[Most of this information is paraphrased or copied from FROM THE MINOR PLANET MAILING LIST [date]. For the full text or to subscribe, please visit: MPML Home page: http://www.bitnik.com/mp MPML FAQ: http://www.bitnik.com/mp/MPML-FAQ.html MPML's Yahoogroups page: http://www.yahoogroups.com/group/mpml ] Mr Bill Yeung, a well equipped amatuer astrometrist has found an object in Earth orbit. From his own and other observers measurements over 3 days here are the orbital elements, derived using the orbfit programme associated with the planetarium/charting programe Guide 8. J002E3 is the temporary designation assigned by the observer. As this isnt in orbit around the Sun, this hasnt been replaced by a designation, as is usually the case. Orbital elements relative to the Earth 19002 143 Perigee 2002 Aug 12.242364 TT Epoch 2002 Sep 3.0 TT = JDT 2452520.5 M 158.25875 (2000.0) P Q n 7.27371087 Peri. 197.86606 -0.89385997 0.44471372 a 568562.564 km Node 9.18081 -0.35532406 - 0.62519113 e 0.4547354 Incl. 20.91490 -0.27342119 - 0.64137801 P 49.49d H 26.0 G 0.15 q 310016.997 km From 39 observations 2002 Sep. 3-6; RMS error 1.054 arcseconds To summarize, its motion is currently such that its orbiting the Earth about every 50 days, at distances varying from 310,000Km to 847,000Km On september 6, it was about mag 16( see observation reports) On temporary basis this object has been added to the spacecraft list on the JPL Horizons system. Observations should be reported to the Minor planet Center ( mpc@cfa.harvard.edu ) and to Paul Chodas at JPL( paul.chodas@jpl.nasa.gov ) , whose quick and decisive action is to be applauded ----------------------------------------------------------------------- The unusual object J002E3, formerly on the Minor Planet Center NEO confirmation page, has been loaded into our Horizons system so that interested observers can generate ephemerides. Our latest orbit solution shows that the object is in a loosely bound orbit about the Earth, with a period of about 50 days. This leads us to believe the object is a spacecraft or rocket body, but it has not been associated with any known launch. Further observations of the object are highly desirable to help characterize the nature of the object: we will update our orbit solution as they become available. Telnet and email users of Horizons can access this object by typing "J002E3". Web users of Horizons can access the object by going to the Major Body Menu, selecting the Spacecraft list, and choosing the entry "J002E3 Spacecraft (UNCONFIRMED)". The available time span is currently August 1 through December 1, 2002. The telnet address of Horizons is telnet://ssd.jpl.nasa.gov:6775, and the web address is <http://ssd.jpl.nasa.gov/cgi-bin/eph>. ===================================================================== A further comment about the recent behaviour of this object. The discoverer was amazed that it hadnt been observed sooner. Dr. Chodas's comments give a plausible explanation . ------------------------------------------------------------------------ I agree that the chance of J002E3 being a captured NEA is small, but its orbit is _consistent_ with a captured NEO. Running our nominal orbit solution backwards, I calculate that the object passed through the opposition point only once, around June 17, at just over one half a lunar distance and a skyplane rate of about 100 arc-sec per minute. (Would the surveys have found it at that rate?) Our best orbit solution indicates that the object was likely captured from heliocentric orbit during the April/May time period, as it passed through the L1 Lagrange point between the Earth and the Sun. (These calculations all assume just the nominal set of asteroidal perturbations; perturbations which might be important for a man-made object are neglected.) Another point: even if the object was captured from heliocentric orbit, that doesn't mean it is asteroidal: it could for example be a rocket stage escaped from an earlier cis-lunar orbit. We may never know what this object is, but a longer astrometric data arc may help narrow down the possibilities. Perhaps our best hope, if we get an accurate enough orbit, is to observe the object with radar. ================================================================== Here are the observation, as reported to the Minor Planet Center, in their standard format, to which I have added column headings. TEL 0.45-m Schmidt-Cassegrain + CCD NET GSC-ACT Object ID Year MM dd.ddddd RA Dec Magn. Obs code J002E3 * C2002 09 03.32505 01 13 42.12 +03 12 16.3 16.7 V G78 J002E3 C2002 09 03.33734 01 13 44.81 +03 13 08.8 16.7 V G78 J002E3 C2002 09 03.34919 01 13 47.21 +03 13 58.7 16.7 V G78 J002E3 C2002 09 05.98163 01 43 42.15 +05 55 00.5 d 557 J002E3 C2002 09 05.98245 01 43 42.36 +05 55 03.4 d 557 J002E3 C2002 09 05.98326 01 43 42.62 +05 55 06.4 d 557 J002E3 C2002 09 05.98409 01 43 42.89 +05 55 10.1 d 557 J002E3 C2002 09 05.98490 01 43 43.13 +05 55 13.5 d 557 J002E3 C2002 09 05.98572 01 43 43.37 +05 55 16.8 d 557 J002E3 C2002 09 05.98653 01 43 43.63 +05 55 19.7 d 557 J002E3 C2002 09 05.98735 01 43 43.88 +05 55 23.3 16.9 Vd 557 J002E3 C2002 09 05.98816 01 43 44.12 +05 55 26.8 d 557 J002E3 C2002 09 06.00044 01 43 47.68 +05 56 15.5 d 557 J002E3 C2002 09 06.00422 01 44 10.69 +05 59 26.6 16.0 Rd 946 J002E3 C2002 09 06.00792 01 43 49.76 +05 56 45.1 d 557 J002E3 C2002 09 06.00792 01 44 11.64 +05 59 41.4 16.0 Rd 946 J002E3 C2002 09 06.01284 01 44 12.91 +06 00 01.8 16.1 Rd 946 J002E3 C2002 09 06.01444 01 43 51.51 +05 57 10.5 d 557 J002E3 C2002 09 06.01625 01 43 59.47 +05 56 42.3 16.4 Rc 636 J002E3 C2002 09 06.01796 01 44 00.13 +05 56 48.8 16.5 Rc 636 J002E3 C2002 09 06.02139 01 44 01.07 +05 57 03.0 16.3 Rc 636 J002E3 C2002 09 06.02190 01 43 53.48 +05 57 39.7 d 557 J002E3 C2002 09 06.02310 01 44 01.60 +05 57 08.8 15.8 Rc 636 J002E3 C2002 09 06.03127 01 43 55.88 +05 58 15.9 d 557 J002E3 C2002 09 06.03774 01 44 16.71 +06 02 14.9 16.8 Rm 620 J002E3 C2002 09 06.03780 01 43 57.52 +05 58 40.9 d 557 J002E3 C2002 09 06.04197 01 44 17.51 +06 02 32.2 16.8 Rm 620 J002E3 C2002 09 06.04340 01 43 58.88 +05 59 02.3 d 557 J002E3 C2002 09 06.04513 01 44 18.13 +06 02 45.1 16.4 Rm 620 J002E3 C2002 09 06.04838 01 44 18.75 +06 02 57.0 16.6 Rm 620 J002E3 C2002 09 06.05661 01 44 02.09 +05 59 52.0 d 557 J002E3 C2002 09 06.06127 01 44 03.17 +06 00 09.3 d 557 J002E3 C2002 09 06.23925 01 47 01.69 +06 14 19.2 16.0 Rc 649 J002E3 C2002 09 06.24060 01 47 02.13 +06 14 25.1 15.9 Rc 649 J002E3 C2002 09 06.24250 01 47 02.75 +06 14 33.1 15.8 Rc 649 J002E3 C2002 09 06.24449 01 47 03.43 +06 14 41.8 15.9 Rc 649 J002E3 C2002 09 06.41722 01 47 38.42 +06 25 48.5 16.1 Rd 734 J002E3 C2002 09 06.41924 01 47 38.70 +06 25 54.6 16.2 Rd 734 J002E3 C2002 09 06.42271 01 47 39.24 +06 26 05.9 16.1 Rd 734 G78 is Bill Yeung Desert Wanderer Obs 557 is Ondrejov in Czechia 946 is Jamie Nomen ( Ametella de Mar ) 636 is Essen 620 is Mallorca, Spain 649 is Powell Obs Louisburg Kansas 734 is Farpoint obs, Eskridge, Kansas Of these sites only 557 are professional astronomers ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www.satellite.eu.org/seesat/seesatindex.html
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