Clear for this evening's Occultation by (304) Olga in Virginia
Help is needed from observers especially in Virginia to cover the path
The path also passes over southern West Virginia and eastern Kentucky
New: 2006 April 24
Clear skies are forecast for Virginia for the occultation of a 10th-mag. star in southeastern Gemini, about 8 deg. north of Procyon, by the 68-km asteroid 304 Olga at 9:17 pm EDT Monday evening, April 24. The path also crosses southern West Virginia and eastern Kentucky. We need your help to observe this event to measure the size & shape of the asteroid. We want to try to coordinate coverage of this event with the help of the station list, from which you can determine your local circumstances, below. _____________________________________________________________________ We need help from as many of you as possible in Virginia, West Virginia, and Kentucky to observe Monday evening's Olga occultation. The occultation will occur at 9:17 pm EDT for observers in all of these States. The actual path could be north of the predicted one, so observers in the southern suburbs of Washington, DC are encouraged to try to observe for a possible occultation in their area; similarly, the path could shift south so that observers in southern Virginia, in the Norfolk/Tidewater area, are also encouraged to monitor the star. Olga is a lower-numbered asteroid with a better history of astrometric observations than Bronislawa, so I think the prediction for Olga's occultation will be better than that for Bronislawa. The Astro Meteo (Clear Sky Clock) forecast now shows clear sky with reasonably good transparency across central and eastern Virginia, but cloudier over southern West Virginia and Kentucky. The target star, 10.4-mag. TYC 0777-00134-1 (full designation) at R.A. 7h 37m 22.7s, Dec. +14 deg. 33' 21", is 8 deg. north of Procyon in Gemini near the Canis Major border. The target star is 1.5 deg. southeast of 6th-mag. 68 Geminorum and about 15' north and a little west of a 7th-mag. star that should be visible with most finder scopes. Detailed finder charts of different scales, as well as path maps and other information, are on Steve Preston's Web site as path maps and other information, are on Steve Preston's Web site. A central occultation is expected to last 3 seconds with a very noticeable 5-mag. drop. I've put Steve Preston's finder charts this Word file. I find it easier to print full charts from that; when I try to print directly from the Web views, the charts are truncated a lot. The time of closest approach, & circumstances of the occultation are given in the station list at the end of this message, item 3. Conditions are good for the Mid-Atlantic region, with the target star more than 45 deg. above the eastern horizon in a dark sky shortly before the end of astronomical twilight. The target star, 11.0-mag. TYC 6121-00106-1 (full designation) at R.A. 13h 35m 02.8s, Dec. -15 deg. 18' 05", is 5 deg. southeast of Detailed finder charts of different scales, as well A central occultation is expected to last 5 seconds with a very noticeable 3-mag. drop. If your station is not in the list below, it may be in the longer list on Derek Breit's Web site. If your station is not in that list (edit it and search for your name and/or location), please let me and Derek, breit_ideas@hotmail.com , know so that you can be added to future lists. To display the list properly, it must be viewed with a fixed-space font such as Courrier ("select all" and click on "fonts" to change to Courrier if your message arrives with a non-fixed-space font) and use a small-enough font size to prevent line wrapping. The second column, "Prob.", gives the percent probability for the occultation happening at the location given. The occultation should occur within 0.3 minute of the predicted time given in the "U.T." column; note that April 25, 1h UT = local date/time April 24, 9 pm EDT. The star will be at least 45 deg. above the eastern horizon for all locations in the list below. Even for observers in Virginia, there will be only about half an hour of dark-enough sky to try to find the target star, and observers farther west will have less time, and also probably more clouds to contend with. The Sun's altitude at the time of the occulation is in the last column of the table. So far, I've received three responses, from observers at distances of +11, -65, and -69 km for this evening's Olga occultation. Please try to observe this event if you can. The Astro Meteo (Clear Sky Clock) forecast now shows clear sky with mediocre transparency across central and eastern Virginia, and only slightly cloudier over southern West Virginia and Kentucky. It does show one patch of clouds southeast of Fredericksburg, VA, but I don't think the predictions are good enough to reliably predict features that small. We'll see what develops in the visual satellite images late this afternoon. _____________________________________________________________________ After the distance from predicted central line (first) column, I mark an "h" for observers whom I hope will try to observe this occultation, and * marks Klosterman's line at -65 km. V marks the probably video or CCD observations that will probably (neither certain) be attemped at +11 and -69 km. I will now be able to leave Bowie, MD at 7 pm and will drive as far south as I can from there, possibly even getting as far south as the predicted central line near Ashland, VA. In any case, I'll avoid Oldham's possible chord either to the north or south (hopefully to the south). Joe Sedlak hopes to go mobile, but if so, he'll probably only be able to reach the northern limit, or a little south of it. This will be my last mass mailing before the event; I will make a last update between 5:15 and 5:30 pm that I can only post here. After that, I will no longer be reachable by e-mail, only by cell phone at 301-526-5590. Hope you might be able to try this occultation; let me know if you can to help plan our most effective coverage. From now until 5:30 pm, e-mail will reach me fastest if you send it to my office at david.dunham@jhuapl.edu rather than to this address. Steve Preston's 03/17/2006 update Occultation of TYC 0777-00134-1 by 1315 Olga on 2006 Apr 25 UT Distance from center of occultation path - in km Prob.Location Longitude Latitude U.T. Sun km % o ' o ' h m o 165 0 ** Northern limit plus 3-sigma, event very unlikely ** 164 0 Columbia MD Peter Chen - 76 50.1 39 13.1 1 17.6 -16 162 0 Barnesvl MD John Menke - 77 22.8 39 13.2 1 17.5 -15 162 0 Athens OH George Eberts - 82 5.4 39 20.4 1 17.3 -12 160 0 Columbia, MD Don Gardner - 76 50.4 39 10.8 1 17.6 -16 152 0 Laurel MD David Skillman - 76 50.6 39 6.9 1 17.6 -16 151 0 Gaithersburg, MD Jim Vail - 77 12.1 39 6.9 1 17.6 -15 151 0 SEVERNA PARK MD LEONARD~BOBBY - 76 36.4 39 5.4 1 17.6 -16 148 0 Silver Spring, MD Ed Abel - 77 0.8 39 4.9 1 17.6 -16 144 1 Savage VA NOVAC via Stewart - 77 51.7 39 4.7 1 17.5 -15 144 1 STEPHENS CITY VA BROOKS~JOHN - 78 11.7 39 5.2 1 17.5 -15 142 1 Bethesda, MD Vince Sempronio - 77 7.1 39 1.6 1 17.6 -16 142 1 GORF16IN Be Wayne H. Warren Jr. - 76 49.6 39 1.3 1 17.6 -16 142 1 Sterling VA Patrick Lowry - 77 24.7 39 2.6 1 17.5 -15 142 1 STERLING VA ROBERT STEWART - 77 22.9 39 2.3 1 17.5 -15 141 1 Sterling VA Peter Gural - 77 22.7 39 1.7 1 17.5 -15 141 1 CINCINNA OH BASIL H. ROWE - 84 22.1 39 9.8 1 17.1 -10 140 1 Greenblt MD GAC Northway Field - 76 52.0 39 0.4 1 17.6 -16 140 1 Bethesda MD Mikael Reardon - 77 5.8 39 0.7 1 17.6 -16 140 1 BOWIE MD ANDREW W. SEACORD I - 76 46.4 38 60.0 1 17.6 -16 140 1 ColegPrk MD UMD Ob.,E. Warner - 76 57.4 39 0.1 1 17.6 -16 139 1 BETHESDA MD JAY H. MILLER - 77 7.6 39 0.2 1 17.6 -16 139 1 GlennDal MD Joe Sedlak - 76 47.8 38 59.2 1 17.6 -16 139 1 Parsells VA NOVAC via Stewart - 77 32.0 39 1.0 1 17.5 -15 138 1 GREENBELT MD DUNHAM~DAVID W.- 76 52.2 38 59.2 1 17.6 -16 138 1 Annapols MD M.Shea & J.Huddle - 76 30.0 38 58.2 1 17.6 -16 138 1 CINCINNATI OH VENTRE~JOHN E. - 84 25.3 39 8.3 1 17.1 -10 138 1 Bowie MD Glenn Bock - 76 44.9 38 58.8 1 17.6 -16 137 1 TAKOMA P MD HAROLD WILLIAMS - 77 0.0 38 58.8 1 17.6 -16 136 1 Bethesda MD John Wetmore - 77 6.5 38 58.7 1 17.6 -16 134 1 Lanham MD ai Sol. J. Carrico - 76 50.0 38 56.9 1 17.6 -16 134 1 Cincinnati OH Gene Herrmann - 84 18.0 39 06.3 1 17.2 -11 133h 1 Woodmore MD Chuck Quintero - 76 47.9 38 56.4 1 17.6 -16 130 1 Bowie MD John Wood - 76 43.9 38 54.3 1 17.6 -16 130 1 WASHNGTN DC MASON~BRIAN U.S.N.O - 77 4.1 38 55.3 1 17.6 -16 129 1 Vienna VA 2003_428J. Guerber - 77 16.4 38 55.1 1 17.6 -16 128 2 FALLS CHURCH VA FIALA~ALAN - 77 11.7 38 54.2 1 17.6 -16 122 2 ** Northern limit plus 2-sigma, some chance for an event ** 122 2 Haymarkt VA Hopewell Obs. - 77 41.9 38 52.2 1 17.5 -15 122 2 Arlngton VA Scott Fearing - 77 5.4 38 51.0 1 17.6 -16 117 3 TEMPL HL MD RICHARD J. TAIBI - 76 54.2 38 47.6 1 17.6 -16 117 3 McKendre MD R. Taibi meteor - 76 38.2 38 46.9 1 17.6 -16 115 3 ALEXANDRIA VA BOLSTER~ROBERT - 77 6.4 38 47.2 1 17.6 -16 109 5 Nicklasn VA NOVAC via Stewart - 77 21.0 38 44.0 1 17.6 -16 103 6 Nokesvil VA Sam Somers - 77 34.5 38 41.7 1 17.5 -15 101 7 Warrenton, MO Doug Kniffen, - 91 13.3 38 43.5 1 16.7 -6 99 7 WOODBRIDGE VA BROWN~BRIAN W. - 77 15.9 38 38.7 1 17.6 -16 94 9 Crockett VA NOVAC via Stewart - 77 43.0 38 37.0 1 17.5 -15 90 10 Hughesvl MD MICHAEL CAPOBIANCO - 76 49.2 38 32.8 1 17.6 -16 86 12 ChrlotHl MD Jeff Hunt - 76 45.6 38 30.6 1 17.6 -16 83 14 ST. LOUIS MO CLARK~WAYNE E. - 90 20.4 38 35.1 1 16.8 -6 82 14 BigMedos VA NOVAC via Stewart - 78 28.0 38 32.0 1 17.5 -15 81 15 Ocean City MD - 75 4.8 38 23.4 1 17.7 -17 79 16 ** Northern limit plus 1-sigma, occultation very possible ** 77 17 Nanjemoy MD S. MD. Astro. Soc. - 77 8.0 38 26.2 1 17.6 -16 75 18 Salisbury MD - 75 36.0 38 21.6 1 17.7 -17 69h 22 Greenbank WV Bob Anderson - 79 49.4 38 26.5 1 17.4 -14 63 26 FRDRKSBG VA David Wilson - 77 27.6 38 19.2 1 17.6 -16 59 28 Huntngtn WV Jeff Ball - 82 25.8 38 24.6 1 17.3 -12 57 30 Goshen KY Charles Allen III - 85 34.2 38 24.6 1 17.1 -10 44 40 Verona VA Karaffa & Wine - 79 1.0 38 12.0 1 17.5 -15 41 42 Louisville KY Newman~Harry - 85 36.5 38 15.7 1 17.1 -10 37 45 Point Lookout, M mobile site - 76 19.4 38 2.5 1 17.6 -17 36 46 *** Northern limit *** 34 47 BowlngGn VA mobile site Dunham - 77 21.2 38 3.6 1 17.6 -16 32 48 Ladysmth VA mobile site Dunham - 77 31.0 38 2.9 1 17.6 -16 27 52 CharlottesvilleV Univ.ofVA McCo - 78 31.4 38 2.0 1 17.5 -15 24 53 Chincotg VA planning only - 75 20.5 37 53.3 1 17.7 -17 20 56 Carmel Church VA I95 mobile - 77 28.0 37 56.0 1 17.6 -16 19 56 Lexingtn KY via Charles Allen - 84 29.4 38 3.6 1 17.2 -11 11V 59 Oliver VA Robert Oldham - 77 31.3 37 51.1 1 17.6 -16 10 59 Fan Mtn Obs VA Univ.ofVA 32in - 78 41.5 37 52.7 1 17.5 -15 1 60 Ashland VA I-95 exit, mobile - 77 28.0 37 45.6 1 17.6 -16 0 60 **** Centre Line **** -5 60 Hanover C.H. VA Shell gas D. D - 77 23.1 37 42.4 1 17.6 -16 -8 60 w.Atlee VA I95 & SlidingH - 77 27.5 37 41.0 1 17.6 -16 -12 58 RICHMOND VA DONALD A. MCAFEE - 77 38.4 37 38.9 1 17.6 -16 -14 58 Carnels Store VA e.I295 & Meado - 77 22.5 37 37.7 1 17.6 -16 -16 57 Mchncsvl VA Ken Wilson - 77 22.2 37 36.6 1 17.6 -16 -16 57 Mechanicsville V e.I295 & US360 - 77 21.5 37 36.6 1 17.6 -16 -17 57 SimpkinsCorner V e.I295 & Creig - 77 19.0 37 35.5 1 17.6 -16 -18h 56 Richmond VA Randy Tatum vid. - 77 33.0 37 35.7 1 17.6 -16 -21 55 Cold Harbor VA Ed's Nursery D - 77 15.8 37 33.3 1 17.6 -16 -27 52 Richmond Airpt V w.I295 - 77 18.0 37 30.2 1 17.6 -16 -35 47 Varina Grove VA w.I295 & VA5 - 77 20.2 37 26.2 1 17.6 -16 -36 46 *** Southern limit *** -39h 43 Fincastl VA John Goss RVAS - 79 58.2 37 28.4 1 17.4 -14 -51 35 Wiliamsb VA William&Mary Col. - 76 43.0 37 16.1 1 17.6 -17 -65* 24 Yorktown VA Michael Klosterman - 76 27.0 37 7.6 1 17.6 -17 -69 21 Langley VA Hampton 16in pe - 76 22.6 37 5.2 1 17.6 -17 -69V 22 Roanoke VA Michael Good RVAS - 80 4.7 37 12.7 1 17.4 -14 -79 16 ** Southern limit plus 1-sigma, occultation very possible ** -87 12 PADUCAH KY NICKOLAS~MICHAE- 88 35.8 37 5.3 1 16.9 -8 -90 10 Suffolk VA Tidewater CC Ob via - 76 26.2 36 54.3 1 17.6 -17 -96h 8 CHESAPEK VI DENNIS A. ROWLEY - 76 23.6 36 50.9 1 17.7 -17 -100 7 BowlGren KY Hackney,Wright,etc. - 86 27.0 36 59.4 1 17.1 -10 -122 2 ** Southern limit plus 2-sigma, some chance for an event ** -143 1 Gatesvil NC Norfolk A.S.Obs.sit - 76 47.6 36 26.7 1 17.6 -17 -154 0 w. N. Carolina Mike Bruce - 80 16.5 36 26.8 1 17.4 -15 -155 0 Clarksville TN H. Sherbourne - 87 21.8 36 29.7 1 17.0 -9 -162 0 Greenbrr TN R.Melng.c/oDegenhar - 86 48.0 36 25.8 1 17.0 -10 -165 0 ** Southern limit plus 3-sigma, event very unlikely ** _____________________________________________________________________ David Dunham, 2006 April 24, 3:30 pm phones home 301-474-4722; office 240-228-5609; cell 301-526-5590 Home (IOTA) e-mail dunham@starpower.net