The large asteroid (45) Eugenia will eclipse the 5.7-mag. star SAO 94227 Sat. evening, 2008 March 8, in Mexico and its moons will eclipse it in the southern USA - New 2008 March 1, 12:30 am EST
We need YOUR help to map the asteroid and its small moons
The eclipse (called "occultation" by astronomers) by either Eugenia or by its moons can be seen with binoculars, if you can find the star not far from Aldebaran in Taurus
This Web page will be shut down Friday, March 7, by 5pm EST and will not be available again until late Sunday evening, March 9; after March 1, it will be better to see the latest information about this event here at IOTA's asteroidal occultation site for N. America
The occultation by Eugenia, about 215 km in diameter, will last up to 12 seconds in its path crossing northern Mexico over Loreto, Baja California sur; Torreon; Saltillo; and Monterrey. The occultation by Eugenia's larger (about 13 km) moon, Petit- Prince, will last about 0.7 second in a path passing near or possibly over Shreveport, Louisiana; Dallas, Ft. Worth, and Lubbock, Texas; Albuquerque, New Mexico; Las Vegas, Nevada; and Fresno, California. The occultation by Eugenia's smaller (about 6 km) moon, S/2004(45)1, will last about a third of a second in a narrow path passing near or possibly over Corpus Christi, San Antonio, and El Paso, Texas; Nogales, Arizona & Sonora; and San Diego, California, but its path is more uncertain than that of the larger moon. The star, also known as HIP 23043, is in Taurus about 5 degrees east of Aldebaran at J2000 RA 4h 57m 22.3s, Dec +17 deg. 09' 13"; finder charts of different scales to help locate the star can be found on Steve Preston's prediction page for the event. A full-sky star chart and other simple charts will be posted on IOTA's asteroidal occultation site for N. America. The International Occultation Timing Association (IOTA) needs as many observers as possible to try to time the occultations by Eugenia and its moons, to better determine their sizes, shapes, and relative orbits. If you are anywhere near the paths described above, you are encouraged to watch or record SAO 94227 from 5:42 to 5:45 UT (Universal or Greenwich Mean Time) of March 9, or, in local time, Saturday evening, March 8, at 9:42 to 9:45 pm PST, 10:42 to 10:45 pm MST, and 11:42 to 11:45 pm CST. The Petit-Prince occultation might even be seen at low altitude in the Florida panhandle early Sunday morning, March 9, from 12:42 to 12:45 am EST. In Mexico, Kerry Coughlin, e-mail BajaKerry@gmail.com, is coordinating observations in Baja California while Pedro Valdez Sada, e-mail pvaldes@intercable.net, is coordinating them in Nuevo Leon and nearby areas of northeastern Mexico. David Dunham, e-mail dunham@starpower.net, is coordinating plans for the observations of the occultations by the Eugenian satellites. Especially for the satellites, we need many observers set up at pre- determined distances across the path in a way that will cover the uncertainty zone of the path, which is considerably wider than the path itself. We need the locations of observers who will try it from home locations or from fixed observatories so that mobile observers can fill the gaps in the coverage that the fixed-site observers can provide. The interactive Google maps on Derek Breit's Global Web site here will be used for this planning, along with other tools. At the moment, we only have a Google map set up for Eugenia, with offset distances that can be used to determine lines for the predicted occultations by the satellites, but early next week we plan to have separate predictions and interactive maps (that can be zoomed in for great detail, including aerial photography of many areas) for the satellites. Derek Breit's Global site also includes a list of stations and cities in and near the predicted path, listed in order of distance in kilometers from the predicted central line (distances north of the line are considered as negative), and for each gives the predicted time of the center of the occultation, the probability that an occultation will occur, and the local circumstances (mainly in this case, the altitude above the western horizon) of the event. To help publicize this event, and provide basic information and observing tips for timing it, Pedro Valdez Sada has prepared a 3.2-megabyte Power Point file in Spanish here and in English here (translated by Dunham, Jose Guzman, and Pedro Valdez Sada). It concentrates on observing the occultation by Eugenia in Mexico; more information and maps will be provided soon for the satellite events in the U.S.A. on IOTA's asteroidal occultation site for N. America. More information on timing occultations is here. Much information about observing occultations of all types is in "Chasing the Shadow: The IOTA Occultation Observer's Manual" available for free here. Much information about asteroidal David Dunham, IOTA, 2008 March 1, 12:30 am EST qqqqAsteroidal Occultations (Eclipses of Stars by Asteroids) zzzz coordinate Steve Preston's prediction page message to Paul Maley, and others who are encouraged to observe this: Many thanks for this, your stations near Las Vegas; it will be good to get some observers active there, since little has happened there occultation-wise since Walter Morgan moved from there several years ago. But so far we have only 3 stations for this good event, all fairly close to the center of this wide path crossing the USA from N. Carolina to s. Mo., s. Kans., to Las Vegas and central Calif.; I hope more will try it, to give better coverage across the path so that the size and shape of Panopaea can be determined, so I'm copying this to additional possible observers not on the e-group list. Unfortunately, the Astro Meteo weather forecast is poor for North Carolina, making it too risky for me to make the long drive there, but some breaks in the clouds are forecast, so I hope that some other observers besides Mike Fulbright might try it (he at Cary, NC and you are the only ones near the path who have declared plans to observe it). Thick clouds are also forecast over Tenn. and Kentucky, but mostly clear skies, with just small patches of clouds here and there, are forecast for most of the rest of the path from s. Missouri to cen. Calif. The event will occur at 5:04 UT (12:04 am EST of Jan. 12) in N. Car. to 5:07 UT (9:07 pm PST Jan. 11) in Calif. A central occultation will last 10 seconds with an easily- seen 2-mag. drop. The star is 11.1-mag. TYC 2501-00817-1 at J2000 RA 9h 46m 49s, Dec +30 deg. 34' 23", about a deg. northeast of 15 Leonis just north of the Sickle. Detailed finder charts are here. The distances of some potential observers in the path are listed below; more details for them [probability for an occultation, the predicted time of closest approach at the station, and altitude of the star (ranging from almost 60 deg. in e. N.C. to about 25 deg. in Calif.)] are given on Derek Breit's site list for the event. Dist. + is north, - south from center +99 ** 1-sigma n. limit +94 Springville, CA J. Sanford +80 Springville, CA Chandler +62 ** predicted northern limit +56 Rolla, MO J. Senne +46 Cuesta College, CA +38 Santa Margarita, CA R. Genet +36 Iola, KS T. Campbell +12 Las Vegas north station CONFIRMED +7 Ridgecrest, CA C. Evans -2 Wichita, KS -4 Cary, NC M. Fulbright CONFIRMED (may be cloudy) -24 Las Vegas south station CONFIRMED -34 Springfield, MO -41 Kinston, NC J. Faircloth -48 s. Kentucky mobile S. Degenhardt CONFIRMED but cloudy? -57 Lockwood Valley, CA S. Edberg -62 ** predicted southern limit -84 Carpenteria, CA E. Edwards -87 Stedman, NC J. Horne -98 Castaic, CA F. Anet -99 ** 1-sigma s.limit & Bartlesville, OK J. Grismore -139 Altadena, CA G. Lyzenga CONFIRMED Good luck with your observations! David At 07:26 PM 1/10/2008, you wrote: >The tentative locations for the two sites are modified from my first >email. They will be at 12km North and 24 km south. > >Paul Maley David Dunham, 2008 Jan. 11, 1:30 pm EST Phones home 301-474-4722; office 240-228-5609; cell 301-526-5590 office e-mail david.dunham@jhuapl.edu with Blackberry for mobile use home e-mail: dunham@starpower.net .
Asteroidal Occultations (Eclipses of Stars by Asteroids)
Help us measure the sizes and shapes of asteroids by timing their eclipses, or occultations, of stars
"Super Monday" 2008 January 14, at least 5 asteroidal occultations in the USA
The Nov. 19th Nealley, Nov. 10th Eunomia, Nov. 11th Bilkis, and the Oct. 29th Gerlinde occultations were each observed from one station, and the Nov. 16th Zelinda and Metcalfia events each from 2 stations, as far as we know now
General information on how you can find the next asteroidal occultations near YOUR location is given
Updated: 2008 January 14 UT, 1h UT
Please help us measure asteroids by observing their occultations. The next reasonably good North American occultations are described below. Sorry that I don't have time to provide hot links to the web pages for these events mentioned; just copy and paste them into your Web brouwser. Super Monday, January 14, has at least five asteroidal occultations in the USA, all crossing the Mid-Atlantic States with fairly good weather forecasts, but most of the paths also cross other parts of the USA. Please help us measure the sizes and shapes of these objects, and check for possible close duplicity of the star or of the asteroid. Any observations you can make, visual or video, will be greatly appreciated; possible timing methods are described at http://iota.jhuapl.edu/timng920.htm . Especially video equipment is available for loan, if you could attempt an observation with your telescope at your home. The main 5 events are summarized below, then some more detailed information is given about them. Please let me know your plans for the Winchester and Phocaea occultations, the better events of the lot, so I can select sites to avoid duplication of your observation and obtain better coverage to better determine the parameters of these asteroids. Finder charts of different scales and other details can be found at Steve Preston's Web page that is given for each event. 1. At 4:10 am EST, in North Carolina & s. Virginia, a 10.4-mag. star near delta & epsilon Ophiuchi will be occulted by the large asteroid 747 Winchester. Astro Meteo forecasts clouds in the east but decreasing to clear towards the mountains, and clouds again in the mountains, and over e. Tenn., southwesternmost Va., W.Va., & e. KY. The star will be 13 deg. high in the east where the path crosses I-95; clouds are expected east of there, and the star will be lower towards the west. I plan an expedition from the DC area, but will cancel if the next forecast at 11 pm isn't better. The star, TYC 5041-00769-1, is at J2000 R.A. 16h 10m 24.0s, Dec. -4 deg. 53' 46"; Preston's Web page is at http://www.asteroidoccultation.com/2008_01/0114_747_12386.htm . Possible stations are listed below, none yet confirmed. distance in km from center 192 N ** 1-sigma n. limit ** 150 N Richmond, VA area 120 N J. Goss, Fincastle, VA 107 N ** predicted northern limit ** 105 N D. Dunham mobile 92 N M. Good, Roanoke, VA 45 N W. Warren mobile 0 D. Dunham remote, central line 49 S M. Fulbright, Cary, NC 107 S ** predicted southern limit ** 115 S R. Harvey, Concord, NC 192 S ** 1-sigma s. limit ** Note that on Derek's Web site for this event, positive distances are south. Observers who have too many trees or other obstructions for this relatively low-altitude event may need to find a nearby field, at a school or park, etc. 2. At 11:08 to 11:10 UT (3:08 am PST to 6:10 am EST), a 13.5-mag. star east of kappa Virginis will be occulted by the 90-km asteroid 335 Roberta in an uncertain path from southern British Columbia & s. Alberta across the cloudy Midwest to Maryland (mostly clear) and Delaware (cloudy). The altitude's fairly high, except in Alberta, but larger telescopes will be needed for this faint star, whose position is uncertain. The path is quite uncertain, it could be as far n. as Edmonton (clear) or New York City (cloudy), or as far south as Cincinnati (cloudy) or Richmond, VA (maybe clear). The star, 2UCAC 28028786, is at J2000 R.A. 14h 24m 08.3s, Dec. -10 deg. 31' 31"; Preston's Web page is at http://www.asteroidoccultation.com/2008_01/0114_335_16534.htm . S. Messner in s. Minn. is on Occult Watcher at -18 km but he will probably be clouded out. 3. From 7:54 pm EST to 6:57 pm CST, an 11.1-mag. star west of eta Geminorum will be occulted by the small (35 km) asteroid 2009 Voloshina in a narrow path crossing from N. Carolina to central Texas (Waco, but could be as far s. as Austin or as far n. as Ft. Worth/Dallas or Norfolk, VA). Astro Meteo shows mostly cloudy skies over Texas and n.w. Louisiana, but clear over the rest of this uncertain path. The star, TYC 1864-00734-1, is at J2000 R.A. 6h 06m 48.7s, Dec. +22 deg. 49' 22"; Preston's Web page is at http://www.asteroidoccultation.com/2008_01/0115_2009_16128.htm . 4. From 9:13 pm EST to 8:14 pm CST, an 11.5-mag. star in a difficult part of southern Monoceros will be occulted by the 75-km asteroid 25 Phocaea in a path over Maryland & DC area (mostly clear), n. W.Va. (cloudy), Iowa (still cloudy), & s.w. S. Dakota (clear). The star, TYC 5394-03285-1, is at J2000 R.A. 7h 10m 10.4s, Dec. -8 deg. 34' 08"; Preston's Web page is at http://www.asteroidoccultation.com/2008_01/0115_25_12389.htm . Nobody has signed up for this event, but I plan to observe it north of the Applied Physics Lab., probably at about +20 to +25 km. I hope to set someone else to observe it from a location south of there, probably near the predicted central line, or just north of there. I may reverse the locations for these two, depending on who is willing to help or host a remote station. I hope that a few other observers in the Washington, DC region can try it as well; I'll try to distribute what I know about the coverage of this event by then around noon Monday. Also, we'll have a better weather forecast then; Astro Meteo says that it will become mostly clear (but with at least some scattered cirrus) in central Maryland, but it is expected to be quite cloudy until a couple of hours before the event. 5. From 6:16 pm PST to 9:23 pm EST (in the DC area, just 10 min. after the Phocaea event just described), a 12.5-mag. star in a sparse part of Aries will be occulted by the 50-km asteroid 398 Admete in a path rather similar to Phocaea's, nominally passing over the southern DC suburbs, but it could be over either Baltimore or Fredericksburg, VA instead. Extrapolated Astro Meteo shows clouds over s. British Columbia, mostly clear over the northern plains, then cloudy from s. Minn. to W. Va, and mostly clear over the DC area & partly cloudy over the Delmarva Peninsula. The star, 2UCAC 39789701, is at J2000 R.A. 2h 48m 22.0s, Dec. +22 deg. 42' 35"; Preston's Web page is at http://www.asteroidoccultation.com/2008_01/0115_398_16539.htm . Observers in s. Minn., at -9 and -38 km, have signed up with Occult Watcher, but they will probably be clouded out. For this faint star, I'll try it from wherever I am for Phocaea; for Admete, this will be about a path-width north of the n. limit. ______________________________________ Some more information about these and other events can be found below, with links to useful Web resources. ____________________________ Asteroidal Occultations in the Mid-Atlantic region 2008 Planet or dur. Ap. Date Day EST Star mag. Asteroid dmag s " Location Jan 12 Sat 0:04 TYC25010817 11.1 Panopaea 2.0 10 6 N.Car.,swVA Jan 13 Sun 21:44 TYC18080641 11.4 Sicilia 4.3 9 7 wNY,wPA,WV,wVA Jan 14 Mon 4:09 TYC50410769 10.4 Winchester 5.5 4 6 NC,sVA Jan 14 Mon 6:09 2UC28028786 13.5 Roberta 1.0 3 13 OH,VA,MD,DE Jan 14 Mon 19:54 TYC18640734 11.1 Voloshina 3.6 4 5 NC,nSC,nGA Jan 14 Mon 21:13 TYC53943285 11.5 Phocaea 1.4 5 7 DE,MD,nVA,Ohio Jan 14 Mon 21:23 2UC39789701 12.5 Admete 1.8 5 10 OH,nWV,nVA,sMD Jan 17 Thu 21:34 TYC13681514 12.0 Fredegundis 0.6 4 8 CT,seNY,PA,sOH Jan 19 Sat 1:49 2UC34790410 13.2 Kolga 0.9 10 12 NJ,ePA,wNY,sON Jan 20 Sun 1:39 SAO 78471 8.7 Jena 5.4 4 2 RI,nCT,wMA,nNY Jan 21 Mon 5:11 2UC31016769 13.3 Aletheia 0.8 9 13 sOH,nKY,WV,VA Jan 21 Mon 21:12 TYC00260627 10.1 Egeria 2.0 9 4 sAZ,nIL,sON,ME Jan 22 Tue 19:37 TYC29781643 10.5 Gifu 5.1 1 5 NY,n&wPA,sOhio Jan 24 Thu 23:39 2UC28731270 11.7 Bathilde 1.7 18 8 ePA,MD,eVA,eNC Jan 27 Sun 20:50 TYC17480099 11.4 Gotho 6.0 2 7 nGA,nSC Jan 28 Mon 21:44 TYC08281463 12.7 Charlotte 1.5 3 12 sNC,nSC,nGA Jan 30 Wed 4:31 2UC36644004 12.7 Mandeville 0.3 8 11 DE,eMD,ePA,NY Jan 31 Thu 23:47 2UC41020481 11.8 Oulu 3.7 5 8 CT,sNY,nPA,sON Feb 5 Tue 18:54 TYC01530660 9.8 Idamiyoshi 6.2 2 4 NJ,n.Penn. Feb 10 Sun 4:44 2UC37355074 11.4 Cohnia 2.9 6 7 NC,swVA,KY The basics of these events for the Mid-Atlantic region, and other upcoming events, are summarized in the table below, from my Mid-Atlantic expeditions page. Accounts of six previous asteroidal occultations are given below: (187) Lamberta on Dec. 20 (219) Thusnelda on Dec. 18 (903) Nealley on Nov. 19 (585) Bilkis on Nov. 11 (15) Eunomia on Nov. 10 (663) Gerlinde on Oct. 29 A 2s occultation of UCAC2 39628815 by 248 Lameia on 2007 Nov 27 was timed visually by Robert Walker near the predicted central line near Hope, Indiana. In addition, on November 16 UT, two asteroidal occultations were observed from at least two stations. First, at about 5:16 UT, the occultation of a 12.7-mag. star by (654) Zelinda was recorded by Kerry Coughlin and Roc Fleishman from opposite sides of the predicted central line in the Ciudad Constitucion area of Baja California sur, and at about 6:33 UT, Aart Olsen and Stuart Levy timed the occultation of 10.2-mag. PPM 92603 by (792) Metcalfia from locations short distances north of the predicted central line near Urbana, Illinois. More about these and other previously-observed occultations is/will be posted on Brad Timerson's N. American asteroidal occ'n results page. BEST EVENT WORLDWIDE PREDICTIONS FOR 2007 AND 2008 Steve Preston has set up Web pages with details of the best asteroidal occultations of 2007 and 2008. Included are events with stars brighter than mag. 10.7 in astronomically populated areas (brighter in less astronomically populated regions) and with at least a 95% chance for an occultation (formal prediction uncertainty) for an observer on the predicted central line. Steve has also created a .csv file (that can be used with Excel and most other spread sheet programs) of over 2000 events during 2008, including all of Edwin Goffin's events and many more of mag. 10.5 and brighter found by Scott Donnell. I have edited down Steve's spread sheet to form this Excel file of what I consider the best 140 asteroidal occultations of 2008. The Excel file includes links to the detailed predictions on Steve Preston's Web site for each event. The list includes all of Steve's A and B priority events, and most of his C events, as well as other occultations of bright stars with reasonably good statistics. Much information about observing occultations of all types is in "Chasing the Shadow: The IOTA Occultation Observer's Manual" available for free here. Much information about asteroidal occultations in general is on Brad Timerson's asteroidal occultation page, with info. about reporting observations, etc. _____________________________________________________ North American observers are encouraged to find updated asteroidal occultation paths near them by consulting the maps and associated tables on Derek Breit's N. American paths Web page. He also has similar maps for Australia here. And now he has these maps for S. America and also Europe. Once a path of interest is identified, you can then get details of the event, including finder charts of different scales to locate the target star on Steve Preston's Web site - scroll down the table to the line with the date and event you want, and click on the item in the right-hand column for the page for the event that links to the regional map, finder charts, and other information. Those outside North America can find some similar information for their areas on the regional asteroidal occultation Web sites listed in (and linked to from) the section, "Links providing possible additional information" in the quarterly asteroidal occultation prediction page of Rob Robinson's main IOTA Web site. You can also just scroll down the list on Steve Preston's Web site which tells the general region of each event, to find events that might be of interest to you. In addition, IOTA members should have a plain text table of events for the year that tells the distances from their location and the circumstances for most predicted asteroidal occultations and appulses computed for their location, the "local circumstances" file with a name like xlcm06.### where "x" is the letter of your IOTA region and ### is your station number in that region. Similar tables can be generated with the WinOccult program that can be obtained from the main IOTA Web site. Also useful is Sander Pool's Web site that lets you input coordinates of your observing location and then it will list all upcoming asteroidal occultations from Steve Preston's site that will occur within a specified distance of your location. This has an advantage over Occult Watcher, described below, in that Sander Pool's site includes all events through the end of 2008 while Occult Watcher only has events in the current detailed update cycle, generally for the next five weeks. Even better than Sander Pool's site is new software called Occult Watcher that I recommend that you install on your computer. With it, you input your position and it searches Steve Preston's predition Web site, informing you of all asteroidal occultations in your region during the next 4-5 weeks, giving probabilities and other details. Whenever a path is updated, the software lets you know. It also has provision for you to specify your observing intentions, and these are displayed along with those of other observers to help plan the overall coverage for the event. Hristo Pavlov in Sydney, Australia wrote this program; you can get it here. He recently updated the program, as explained on his Web site. For all 2007 "Preston" events worldwide, very detailed maps are on Derek Breit's interactive Web page that links to the very detailed maps and satellite imagery of maps.google.com with overlays of the occultation paths and their 1-sigma uncertainty zones. Also on that Web site are station lists giving local circumstances, for many observer stations, now including all of the MPC observatories and other sites in an expanded list of stations. It gives the predicted time of the event, distance from the updated central line, probability that an occultation will occur there, and altitudes of the star and the Sun. If your station is not in that list, please let me and Derek, breit_ideas@hotmail.com , know so that you can be added to future lists. Also on this site are lists of stars, mostly brighter than the target star, that can be used before the event to pre-point stationary (non-tracking) telescopes. Note that the path predictions are not perfect, they can shift due to mainly now to stellar proper motion errors that are increasing with time from the 1991 mean epoch of the Hipparcos satellite observations. So observers not just within the predicted path, but also north and south of it, at least within the 1-sigma uncertainty zones shown by the dashed lines on the maps on Steve Preston's Web site, should also watch for, and preferably be prepared to record and/or time, an occultation. Sometimes (less often, but not impossible) shifts of 2-sigma can and do occur, so observers a little outside the 1-sigma lines are also encouraged to observe. Theoretically, the actual path will be within the 1-sigma lines 67% of the time, and within the 2-sigma lines 95% of the time. ________________________________________________ David Dunham, 2008 Jan. 8, 8 pm EST Phones home 301-474-4722; office 240-228-5609; cell 301-526-5590 office e-mail david.dunham@jhuapl.edu with Blackberry for mobile use home e-mail: dunham@starpower.net .