IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:34

3 November 2010
IAU Circular No.9175


COMET 2010 V1

S. Nakano, Sumoto, Japan, reports the visual discovery of a
comet independently by Kaoru Ikeya (Mori-machi, Shuchi-gun,
Shizuoka-ken; 25-cm reflector at 39x; diffuse with some
condensation; coma diameter 1' on Nov. 2.831 UT and 2' on Nov.
3.812) and by Shigeki Murakami (Toukamachi, Niigata-ken; 46-cm
reflector at 78x; coma diameter 4' with a 2' tail in p.a. 90 deg on
Nov. 3.801; moving eastward at approximately 2'/hr). Nakano also
forwards astrometry obtained by Koichi Itagaki (Teppo-cho, Yamagata,
60-cm f/5.7 reflector + unfiltered CCD camera), who notes that comet
to be diffuse with strong central condensation but no tail on Nov.
3.85.

2010 UT R.A. (2000) Decl. Mag. Observer
Nov. 2.831 12 32.7 - 1 38 8.5 Ikeya
3.801 12 35.1 - 2 01 9 Murakami
3.812 12 35.0 - 2 01 8.0 Ikeya
3.84701 12 35 04.22 - 2 02 12.5 10.5 Itagaki
3.85035 12 35 04.71 - 2 02 17.2 10.7 "


COMET 103P/HARTLEY

M. Knight and D. Schleicher, Lowell Observatory, report
narrowband imaging of comet 103P using the 0.8-m and Hall 1.1-m
telescopes at Lowell Observatory. Further to Knight et al. (IAUC
9163), the CN gas feature was centered at p.a. about 355 deg on
Aug. 13-17; near 350 deg on Sept. 9-13 and on Oct. 16, 17, and 19;
and at about 5 deg during Oct. 31-Nov. 3. This jet often appears
as a side-on corkscrew in recent images, but it is sometimes less
curved, possibly due to either the effects of a small complex
component to the fundamental rotation and/or an additional fainter
and overlapping jet located closer to the pole. Numerical modeling
of these position angles and the sense of rotation yields a
rotation axis having an obliquity of about 15 deg in the comet's
orbital frame, corresponding to R.A. = 310 deg, Decl. = +80 deg,
assuming principal axis rotation. Preliminary modeling suggests
that the CN jet originates at a latitude of +50 deg to +60 deg. An
additional, fainter CN feature was seen towards the southeast (mid-
Oct.) and east (Oct. 31-Nov. 3). For this pole solution, the
comet's maximum sub-earth latitude is attained in early October,
resulting in an overlap of the two CN features towards the east, as
was observed in the Oct. 12-14 images and possibly explaining the
morphology described by Samarasinha et al. (CBET 2512). With this
pole solution, the sub-earth latitude should be near the comet's
equator at the time of the EPOXI spacecraft encounter, yielding the
side-on corkscrews.

2010 November 3 (9175) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:34

4 November 2010
IAU Circular No.9176


COMET C/2010 V1 (IKEYA-MURAKAMI)

Further to IAUC 9175, additional astrometry have been reported
and appear on MPEC 2010-V46 with the following preliminary
parabolic orbital elements by B. G. Marsden:

T = 2010 Oct. 18.817 TT Peri. = 155.076
Node = 5.844 2000.0
q = 1.71541 AU Incl. = 8.913

Visual total-magnitude and coma-diameter estimates: Nov. 4.23 UT,
7.6, 5' (J. J. Gonzalez, Leon, Spain, 10x50 binoculars); Nov. 4.50,
9.0, 3' (A. Hale, Cloudcroft, NM, 10x50 binoculars; low altitude,
zodiacal light); Nov. 4.52, 7.4, 4' (C. W. Hergenrother, Tucson,
AZ, U.S.A., 30x125 binoculars).
L. Buzzi (Varese, Italy, 0.60-m reflector) reports a round 4'
coma with a tail at least 6' long in p.a. about 300 deg on his CCD
images from Nov. 4.2. W. H. Ryan (Magdalena Ridge Observatory,
2.4-m reflector) reports a prominent tail in p.a. about 315 deg on
R-band CCD images taken on Nov. 4.5.
Corrigendum. On IAUC 9175, line 4, FOR Toukamachi, READ
Tohkamachi,


COMET P/2010 V2 (NEAT)

Comet P/2004 F3 (cf. IAUC 8313) has been recovered on CCD
images obtained at two observatories (initial astrometry tabulated
below). E. Romas (Rostov-na-Donu, Russia), A. Novichonok
(Kondopoga, Russia), and D. Chestnov (Saransk, Russia) write that
forty stacked 120-s images obtained on Nov. 2.0 UT with the 0.5-m
f/8.3 Maksutov-Cassegrain reflector at the Kislovodsk Mountain
Astronomical Station of Pulkovo Observatory show a round, condensed
coma of diameter 10" and a 7" tail in p.a. 300 deg. G. Hug
(Scranton, KS, U.S.A.) found the comet to be slightly diffuse on
images taken with a 0.56-m reflector. The indicated correction to
the prediction on MPC 69908 is Delta(T) = -0.02 day.

2010 UT R.A. (2000) Decl. Mag. Observer
Nov. 2.00192 9 36 52.53 +26 27 56.8 Romas
3.45706 9 37 44.94 +26 29 09.2 20.4 Hug

Additional astrometry, revised orbital elements by B. G. Marsden
(epoch = 2013 Jan. 28.0 TT, T = 2013 Jan. 28.7166 TT, q = 2.879762
AU, e = 0.285069, Peri. = 176.1893 deg, Node = 78.7805 deg, i =
15.9719 deg, equinox 2000.0, P = 8.08 years), residuals, and an
ephemeris appear on MPEC 2010-V47.

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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:34

4 November 2010
IAU Circular No.9177


COMET 103P/HARTLEY

M. F. A'Hearn and L. M. Feaga, on behalf of the DIXI/EPOXI
science team, report that routine sampling with the Deep Impact
Medium Resolution Imager (MRI) enabled the discovery of an unusual
cometary phenomenon on comet 103P (sometimes known by its old name,
"Hartley 2") that may recur. Between Sept. 9 and 17, the
outgassing of CN, as acquired with the CN filter (sensitive to both
the dust continuum and CN gas), increased by a factor of five and
then slowly decreased, returning to its prior trend line by Sept.
24. There was no apparent change in the reflected continuum,
acquired with a clear filter, other than a small, gradual increase
consistent with the increases before and after this period in both
CN and dust due to the decreasing range from the spacecraft to the
comet and the increasing activity of the nucleus as it approaches
the sun. This long-duration, gradual increase and decrease of
gaseous emission without any increase in the dust is very unlike
typical cometary outbursts, which have sudden onsets and are
usually accompanied by considerable dust. It is dissimilar to the
activity observed at comet 9P (old-style name "Tempel 1") and not
apparently associated with the dust-free CN jets observed in this
and other comets. Thus it is not like anything that the authors
are aware of in any other comet. Observers should be aware of this
type of activity when planning observations and interpreting their
data. In addition, H_2O and CO_2 have been unambiguously detected
in the coma using the High Resolution Instrument infrared
spectrometer (HRI-IR) on Oct. 16.

M. Drahus, D. Jewitt, and A. Guilbert, University of
California at Los Angeles; D. Lis, California Institute of
Technology; and W. Waniak, Jagiellonian University, obtained
velocity-resolved spectral time series of HCN at the James Clerk
Maxwell Telescope (JCMT) and the Caltech Submillimeter Observatory
(CSO) on Mauna Kea. JCMT observations of the J=4-3 transition were
carried out from Sept. 29 to Oct. 1 UT and from Oct. 16 to Oct. 19
UT. CSO observations of the J=3-2 line were taken from Oct. 23 to
Oct. 24 UT. A very strong variability of the line area on a time
scale of hours is observed, reaching up to a factor of four, and
accompanied by changes of the line profile. The variability
appears inconsistent with the 16.6-hr rotation period reported by
Meech et al. (2009, BAAS 41, 1029) and Knight et al. (2010, IAUC
9163 and CBET 2418), and with the 17.6-hr period reported by
Samarasinha et al. (CBET 2512). It is anticipated that there will
be a much longer rotation period, significant excitation of the
rotation state (cf. Samarasinha et al., CBET 2512), or a non-
periodic nature of the detected variability.

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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:35

4 November 2010
IAU Circular No.9178


COMET 103P/HARTLEY

N. H. Samarasinha and B. E. A. Mueller, Planetary Science
Institute; and M. F. A'Hearn and T. L. Farnham, University of
Maryland, obtained CN narrowband images at the Kitt Peak National
Observatory 2.1-m telescope from Sept. 30 to Oct. 4 UT. The
enhanced images clearly indicate the rotation of a jet feature
centered around a position angle near 30 deg. This is presumably
the same feature reported by Knight et al. (IAUC 9163). This
feature moves from the northwest towards the earth's direction,
almost towards the line-of-sight, and then moves to the east-
northeast and finally to the far side before starting the cycle
again; while on the far side from the earth, its level of activity
decreases significantly before starting to increase again. The
repeatability of the CN morphology is consistent with a periodicity
around 17.6 hours. Small differences in the morphology during some
cycles suggest that there may be a slight rotational excitation,
probably a low-excitation short-axis mode. The CN coma morphology
is compatible with a nucleus having a high obliquity and a
retrograde rotation and suggests a low-to-mid-latitude active
region in the negative hemisphere. A preliminary estimate for the
rotational angular momentum vector is R.A. = 345 deg, Decl. = -15
deg, and the uncertainty is as large as 20 deg in some directions.
The continuum images from the same observing run show the dust tail,
but no clear jet features are discernible.
CN narrowband images taken at the Kitt Peak 2.1-m telescope
during Sept. 1-3 UT show coma structure nearly similar to, but with
distinct differences from, that described above during Sept. 30-
Oct. 4. In the images from early September, the northwest jet
moves to the south of the nucleus and then towards the east making
an archimedean spiral-like feature. This indicates a low-latitude
active region in the negative hemisphere of the nucleus for the
rotational angular momentum direction described above. There are
subtle indications as to the presence of a second jet, probably
overlapping with the primary jet, in the east/northeast direction.
The best repeatability of the morphology is seen for a periodicity
near 17.1 hours -- in contrast to the near-17.6 hours derived from
the Sept. 30-Oct. 4 data set. The apparent differences in the
periodicities of the repeatability during different observing runs
is suggestive of a changing rotational state and/or a non-principal-
axis rotational state. A preliminary outflow speed based on the
CN features is 0.7 km/s. No obvious feature other than the dust
tail is observed in the continuum images. Due to rapid changes in
the observing geometry during the coming days, the CN morphology is
likely to show distinct evolutions and observers are encouraged to
obtain additional CN images.

2010 November 4 (9178) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:35

4 November 2010
IAU Circular No.9179


COMET 103P/HARTLEY

J. K. Harmon, M. C. Nolan, and E. S. Howell, Arecibo
Observatory; and J. D. Giorgini, Jet Propulsion Laboratory,
obtained 150-m-resolution radar images and radar doppler spectra
of comet 103P/Hartley on Oct. 24-27 using the Arecibo Observatory
12.6-cm planetary radar. The images show the nucleus to be a
highly elongated, bilobate object with a long-axis dimension of at
least 2.2 km. The images give a preliminary rotation period
estimate of 18.1 +/- 0.3 hours, although a less-likely period of
13.2 hours cannot be ruled out. The radar cross section of the
nucleus is 0.04 km^2. The doppler spectra show a broadband echo
component from large (> cm-size) ejected grains in the inner coma.
The radar cross section of the large-grain coma is 0.6 km^2. This
echo component is preferentially redshifted, indicating that the
bulk of the grain ejection is in the anti-earthward direction. The
characteristic radial velocity dispersion of the grains is 4 m/s.

J. Bauer, Jet Propulsion Laboratory (JPL); R. Walker, MIRA;
A. Mainzer and J. Masiero, JPL; R. Beck, F. Masci, and R. Cutri,
IPAC, California Institute of Technology; E. Wright, University of
California, Los Angeles; and the WISE team -- in collaboration with
M. A'Hearn (University of Maryland), K. Meech (University of Hawaii),
C. Lisse (Johns Hopkins University), and Y. Fernandez (University
of Central Florida) -- report initial results based on 12- and 22-
micron infrared photometry of comet 103P taken during May 10-11
(when the comet was at r = 2.3 AU, Delta = 2.0 AU) by the Wide-
field Infrared Survey Explorer (Wright et al. 2010, A.J. 140, in
press). Analyses of the trail signal present in the stacked image
with an effective exposure time of 158.4 seconds yields optical-
depth values near 6 x 10**-10 at a mean anomaly of 0.3 deg trailing
the comet nucleus, in both 12- and 22-micron bands. Analysis of
the dust trail yields beta-parameter values ranging from
approximately 1 x 10**-4 to 2 x 10**-4, consistent with derived
mean trail-grain diameters ranging from approximately 1 to 12 mm.
Photometry of the coma at 22 microns, combined with data from the
University of Hawaii 2.2-m telescope obtained by J. Pittichova, K.
Meech, T. Riesen, and H. Kaluna on May 22 [R-band Af(rho) = 0.84
+/- 0.04 in log cm units], provide constraints on the particle size
distribution expressed as a log-number-density/log-mass slope term
(alpha). Initial results yield values of alpha = -0.88 +/- 0.10 in
[log N(particles/m^2)]/[log mass(kg)] units, steeper than that
found for the inbound particle fluence during the Stardust
encounter of comet 81P (Green et al. 2004, J. Geophys. Res. 109,
E12S04). The extracted nucleus signal at 12 microns is consistent
with a body of average spherical radius of 0.73 +/- 0.10 km,
assuming an emissivity of 0.9.

2010 November 4 (9179) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:35

4 November 2010
IAU Circular No.9180


COMET 103P/HARTLEY

M. J. Mumma, B. P. Bonev, M. A. DiSanti, L. Paganini, G. L.
Villanueva, and Y. L. Radeva, Goddard Space Flight Center (GSFC);
E. L. Gibb, University of Missouri at St. Louis; K. Magee-Sauer,
Rowan University; and J. V. Keane and K. J. Meech, University of
Hawaii (UH), report: "In collaborative runs in mid-October, we
acquired high-resolution infrared spectra with NIRSPEC at the Keck
Observatory. They reveal strong detections of OH* (prompt emission),
many lines of water and HCN, plus detections of the H_2CO Q-branch
(nu_1, 2781 cm**-1), C_2H_6, and CH_3OH. Additional trace species
are under evaluation. The quantitative results given below are
provisional."

J. V. Keane and K. J. Meech, UH; and the above team members
report that on Oct. 19.5 UT the slit was oriented along the
direction of the CN jet (p.a. 350 deg). H_2O was symmetric about
the nucleus, but C_2H_6 was extended in the jet's direction.
Preliminary production rates, rotational temperatures, and
abundance ratios (percent relative to water) are: H_2O (23 lines),
4.8 +/- 0.1 x 10**27 s**-1, 75 +/- 2 K, 100 percent; C_2H_6 (many
Q-branches) 2.96 +/- 0.23 x 10**25 s**-1, 75 K (assumed), 0.61
percent; CH_3OH (Q-branch nu_2-band), 11.2 +/- 0.72 x 10**25 s**-1,
75 K (assumed), 2.3 percent.

B. P. Bonev, Catholic University and GSFC; and the above team
members report that on Oct. 22.5 UT the slit was oriented along the
sun-comet line. Spatial profiles for hydrogen cyanide, methanol,
ethane, and water are fairly symmetric about the nucleus.
Preliminary production rates, rotational temperatures, and
abundance ratios (percent relative to water) are: H_2O (20 lines),
7.2 +/- 0.29 x 10**27 s**-1, 77 +/- 2 K, 100 percent; HCN (12 lines),
1.7 +/- 0.1 x 10**25 s**-1, 80 K (assumed), 0.24 percent; C_2H_6
(many Q-branches), 2.96 +/- 0.23 x 10**25 s**-1, 75 K (assumed),
0.61 percent; CH_3OH (Q-branch nu_2-band), 11.2 +/- 0.72 x 10**25
s**-1, 75 K (assumed), 2.3 percent.

Corrigendum. On IAUC 9175, line 14, FOR and east READ
and south


2010 GW_147, 2010 KW_7, 2010 LG_61, 2010 OM_101, 2010 PO_58

Several more apparently asteroidal objects in retrograde
orbits have been found by the WISE spacecraft in recent months:
2010 GW_147 (MPEC 2010-H33; P approximately 2700 yr, i = 99.7 deg,
q = 5.38 AU); 2010 KW_7 (MPEC 2010-K29; q = 2.56 AU, P
approximately 740 yr); 2010 OM_101 (MPEC 2010-P16; q = 2.13 AU, P
approximately 985 yr); 2010 LG_61 (MPEC 2010-O48, 2010-L63; P
approximately 26.1 yr, q = 3.0 AU, i = 121 deg); and 2010 PO_58
(MPEC 2010-P59; P approximately 19.0 yr, q = 1.37 AU, i = 124 deg).

2010 November 4 (9180) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:36

4 November 2010
IAU Circular No.9181


COMET 103P/HARTLEY

M. L. Sitko, University of Cinnnnati; R. W. Russell and D. L.
Kim, Aerospace Corporation; K. D. Hanna, Brown University; C. M.
Lisse, Johns Hopkins University; M. S. Kelley, University of
Maryland; and D. Griep, E. Volquardson, and P. Sears, NASA Infrared
Telescope Facility (IRTF), report on BASS observations of comet
103P on the NASA 3-m IRTF. Spectroscopy (range 3-13.5 microns) was
obtained on each night during Oct. 20-24 UT, with no more than
about 50-percent variations in brightness. It appeared that the
comet faded at 10 microns on Oct. 22.47 UT, and brightened on Oct.
23.65, but poor seeing makes the amplitude of the variations
uncertain. The temperature of the dust (based on using 7.9- and
13.4-micron points as the continuum) is 290 +/- 7 K, with a
silicate feature approximately 18 +/- 4 percent above the continuum.
The silicate feature is broad and may extend to both shorter and
longer wavelengths than the points used to derive the graybody
continuum. The data in the 5-micron window fall above the
blackbody derived this way. This dust temperature is slightly
higher than the equilibrium value of 270 K for the sun-comet
distance of 1.06 AU, suggesting a significant small-grain
population. The crystalline olivine feature near 11.3 microns is
weak (about 6 percent above the silicate band). Magnitudes that
include some reflected sunlight (uncertainties reflect the seeing-
related uncertainty, not the statistical errors, which were closer
to 0.05 magnitudes): [10-11 microns], 1.75 +/- 0.15; [4.7-5.1
microns], 6.4 +/- 0.3; [3.70 microns; delta(lambda) about 0.27
microns], 9.0 +/- 0.3.


APPARENT FLARE STAR IN TAURUS

Raffaele Castellano, Vico Equense, Italy, reports the
detection of an apparent outburst of a previously unknown variable
star in the field of M45 (the Pleiades cluster) on Oct. 29.898 UT
using a Takahashi BRC250 f/5 refractor (+ FLI Proline 16803 CCD
camera + clear luminance filter). G. Masi (Ceccano, Italy) has
analyzed Castellano's images and reports the following precise
position: R.A. = 3h47m29s.90, Decl. = +23o33'15".7 (equinox
2000.0; uncertainty 0".3 in each coordinate). The USNO-B1.0
catalogue has a red star (1135-0042434) at this position (end
figures 29s.897, 15".47; B-V approximately +1.5). Masi provides
the following red magnitudes for the variable: Oct. 29.9000, [19:;
29.9090, 19.0; 29.9181, 18.5; 29.9271, 16.6; 29.9361, 14.3;
29.9452, 14.6. Masi comments that the object seems to be real,
having a profile and a FWHM similar to the stars around it. An
animation video by Raffaele is posted at the following website URL:
http://www.youtube.com/watch?v=FIc2pqnZ3KQ.

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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:36

5 November 2010
IAU Circular No.9182


COMET C/2010 U3 (BOATTINI)

A. Boattini reports his discovery of a faint comet with a
moderately diffuse coma that is 6"-7" wide and a central
condensation that is about 3"-4" in size on four 30-s co-added CCD
exposures taken with the Mt. Lemmon 1.5-m reflector in Arizona
(discovery observation tabulated below); the coma elongated in p.a.
330 deg (no clear tail). After posting on the 'NEOCP' webpage,
other CCD astrometrists have also noted the object's cometary
appearance, including W. H. Ryan (R-band images, Magdalena Ridge
2.4-m reflector; Nov. 1.2 UT; diffuse with a tail in p.a. about
300 deg; his images from Nov. 3.2, 4.2, and 5.2 show the tail in
p.a. about 330 deg); L. Elenin (Lyubertsy, Russia; unfiltered
exposures taken remotely, 0.45-m f/2.8 astrograph, ISON-NM
Observatory near Mayhill, NM, USA; Nov. 1.4; coma diameter about
10", faint tail about 13" long in p.a. 335 deg); S. Foglia (10"
coma, wide tail toward p.a. 330 deg on frames taken by P. Miller,
P. Roche, A. Tripp, and himself; 2.0-m 'Faulkes Telescope North' at
Haleakala; Nov. 1.6); A. Novichonok (Kondopoga, Russia; images
taken by V. Gerke, Moscow, remotely, 0.40-m telescope at Ka-Dar
Observatory, TAU Station, Nizhniy Arkhyz; Nov. 1.78; round, very
diffuse coma of diameter 0'.3, total mag 18.2); E. Romas (Rostov-na-
Donu, Russia) and Novichonok (0.50-m reflector, Kislovodsk Mountain
Station, Pulkovo Observatory; Nov. 1.9; diffuse coma, diameter 22",
with a strong central condensation of mag about 19.5 and a 25" tail
in p.a. 330 deg); J. E. McGaha (Tucson, AZ, U.S.A., 0.36-m
reflector; Nov. 2.32-2.37; 18" coma elongated in p.a. 315 deg; no
tail); E. Guido, N. Howes, and G. Sostero (frames obtained remotely,
2.0-m 'Faulkes Telescope South'; Nov. 2.55; diffuse coma about 3"
in diameter); S. Foglia and T. Vorobjov (images taken by R. Holmes,
Ashmore, IL, U.S.A., 0.76-m reflector, Nov. 3.2; 10" coma and a 30"
tail in p.a. 330 deg); G. Hug (Scranton, KS, U.S.A., 0.56-m
reflector; Nov. 3.3; diffuse with no detectable tail); and L. Buzzi
(Varese, Italy, 0.60-m reflector, Nov. 4.96; diffuse 9" coma; faint,
broad tail about 12" long centered at p.a. about 355 deg).

2010 UT R.A. (2000) Decl. Mag. Observer
Oct. 31.33341 2 35 22.84 + 9 15 39.4 19.4 Boattini

The available astrometry, the following very preliminary parabolic
orbital elements by B. G. Marsden, and an ephemeris appear on MPEC
2010-V55.

T = 2016 Oct. 17.014 TT Peri. = 52.271
Node = 48.173 2000.0
q = 11.46126 AU Incl. = 31.063

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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:37

6 November 2010
IAU Circular No.9183


COMET 103P/HARTLEY

H. Weaver, Applied Physics Laboratory (APL), Johns Hopkins
University (JHU); P. Feldman, JHU; M. A'Hearn, University of
Maryland; N. Dello Russo, APL/JHU; and A. Stern, Southwest Research
Institute, report the detection of several bands of CO fourth-
positive-group emission from comet 103P during Hubble Space
Telescope (HST) COS ultraviolet spectroscopic observations on Nov.
4.2 and 4.8 UT, which bracket the EPOXI spacecraft's closest
approach time of Nov. 4.583. The CO emissions at the two different
times are identical to within about 15 percent. Preliminary analysis
gives Q(CO) = 2-3 x 10**25 s**-1, assuming that CO is flowing
radially outward from the nucleus with a speed of 0.75 km/s. If
Q(H_2O) is 1.0 x 10**28 s**-1, then CO/H_2O is 0.2-0.3 percent, which
is the smallest CO abundance ever measured in a comet. Several
atomic emissions from S and C were also detected. Analysis of wide-
band visible images also taken via the HST on Nov. 4.568 UT show a
dust jet emanating from the nucleus in the sunward direction at a
celestial position angle of 104 deg.


COMET 238P/READ

H. H. Hsieh, University of Hawaii, reports that observations
of comet 238P/Read on Oct. 5 UT, using the 10-m Keck I telescope on
Mauna Kea, show that the comet has once again become active after
last being observed to be active in December 2005. In a composite
image comprising 1140 s of effective exposure time, the comet
exhibits a short, tapered tail approximately 5" in length pointed
in the anti-solar direction (about 75 deg east of north) and a
small amount of coma (comet FWHM = 0".90, measured perpendicular to
the tail, compared to typical stellar FWHMs of 0".85). The total
R-band magnitude (measured inside a 2".0 aperture) was 22.25 +/-
0.05. This comet is notable for being the second main-belt comet
(MBC; Hsieh and Jewitt 2006, Science 312, 561) to have been
discovered, after 133P/Elst-Pizarro. It is now also the second MBC
after 133P to be confirmed to have recurrent activity, a key
indication that sublimation, perhaps modulated by seasonal effects,
of volatile ice (and not a one-time event such as an impact) is
responsible for the observed activity.


COMET C/2010 V1 (IKEYA-MURAKAMI)

Further to IAUCs 9175 and 9176, S. Nakano relates that K.
Ikeya was visually hunting for comets also on Nov. 1.8 UT, but
nothing was visible at the comet's position then to visual mag 9-10,
despite the fact that his sky conditions were better on Nov. 1.8
than on Nov. 2.8.

2010 November 6 (9183) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:37

8 November 2010
IAU Circular No.9184


OCCULTATION BY (136199) ERIS

Jose L. Ortiz, N. Morales, R. Duffard, A. Thirouin, P. Santos-
Sanz, and I. de la Cueva, Instituto de Astrofisica de Andalucia,
CSIC, Granada, Spain, report that the occultation of a star of
magnitude V about 17 by the dwarf planet (136199) Eris has been
successfully recorded from their remotely-operated 0.4-m ASH2
telescope at S. Pedro de Atacama Celestial Explorations Observatory
in Chile, with the event starting on Nov. 6d02h18m39s +/- 7 seconds
and lasting for 67 +/- 15 seconds. These observations confirm that
the shadow path of the event drifted southward of most of the
latest predictions, which were compiled by B. Sicardy at website
URL http://tinyurl.com/2fsotul, and also by S. Preston at website
URL http://tinyurl.com/2dqqol5.

E. Jehin, J. Manfroid, M. Gillon, D. Hutsemekers, and P.
Magain report that they observed an occultation of a star of
magnitude I about 15.2 by the dwarf planet Eris (then at V about
18.7) on Nov. 6 using the new telescope TRAPPIST at the European
Southern Observatory (La Silla). A series of 3-s exposures of a
field of size 3' x 3' (1".3/pixel) were secured in fast-readout
mode (with a deadtime of 1.5 s), starting at 01h50m UT for one hour.
Seven frames centered at 02h19m34s UT allowed them to derive the
start of the occultation as 02h19m16s.75 +/- 0s.75 and the end as
02h19m47s.6 +/- 0s.2, for a total occultation time of 30.4 +/- 1.0
seconds. The predictions (see above) made by the Rio de Janeiro
group (Assafin et al., Nov. 5) and by J. L. Ortiz estimated the
time of the occultation around 02h18m UT for Chile, in good
agreement with the observations. During the occultation, a point
source is detected with a magnitude corresponding to that of Eris.
A small flux increase was also seen at the middle of the
occultation, which might result from refraction in Eris' atmosphere
(Elliot and Olkin 1996, Ann. Rev. Earth Planet. Sci. 24, 89). Eris
is by far the most-remote solar-system object observed to date via
stellar occultation, with a geocentric distance of about 96 AU.
TRAPPIST is a project driven by the University of Liege, in close
collaboration with the Observatory of Geneva, supported by the
Belgian Fund for Scientific Research and the Swiss National Science
Foundation.


COMET C/2010 V1 (IKEYA-MURAKAMI)

Additional visual total-magnitude estimates (cf. IAUC 9176):
Nov. 5.82 UT, 8.5 (S. Yoshida, Gunma, Japan, 0.40-m reflector);
7.31, 8.5 (J. G. de S. Aguiar, Campinas, Brazil, 25x100 binoculars).

2010 November 8 (9184) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:37

8 November 2010
IAU Circular No.9185


OCCULTATION BY (136199) ERIS

Further to IAUC 9184, Alain Maury also reports on positive
observations of the occultation of a star (V about 17) by minor
planet (136199) Eris on Nov. 6 by Sebastian Saravia, Caisey
Harlingten, and himself from San Pedro de Atacama Celestial
Explorations Observatory. The occultation was recorded with a
50-cm Planewave telescope, using 3-s individual frames; the
occultation lasted a little more than 70 seconds. More information
on the occultation has been posted at the following website URL:
http://www.spaceobs.com/perso/recherche/Eris/. The observed
phenomena are in good agreement with the predictions made by Bruno
Sicardy using observations by M. Assafin, J. L. Ortiz, and W. M.
Owen (see Ortiz et al., IAUC 9184). A preliminary analysis by
Sicardy, combining the occultation duration at La Silla (Jehin et
al., IAUC 9184) and the present observation indicates that Eris has
a diameter < 2320 km -- therefore smaller than Pluto, whose
diameter is > 2340 km.


COMET 103P/HARTLEY

D. C. Lis, California Institute of Technology; D. Bockelee-
Morvan, N. Biver, J. Crovisier, and R. Moreno, LESIA, Observatoire
de Paris; E. Bergin, University of Michigan; P. Hartogh and M. de
Val Borro, Max-Planck-Institute fuer Sonnensystemforschung; M.
Kueppers, European Space Agency; S. Szutowicz, Space Research
Center, Poland; and the team of the Herschel Guaranteed Time Key
Program called "Water and related chemistry of the Solar System",
report that the 1_10-1_01 water line at 557 GHz was mapped in comet
103P with the HIFI instrument aboard the Herschel spacecraft on Oct.
30.6 UT. The peak line area of 20 K km s**-1 (main beam brightness
temperature) corresponds to a water production rate of (1 +/- 0.2)
x 10**28 mol s**-1 (modeling uncertainty).


COMETS C/2001 A5, C/2001 O3, C/2001 R10 (SOHO)

Further to IAUC 9173, additional Kreutz sungrazers have been
found on SOHO website images; K. Battams notes that all were
stellar in appearance, peaking at mag approximately 7.

Comet 1999 UT R.A.(2000)Decl. Inst. F MPEC
C/2001 A5 Jan. 1.363 19 01.0 -24 47 C3 JR 2010-T38
C/2001 O3 July 25.346 8 04.8 +18 11 C3 JR 2010-T38
C/2001 R10 Sept. 2.532 10 29.6 + 7 24 C3 JR 2010-T38

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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:38

18 November 2010
IAU Circular No.9186


BRIAN G. MARSDEN (1937-2010)
It is with deep regret that we must announce the death today
of Brian G. Marsden after a lengthy illness. He will be remembered
as contributing much to celestial mechanics and the dynamics and
orbits of minor bodies of the solar system and as having an
encyclopedic knowledge of the history of astronomy. He was a
dedicated servant to the astronomical community for many decades,
serving as Director of the Central Bureau from 1968 to 2000 (and as
Director Emeritus since then) and as Director of the Minor Planet
Center from 1978 to 2006 (and as Director Emeritus since then). He
also served extensively within Commissions 6 and 20 of the IAU over
the years, being past President of both Commissions. And he was
one of the most visible astronomers in the world over the years in
terms of his generous availability to the news media on behalf of
the astronomical community.


COMET 103P/HARTLEY

Corrigendum. On IAUC 9810, the text of the third sentence of
the third paragraph (Bonev et al. should be changed as follows:
"Preliminary production rates, rotational temperatures, and
abundance ratios (percent relative to water) are: H_2O (20 lines),
(7.04 +/- 0.28) x 10**27 s**-1, 77 +/- 2 K, 100 percent; HCN (12
lines), 1.7 +/- 0.1 x 10**25 s**-1, 80 K (assumed), 0.24 +/- 0.017
percent; C_2H_6 (nu_5 and nu_7 bands), 4.2 +/- 0.32 x 10**25 s**-1,
75 K (assumed), 0.60 +/- 0.051 percent; CH_3OH (nu_2 and nu_9 bands),
14.0 +/- 2.0 x 10**25 s**-1, 75 K (assumed), 1.99 +/- 0.30 percent."
Total-magnitude estimates: Oct. 30.95 UT, 5.7, 15' coma (A.
Diepvens, Balen, Belgium, 20x50 binoc.); Nov. 4.14, 4.8, 45' (J. J.
Gonzalez, Leon, Spain, naked eye); 8.14, 5.7, 30' (T. Karhula,
Virsbo, Sweden, naked eye).


COMETS C/2000 P4, C/2000 P5, C/2000 S8, C/2000 S9 (SOHO)

Further to IAUC 9185, additional Kreutz sungrazers have been
found on SOHO website images; K. Battams notes that C/2000 P5 and
C/2000 S8 were stellar in appearance, the others being slightly
diffuse; they all peaked at mag approximately 7.5 except for C/2000
S9 (mag approximately 7).

Comet 2000 UT R.A.(2000)Decl. Inst. F MPEC
C/2000 P4 Aug. 1.571 8 34.9 +16 38 C3 JR 2010-T37
C/2000 P5 1.571 8 34.5 +16 42 C3 JR 2010-T37
C/2000 S8 Sept.22.571 11 43.8 - 0 34 C3 JR 2010- T37
C/2000 S9 29.888 12 11.2 - 3 24 C3 JR 2010- T37

2010 November 18 (9186) Daniel W. E. Green
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Re: IAU Circulars (IAUCs) - циркуляры МАС - 11/2010

Сообщение Tikhon » 07 дек 2010, 16:39

23 November 2010
IAU Circular No.9187


COMET C/2010 KW_7 (WISE)

R. S. McMillan, University of Arizona, reported that the
presumed asteroidal object 2010 KW_7 discovered by the WISE
spacecraft (discovery observation tabulated below; cf. MPEC
2010-K29; IAUC 9180) appeared slightly more diffuse than nearby
stars in images taken with the Steward Observatory 0.9-m reflector
(+ CCD mosaic) on Oct. 18.5 UT. J. V. Scotti also reported that
nine 120-s co-added R-band images taken on Oct. 18.5 with the 2.3-m
Bok telescope at Kitt Peak reveal a coma diameter of 8" with a very
faint tail extending about 9" in p.a. 215 deg. Scotti's further
co-added images taken on Oct. 28.5 with the Spacewatch 1.8-m
reflector show a coma diameter of 6".3 (total mag 20.1-20.5) and a
broad, faint, fan-shaped tail extending 0'.14 spanning p.a. 222-305
deg. McMillan also reports (via A. Mainzer, Jet Propulsion
Laboratory) that Scotti has measured a coma diameter of 8".5 on
images taken by T. H. Bressi with the 1.8-m Spacewatch II telescope
on Nov. 11 -- and with a coma diameter of 7".4 with a broad, fan-
shaped tail structure extending about 8".8 towards p.a. 180.3
degrees and faintly to a length of about 8".0 in p.a. 275.5 deg
(where the brightest part of the fan was) on R-band images taken by
McMillan, Scotti, and M. L. Terenzoni at the 2.3-m Bok telescope (+
90Prime CCD camera) also on Nov. 11.
J. M. Bauer and J. D. Goguen, Jet Propulsion Laboratory (JPL),
California Institute of Technology, report (also via Mainzer) that
four 300-s R-band images of 2010 KW_7 were taken on Nov. 7.54-7.55
UT with the Palomar 5-m reflector in about 1".5 seeing; the stacked
images reveal a coma and a faint tail extension approximately 7"-8"
in p.a. 287 deg (or roughly anti-solar).
T. Grav and M. Huber, Johns Hopkins University; and J. Bauer,
JPL, report (also via Mainzer) that eight stacked 90-s SDSS-r-band
images of 2010 KW_7, obtained during Nov. 2.44-2.46 UT with the
Apache Point Observatory's 3.5-m telescope (+ SPICAM CCD camera)
show an apparent coma and a faint tail 4"-5" long in p.a. 286 deg.

2010 UT R.A. (2000) Decl. Observer
May 16.06415 9 22 33.13 -21 18 18.8 WISE

The following orbital elements by G. V. Williams are from 57
observations spanning 2010 May 16-Nov. 17.

Epoch = 2010 Oct. 11.0 TT
T = 2010 Oct. 11.3479 TT Peri. = 332.3059
e = 0.974263 Node = 104.7603 2000.0
q = 2.570377 AU Incl. = 147.0620

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