Asteroid Occultation results page with Texas Connections....

 

 

                                   Asteroid Size/Shape Profiles from

                                 Recent Occultations

 

Space probes can image asteroids directly, but this takes years and hundreds of millions of dollars plus the usual delays and funding cuts by Congress. And to date, less than 5 asteroids have been imaged by space probes. Far easier and with a down to Earth cost, asteroid occultations can provide a direct size and shape of asteroids plus the refining of their orbits.  Any person with a telescope, shortwave radio and tape recorder can be on the team to determine the size an shape of these mysterious objects. Nearly 1,000 asteroids have been mapped using the occultation method since 1959 and a sample from Texas observers is shown below.

                                                           

List by Asteroid Number:

 

                    ASTEROID                    DATE OF EVENT               STAR OCCULTED
8   Flora October 29, 2004 TYC 1367-0024
25 Phocaea October 3, 2006 HIP 115725
34 Circe December 23, 2003 TYC 759-636
41 Daphne September 4, 2004 TYC 5181-1999
44 Nysa January 2, 2003 TYC 654:755
54 Alexandra May 17, 2005 TYC 7902-1828
70 Panopaea December 14, 2006 TYC 1231-1469
85 Io June 18, 2003 TYC 530-1006
 95 Arethusa January 15, 2003 TYC 191-774
103 Hera November 22, 2006 TYC 40-819
114 Kassandra December 22, 2003 TYC 4665-1041
208 Lacrimosa December 31, 2006 TYC 1397-1764
216 Kleopatra January 18, 2005 UCAC2 32014147
233 Asterope January 1, 2003 TYC 726-419
345 Tercidina November 15, 2005 TYC 5227-241
350 Ornamenta November 15, 2002 TYC 111-1007
402 Chloe December 14, 2004 TYC 771-1841
441 Bathilde January 10, 2003  
466 Tisiphone January 5, 2006 TYC 1371-938
469 Argentina July 7, 2006 HIP 69577
559 Nanon July 1, 2004 TYC 6288-1139
580 Selene April 30, 2006 TYC 4973-1378
628 Christine December 11, 2005 UCAC2 37141328
654 Zelinda July 29, 2003 TYC 6285-3426
704 Interamnia March 23, 2003 HIP 36189
726 Joella January 3, 2003 TYC 4848-4231
828 Lindemannia November 10, 2002 HIP 13165
856 Backlunda March 8, 2003 TYC 1910-493
978 Aidamina October 24, 2003 HIP 106841
1048 Feodosia November 22, 2005 TYC 1236-138
1263 Varsavia July 18, 2003 HIP 68516

                                     

                

   

        

                                                        

                                         

 

 

 

 

 

 

 

 

 

 

 

 

Note: Asteroid profiles below only show the line of sight view at the time of the occultation. The true size/shape of an asteroid in 3-dimensions cannot be determined from a single occultation.

                           

 

                                               70 Panopaea 2006 14 Dec

The asteroid 70 Panopaea was discovered by H. Goldschmidt on May 5, 1861 from Paris. It occulted a m = 8.6 star December 14, 2006 over a broad track from Texas to Georgia.  Seventeen observers (including 10 from Texas) were lined up to watch Panopaea occult the star under a sky filled with Geminid meteors. The resulting profile showed Panopaea to relatively circular 128.3 x 135.4 km.   

 

                                   

 

 

 

                                              25 Phocaea 2006 3 Oct

The asteroid 25 Phocaea occulted a m = 8.8 star on October 3, 2006 just after IOTA's annual meeting at Mt. Cuba Observatory, Delaware. Over 2 dozen observers from Southern New Jersey to Canada attempted the event with 13 observers recording occultations.  Chords #3 and #4 are Brad Timerson's video-observation showing two dips in brightness. As can be seen by Nugent's drawn asteroid profile to the right of the Occult plot, this double brightness dip could be the result of a graze of one of Phocaea'a mountain peaks or a possible a natural satellite in optical alignment with Phocaea. Phocaea's estimated size  came to 85.5 � 0.9 km x 72.0 � 1 km.  Phocaea was discovered by J. Chacornac on Marseilles on April 6, 1853.

                           

                                       

                                            580 Selene 2006 Apr 30

The asteroid 580 Selene occulted a m = 9.7 star on April 30, 2006 in a path from southern California to southeast Texas.  The predicted ground path had a chance to pass over the Texas Star Party in Ft. Davis, Texas. Selene's size came to 42.7 � 1.3 km x 56.8 � 1.1 km. Selene was discovered by M. Wolf on December 17, 1905.

                              

                        

 

                                           466 Tisiphone 2006 Jan 5

The asteroid 466 Tisiphone occulted a m = 9.2 star on January 5, 2006. Twenty-four observers from Houston to San Antonio attempted the event with 11 observers recording occultations. A south shift of the path caused the Houston area observers to have a miss observation.  to Observer #10 Rick Frankenberger caught Tisiphone's southern portion. The resultant size came to 127.6 � 6 km x 132.8 � 3.4 km.    Tisiphone was discovered by M. Wolf and L. Carnera on January 17, 1901.

 

                                     

   

 

 

                                    628 Christine 2005 Dec 11

The asteroid 628 Christine occulted an m = 11.2 star in Gemini at 1:27AM over northern Houston, Texas. Several observers were unable to see the event due to last minute cirrus clouds moving in over the area. As it turned out if they had a clear view of the target star, they would have seen the occultation. Brian Cudnick's observation (chord #2) shows that the smaller asteroids have irregular shapes that cannot be fitted by a smooth ellipse. Chord #5 (Steve Preston) showed a miss observation, crucial in determining the size limitation of the asteroid. From the observations, Christine's size came to 62.5 x 31.6 km.

Christine was discovered by A. Kopff of Heidelberg, Germany on March 7, 1875. Christine is the earlier feminine form of Christian, Greek for "anointed Christian."

 

                               

                                       1048 Feodosia 2005 Nov 22

The asteroid 1048 Feodosia lies in the main belt zone IIb along with  1 Ceres (the largest asteroid known). On November 22 it occulted a m = 11.9 star in the constellation Aries as it passed the point in its orbit just crossing the ecliptic (the Earth's orbital plane). The occultation path was over the southern United States and three experienced observers in Arizona (Jim Stamm, Derald Nye and Jim McGaha) all observed the event (McGaha had a miss), and Richard Nugent observed it from Texas. The resultant size/shape is shown below and an elliptical size for Feodosia of  approx 80 x 38 km was determined.

1048 Feodosia was discovered by K. Reinmuth, Heidelberg, Germany on November 29, 1929 and is named after the Crimean city Feodosiya in the Ukraine. 

 

                              

 

 

                                        345 Tercidina 2005 Nov 15

The occultation of a m = 8.9 star by the  asteroid 345 Tercidina was observed by 5 observers in Northern California/Nevada on November 15, 2005. Paul Maley had 2 stations set up in California with C. Chleborad at Grass Valley and A. Gallagher at Weimar. Both stations had occultations of 7.93 sec and 6.8 sec respectively. Richard Nugent's observation (chord #5) was just south of the path and had a miss. This important 'miss' chord placed a size limitation on Tercidina to the south.

Tercidina was previously observed by over 70 stations in Europe in September 2002 deriving a shape of 110 x 91 km. The current size shows a larger size for Tercidina in part due to the lack of stations on the north side of the path and in part due a different orientation angle.  Tercidina was discovered by A. Charlois on November 23, 1892.          

 

                                 

 

                                                          54 Alexandra 2005 May 17

The "C" class main belt zone asteroid 54 Alexandra occulted a m =8.4 star in the early morning hours of May 17, 2005.  It was observed by observers in Baja Mexico, Texas and Oklahoma at very low altitudes. The geometry of Alexandra's orbit and Earth was such that Alexandra was moving very slowly across the sky at only 6.4"/hour. Alexandra is a large Main Belt zone IIb asteroid in the Ceres family. Its slow movement allowed for occultation lasting 1 minute and longer near the center of the path.

At Peter Armstrong's fixed location at Limpia Observatory in Ft. Davis, Texas, he caught a brief 0.9 second event, placing him on the extreme edge of the asteroid path, while Mitch Brumbelow, Richard Nugent and Chad Eellington's occultations (chords 3, 2 and 4) exceeded 60 seconds each!

Alexandra's egg shape comes to a smooth oval 159.9 x 132.4 km size with an uncertainty in the shape of less than �3 km.        

54 Alexandra was discovered by G. Searle on September 10, 1858 at Albany. Alexandra is Greek for man's defender, Alexandria is also a city in Egypt, 20th Century Greek Princess, 19th century British Queen and Russian Empress, 18-19th century Russian Emperor, 13th century Scottish King, Italian Pope, Spanish Pope, 12th century English philosopher Alexander of Hales, and 13th century Russian hero and saint Alexander Nevsky.  

                             

                                                                       216 Kleopatra 2005 Jan 18

The cigar shaped asteroid 216 Kleopatra occulted a star over southeast Texas and was observed by Paul Maley from NASA-JSC. With his equipment (C-8, Watec camera, and Collins I3 piece), he was able to detect a 0.31 magnitude drop recording a 5-second occultation. No other observers had occultations.

IOTA astronomers were the first to determine that Kleopatra had a highly elongated profile (261 km x 60 km) from an occultation on January 19, 1991. Later observations using adaptive optics by the 10-meter Keck telescope on Mauna Kea in Hawaii and radar images from the Arecibo 1000 foot radar dish in Puerto Rico confirmed the cigar shape.

    

           

 

                                                              

                                                                    402 Chloe 2004 Dec 14

The large "C" class asteroid 402 Chloe occulted the m = 11.1 star TYC 771:1841 on December 15, 2004 from southern Arizona to northern Florida. Veteran occultation observer Roger Venable set up two stations in northern Florida, he had one hit and one miss (chord # 4),  Richard Nugent drove to Buffalo, Texas and video recorded a 8.8 second event, and Jim Stamm in Tucson timed a visual occultation of 10.6 seconds. Long time time IOTA member, Bert Stevens made his first successful occultation observation but has not provided his data yet, due to his uncertainty in the timings.

The unexpected elongated shape of 402 Chloe is calculated as 39� 5.9 km  x  90 4.3 km as seen below, and warrants further study.

 

                               

402 Chloe was discovered by A. Charlois at Nice, France on March 21, 1895. Chloe is the shepherdess in the Greek romance Daphinis and Chloe in Greek means "young green shoot."

                                                             8 Flora 2004 Oct 29

The largest asteroid in the Flora zone, 8 Flora occulted a 9.4mag star on October 29, 2004. Six stations recorded the event including a remote station set up by IOTA President David Dunham. IOTA Vice President Paul Maley captured a short 1-second  occultation defining the southern edge of the asteroid. The profile of Flora is published in the March 2005 issue of Sky and Telescope, page 71. See the article about the Flora Asteroid Clan which includes an animation of how asteroid families may have formed.

                                                      

8 Flora was discovered by J R Hind on October 18, 1847 in London and is named for the goddess of flowers and gardens, wife of Zephyrus.

      

 

                                                                            41 Daphne 2004 Sep 4

The large "C" class asteroid 41 Daphne occulted the m = 11.4 star TYC 5181:1999 on September 4, 2004 over west Texas. Veteran occultation observer Peter Armstrong and McDonald Observatory astronomer Shannon Rudine attempted it from Ft. Davis, Texas only to have last minute passing clouds foil their observation. Richard Nugent drove further west to Valentine, Texas and video recorded a 12.0 second event, the only successful observation. Nugent's site had passing clouds also, but they cleared in his field of view of his video monitor just 20 seconds prior to the occultation !!  The small magnitude drop of 0.7 was easily seen on his video. The 12 second occultation corresponds to a 123 km chord (which is not necessarily a diameter) across the asteroid, much smaller than the 174 km size predicted from photometric methods.

41 Daphne was discovered by H. Goldschmidt in Paris on May 22, 1856. Daphne is the daughter of Terra, and she changed into a laurel tree when she asked the gods to protect her virginity from the attraction of Apollo.

                                                                             559 Nanon 2004 July 1

The asteroid 559 Nanon occulted the m = 8.6 star TYC 6288:1139 over southern California on July 1, 2004. This was the 3rd asteroid event observed by  the attendees of the 24th annual meeting of IOTA in the span of a few days with 5 events in California during the same 10 day time interval. Richard Nugent and Hal Povenmire originally set up about 15 miles east of Yucca Valley, CA but as occultation time approached some clouds moved in and they relocated in a Walgreens parking lot in Yucca Valley. Art Lucas also happened to be set up in Yucca Valley and hence their chords are overlaid upon each other (#'s 5 and 7). Paul Maley observed from Lucerne Valley, CA and had a miss. Due to the lack of roads and the terrain, only the northern part of asteroid could be covered.  Nanon's estimated size from the observations is 88 18 x 56 km. The large deviation in the major axis of the size is due to the lack of observations on the south side of Nanon. 

559 Nanon was discovered by Max Wolf of Heidelberg, Germany on March 8, 1905. It is the name of a operetta by 19th century German-Austrian composer Richard Genee.

 

                   

                                                                                                                                                                                      

 

                                     208 Lacrimosa 2003 Dec 31

 

The "S" class asteroid 208 Lacrimosa occulted the m = 9.0 star TYC 1397-1764-1 in the early morning hours of December 31, 2003. Fourteen observers attempted this event from Southeast Texas with 4 observers getting occultations, including 15 year old Beth Turner from The Woodlands, Texas; she videorecorded a 5.03 second occultation, an IOTA record for the youngest person to grab an asteroid occultation.  Paul Maley video recorded a 5.62 second occultation, while Ken Drake visually timed a 2.5 second event, Paul Sventek visually timed a 5.0 second event, and Tim Kenyon visually timed a 4.8 second event from North of Austin.

Brian Cudnick (observer # 6) reported seeing a possible "twinkle" event from his location, indicating a possible graze by the asteroid, however since his location was south of the known southern limit, his observation was likely the result of seeing conditions or scintillation effects.  Richard Nugent video recorded an undisputable miss under excellent seeing conditions from north of Cudnick's location, this verifies Cudnick was well south of the asteroid's path. However Cudnick's observation doesn't rule out a possible tiny asteroid moon or other piece of debris in the line of sight.  Lacrimosa's estimated size from the positive events came to 40.8 km x 48.8 km, very close to previous photometric estimates of 41 km.  

208 Lacrimosa was discovered on October 21, 1879 by J. Palisa, Pola. The famed asteroid orbit computer, Schmadel has reported that Lacrimosa could have only been observed four times by Palisa, making the recovery extremely difficult.

 

                       

 

 

 

                                            34 Circe 2003 Dec 24

 

The "C" class asteroid 34 Circe occulted the m = 11.8 star TYC 759-636-1 in the early morning hours of Christmas Eve 2003. This was a difficult observation since Circe was also at m = 11.8 at the time of the occultation, causing a small 0.8 magnitude drop in brightness. Fortunately for Richard Nugent, he had nearly idea observing conditions: dark sky location, and cold, crisp steady air. He video-recorded an 11.7 second occultation from 25 miles north of the predicted center path. The disappearance was plainly visible on Nugent's camcorder monitor, but the reappearance was gradual lasting perhaps 1 second. This gradual brightening in the target star could mean a possible double star or perhaps the integrated effects of the noise attributed to the image intensifier used to make the observation.  The 11.7 occultation was the maximum expected for 34 Circe due to its previously estimated size, thus a 25 mile north shift in the path had occurred. Paul Maley and a few other observers also attempted this event but had equipment problems. Thus, with a single observation, no new size/shape data can be attained.

34 Circe was discovered on April 6, 1855 by J. Chacornac of Paris. Circe was the enchantress, daughter of Helios and Perse, celebrated for her knowledge of magic and herbs.  According to legend, Circe had a son named Telegonus by Odysseus; she later changed the companions of Odysseus into pigs, they were later transformed into humans. 

 

                                      114 Kassandra 2003 Dec 21

              

The Main Belt Zone II type "T" asteroid  114 Kassandra occulted a m = 11.8 star on December 21, 2003 over the United States.  The predicted path shifted nearly 3/4  pathwidth north, far exceeding the prediction made by IOTA astronomer Steve Preston. It is unclear why there was such a large shift, when the prediction showed a small possible shift of only 1/4 pathwidth. In the profile of Kassandra below, Observers 3 (Paul Maley) and 4 (Richard Nugent)  had a miss observation placing a limitation of the size of the asteroid. Observer 1, Art Lucas video recorded a 6.0 second occultation from his home observatory in Stillwater, OK. Doug Kniffen recorded a 3.0 second occultation visually using a 16" telescope. Several observers in Canada attempted this one, but last minute clouds foiled their observations.

Although in the plot below, the fitted ellipse shows a 81 km size, it is known that Kassandra is at least 118 k in size from photometric observations. 

Kassandra was discovered by C. H. F. Peters on July 23, 1871. Kassandra was the most courted, of the 12 daughters of Priam and Hecuba of Troy who requested, and was granted the gift of prophesy by Apollo. When she failed to love him he effected a curse that made her prophesies not credible or believed. 

                           

                                

                                                                             978 Aidamina 2003 Oct 24

              

The Main Belt Zone asteroid  978 Aidamina occulted a m = 8.3 star on October 24, 2003 over the United States.  Although no observers successfully observed Aidamina on the north side of the occultation path, a good profile indicating Aidamina's size was found to be approximately  88 x 68 km.  Aidamina occulted a star earlier this year across Spain on July 26, 2003 in which its size was determined to be 90.3 x 54.4 km in reasonable agreement with this occultation.  The predicted path shifted 0.3 pathwidth north, within the margin of error from the initial  prediction made by IOTA astronomer Steve Preston. In the profile of Aidamina below, Observers 4, 5, 7 and 9 had a miss observation placing a critical limitation of the size of the asteroid.

Paul Maley observed this event from the Guadalupe Mountains of west Texas and recorded a 4.92 second occultation while Richard Nugent observed a 2.05 second occultation from Balmorhea, Texas, being very nearly at the asteroid's southern edge. Despite ideal observing conditions, "Murphy" was around with Nugent's observation.  Nugent's video observation was nearly ruined by a passing truck whose high beam headlights seemed to be "timed perfectly" to be shining on his telescope during the 2 second occultation as it passed him by at 5 mph. Richard and his parents (who accompanied him) failed to steer away the oncoming truck, and the video recording had substantial glare only during the 2 second occultation. Fortunately this was a relatively bright star and the times of disappearance and reappearance were able to be extracted from the video.  Another confirmation of the old saying, "If anything can go wrong, it will."

Aidamina was discovered by S. I. Belyavsky on May 18, 1922 in Simeis. The discovery was confirmed by Max Wolf on May 30, 1922 in Heidelberg, Germany. It was named after the astronomer's friend, Aida Minaevna.

                               

        

                                                                                   654 Zelinda 2003 Jul 29

 

The "C" class Phocaea group asteroid 654 Zelinda occulted a m = 11.5 star on July 29, 2003. Observers were stationed across the US from California to North Carolina anticipating this event however poor weather conditions and those nasty "partly cloudy" forecasts forced observers to relocate at the last minute. Richard Nugent constantly moved around west of Oklahoma City, Oklahoma to find a clearing in the clouds. There were seemingly large breaks in the clouds one moment, then 10 miles further down the road, it was completely overcast. After driving for 3 hours, Nugent finally pulled over on Hwy 33 northwest of Oklahoma City where is was completely overcast and took a nap. His alarm went off 1 hour before the event, whence the sky had cleared ! He set up his video system and 4" Meade 2045D and Supercircuits PC-164 camera and located the target star in constantly changing sky transparency conditions. The faintness of the star along with its low altitude (30�) made it difficult to see on the video monitor. At nearly the predicted time, the star was clearly visible and he recorded the asteroid taking 9.72 seconds to drift across the star.

Paul Maley went to Bluebird Observatory in central Oklahoma, owned by IOTA treasurer Art Lucas and they had similar sky conditions. Rather than drive to an alternate site to observe the occultation, Paul stayed at Art's place and the sky opened up 45 minutes before the event. Both video recorded occultations: Art using a C-14 and Watec camera got a 9.2 second occultation, while Paul used a C-8 and he calculated a 9.24 second occultation.

654 Zelinda was discovered by A. Knopf in Heidelberg, Germany on January 4, 1908. It was named after the niece of astronomer Camille Flammarion and daughter of his sister Berthe.   Flammarion was the "Carl Sagan"  and one of the greatest popularizers  of astronomy in the 19th century. 

 

 

 

                                                                   1263 Varsavia 2003 Jul 18

 

From Washington state to southern California, over 30 observers had successful timings of the Main Belt asteroid 1263 Varsavia occult the m = 6.5 star HIP 68516 (SAO 100819). Due to the high inclination of Varsavia's orbit (29�), the 80 km wide path was mainly north-south. The occultation was very short, only just a little over 2 seconds for observers situated near the path's center. Richard Nugent observed this event near Grass Valley, CA and got a 1.92 second occultation.  This bright star showed very well on Nugent's video as excited onlookers watched the star blink out and 2 seconds later blink back on. Following the occultation, the next day,  the International Occultation Timing Association, IOTA, held its 21st annual meeting at Sierra College in Rocklin, CA hosted by astronomer Dave Kenyon of the Sierra College Astronomy Dept.  Videos were shown at the meeting of the previous nights Varsavia occultation and observers discussed observing and data reduction techniques.

Note the wide inconsistency of chords in this profile below. This occultation, being only 2 seconds in duration, caused many visually observed chords to have larger errors relative to their lengths.  A total of 78 observers timed this occultation, which included 51 occultation timings and 27 misses, thus being in the top observed asteroid occultation events in history

 

1263 Vasavia was discovered on March 23, 1933 by S. Arend at Uccle, Belgium. Vasavia is the Latin name for Warsaw, Poland.

                  

        

 

                                                                

 

                                                                             469 Argentina 2003 Jul 7

 

Observing from the mosquito infested swamps of Central Florida, Richard Nugent successfully timed a 13.5 second occultation of the m=8.7 Hipparcos star HIP 69577 by the asteroid 469 Argentina.  (Argentina was named after the South American Country of the same name). Only one other observation was made of this event, by Chris Stephan from Robert Clyde Observatory in Sebring, Florida. Although this was a bright star occultation, and could have been seen in a pair of 7 x 50 binoculars, the magnitude drop was small, only 1 magnitude. This is due to the target star HIP 69577 being a triple star system with the components just 20" away. Nugent was able to resolve the duplicity of the target star in his video using a 4" Meade SCT telescope and his low light video camera, the Supercircuits PC-164C, along with the Collins I3 image intensifier. Stephan's (CS) and Nugent's (RN) chords came out to 91 and 83 km respectively as shown in the diagram below. 

                                                           

469 Argentina was discovered on February 20, 1901 by L. Carnera in Heidelberg, Germany. It was named after the South American nation of the same name. Argentina is also the name of a river in Italy.

 

 

                                                                                  85 Io 2003 Jun 18

 

Observing from his house, Paul Maley recorded a 23.98 second occultation of the m = 11.3 Tycho-2 star 530-1006 by the "C" class asteroid 85 Io. Paul used a Celestron-8 telescope and the highly sensitive Watec video camera along with a Collins I3 image intensifier. This corresponds to a chord of 133 km at the distance of the asteroid.  This was an extremely difficult occultation -  Houston had  a slightly hazy sky (compared to the usually very hazy skies this time of year) and the 81% illuminated Moon was just 24 degrees away. Richard Nugent also attempted to observe this occultation but had problems with the lights being just 3 miles from downtown Houston.

At the time of the occultation, 85 Io was 1.43 astronomical units (AU's)  from Earth. 85 Io was discovered on September 19, 1865 by C.H.F. Peters and he named the asteroid Io after the daughter of the river god Inachus, son of Oceanus who apparently changed into a cow and later escaped Argus through the Ionian Sea to Egypt where she became Isis.

   

                                                                    704 Interamnia 2003 Mar 23       

 

The large "F" class asteroid 704 Interamnia occulted a m = 6.6 star on March 23, 2003. This very favorable occultation path was visible directly over Tokyo, Japan and then crossed the Pacific ocean over the Big Island of Hawaii. International cooperation made this the most successful occultation this year with 35 observers timing the event and obtaining chords. In Tokyo, the effort was led by IOTA/JAPAN astronomer Dr. Isao Sato, while the effort in Hawaii was led by IOTA President Dr. David Dunham and IOTA Vice-President Paul Maley. The resultant asteroid profile is shown below and this event gave astronomers the most accurate size/shape of Interamnia in recent years.

Interamnia was discovered October 2, 1910 by V. Cerulli in Teramo, Italy. It was the ancient name of the discoverer's birthplace, Teramo. 

                   

 

                                                                  856 Backlunda  2003 Mar 8

 

The occultation of a m=11.4 star by the asteroid 856 Backlunda was successfully times on video by 2 observers located in the Ft. Davis, Texas area and 2 observers in the Eastern USA. IOTA President David Dunham left his home in Maryland and drove several hours through construction and detours to finally set up and make a 3.8 second video observation near Smith Crossroads, Va. Roger Venable set up two stations, one with a 10.1 second occultation at Dobson, North Carolina and the 2nd station had a failure due to a VCR not turning on as programmed. In west Texas, Richard Nugent and Peter Armstrong video taped the event under constantly changing haze/cloud cover. Peter Armstrong observed his 3rd successful occultation from his personal observatory in Ft. Davis while Richard Nugent drove 10 km south of Marfa, Texas, site of the famous "Marfa Lights." The resulting profile of 43 x 60 km is in reasonable agreement with Backlunda's previously estimated size of 52 km. After the occultation, Nugent by mistake left his Sky Atlas 2000.0 charts on the road side but came back the next day to find  them gone, despite his GPS measurement of the site. Later that day he received a phone call from a Marfa, TX resident - they  found his atlas - in pages scattered all over the roadside due to high winds.
 

856 Backlunda was discovered by S.I. Belyavsky, Simeis on April 3, 1916.  It was named after the Swedish born Russian astronomer Johann Oskar Backlund. A lunar crater bears the same name.

                                    

                                                                       

                                                                     95 Arethusa  2003 Jan 15

 

The occultation of  a  m = 10.9 star by the "C" class asteroid 95Arethusa turned out to be another race for clear skies over the valley of South Texas. Paul Maley flew to McAllen, Texas. With several other observers he was planning on staying in McAllen. But clouds soon moved in and the group was forced to drive (3 car caravan) north to reach clear skies. Upon setting up his Collins image intensifier on a Celestron 8, Paul noticed it wouldn't turn on. So he switched to observing the asteroid visually and recorded a 12.1 second occultation. Fortunately the target star was less than 1/2 degree away from the zero magnitude star Procyon, so locating it was easy. Read more about Paul's adventure here.

Richard Nugent drove to a site originally 20 miles north of Maley's and arrived under overcast skies. He set up his 10" LX-200 and desperately tried to locate alignment stars during brief breaks in the clouds. After doing so he acquired the target star and asteroid on video as the sky opened up. A Hidalgo County Sheriff  drove up and asked what he was doing, and he explained the nature of his "suspicious looking equipment". The Sheriff stayed to watch the occultation and later was treated to views of M42, Saturn and Jupiter under excellent seeing conditions. Richard video recorded a  12.1 second occultation also. Chris Stephan in Sebring, Florida made a visual timing of Arethusa. His chord turned out to be overlapped up with Nugent's video observation, and this shows how video/visual timings don't always agree.

The 3 timings of Arethusa give an size of at least 172 km, about 20% larger than its size obtained from previous indirect methods.

95 Arethusa was discovered way back on November 23, 1867 by R. C. T. Luther in Dusseldorf. Arethusa was a Nereid nymph member of the Hesperides, attendant upon Artemis who changed her into a fountain when pursued by the river god Alpheus. 

                                                        

 

 

                                                                   441 Bathilde  2003 Jan 10 

 

 

Another bright star occultation occurred over the Houston San Antonio on January 11, 2003. The star magnitude was m = +7.7, bright enough to see in binoculars. Again Houston and San Antonio were clouded out, but one lucky observer, Joe Dellinger at the George Observatory 55 miles south of Houston, saw a 7.7 second  occultation (chord #6) . Along with Roger Venable's 2 stations (one video: chord #2, one visual: chord #4) and others from Europe, the preliminary profile is shown.

 

441 Bathilde was discovered on December 8, 1898 by A. Charlois in Nice, France.            

 

                          

 

                                           726 Joella  2003 Jan 3

 

Observing near Cash, Texas, Paul Maley made a successful observation of the small asteroid Joella as it occulted the 10.9 mag Spectral type "F" star TYC 484842317. Paul used  C-8 and the Supercircuits PC-164C video camera and a f/6.3 focal reducer to capture a 2.3 second occultation with no indication of secondary events (possible asteroid moons).  No other observers reported an event with this asteroid.

 

 

                                                            44  Nysa  2003 Jan 2

                                

The Nysa occultation was video recorded by Peter Armstrong in Ft. Davis, Texas and Richard Nugent  in Jai, New Mexico on 2003 Jan 2.  Several other observers tried this one but due to the low magnitude drop, it was extremely difficult to see. These chords show an ellipsoid shape.  Nysa's minimum estimated size is 43.9 x 50.1 km from the projection of these 2 chords, however, minor planet investigators have reported a much larger shape of 115 x 70 x 55 km from its light curve, thus Nysa could very well be highly elongated.  Nysa is also the largest asteroid of a family consisting of 381 members situated in the range of 2.419 - 2.477 AU's from the Sun. 

This event marked 3 successful occultations in 2 nights by Richard Nugent. Read more about it here.

 

 

 

                                          233 Asterope  2003 Jan 1 

The "T" class asteroid 233 Asterope was video recorded by Paul Maley south of Houston  and Richard Nugent at Carrizo Springs, Texas. Maley had to move his location south at the last minute situating his position nearer to Nugent's. The two chords obtained cannot denote a shape of Asterope, but places its size on the order of 106 km or more, in agreement with the size derived from photometric techniques.

233 Asterope was discovered on May 11, 1883 by A. Borelly, Marseilles. Asterope is also one of the stars in the Pleiades.  

Observer #1 is Maley and #2 is Nugent.

 

                        

 

                                     

 

                                   350 Ornamenta  2002 Nov 15

 

The occultation of a m = 9.8 star by 350 Ornamenta was observed by 14 people from South Texas to Los Angeles. The resultant estimated size of 94 x 116 km is close to its predicted size. In Texas, Richard Nugent (chord #13) and Paul Maley (chord #6) coordinated together and observed the occultation stationed 58 miles apart., equally spaced from the predicted center line. A number of other observers in the Los Angeles area observed the event mostly from their homes. The location of their homes resulted in a number of crowded chords (#'s 2, 3, 5 and 6) near to the north side of the asteroid duplicating results. This shows the importance of teamwork in an occultation effort to space out observers to get as many well spaced chords as possible. Just like searching for a golf ball in the rough, spreading out gives a better chance of finding it.  Also note that chord #13 (Nugent) is a accurate video observation, yet it does not appear to fit the average shape very well. This shows that Ornamenta, like many asteroids is irregular in shape and not a perfect ellipsoid or spheroid.

350 Ornamenta was discovered on December 14, 1892 by A Charlois, Nice France. Named for the Mariner Hornemann, of Holland, "whose son is a very zealous member of the Societie Astronomique de France."  

                     

 

 

 

                                                         828 Lindemannia  2002 Nov 10

 

 The effort to observe the occultation of a m = 5.4 star by the asteroid 828 Lindemannia over south Texas was organized by Paul Maley of the NASA Johnson Space Center Astronomical Society in Houston, Texas. Over 100 observers were recruited at several monthly astronomy meetings by Richard Nugent. Clouds foiled the occultation for most of the observers, but 12 observers saw the star and the occultation and the resulting profile is shown below: (Size = 51.5 x 51.4 km).

                           

                       

Observer #12, Becky Ramatowski was less than 2 km from the south limit of the asteroid and had a miss. Her very crucial observation puts a size limitation on Lindemannia. Pedro Valdez Sada, came in from Mexico to observe Lindemannia and also had a miss south of Becky Ramatowski.

See Richard Nugent's 25-second video clip of the Lindemania Occultation right here.

828 Lindemannia was discovered on August 29, 1916 by J. Palisa, in Vienna, Austria. Named after the inventer of the electrometer Alolf F. Linemann. An island of the same name exists off Australia.  

 

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