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[Asteroidal Occultation] Observational Results from 2012 (actually, since 2011 July 18). 2012 October 19 IOTA meeting, Las Vegas, Nevada David W. Dunham. Occultation of LQ Aquarii on 2011 July 19 mapped the profile of the binary asteroid (90) Antiope. David W. Dunham,
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[Asteroidal Occultation] Observational Results from 2012(actually, since 2011 July 18) 2012 October 19 IOTA meeting, Las Vegas, Nevada David W. Dunham
Occultation of LQ Aquarii on 2011 July 19mapped the profileof the binary asteroid (90) Antiope David W. Dunham, International Occultation Timing Association and KinetX, and many others, from IOTA, IMCCE (Paris Observatory), the SETI Institute, Southwest Research Institute, JPL, Sierra College, etc.
Predicted Path of the Occultation of the 6.7-mag. Star by (90) Antiope
One of the pre-point charts prepared for the 50mm binocular lens-based “mighty mini” systems
MOON Situla rho Ancha phi Hydor 37 chi KR Pre-point line of declination (UT) sigma 58 70 36 54 psi LQ 74 iota 5 Circle tau 69 94 Skat 77 97 66 68
Light curve of the occultation atDunham Station #1 west of Tracy, Calif. The angular diameter of the red giant star caused the disappearance and reappearance to be gradual over several tenths of a second, with different durations at the two events due to different slopes of the asteroid’s surface
Occultation of 8.9-mag. SAO 95144 by (360) Carlova in Carolinas Aug. 15 • Bill Keel recorded a central occultation, 3.3s long, at Univ. of AL, Tuscaloosa • He was near the northern limit, showing that the path shifted ½ path-width north • Scotty Degenhardt ran 7 stations, mostly in the s. part of the path in s.e. AL • His 2 northern stations, n. of center, had short occultations; the others had misses
David Dunham’s stations for the Carlova occ’n The scope symbols show some of the stations that I planned to set up, but it was very cloudy along I-26 . When I reached Spartanburg, SC, I decided to go west on I-85, and found clear sky at Greenville. From there, I deployed 5 stations south near US25, shown by green dots. My stations bracketing the predicted n. limit (the blue line) all were in the actual occultation path. In addition, I ran a 6th station much farther north, at a friend’s place in Hendersonville, NC, but unfortunately the digital recorder there did not write to the SD card correctly, only junk.
Lavonne Occult profile Observers Of the Ginevra Occultation, Sept. 27, 2011
Arachne OW stations 3-9 9 Ernie Iverson’s Line (cloudy) 3
Arachne OW stations 1 & 2 (cloudy) 2 1 Not used
Limovie Lightcurve for my Station #3at Foster Cemetery, e. of Huntsville, TX Analyzed by Scotty Degenhardt
Occultation of SAO 60804, mag. 8.0, by the Trojan Asteroid (911) Agamemnon Thurs. morning, 2012 January 19 This is the best, most valuable asteroidal occultation over the MD/greater Washington, DC region this year We need your help to observe it Following are maps of the path, and several star charts to locate the star in obscure Lynx; Pre-pointing may be needed by most to find the star
Occultation in Mid-Atlantic region at 11:31:40 UT 11s (6:31am & 40s EST) = SAO 138052, spec. type K0 In coastal Mid-Atlantic region (DC, Philadel- phia, Richmond, etc.), Star alt. 24 in az. 299 (northwest, opposite Sun, whose alt. will be -10) View of the Earth as seen from (911) Agamemnon Finder chart, 2 on a side
Map of 2012 Jan. 19th Agamemnon occ’n observers Dunham-4 Dunham-3 Conard Dunham ran a 2nd station between #1 and #3 but the video recorder at #2 failed. Brooks Dunham-1 Tolea Green dots mark positive observations, while red (Brooks) indicates a miss (negative, no occ’n). The green line is the predicted central line while the blue lines are the predicted path limits. The gray lines mark a 10-km zone bracketing Conard’s location where the satellite occ’n occurred.
Steve Conard’s light curve of the Jan. 19th Agamemnon occultation
Sky-plane plot, 2012 Jan. 19th(911) Agamemnon occultation 2 3 4 6 Satellite 8 100 km 9 Agamemnon: Axes 190.6 0.9 by 143.8 1.5 km, PA minor axis -69.3 1.3, center X 4661.6 0.4 km, Y 3113.7 0.6 km; disappearances on right side Satellite plotted as 9-km circle (but it’s more likely about 4 km across) 0.0931 (278 km in the plane) from Agamemnon’s center in PA 93.8
Occ’n of BN Orionis by (57) Melpomene, 2012 March 11, stations