 L4 (P/Christensen)
    Eric Christensen discovered an 18th magnitude comet in the course of the Mt Lemon survey on June 13.35. It is in a periodic orbit of 8.3 years with perihelion at 2.37 AU in late August.
    2005 M1 (170P/Christensen)
    Eric Christensen discovered an 20th magnitude comet in the course of the Mt Lemon survey on June 17.41.

    Further observations show that it is a periodic comet with period of 8.6 years and will reach perihelion at 2.93 AU in late January 2006. It has been identified in observations made by NEAT in 1997, so the orbit is now secure and the comet has received a numeric designation.


    2005 M3 (SOHO)
    This was a non-group comet discovered by Hua Su in C2 images on June 19.
    A/2005 MW1 [Siding Spring]
    This ususual asteroid, of 19th magnitude, was discovered during the Siding Spring Survey with the 0.5m Uppsala Schmidt on June 17.71. It has a period of 4.9 years and perihelion is at 1.26 AU in mid July 2005. [MPEC 2005-M35, 2005 June 21, 4-day orbit]. Maik Meyer comments that there is some resemblance to the elements for comet 1884 O1 (D/Barnard)
    A/2005 MW9 [Mt Lemon]
    This ususual Apollo asteroid, of 20th magnitude, was discovered during the Mt Lemon Survey with the 1.5m reflector on June 18.39. It has a period of 6.8 years and perihelion was at 0.40 AU in April 2005. [MPEC 2005-M66, 2005 June 30, 12-day orbit]. It has made no recent close approaches to Jupiter.
    2005 N1 (Juels-Holvorcem)
    C Juels and Paolo Holvorcem discovered a diffuse, 14th mag, comet on CCD images taken with their 7cm f3 refractor at Fountain Hills Observatory on July 2.45, with prediscovery images on June 30 and July 1. The comet reached perihelion in late August at 1.13 AU. Observations in late July suggest that it had brightened to 11th magnitude, but it was not well placed for observation.

    Brian Marsden notes on MPEC 2005-S06 [2005 September 17] that

    The "original" and "future" barycentric values of 1/a are +0.001289 and +0.001814 (+/- 0.000038) AU^-1, respectively.
    The "original" value suggests that this is not a "new" comet from the Oort cloud.

    4 observations give a preliminary light curve of 8.5 + 5 log d + 22.9 log r


    2005 N2 (168P/Hergenrother)
    David Herald has recovered comet 1998 W2 (P/Hergenrother) on images taken with his 0.36m f4 SC reflector on July 4 & 5. The comet is 0.27 days ahead of the prediction on MPC 45658. The comet may reach 16th magnitude in the autumn. Following recovery it has been numbered 168.
    2005 N3 (Larson)
    Steve Larson discovered a 20th magnitude comet during the course of the Mt Lemon Survey on July 5.38. The comet reaches perihelion in mid December at 1.25 AU, when it may be 13th magnitude, but it will not be well placed for observation.

    Further observations show that it is a short period comet with perihelion at 2.2 AU in mid December. The period is 6.8 years. It is unlikely to become brighter than 18th magnitude.


    2005 N4 (Catalina)
    The Catalina Sky Survey discovered an apparently asteroidal 19th magnitude object on July 6.28, which, following posting on the NEOCP, has been found to show a coma. The comet reached perihelion at 2.3 AU in early July. It is in a long period elliptical orbit.
    2005 N5 (Catalina)
    The Catalina Sky Survey discovered another apparently asteroidal 17th magnitude object on July 12.44, which, following posting on the NEOCP, has been found to show a coma and tail. The comet reached perihelion at 1.63 AU in late August. It may brighten to 16th magnitude.

    The latest orbit by Hirohisa Sato shows that it has a period of around 150 years.


    A/2005 NA56 [Mt Lemon]
    This ususual asteroid, of 21st magnitude, was discovered during the Mt Lemon Survey with the 1.5m reflector on July 5.39. It has a period of 5.4 years and perihelion was at 1.37 AU in late October 2004. [MPEC 2005-N78, 2005 July 15, 10-day orbit]. In the current orbit it can approach to around 0.6 AU of Jupiter. Sebastian Hoenig has suggested that it may be linked to comet 41P/Tuttle-Giacobini-Kresak on the basis of similar orbital elements. This may be possible, but any separation would have taken place over 500 years ago. Comet 41P underwent a series of encounters with Jupiter in the sixteenth century, which reduced the perihelion distance from around 1.5 AU to 1.0 AU.
    A/2005 NP82 [Siding Spring]
    This very ususual asteroid, of 19th magnitude, was discovered during the Siding Spring Survey with the 0.5m Uppsala Schmidt on July 6.66. It has a retrograde orbit with a period of 14.9 years and is at perihelion at 3.08 AU in June 2006. [MPEC 2005-O03, 2005 July 17, 11-day orbit]. It can pass within 0.1 AU of Jupiter, with the most recent close approach being in 1872 in an encounter that reduced the inclination from 140 degrees to 130 degrees. An encounter in 1646 reduced the perihelion distance from 3.3 to 3.0 AU. A more distant encounter took place in 1978.
    2005 O1 (NEAT)
    An asteroidal object of 19th magnitude, discovered by NEAT on July 27.40, has been found to show a coma by Alan Fitzsimmons. It was at perihelion at 3.59 AU in mid May 2005 and is now fading. The latest elements show that it is in a long period eliptical orbit, with a period around 360 years.
    2005 O2 (Christensen)
    Eric Christensen discovered an 18th magnitude comet with the 0.5-m Uppsala Schmidt in the course of the Siding Spring Survey on July 31.75. It reached perihelion at 3.33 AU in early September 2005. Further observations show that it is in an elliptical orbit with a period of about 115 years.
    A/2005 OE [Catalina]
    This ususual asteroid, of 19th magnitude, was discovered during the Catalina Sky Survey with the 0.68m Schmidt on July 16.35. It has a period of 259 years and perihelion was at 2.80 AU in January 2005. [MPEC 2005-O16, 2005 July 19, 3-day orbit]. There have been no recent close approaches to Jupiter.
    2005 P3 (SWAN)
    SWAN images released on August 24 showed an obvious comet candidate, that was noted by many observers, including Michael Mattiazzo. Following visual confirmation by Alan Hale and posting on the NEOCP a preliminary orbit shows that it was at perihelion on August 9 at 0.5 AU. It moved northwards, from below the Plough, and faded.

    Orbit calculations by Hirohisa Sato suggested the possibility of an elliptical orbit, with period around 32 years, however as observations accumulated this possibility has receded. It does however move in a long period elipse, with a period around 270 years. He also provides an animation of SWAN images.

    I was able to observe it on August 28.9 from a site outside Cambridge, with 0.20m SCT and 25x100B, estimating it at 10th magnitude, with a 2' diameter, diffuse coma.

    Some observations reported on the internet suggest that it may be fading rapidly, whilst others indicate that it is fading slowly.


    2005 Q1 (LINEAR)
    LINEAR discovered another comet, of 19th magnitude, on August 27.42. The latest MPEC orbit shows that it was at perihelion at 6.4 AU in late August 2005, and Hirohisa Sato has computed a similar orbit.

    Brian Marsden notes on MPEC 2005-V86 [2005 November 14] that

    The "original" and "future" barycentric values of 1/a are +0.000055 and -0.000047 (+/- 0.000048) AU^-1, respectively.
    The small "original" value suggests that this is a "new" comet from the Oort cloud.
    2005 Q3 (SOHO)
    This was a non-group comet discovered by Tony Hoffman in C2 images on August 30. There was initially some speculation that it might belong to the Marsden group, however the orbit does not confirm this.
    2005 Q4 (P/LINEAR)
    A 19th magnitude, asteroidal object discovered by LINEAR on August 31.40 and posted on the NEOCP was shown to have a tail by J Lacruz (Madrid) and J Young (Table Mountain, USA). The comet reaches perihelion at 1.75 AU at the end of September. It is in an eliptical orbit with a period of 9.4 years.
    2005 Q6 (SOHO)
    This was a non-group comet discovered by Hua Su, Tony Hoffman and Maik Meyer in C2 images on August 19.
    2005 R1 (P/NEAT)
    NEAT discovered a cometary object of 18th magnitude on images taken on September 2.43. The comet reached perihelion at 2.05 AU in early October. It is in an eliptical orbit with a period of 13 years. It brightened a little, reaching 17th magnitude in October.
    2005 R2 (P/Van Ness)
    M E Van Ness noted a 17th magnitude cometary object on LONEOS images taken on September 10.41. It is in a short period orbit of 6.3 years and was at perihelion at 2.13 AU in 2005 February. It brightened to visual range in October, but then faded, so this was clearly a temporary outburst. It is unlikely to become brighter than 19th magnitude at the next return.
    2005 R3 (171P/Spahr)
    Comet 1998 W1 (P/Spahr) has been recovered by F. Fratev and E. Mihaylova of Zvezdno Obshtestvo Obsevatory, Plana, with a 0.25-m f/4.7 reflector and by E. J. Christensen with the Catalina 0.68-m Schmidt telescope. The prediction in the 2005 Handbook requires a correction of delta T = -0.2 day. Following recovery the comet was numbered 171.
    2005 R4 (LINEAR)
    A 19th mag asteroid discovered by LINEAR on September 13.41 was shown to have a coma and tail. It will reach perihelion at 5.2 AU in 2006 March.

    Brian Marsden notes on MPEC 2005-V89 [2005 November 14] that

    The "original" and "future" barycentric values of 1/a are +0.001381 and +0.001431 (+/- 0.000246) AU^-1, respectively.
    The size of the "original" value suggests that this comet has made a previous visit to the inner solar system.
    2005 RV25 (LONEOS-Christensen)
    Eric Christensen discovered an 18th magnitude comet with the 0.5-m Uppsala Schmidt in the course of the Siding Spring Survey on October 22.25, which has been confirmed by Peter Birtwhistle and Richard Miles and Rob McNaught. It has been linked to an asteroid discovered by LONEOS on September 11. It reaches perihelion at 3.60 AU in November next year and has a period of 9.0 years.
    2005 S2 (P/Skiff)
    Brian Skiff discovered 19th magnitude comet during the LONEOS sky survey on September 29.28. The initial orbit was currently very indeterminate, and suggested that the comet might reach perihelion in 2010 February at 3.3 AU. Other solutions suggested a very small perihelion distance. However as observations accumulated the orbit changed, and they now show that the comet is periodic, with a 22 year orbit and perihelion at 6.4 AU in 2006 June.
    2005 S3 (P/Read)
    Michael Read has discovered a 19th mag comet on Spacewatch images taken on September 30.41. Further observations suggest a period of 11 years, with the comet at perihelion in 2006 January at 2.8 AU.
    2005 S4 (McNaught)
    Rob McNaught has discovered another comet with the 0.5-m Uppsala Schmidt during the Siding Spring Survey. This one was found on September 30.56, although pre-discovery images were subsequently found back to July 27, and was 19th magnitude at discovery. It reaches perihelion at 5.9 AU in July 2007.

    Brian Marsden notes on MPEC 2006-K48 [2006 May 26] that

    The "original" and "future" barycentric values of 1/a are +0.000409 and +0.000360 (+/- 0.000005) AU^-1, respectively.
    The size of the "original" value suggests that this comet has made a previous visit to the inner solar system.
    2005 SB216 (P/LONEOS)
    A 19th magnitude asteroid discovered by LONEOS on September 30.38 has been found to show a cometary appearance. It is in a 19 year periodic orbit, and does not reach perihelion at 3.8 AU until February 2007. It will slowly brighten.
    2005 SD (P/LINEAR)
    A 17th mag asteroid discovered by LINEAR on September 16.30 was found to have a coma and tail by Spanish amateur astronomers. It will reach perihelion at 1.58 AU in mid November and has a period of 5.5 years. Further observations by other observers however show no cometary features at all, so the cometary designation is likely to be withdrawn.
    A/2005 SB223 [Siding Spring]
    This ususual asteroid, of 19th magnitude, was discovered during the Siding Spring Survey with the 0.5m Uppsala Schmidt on September 30.74. It has a period of around 150 years in a retrograde (just) orbit and perihelion was at 2.77 AU is in November 2005. Aphelion is at 54 AU. [MPEC 2005-T41, 2005 October 6, 6-day orbit].
    2005 T1 (173P/Mueller)
    Comet 1993 W1 (P/Mueller) has been recovered by E. J. Christensen with the Catalina 0.68-m Schmidt telescope and confirmed by astrometry from LONEOS and independently by F. Fratev of Zvezdno Obshtestvo Obsevatory, Plana, with a 0.25-m f/4.7 reflector. The prediction on MPC 54168 requires a correction of delta T = -0.8 day.
    2005 T2 (P/Christensen)
    Eric Christensen discovered a 20th magnitude comet in the course of the Mt Lemon survey on October 7.21. It is in a periodic orbit of 7.5 years and perihelion was at 2.21 AU in mid April.
    2005 T3 (P/Read)
    Michael Read has discovered a 20th mag comet on Spacewatch images taken on October 7.33. It is near perihelion, which is at 6.2 AU next January, and has a period of around 21 years.
    2005 T4 (P/SWAN)
    Rob Matson and Michael Mattiazzo reported a possible comet in SWAN images between October 6 and 13, which was confirmed by ground based observations by Rob McNaught and Eric Christensen. At around 10th magnitude it was at perihelion at 0.6 AU in early October and will fade quickly. An improved orbit by Hirohisa Sato allowed Terry Lovejoy to find pre-discovery images taken on October 9 and October 18. There are some indications in the astrometry that it may be a periodic comet, with period around 25 years according to Hirohisa Sato. These suggestions were confirmed on MPEC 2005-V22 [2005 November 3], and the latest orbit gives a 29 year retrograde orbit, with perihelion at 0.65 AU on October 10.
    2005 T5 (P/Broughton)
    Amateur astronomer John Broughton, of Reedy Creek, Queensland, Australia, has discovered an 18th magnitude comet in images taken with his 51cm f2.7 reflector on October 9.57. Prediscovery observations back to August 26 have been found. It is a periodic comet, with perihelion at 3.25 AU in early November, and a period of 20 years. It will fade.
    A/2005 TC [Mt Lemon]
    This Amor asteroid, of 20th magnitude, was discovered during the Mt Lemon Survey with the 1.5m reflector on October 1.24. It has a period of 7.0 years and perihelion was at 1.04 AU in late August 2005. [MPEC 2005-T17, 2005 October 3, 2-day orbit]. In the current orbit it can approach to around 0.4 AU of Jupiter and was within 0.1 AU of Earth on September 20. This type of orbit is typical of Jupiter family comets. The object is estimated at around 100m in diameter.
    A/2005 TF50 [Steward]
    This unusual asteroid, of 21st magnitude, was discovered at the Steward Observatory on Kitt Peak with the 0.9m reflector on October 10.24. It has a period of 3.3 years and reaches perihelion at 0.27 AU in 2006 January. [MPEC 2005-T90, 2005 October 12, 2-day orbit]. Katsuhito Ohtsuka has pointed out that it may be a member of Taurid complex. Seiichi Yoshida gives more details in his call for observations. It is classed as an Apollo asteroid, and can pass within 0.25 AU of Jupiter, most recently in 1962.
    A/2005 TJ50 [Steward]
    This unusual asteroid, of 21st magnitude, was discovered at the Steward Observatory on Kitt Peak with the 0.9m reflector on October 5.41. It has a retrograde orbit with a period of around 45 years and reaches perihelion at 3.8 AU in mid April next year. [MPEC 2005-T86, 2005 October 12, 9-day orbit].
    2005 U1 (P/Read)
    Michael Read has discovered a 20th mag comet on Spacewatch images taken on October 24.33. It has a period of 5.6 years, with the comet at perihelion in late July at 2.4 AU.
    A/2005 UJ159 [NEAT]
    This unusual asteroid, of 19th magnitude, was discovered by NEAT at at Palomar with the 1.2-m Schmidt on October 30.52. [MPEC 2005-V55, 2005 November 7, 8-day orbit]. It has a a period of 6.1 years and reaches perihelion at 0.6 AU in early January 2006. It is an Apollo asteroid, and is a PHA. It is estimated at 2km in diameter.
    A/2005 UN398 []
    This unusual asteroid has a a period of around 10 years with perihelion at 2.2 AU. [MPEC 2006-F18, 2006 March 3]. The orbit is typical of a Jupiter family comet and it can approach within 0.1 AU of the giant planet. It is estimated at around 11km in diameter.
    2005 V1 (P/Bernardi)
    Fabrizio Bernardi has discovered a 20th magnitude comet on CFH telescope images taken on November 1.62. It has a period of 9.5 years, with perihelion at 2.3 AU in mid August 2005.
    2005 V8 (SOHO)
    This was a non-group comet discovered by Hua Su in C2 images on November 9.

    Brian Marsden notes on MPEC 2005-Y07 [2005 December 19]

    Alternate orbit solutions are of course possible for the non-group comets C/2005 V8 and C/2005 Y1. The orbit of C/2005 V8 is possibly similar to that of C/2005 H7.

    A/2005 VD [Mt Lemon]
    This distant asteroid, of 21st magnitude, was discovered during the Mt Lemon Survey with the 1.5-m reflector on November 1.21. It is in a retrograde orbit and has a period of around 60 years. Perihelion was at 5.20 AU in late October 2005. [MPEC 2005-V32, 2005 November 3, 2-day orbit]. Such an orbit is more typical of a Halley type comet. In the current orbit it can approach to around 0.4 AU of Jupiter. The object is estimated at around 10km in diameter.
    A/2005 VH1 [Steward]
    This unusual asteroid, of 20th magnitude, was discovered at the Steward Observatory on Kitt Peak with the 0.9-m reflector on November 3.19. It reaches perihelion at 1.1 AU in mid December. [MPEC 2005-V43, 2005 November 5, 2-day orbit]. In the current orbit it can approach to around 0.5 AU of Jupiter.
    A/2005 VX3 [Mt Lemon]
    This distant asteroid, of 20th magnitude, was discovered during the Mt Lemon Survey with the 1.5-m reflector on November 1.49. It is in a retrograde orbit and has a period of around 30 years. Perihelion is at 4.0 AU in mid November 2005. [MPEC 2005-V58, 2005 November 8, 5-day orbit].
    2005 W2 (Christensen)
    Eric Christensen discovered a 17th magnitude comet in the course of the Catalina Sky Survey on November 22.28. It is predicted to reach perihelion at 3.3 AU in March 2006, and has a period of around 85 years.
    2005 W3 (P/Kowalski)
    Richard Kowalski discovered a 19th magnitude comet in the course of the Catalina Sky Survey on November 25.32. The comet is a periodic one, with a period of 16 years, and it was at perihelion at 3.0 AU in late August 2005. It will fade.
    2005 WY3 [Spacewatch]
    This unusual asteroid, of 21st magnitude, was discovered by Spacewatch with the 1.8-m reflector on November 21.07. Currently 6.4 AU from the Sun, it reaches perihelion at 1.79 AU in December 2007 and has a period of 19 years. [MPEC 2005-W71, 2005 November 26, 25-day orbit]. In the current orbit it can approach to within 0.5 AU of Jupiter and can also approach within 0.9 AU of Saturn. It is around 14km in diameter.
    2005 X1 (Beshore)
    Edward Beshore discovered a 20th magnitude comet in the course of the Catalina Sky Survey on December 7.41. It has passed perihelion, which was at 2.9 AU in early July 2005. It will fade.
    2005 XA54 (P/LONEOS-Hill)
    On January 6.41 BAA Member Rik Hill found an obvious comet on Catalina Sky Survey images. Tim Spahr has identified this with an asteroid discovered by LONEOS on December 4.38 and observed on two nights. The comet has a period of 15 years and reaches perihelion in early March at 1.8 AU. It could brighten to 16th magnitude in February and March, though it is an intrinsically faint object.
    2005 Y1 (SOHO)
    This was a non-group comet discovered by Steve Farmer in C2 images on December 17.

    Brian Marsden notes on MPEC 2005-Y07 [2005 December 19]

    Alternate orbit solutions are of course possible for the non-group comets C/2005 V8 and C/2005 Y1. The orbit for C/2005 Y1 is heavily weighted toward the C2 data, which for the most part are mutually unusually consistent, with the comet roughly of mag 7-8; the comet was much harder to detect in C3, and these reductions were unusually inconsistent. If this orbit is at all meaningful, a second entry into the C2 field should occur, although the phase angle would be very much larger and the magnitude obviously uncertain.

    2005 Y2 (McNaught)
    Rob McNaught has discovered another comet with the 0.5-m Uppsala Schmidt during the Siding Spring Survey. This one was found on December 30.46, and was 19th magnitude at discovery. The latest orbit confirms early suggestions that it is a periodic comet, with perihelion at 3.4 AU in late December 2004 and a period of 16 years.
    2005 YW (LINEAR)
    This unusual asteroid, of 20th magnitude, was discovered by LINEAR with the 1.0-m reflector on December 21st. Currently 4 AU from the Sun, it reaches perihelion at 2 AU in December 2006 and has a period of over 1000 years. At aphelion it is 190 AU from the Sun. [MPEC 2005-Y43, 2005 December 27, 6-day orbit]. It is classed as a scattered disc object or cubewano and has a diameter of around 15 km. It will reach magnitude 17.5 at the end of 2006, but is then heading towards high southern declination.

    In October 2006, L Buzzi and other Italian amateur observers including Ernesto Guido, Giovanni Sostero, Rolando Ligustri and Sergio Foglia reported that the object had a coma and tail, and was around 15th magnitude. The comet may brighten by a further magnitude towards perihelion.

    Brian Marsden notes on MPEC 2006-T62 [2006 October 12] that

    The "original" and "future" barycentric values of 1/a are +0.005508 and +0.006832 (+/- 0.000006) AU^-1, respectively.
    The size of the "original" value suggests that this comet has made a previous visit to the inner solar system.
    2005 YQ127 (P/LINEAR)
    This unusual asteroid, of 18th magnitude, discovered by LINEAR on December 28, has an orbit typical of Jupiter family comets. It was at perihelion at 1.9 AU in early November 2005 and has a period of 8 years. [MPEC 2006-A07, 2006 January 2, 5-day orbit]. It can approach within 0.3 AU of Jupiter. As an asteroid it was estimated to be around 6km in diameter.

    Further observations have shown cometary characteristics. The latest orbit shows that perihelion was at 1.9 AU in early November 2005, with a period of 7.6 years.


    Ephemerides of current comets are available on the CBAT ephemeris page and positions of newly discovered comets are on the NEO confirmation page.
    More information on LINEAR. A list of comets discovered by selected search programs.
    The Northumberland refractor is the telescope that was used in the search for Neptune. It now has a 0.30-m f20 doublet lens which gives a stellar limiting magnitude of around 15 at the zenith on good nights. The Thorrowgood refractor was built in 1864 and has a 0.20-m f14 doublet lens.
    Published by Jonathan Shanklin. Jon Shanklin - jds@ast.cam.ac.uk