Mid-Atlantic Occultations to Early April 2003
Updated: 2003 March 11This is an update to my March 6th Mid-Atlantic region message mainly to remind you of good occultations in the area this week. Tomorrow evening (Tues., March 11) we have a grazing occultation over the Maryland suburbs of Washington with a reasonable chance for clear skies (Clear Sky Clock says mostly clear, but Accuweather is calling for a sky half-covered with cirrus). Maps and more about the graze are given here. Although convenient for many observers who live near the path and with a reasonably bright star, the small cusp angle will make at least the last half of the graze difficult to observe. The grazing occultation early Wednesday evening is better, with a larger cusp angle, and with the path only a little farther north. I will not be able to observe it myself, but hope others will try it. I will prepare a map and information about it late tomorrow night if the weather forecast gives any reasonable hope for it, but currently Accuweather is predicting broken low clouds at the time. Saturday evening, March 15, we have a good asteroidal occultation (visible with 8-inch and larger telescopes) passing over W. Virginia, western Maryland, and s.central and eastern Penn. (this is a new update issued earlier today, about 0.3 path-width northwest of Steve Preston's previous update), but the current uncertainty is still large enough that the occultation could occur in central Maryland, the northern DC suburbs, and Baltimore, but unlikely in DC, and the eastern and southern suburbs. The path is over 60 miles wide; the predicted southern limit is near Myersville, MD and New Freedom, PA. More will be sent about it later; try to keep your schedule clear to observe the event at least from or near your home. The long-range weather forecast is somewhat optimistic. Updated Mid-Atlantic Occultations and Expeditions to early April 2003 _________________________________________________________________________ Grazing Occultations through early April 2003 DATE Day EST Star Mag % alt CA Location Mar 11 Tue 21:43 ZC 0902 6.6 57+ 51 2N Bethesda, Lanham, & Bowie, MD Mar 12 Wed 19:27 ZC 1049 6.8 66+ 76 5S Germantown and Laurel, MD Mar 12 Wed 23:45 40 Gem * 6.4 68+ 38 5N Scranton,PA & HighBridge,NJ Mar 20 Thu 4:53 82 Vir * 5.0 95- 25 13S Scranton,PA & HighBridge,NJ Mar 22 Sat 2:52 ZC 2217 5.5 80- 30 15S Mt.Airy,Beltsville,&Bowie, MD Apr 3 Thu 19:47 SAO 092910 8.8 4+ 6 6S Laurel & e. Beltsville, MD Apr 6 Sun 18:59 SAO 076729 6.9 21+ 46 1S Cape Henlopen, DE Sun alt.-6d Apr 7 Mon 21:52 SAO 077399 8.4 31+ 25 5N FallsChurch, VA & Waldorf, MD Notes: * - there will be no expedition from the DC area for these grazes. Mar. 11: The path also crosses Tacoma Park and College Park, MD. Mar. 12: 40 Geminorum is ZC 1062, possibly a close double. Mar. 20: 82 Virginis is ZC 1962. Mar. 22: I expect to be out of town, so Wayne Warren will probably lead any DC-area effort to observe this nearby graze. He can be reached by e-mail at w.h.warrenjr@att.net or by phone at 301-474-0814, or possibly by cell phone at 301-518-5754. Apr. 6: The path also goes over Laurel, MD, but it will be more difficult (but not impossible) there with the Sun alt. -4.5 deg. The star may have a relatively faint companion. With other obligations during that time, I will probably skip all the early April grazes, but will pass on information about them by others. _________________________________________________________________________ Asteroidal Occultations through early April, 2003 dur. Ap. Date Day EST Star Mag Asteroid dmag s in. Location Mar 8 Sat 2:30 TYC19100493 11.4 Backlunda 3.2 12 8 n.NC, s.VA Mar 9 Sun 19:33 TYC07860180 11.1 Suevia 2.6 12 7 NJ,eNY Mar 15 Sat 23:01 TYC01622791 11.5 Gerlinde 2.8 13 8 WV,wMD,PA,nNJ Mar 16 Sun 23:07 TYC14160054 10.3 Lomia * 2.5 15 5 s.Ont.,s.Que. Mar 21 Fri 2:11 SAO 98075 8.3 Jupiter 0.5 230m 6 North America Mar 23 Sun 5:02 SAO 96908 6.7 Interamnia 5.0 66 2 Hawaii Mar 29 Sat 6:36 TYC62960177 11.1 Chiron 6.2 14 7 Brit.Col.? Mar 31 Mon 2:46 TYC61500220 10.0 Klytaemnestra3.2 8 5 w.N.C.,n.S.C. Apr 8 Tue 2:56 TYC03290371 11.3 Ino 1.7 11 8 w. N.Carolina Notes: The first two events occurred under clear skies this past weekend (although, for Backlunda, I think it was cloudy in the path east of I-95). I videorecorded the Backlunda occultation from a site southwest of South Hill, Virginia; it was only 3.8 seconds long, showing that I was near the n. limit. That occultation was also recorded from a location in North Carolina and from two in west Texas, with good distribution across the asteroid, giving a good elliptical fit. I set up two stations for last night's Suevia occultation in Delaware, getting successful recordings, but the path for that event was 2 path-widths east of the prediction, going over New Jersey rather than Delmarva, according to a nearly central event recorded at Sherrill, New York. We will not have an expedition from the DC area for the rather good but distant Lomia event on March 16, and it's also doubtful that we'll be trying the March 31st or April 8th events. All events before April 7 now have good astrometric updates. Except for March 23 and 29, the events will be attempted only if the path updates shift the path into the Mid-Atlantic region. In general, only for stars of 9th mag. and brighter will we consider an expedition outside of the Mid-Atlantic states region. Especially for the fainter stars and events of shorter duration, we will plan no observations unless an astrometric update indicates a reasonable chance for an occultation in the Mid- Atlantic states. The asteroidal occultation section of the IOTA Web site at http://www.lunar-occultations.com/iota has finder charts for these events while updated path maps are at http://www.asteroidoccultation.com _________________________________________________________________________ Total Lunar Occultations The better total lunar occultations through early April 2003 visible from throughout the Washington-Baltimore greater metropolitan area are listed below. Many can be accurately timed by aiming a camcorder into a low-power eyepiece of your telescope and recording WWV with the audio. DATE Day EST Ph Star Mag % alt CA Sp. Notes Mar 11 Tue 19:33 D SAO 077736 7.8 57+ 73 46S A2 2nd mag10.3,".4 inPA35d Mar 11 Tue 21:35 D ZC 0902 6.6 58+ 51 5N K0 dark graze, n. of DC Mar 11 Tue 23:57 D ZC 0918 7.0 58+ 26 89S K0 Mar 12 Wed 19:27 D SAO 078824 7.9 67+ 76 58S F0 Mar 12 Wed 23:30 D 40 Gem 6.4 68+ 42 34N B8 Graze in NJ; see above Mar 13 Thu 0:44 D ZC 1068 7.1 68+ 27 56S A2 Mar 13 Thu 0:56 D SAO 078995 7.4 68+ 25 42S A3 Mar 13 Thu 19:45 D SAO 079753 7.8 76+ 72 87S K1 Mar 13 Thu 22:23 D ZC 1194 7.7 77+ 64 76N K0 Mar 14 Fri 1:48 D SAO 079868 7.3 78+ 25 21S K0 Mar 15 Sat 0:02 D ZC 1334 7.0 86+ 54 44N G5 Mar 15 Sat 1:35 D ZC 1342 7.6 86+ 36 21S G5 Mar 15 Sat 18:34 D ZC 1436 6.8 92+ 37 46N K0 Sun alt. -5 deg. Mar 16 Sun 21:13 D ZC 1569 6.9 97+ 52 66S A2 Mar 19 Wed 22:03 R 72 Vir 6.1 95- 21 83N F2 ZC 1937 Mar 20 Thu 3:40 R ZC 1951 7.1 95- 42 74S K0 eq.dbl.,sep.2.8",PA 41d Mar 25 Tue 8:02 D phi Sgr 3.2 45- 22 -67N B8 ZC 2721; Sun alt. +22d Mar 25 Tue 9:18 R ZC 2721 3.2 45- 15 72N B8 close double?; Sun +36d Mar 27 Thu 5:11 R SAO 189469 7.7 26- 12 64S K0 D following the time denotes a disappearance, while R indicates that the event is a reappearance. When a power (x; actually, zoom factor) is given in the Notes, the event can probably be recorded directly with a camcorder of that power with no telescope needed. The times are for Greenbelt, MD, and will be good to within +/-1 min. for other locations in the Washington- Baltimore metropolitan areas unless the cusp angle (CA) is less than 30 deg., in which case, it might be as much as 5 minutes different for other locations across the region. Mag is the star's magnitude. % is the percent of the Moon's visible disk that is sunlit, followed by a + indicating that the Moon is waxing and - showing that it is waning. So 0 is new moon, 50+ is first quarter, 100+ or - is full moon, and 50- is last quarter. The Moon is crescent if % is less than 50 and is gibbous if it is more than 50. Cusp Angle is described more fully at http://www.lunar-occultations.com/iota. Sp. is spectral type-color, O,B,blue; A,F,white; G,yellow; K,orange; M,N,S,C red _________________________________________________________________________ Currently, the IOTA occultation line, 301-474-4945, is working, but I can only update it at home; for weather go/cancel decisions, and other updates and details, look for also for future e-mails, or consult either the main IOTA Web site, http://www.lunar-occultations.com/iota or my Web site, http://iota.jhuapl.edu . Timing equipment and even telescopes can be loaned for most expeditions that we actually undertake; we are always shortest of observers who can fit these events in their schedule, so we hope that you might be able to. Good luck with your observations. David Dunham, e-mail dunham@erols.com, 2003 March 10 Phone home 301-474-4722; office 240-228-5609; car 301-526-5590.