227 observations have been performed between 2004, September and December, (48 positive or possibly positive) about 83 events (16 positive or  possibly positive) by  117  observers, from the 16  following countries (and numbers of observers) :

AT = Austria ( 3 ), BE = Belgium ( 3 ), BY = Belarus ( 1 ), CH = Switzerland  (2),  CZ = Czech Republic ( 2 ),
DE = Germany ( 15 ), ES = Spain ( 24 ), FR = France ( 32 ), IT = Italy ( 4 ), NL = The Netherlands ( 4 ), PL = Poland ( 6 ),
PT = Portugal ( 2  ), RU = Russia ( 5  ), SU = Finland ( 1 ), TR = Turkey ( 2  ),  UK = United Kingdom ( 11 ).

The table hereafter gives the list of the observers abbreviations in alphabetical order, with the number of observations made by each of them.

(cont.)

D. DENISSENKO who observed from 1.5m Russian-Turkish Telescope of Mt Bakyrlytepe Observatory, has been counted as a Turkish observer.

P. LAQUES usually observing from France, E. BREDNER and D. FISCHER, from Germany, observing the Polyxo event from Spain, have been counted as Spanish observers.

TAROT (Acronym for “Télescope à Action Rapide pour les Objets Transitoires”) is an automatic telescope, located at Calern Observatory, dedicated to g-rays bursts optical study; when available, it can be used for various survey programs.

2004 (September to December) Observations

Observations are usually visual and negative, excepted when otherwise specified. All times are in UTC.

2004.09.01 : (939) Isberga / TYC 6345-00095-1u                     FMY      JNK        JVA

FMY, JVA : CCD imaging.

2004.09.03 : (1146) Biarmia / TYC 0506-01568-1                    IMV       RIV

As noticed by  JNK, both observers missed the appulse time.

2004.09.06 : (287) Nephthys / HIP 84012 A = eta Ophiuchi A               MKM

and one positive :

JLX, COF : CCD imaging. Daylight event ! Nephtys is known to have a satellite but no secondary event has been detected.

2004.09.08 : (640) Brambilla / TYC 1308-00634-1u                                LZJ

2004.09.08 : (539) Pamina / TYC 1180-01087-1                       IMV (with OPI)    JNK

IMV : CCD imaging; observers were close to the predicted path.

2004.09.09 : (491) Carina / 2UCAC 30586277          DGG      DLR       HRB       NVI        PWJ        SPL

and two positive :

Positive observations show there has been a shift of the shadow path, about one path width, toward west.

DLR, HRB, PAR : videorecording.

2004.09.16 : (1413) Roucarie / HIP 33965                                 JNK        WGI

2004.09.16 : (638) Moira / TYC 1286-00191-1           BUL       DGE       GFF        HMG      HRU      HSC

                                                                                       JGS        JLX        MLS       QIN        SHB       THO

and one positive :

DNZ, JGS, QIN, THO : videorecording; MLS : CCD imaging.

JLX : blink at ~04:32:48.5 UT, obvious (though only a partial  extinction), probably caused by some brief turbulence peak.

DNZ positive observation reveals a 1.5 and a 0.6 path width shift toward north relative to J. MANEK  (MNK) and to S. PRESTON (PST) predictions, respectively.

2004.09.16 : (784) Pickeringia / TYC 1808-01533-1u               PAH

2004.09.19 : (3141) Buchar / 2UCAC 43932586                       BOL       DGG      FIM        OKE       PAR

OKE: videorecording;  PAR : videorecording, no occultation longer than 0.5 s.

2004.09.22 : (379) Huenna / TYC 1355-00208-1                       JLX (with FVC)   OKE       THO

379 Huenna   is known to have a satellite S/2003_379_1. THO was in the predicted path but probably missed the occultation because of clouds.

JLX : CCD imaging; OKE, THO : videorecording.

2004.09.23 : (535) Montague / TYC 5263-00191-1u                 PAH

2004.09.24 : (2696) Magion / 2UCAC 32940280                      MDV (with JVG)

MDV : videorecording.

2004.09.30 : (141) Lumen / TYC 2434-00810-1u                      HRU      JLX        OKE       PAR

and four positive :

HRU : many blinks; as he was just near the northern limit of the shadow path, he perhaps missed a short occultation.

JLX : late survey; VRA : several interruptions due to clouds.

OKE, PAR : videorecording; TPY : CCD imaging.

Positive observations reveal a slight shift (about one tenth of the path width) toward north, relative to the last prediction. Chords can be fitted with an elongated 165 ´ 110 km  ellipse, 

in agreement with the 135 km mean diameter of (141) Lumen used for calculations.

2004.10.02 : (1736) Floirac / TYC 1334-01392-1       DEN       JLX        JNK        OTA       RTH       VPV

DEN, OTA, RTH : videorecording.

JLX observing location was at 6.76 km N from PST's centreline  (measured on the ground). Tiny blinks (not occultations) probably due to the turbulence  at 00:09:36.2 , 00:10:09.5 (at critical time), 00:10:26.6.

DEN, JLX, RTH and VPV negative observations show there has been a significant shift of the path, as they were close on both sides of, or in the predicted path; the lack of positive observation lets its position remaining unknown.

2004.10.05 : (1546) Izsak / TYC 0160-01877-1u                       PAR

PAR : videorecording; no occultation longer than 0.2 s.

2004.10.05 : (1477) Bonsdorffia  / TYC 2277-00986-1             JGS

JGS : videorecording.

2004.10.05 : (270) Anahita / 2UCAC 24975483                        DGG      LZJ         SHI

SHI : videorecording; no occultation longer than  1 s.

2004.10.08 : (214) Aschera / 2UCAC 29024006                       MDT      SHB

SHB : videorecording, was in the predicted path.

2004.10.08 : (746) Marlu / TYC 2950-01251-1                         BUL       DEN       DKC      FOC       HBR      HDC                                          HRU      JFY LFT        LUE       MDT      RPU       WKL      WSG

BUL has been disturbed by clouds. DKC and WKL were in double station. M. CORBISIERO reported negative observations from SICILIA  (by E. Lo SAVIO from CATANIA (j =37.5 N, l=15.1 E, h =75 m)  and by Ass. AIDA from RAGUSA 
(j =36.9, l=14.7, h=494 m).

DEN, LUE : videorecording.

WSG : late survey; HBR, LFT, HDC, LUE, RPU were in the MNK predicted track. The real path must have been shifted by at least one path width, but the lack of positive observation lets its position remaining unknown.

2004.10.09 : (230) Athamantis / TYC 1863-02328-1                MDT

2004.10.09 : (468) Lina / TYC 6337-00937-1                            FIM        VSP

2004.10.14 : (636) Erika / TYC 1224-00281-1                          JHP

2004.10.15 : (63) Ausonia  / TYC 1921-02606-1                       JHP

and one positive :

OKS : videorecording. Co-observer: Mikael  PAPATHEOCHARIS

This first OKS positive observation shows that the shadow path has been shifted by 0.5 path width, toward south, relative to the prediction. Note that the observed duration is about 30% longer than the maximal predicted value (8.3 s).

2004.10.29 : (297) Caecilia / 2UCAC 43409058                        ELL

ELL : videorecording.

2004.11.02 : (56) Melete / TYC 0651-00524-1                           FOC

2004.11.03 : (648) Pippa / 2UCAC 42531186                           BOL       ESE

BOL :  faint star and hazy sky, several disappearances of  the target star for less than a second, and sometimes for a few seconds, but none corresponding with the appulse time, predicted around 18:22:10.

2004.11.06 : (20755) 2000 BX6 / HIP 24813                                             CAS       FOC

CAS : CCD imaging.

2004.11.06 : (796) Sarita / 2UCAC 45956597

only one positive :

IVY registered a duration close to  the maximum predicted one (4.4 s), so the real path must have been shifted by about one path width (but 45 km only) relative to WINOCCULT¹ prediction.

2004.11.08 : (1247) Memoria / 2UCAC 24982923

only one positive :

BOL was far from the predicted path.

2004.11.08 : (1186) Turnera / 2UCAC 43084182                     BOL

2004.11.10 : (1101) Clematis / TYC 0033-00537-1                   ala           FIM        FOC       trt

ala : videorecording.

2004.11.10 : (306) Unitas / HIP 95577

only one positive :

BCL was in the PST predicted path and the observed duration is in agreement with the one expected from the maximum duration (1.3 s) and the location in the shadow path.

2004.11.10 : (1076) Viola  / HIP 11484                                      FOC       trt           WGI

2004.11.11 : (238) Hypatia / TYC 0158-01520-1                       HMG      RTH

and one positive :

All observers have been disturbed by clouds. JGS, RTH : videorecording.

A second positive observation has been reported  by  V. BUSO and  G. MAZALAN (13.53s) from Argentina, where the occultation took place ~25 minutes after the JGS one. J. MANEK’s 

comment : “Fortunately this second positive is on the other side of profile allowing (not unique) solution with profile 160 ´ 148km. Negative observation of HMG is clearly conflicting with 

the profile. I have tried to fit another possible ellipse and got a solution 193 ´ 137km where Hazel is outside the profile. However this very elongated profile is in conflict with occultation 

results from 2001.03.01 where a solution 149 ´ 144 km is the most probable and also the low amplitude light curve speaks against this very elongated solution. ”

Either HMG missed a  11 s duration occultation (what would be unlikely), either the reported cloud interruption from 04:35:00 to 04:35:40 occurred at least 25 s  later than supposed  

( unlikely too ), either (more probably), profile of (238) Hypatia was irregular and could not be fitted with an ellipse.

The updated central line was off by ~40km  (~1/4 of expected asteroid diameter) and 4 seconds in time.

2004.11.12 : (1683) Castafiore / 2UCAC 30933494                 BOL

2004.11.14 : (3608) Kataev / TYC 1877-00388-1                      BCL       DGG

2004.11.15 : (6420) Riheijyaya / TYC 0251-00137-1                RGE

2004.11.15 : (4449) Sobinov / TYC 1198-00195-1u                  BCL       DGG      PAR

PAR : videorecording. DGG was in the WINOCCULT1 predicted path but uncertainty was large for this small asteroid.

2004.11.16 : (308) Polyxo / HIP 57629         BOL       CAS       FOC       LAB       RCA       RVJ        SPD

and eleven positive :

(cont.)

LZJ and SCB were in double station and registered both the event whereas FOC and another team (Montserrat BELLA, Carles PERELLO), nearly at the same location, missed it.

SCB : CCD imaging, bad conditions; CAS: CCD imaging, very bad conditions (star lost several times).

ala, FCH, MSJ : videorecording.

JLX : All events (D, R2 and R1) seemed almost instantaneous. The double reappearance strongly suggests that HIP 57629 is an  unknown close binary star, with a luminosity ratio near 3.

Chords are rather scattered but can be fitted with a 120 km mean diameter profile, a little under the one used for calculations (148 km). Positive observations and “shepherd” ones by SPD (north) and LAB (south) show the predictions were exact.

2004.11.18 : (106) Dione / TYC 1845-02445-1                          BCL       DKO (with UCK)

BCL was in the predicted path but surely missed the small (~ 0.4) magnitude drop.

DKO : CCD drift-scan.

2004.11.21 : (136) Austria / TAC +04° 07178                           JLX

JLX : CCD imaging.

2004.11.23 : (289) Nenetta / TYC 6303-01365-1                       BOL

Short duration (0.9 s) event, involving a faint star (Mv : 11.7). BOL : many dimmings probably due to turbulence.

2004.11.23 : (41951) 2000 XH10 / 118 TAU A                          BOL

BOL : CCD imaging.

2004.11.25 : (5632) Ingelehmann / TYC 0676-00115-1u          BCL

2004.11.26 : (999) Zachia / TYC 0740-01208-1u                      DGG      FAR       RTH

FAR, RTH : videorecording.

2004.11.26 : (3062) Wren / TYC 0851-00768-1u                      DGG

2004.11.26 : (512) Taurinensis / TYC 0727-00879-1                OKS

OKS : videorecording.

2004.11.27 : (364) Isara / TYC 1316-01896-1                           PAH

2004.11.28 : (238) Hypatia / HIP 30327                                     EBA       ELL

and one positive :

ELL : videorecording; MTN : CCD drift-scan.

EBA, disturbed by clouds, missed the occultation, as MTN was on the same chord but registered an event with duration
 (13.8 s) close to maximal value (16.5 s). This duration shows that the real path was slightly shifted toward north, relative to the prediction.

2004.11.29 : (1712) Angola / TYC 1163-00239-1u                    ELL        JGS        SHB       STV

ELL, JGS, SHB : videorecording

2004.12.04 : (20762) 2000 EE36 / TYC 1930-00827-1 

only one perhaps positive :

OTA comment : “Surrounding stars in field without change. Maybe cloud ?”

2004.12.04 : (1674) Groeneveld  / HIP 15249 (SAO93369)                     JHP

2004.12.05 : (1373) Cincinnati / TYC 3607-00737-1                               FIM        JHP        SPL

2004.12.06 : (489) Comacina  / TAC +03 01572 (GSC 78 515)              BCL       CNS

and three positive or perhaps positive :

PCI, PSY, trt : CCD drift-scan.

BCL was in the MNK predicted path, and PCI just outside it. The real path has been slightly shifted (0.3 path width) toward north. Chords can be fitted with an elongated profile,

156 ´ 129 km, in good agreement with the mean diameter used for calculation (148km).

2004.12.07 : (1280) Baillauda / TYC 1897-00584-1u                               BCL

2004.12.07 : (3955) Bruckner / 2UCAC 44808893                                  BOL

2004.12.07 : (3983) Sakiko / TYC 1885-01187-1                                     BOL

2004.12.07 : (85) Io / 2UCAC 34244090                                                   BOL

and two positive :

PCI : CCD drift-scan, when the motor drive was stopped, the disappearance has already occurred.

GCV : videorecording.

As GCV registered a duration about the same as the maximal predicted value (12.0 s), he was nearly on the central line : the real path has been shifted by about 0.3 path width, toward north.

Results will be discussed with the 2004.12.12 event ones.

2004.12.08 : (976) Benjamina / 2UCAC 31964699                   PAW (with Christina PAPADAKI)                SPL

PAW : CCD imaging, partial survey due to many interruptions.

2004.12.10 : (3587) Descartes / TYC 2426-00817-1                  trt

2004.12.10 : (1998) Titius / TYC 2380-00793-1                        trt

2004.12.10 : (5755) 1992 OP7 / HIP 34677                                BOL

2004.12.11 : (2025) Nortia / 2UCAC 25441851                        trt

2004.12.12 : (2857) Not / HIP 34376                                          PCI         trt

PCI : CCD drift-scan.

2004.12.12 : (85) Io / TYC 0144 01868 1                    BCL       CJM       COF       CZA       DBE       DLR      JFC     JSZ                                                                        KZA       MBU      PGE       PSY        trt

and seventeen positive :

BEI, DLR, FRP : videorecording.

DBE, KZA, DPY, JFC, LJM, LSF, MTN, NNE, PCI, PSY, SPS : CCD drift-scan.

BEI : possible flickering over 1 sec during disappearance.

Positive observations show the real path has been shifted by 0.2 path width toward north, relative to prediction.

EBA did not observe an event related to (85) Io - his observation is more probably spurious, since CZA, a few meters away, didn’t observe any event. Both were situated out of the path,

 ~ 0.25 path width far from the northern border.

On the southern side, “shepherd” observers are CQU, VDC, LJM (positive), JSZ and MBU (negative). PGE was in the shadow path but  missed the occultation.

Chords can be fitted with an elongated profile, 208 ´ 149 km or 210 ´ 150 km (all values ±2 km, reductions by J. SCHWAENEN and E. FRAPPA, respectively). Both are in good agreement with the mean diameter used for calculation (178km).

(85) Io has been involved in previous events, especially two on 2004.12.07 (four chords, of which one is grazing observed from  Japan , star 2UCAC 34244226, and two other chords, star 2UCAC 34244090 , see before). The observations have been reduced by D. HERALD, finding axes of 198 ´ 103 km. So, there is a good agreement on the long axis dimension  (difference about 10 km or 5%).

Note : six chords have been obtained during the 1995.12.10 event, involving HIP 16380, and led to a  194 ´ 138 km profile.

2004.12.13 : (3983) Sakiko / HIP 29188                                     trt           UCK

UCK : CCD drift scan.

2004.12.13 : (1844) Susilva / TYC 1302-01020-1u                    BAO      BOL       PCI

PCI : CCD drift-scan.

2004.12.14 : (4505) Okamura / TYC 1328-01878-1u               PCI         trt

PCI : CCD drift-scan.

2004.12.15 : (774) Armor / TYC 1337-01059-1                        trt

2004.12.16 : (2225) Serkovski / TYC 1239-00467-1                 WGI

2004.12.17 : (2724) Orlov / TYC 1335-00545-1                        trt

2004.12.18 : (2906) Caltech / 2UCAC 39805936                      PCI

PCI : CCD drift-scan.

2004.12.20 : (13012) 1987 SO5  / 2UCAC 42404783                PCI

PCI : CCD drift-scan.

2004.12.20 : (4455) Ruriko / TYC 0760-00049-1                      BOL

2004.12.22 : (1520) Imatra /  TYC 1302-00745-1u                   JSZ         MBU

MBU reported a blink, not confirmed by JSZ 10 meters away.

2004.12.22 : (1354) Botha / 2UCAC 41667812                         trt

2004.12.23 : (1744) Harriet / HIP 26854                                    BOL       PCI

PCI : CCD drift-scan.

2004.12.24 : (8660) Sano / TYC 0298-00511-1                          BOL       trt

2004.12.25 : (1736) Floirac / TYC 0775-00941-1

only one positive :

BUL : Reappearance could not be timed due to short duration of occultation.

This short duration (the maximum predicted value is 4 s) shows that he was just near one of the path borders and that the real path has been slightly shifted (about one path width, but only 30 km) toward south, relative to the  PST prediction.

Two negative observation reports have been received from JOIN (Japanese Occultation Information Network) observers:    Hideto FUKUI and  Miyoshi  IDA.

2004.12.26 : (412) Elisabeta / 2UCAC 26135561                      UCK

UCK : CCD drift-scan.

2004.12.28 : (2065) Spicer / TYC 2436-00063-1                       THO

2004.12.31 : (3955) Bruckner / TYC 2402-00605-1                  SPS

SPS : CCD drift-scan.

We received observation reports, three positive and three negative, from JOIN about the following event :

2004.11.24 : (791) Ani  / TYC 0752-01346-1

We received 12 observation (all negative) reports from New Zealand  about the following event :

2004.12.16 : (791) Ani  / TYC 0750-00713-1

Reports are diffused on Internet by “PLANOCCULT”. To subscribe to this free service, send an E-Mail to listserv@Aula.com with the following text : subscribe planoccult Your Name, Your Country -and to unsubscribe, send an e-Mail to listserv@Aula.com, with text : unsubscribe planoccult.

Received reports and results are summarized on www.euraster.net, a web page maintained by E. FRAPPA from
Saint-Etienne Observatory.

Predictions with finder charts and up-dated shadow path are regrouped (since September 2004) on the EAON web-site: http://astrosurf.com/eaon, maintained by Jean SCHWAENEN.

Please send the reports quickly, about positive as well as negative observations !

Negative observations can sometimes be of as great interest as positive ones : they can be decisive to determine the shape (“shepherd observations”), refine the orbit of the asteroid or discover un unknown satellite ! 

Please DON’T FORGET to use the IAU format for the date :  (YY)YY.MM.DD.

G. REGHEERE gillesregheere@yahoo.fr

13 bis rue de l’église

78890  GARANCIERES  -  France

1 WINOCCULT is a software developed by D. HERALD, dedicated to prediction of asteroidal occultation and reduction of observations.