[meteorite-list] New Comet Heading Sunward (Comet C/2004 R2 ASAS)

Tue Sep 14 17:42:39 EDT 2004

NEW COMET HEADING SUNWARD
Roger W. Sinnott
Sky & Telescope
September 10, 2004

Grzegorz Pojmanski (Warsaw Astronomical Observatory, Poland) has 
found an 11th-magnitude comet a few degrees south of Sirius in the 
predawn sky. He snared it remotely using a remarkably small 
instrument: a 70-millimeter-aperture lens (focal length 200 mm) 
and CCD camera of the All Sky Automated Survey (ASAS) in Las 
Campanas, Chile.

The discovery announcement on IAU Circular 8402 includes the 
preliminary orbital elements by Brian G. Marsden, director of the 
Minor Planet Center in Cambridge, Massachusetts. These show that 
Comet ASAS (C/2004 R2) will pass fairly close to the Sun -- both in 
the sky and literally -- during the coming weeks. It reaches 
perihelion on October 7th, well inside the orbit of Mercury and 
just 0.11 astronomical unit from the Sun. For a week or two around 
that time, the only way to see it will be via the Internet on 
images taken by the SOHO spacecraft 
(http://sohowww.nascom.nasa.gov/data/realtime-images.html) 
as the comet glides just 1.2 degrees north of the Sun's center.

Until the end of September, the comet should be visible in 
ordinary telescopes mainly from the Southern Hemisphere (see the 
ephemeris below). If it survives perihelion, it will enter the 
evening sky for skywatchers north of the equator. But because 
this is not an intrinsically large comet, it could go "poof" in 
the Sun's heat. Similar objects studied by comet expert John 
Bortle have done just that.

This ASAS success comes just two months after the discovery of 
Nova Scorpii 2004 using the same equipment. For more about the 
highly automated survey, see Dennis di Cicco's article in SKY & 
TELESCOPE for October 2002, page 18.

The ephemeris below, based on Marsden's elements, gives the 
comet's right ascension and declination at 0 hours Universal 
Time on each date, followed by its distances from the Earth 
(Delta) and Sun (r) in astronomical units. Then are listed its 
elongation from the Sun in degrees, predicted visual magnitude, 
the constellation it is in, and optimum viewing latitude. (If 
the numbers in the table don't line up properly, switch to a 
fixed-space font like Courier.)

Roger W. Sinnott
Senior Editor
SKY & TELESCOPE

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                   Comet ASAS (C/2004 R2)

 2004      RA (2000) Dec   Delta    r   Elong   Mag  Const OpLat
(0h UT)    h  m     o  '    (au)   (au)    o                    

Sep 10    7 46.8  -21 42   0.883  0.913   57    10.9   Pup   30S
Sep 11    7 56.6  -21 56   0.874  0.889   56    10.8   Pup   30S
Sep 12    8 06.6  -22 08   0.866  0.865   54    10.7   Pup   31S
Sep 13    8 16.8  -22 17   0.859  0.840   53    10.6   Pup   31S
Sep 14    8 27.3  -22 24   0.853  0.815   51    10.5   Pup   32S
Sep 15    8 38.0  -22 28   0.849  0.790   50    10.4   Pyx   32S
Sep 16    8 48.8  -22 28   0.846  0.765   48    10.3   Pyx   33S
Sep 17    8 59.7  -22 26   0.844  0.739   46    10.1   Pyx   33S
Sep 18    9 10.8  -22 20   0.844  0.712   44    10.0   Hya   34S
Sep 19    9 21.9  -22 11   0.845  0.686   42     9.9   Hya   34S
Sep 20    9 33.0  -21 58   0.847  0.659   41     9.8   Hya   35S
Sep 21    9 44.2  -21 41   0.851  0.631   39     9.7   Hya   35S
Sep 22    9 55.3  -21 21   0.856  0.603   37     9.5   Hya   36S
Sep 23   10 06.4  -20 56   0.862  0.575   35     9.4   Hya   36S
Sep 24   10 17.4  -20 28   0.871  0.546   33     9.2   Hya   37S
Sep 25   10 28.3  -19 56   0.880  0.516   31     9.1   Hya   37S
Sep 26   10 39.1  -19 21   0.892  0.486   29     8.9   Hya   37S
Sep 27   10 49.7  -18 41   0.904  0.455   27     8.7   Hya   37S
Sep 28   11 00.3  -17 58   0.919  0.424   25     8.5   Crt   38S
Sep 29   11 10.7  -17 10   0.935  0.391   23     8.3   Crt   38S
Sep 30   11 21.0  -16 19   0.952  0.358   21     8.0   Crt   38S
Oct  1   11 31.2  -15 22   0.971  0.324   19     7.8   Crt   37S
Oct  2   11 41.5  -14 20   0.992  0.289   17     7.4   Crt   37S
Oct  3   11 51.9  -13 12   1.014  0.254   14     7.1   Crt   -- 
Oct  4   12 02.5  -11 56   1.038  0.218   12     6.6   Crv   -- 
Oct  5   12 13.5  -10 30   1.062  0.182    9.5   6.1   Vir   -- 
Oct  6   12 25.4  -08 51   1.086  0.149    6.7   5.5   Vir   -- 
Oct  7   12 38.4  -06 58   1.104  0.123    3.5   4.9   Vir   -- 
Oct  8   12 52.8  -04 55   1.111  0.114    1.2   4.6   Vir   -- 
Oct  9   13 07.6  -03 01   1.102  0.126    3.9   5.0   Vir   -- 
Oct 10   13 21.6  -01 28   1.083  0.153    7.1   5.6   Vir   -- 
Oct 11   13 34.7  -00 15   1.059  0.187    9.8   6.2   Vir   -- 
Oct 12   13 47.3  +00 43   1.036  0.223   12     6.7   Vir   -- 
Oct 13   13 59.4  +01 31   1.014  0.259   15     7.1   Vir   -- 
Oct 14   14 11.3  +02 12   0.993  0.294   17     7.5   Vir   38N
Oct 15   14 23.0  +02 46   0.975  0.329   19     7.8   Vir   36N
Oct 16   14 34.7  +03 15   0.958  0.363   21     8.1   Vir   35N
Oct 17   14 46.3  +03 41   0.944  0.396   23     8.4   Vir   34N
Oct 18   14 57.9  +04 03   0.932  0.428   25     8.6   Vir   33N
Oct 19   15 09.5  +04 22   0.922  0.459   27     8.8   Vir   32N
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