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Taken from Wikipedia (http://en.wikipedia.org/wiki/Occultation)
An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer.
The word is used in astronomy and can also be used in a general (non-astronomical) sense to describe when an object in the foreground occults
(covers up) objects in the background. In the general sense, occultation applies to the visual scene from low-flying aircraft and in Computer-Generated Image
(CGI) technology, where foreground objects obscure distant ones in a dynamic way as the scene changes.
Astronomical events. These include transits and eclipses. The word transit refers to cases where the nearer object appears smaller in apparent size than the
more distant object, such as transit of Mercury or Venus across the Sun's disk. The word eclipse generally refers to those instances in which one object moves
into the shadow of another. Each of these three events is the visible effect of a syzygy.
Every time an occultation occurs, an eclipse also occurs. Consider a so-called "eclipse" of the Sun by the Moon, as seen from Earth.
In this event, the Moon physically moves between Earth and the Sun, thus blocking out a portion or all of the bright disk of the Sun.
Although this phenomenon is usually referred to as an "eclipse", this term is a misnomer, because the Moon is not eclipsing the Sun;
instead the Moon is occulting the Sun. When the Moon occults the Sun, it casts a small shadow on the surface of the Earth,
and therefore the Moon's shadow is partially eclipsing Earth. So a so-called "solar eclipse" actually consists of (i) an occultation of the Sun by the Moon,
as seen from Earth, and (ii) a partial eclipse of Earth by the Moon's shadow.
By contrast, an "eclipse" of the Moon is in fact a true eclipse: the Moon moves into the shadow cast back into space by Earth,
and is said to be eclipsed by Earth's shadow. As seen from the surface of the Moon, Earth passes directly between the Moon and the Sun,
thus blocking or occulting the Sun as seen by a hypothetical lunar observer. Again, every eclipse also entails an occultation.
Please note that the information listed below has been provided by David Dunham and is being automatically pulled from
(http://iota.jhuapl.edu/exped.htm)
Mid-Atlantic Occultations to mid September
- Updated 2008 June 5 EDT
Mid-Atlantic Occultations to mid September - Updated 2008 June 10 EDT
Some Bright Pleiades Stars will reappear on the dark side of an 11%
sunlit Moon low in the sky Mon. morning, June 30
For non-astronomers, "occultation" is a term that astronomers use
for an eclipse of a star by an asteroid or by the Moon.
___________
Asteroidal Occultations
2008 EDT/ Planet or dur. Ap.
Date Day EST Star mag. Asteroid dmag s " Location
Jun 10 Tue 1:29 SAO 208721 7.6 1993 FT19 8.5 0.6 2 MD?,VA,NC
Jun 10 Tue 2:23 SAO 189821 10.5 Volkov 5.9 4 5 ePA,MD,eVA,eNC
Jun 16 Mon 1:26 TYC63092005 10.2 Konko 5.6 1 4 PA,WV;MD&nwVA?
Jun 16 Mon 3:52 SAO 128052 9.1 Svetlanov 7.5 0.7 3 ePA,MD,VA
Jun 16 Mon 23:00 2UC32539092 12.0C Xanthippe 1.4 4 10 KY,sVA,nNC
Jun 17 Tue 23:08 PPM 229688 10.1 Lipperta 5.8 6 4 sWV,sVA,nNC
Jun 18 Wed 2:21 2UC17379703 12.1C Johanna 0.5 11 9 MD?,seVA,NC,SC
Jun 18 Wed 3:17 SAO 186418 8.8 Fortuna 1.9 19 3 Fla,sTex,nMex
Jun 18 Wed 4:54 TYC58360448 10.4 2002 LY38 7.3 0.3 5 OH,PA,MD;VA?
Jun 21 Sat 5:13 SAO 141454 9.4 Robeson 6.3 2 6 KY,sWV,nVA-low
Jun 30 Mon 23:59 TYC08990029 10.3 Aquitania 1.7 7 4 MA,CT,LongIs.
Jul 4 Fri 3:25 2UC22098812 12.4C Hamburga 0.9 6 9 sMD,seVA,NC
Jul 5 Sat 2:04 2UC25789086 12.9C Aida 1.2 8 10 seVA,NC,SC
Jul 9 Wed 5:05 TYC52630124 10.8 Reunerta 3.3 4 6 TN,sNC,nSC
Jul 14 Mon 2:47 2UC33326426 11.6 Volga 3.4 9 8 KY,eTN,wNC,SC
Jul 19 Sat 2:35 2UC23253623 12.8 Pippa 2.4 5 10 MD,VA;PA,NC?
Jul 19 Sat 21:22 SAO 185064 9.5 Danubia 6.8 4 3 seNY,CT,nNJ?
Jul 26 Sat 4:24 SAO 77714 8.2 Sonneberga 8.5 1 2 s.Ont.,s.Que.
Aug 7 Thu 5:22 TYC00370279 11.1 Delila 4.6 4 6 nOH,sPA;nMD?
Aug 10 Sun 4:15 TYC47290479 9.1C Pallas 0.16 18 8 PA,MD,nVA,NJ
Aug 14 Thu 3:59 TYC18171323 12.0 Aurora 1.5 10 8 wNC,VA,MD,ePA
Sep 2 Tue 21:32 TYC06180035 10.5 Williams 4.1 4 7 NJ,nDE,nMD,PA?
Sep 3 Wed 3:41 SAO 97093 6.8 Klemola 9.2 1 2 seMD,sVA;sDE?
Sep 9 Tue 2:18 PPM 143662 10.2 Disa 6.0 2 4 nNJ,ePA,wMD,WV
Sep 11 Thu 3:42 TYC13900745 9.7 Appenzella 8.0 0.5 4 wMD,s&ePA,nNJ
Sep 12 Fri 2:32 SAO 93320 6.0 Metis 3.9 51 1 ON,MI,nAZ,sCA
Sep 13 Sat 3:07 SAO 98173 8.0 Sicilia 8.7 1 2 sWV,cenVA,sMD
*** Dates and times above are EDT, those below are EST ***
Nov 16 Sun 4:22 SAO 96841 9.6 Klotilde 4.3 24 4 MD,DC,VA
We now have "final" astrometric updates for these events except the
TNO ones, and for those after July 6. Stars with designations
starting "2UC" are UCAC2 stars; their magnitudes are not as accurate
as the other catalogs so they might be half a magnitude or more
fainter than the listed magnitude; if near the limit of your
telescope, checking the star's some night before the event is
recommended. Observers should watch these from convenient home or
near-home locations without making a significant mobile effort,
except for some of the better events mentioned below, where the
chances for an occultation warrant an expedition from the DC region,
weather permitting.
If you live within the predicted paths for any of the above events,
or within the 2-sigma uncertainty limits, please try to observe them
from convenient home locations. In addition, you may want to help,
or join, a possible expedition from the DC area that may be
undertaken, weather permitting, for the events on June 17, 18, &
30; July 4; Aug. 7, 10 & 14; Sept. 2, 3, 9, & 12; and Nov. 16. Many
will probably not be attempted due to forecasts of cloudy weather.
I usually give the wider paths with better statistics priority.
June 7, Johanna: Steve Conard was clouded out for this event in
southern Delaware, and the fog was too thick in n.e. North Carolina
for Harry Abramson to observe it. I have heard reports of no other
attempts in the Mid-Atlantic region for this event; that same
morning, I recorded misses from four widely-separated stations in
the Central Valley of California for the occultation of 10 Ceti by
(343) Ostara; so far, we have heard of no positive reports for that
event, whose prediction was apparently compromised by the star's
duplicity, causing a shift of at least 2.0 sigma, according to the
coverage of the total of 14 stations deployed across the predicted
path and much of the uncertainty zone in a carefully planned
attempt.
June 9: This is a low-probability event, the asteroid being (34371)
2000 RC43, 11km across. The star is TYC55170022, spec. type F8.
June 10, (15310) 1993 FT19, only 5 km across. The star is
TYC73620589, spectral type A2.
June 10, Volkov: The star is TYC69260404, also low probability.
June 16, Svetlanov: The star is HIP 114696, spectral type G5.
June 16, Xanthippe: The rather low altitude will make it difficult.
June 17: The star is TYC 61720870.
June 18, Fortuna: The large asteroid & bright star make this the
best eastern USA event of the early summer. The star is TYC
62761878, spectral type A0.
June 21: The star is HIP 82961, spectral type M0. A better-than-
average sky is needed with the Sun alt. -6 deg. and the star only 7
deg. above the western horizon; conditions are better farther west.
July 19, Danubia: The star is HIP 83985, spectral type G5
July 26: The star is HIP 27979, spectral type B9.
Sept. 3: The star is HIP 37135, spectral type B9. The best area is
around Pokomoke City, MD with an altitude of 8 deg. in the east. An
occultation is possible from Salisbury & Ocean City, which are just
n. of the predicted northern limit. The path is also predicted to
pass over Richmond, VA, but the altitude will be only 6 deg. there.
Sept. 9: The star is TYC00081046, spectral type M.
Sept. 11: The star altitude is 9 deg. at Harrisburg, PA, near the
path center. The uncertainty zone is large; an occultation is
possible in central Maryland (Baltimore & the northern DC suburbs) &
northernmost Virginia.
Sept. 12: This is the best asteroidal occultation of the year in
the U.S.A.; observers throughout the country should monitor the star
at least for possible occultations by satellites of Metis. The star
is ZC 462, spectral type B9, and possibly a close double based on a
lunar occultation observation, but that was not confirmed by
HIPPARCOS. IOTA will hold its annual meeting in Apple Valley,
Calif. during the weekend following the event.
Sept. 13: The star is TYC13962190, spectral type G5. The Sun alt.
is -9 deg. at the longitude of DC, which shouldn't pose a problem,
but the twilight will make it more difficult near the Atlantic
coast. The predicted path passes over Charlottesville &
Fredericksburg, VA, and Lexington Park, Salisbury, and Ocean City,
MD. However, The 1-sigma northern limit is north of DC, so an
occultation is possible throughout the DC and northern VA area, as
well as from Roanoke and Richmond, VA. Less likely but possible are
Baltimore and Norfolk.
_______________________________________________
If you live within the predicted paths for any of the above events,
or within the 2-sigma uncertainty limits, please try to observe
them from convenient home locations. In addition, you may want to
help, or join, a possible expedition from the DC area that may be
undertaken, weather permitting, for the events on May 19 & 27; June
7, 18, & 21; Sept. 12; and Nov. 16. Many will probably not be
attempted due to forecasts of cloudy weather. I usually give the
wider paths with better statistics priority.
_______________________________________________
For these asteroidal occultations, see the path maps, detailed
finder charts, and other info. at Steve Preston's Web site.
Very detailed maps for most of these 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 (in the
google maps column). Also on Breit's Web site are station lists
giving local circumstances, for many observer 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. There is also a column that
has a list of stars with declinations similar to that of the target
star, with offset times and declination differences, that can be
used to pre-point a telescope to where the target star will be at
the time of the occultation. There are at least a few bright stars
that can be used to pre-point your telescope during the few hours
before the event so that you don't have to try to find faint target
stars directly. Events not on the above Web sites, generally for the
fainter stars, are on Steve Messner's Web site.
I recommend installing new software called Occult Watcher, where 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.
Much more information about asteroidal occultations in general is
here. Please go to that link to get information for your site and
help us measure the sizes and shapes of these asteroids.
For reporting observations, even if the star is monitored and no
occultation is seen, you should use the new report forms that you
can get here
and click on "Templates for Report Forms". Completed
reports should be sent to reports@asteroidoccultation.com .
Observations during the first 2 months of 2008, including the SAO 99036
grazing occultation and a lunar meteor impact flash recorded during
the recent lunar eclipse, and several asteroidal occultations
observed in the region, are described here.
Brad Timerson has created a comprehensive site about asteroidal
occultations, including links to most other known Web sites
worldwide with useful information (predictions and observations)
about these events, here. He also collects, analyzes, and posts
reports of, observations of these events observed in North America.
_______________________________
Lunar Grazing Occultations to mid Sept. 2008 (and some later)
You can zoom in on some of these paths using Brad Timerson's interactive
Google maps Web site. But you need to know the offsets for the
graze zone in your area; we can help you determine that. Brad can
usually add events not on his Web site by request to him at
btimerson@rochester.rr.com .
DATE Day EDT Star Mag % alt CA Location, Notes
Jun 22 Sun 4:11 SAO 163987 8.1 88- 32 18N DC; Laurel & Baltimore, MD
Jun 29 Sun 5:06 SAO 75591 8.8 19- 32 13N Greensboro, NC; Richmond, VA
Jun 30 Sun 2:42 Taygeta 4.3 11- 10 10N ZC539=19Tau;dbl; Halifax, NS
Jun 30 Sun 3:01 22 Tauri 6.4 11- 13 11N ZC543;5mi.NWof prev.;Pleiades
Jul 5 Sat 21:29 SAO 98729 8.9 11+ 13 9N *Stony Creek, VA;Sun alt. -10
Jul 6 Sun 21:34 SAO 118364 9.0 19+ 18 9N *Greensboro&Varina,NC; Sun-11
Jul 23 Wed 2:16 SAO 128417 7.0 77- 38 12N Lucketts,VA; Oldfld&Tyrone,MD
Jul 29 Tue 4:05 ET Tauri 8.8 13- 15 10N Beaver Ck, MD; Gettysburg, PA
Aug 5 Tue 20:44 21 Vir 5.5 23+ 15 -2S Indiana, York, & Oxford, PA
Aug 9 Sat 23:13 SAO 183872 7.2 61+ 8 6S *Cumberland,MD; Carlisle, PA
Aug 24 Sun 2:48 X05440 8.8 47- 35 9N Richmond, VA; St.Marys C., MD
Aug 24 Sun 3:02 SAO 76500 8.7 47- 35 10N *Cary, NC; Williamsburg, VA
Aug 24 Sun 5:12 BO Tauri 7.8 46- 63 8N s.LexingtonPk,MD; Ashland, VA
Aug 26 Tue 8:07 SAO 78314 8.8 24- 75 7N *Lxngtn,KY;Valncia,PA;Qnsb,NY
Sep 8 Mon 23:33 V3913 Sgr 8.0 64+ 8 14S *Charlotte,NC; Petersburg,VA
Oct 6 Mon 21:35 phi Sgr 3.2 46+ 14 16S Rockland & Brunswick, VA
Oct 22 Wed 6:01 ZC 1331 6.3 40- 56 10S Centreville & Springfield, VA
Some grazes will not be attempted if expeditions are undertaken for
asteroidal occultations within 36 hours of the graze. * in the
Notes column means that no DC-area expedition is planned.
We had many good grazing occultations in the region during early
April, but the weather remained bad most of the time and as can be
seen here, most of them were hosed.. I managed to vidoe record a single D & R
through thickening cirrus during the 136 Tauri graze on April 10 in
s. NJ about 6 miles s.e. of the Delaware Memorial Bridge; the IR
satellite image showed that it was clear just a few miles farther
s.e., towards Millville, NJ.
June 29: The Sun alt. is -9 deg. at Richmond; twilight will make
the event harder to observe east of there.
July 29: The star is SAO 77330, spectral type B8. Beaver Creek is
5 miles s.e. of Hagerstown, MD. The path also passes near
Harrisburg, PA and over Pulpit Rock (Allentown), PA. Farther to the
northwest, itpasses 7 miles from Williamsburg, MA; across southern
NH; and over Orono, ME.
Aug. 5: The star is ZC 1800, spectral type A0. The Sun alt. is -3
deg. at Indiana, PA and -6 deg. at York.
Aug. 24, BO Tauri: The star is SAO 76530, spectral type K3. This
and the X05440 graze provides a chance to observe two grazes in one
night in southern St. Marys County, MD, only about 70 miles s.e. of
DC in the middle of a (likely warm) weekend; if it's clear, I hope
that we can have several observers attempt this pair of grazes. The
path for this graze also passes over s. Delaware and near Cape May,
NJ, where the Sun will be 13 deg. below the horizon (the weak
twilight won't hinder observation).
Sept. 8: The star is SAO 186515, spectral type F3.
_______________________________________________
Total Lunar Occultations
The better total lunar occultations through mid September 2008
visible from throughout the Washington-Baltimore greater metropolitan
area are listed below. Some can be accurately timed by aiming a
camcorder into a low-power eyepiece of your telescope and recording
WWV with the audio.
DATE Day EDT Ph Star Mag % alt CA Sp. Notes
Jun 10 Tue 21:22 D SAO 138313 7.6 54+ 42 80S F9 Sun alt. -9 deg.
Jun 11 Wed 21:30 D ZC 1778 7.0 64+ 40 78N K0 Sun alt. -10 deg.
Jun 15 Sun 1:24 D SAO 182861 7.3 89+ 15 41S F2 Azimuth 224 deg.
Jun 18 Wed 1:43 D 43 Oph 5.3 100+ 22 88N K4 ZC2505; Term. dist. 8"
Jun 19 Thu 2:30 R ZC 2643 6.7 100- 22 79S K1 Terminator distance 7"
Jun 20 Fri 4:20 R ZC 2804 5.8 98- 20 70S K2 Maybe double?
Jun 22 Sun 2:48 R ZC 3055 6.8 88- 30 88S K0
Jun 22 Sun 3:16 R SAO 163965 7.5 88- 30 83N G0
Jun 22 Sun 3:47 R ZC 3057 6.7 88- 32 58N F0
Jun 22 Sun 4:11 G SAO 163987 8.1 88- 33 18N A0 Graze, DC to Baltimore
Jun 23 Mon 2:57 R 44 Cap 5.9 81- 31 27S A9 ZC 3177; close double?
Jun 23 Mon 4:16 R Neptune 7.9 81- 37 56S 6s to reap.; Sun alt. -5
Jun 26 Thu 3:45 R ZC 6 6.9 52- 35 83S G5
Jun 29 Sun 2:42 R SAO 75531 7.7 20- 6 69S G5 Az 68;mg2 11 2",PA 226
Jun 29 Sun 3:54 R SAO 75558 7.7 19- 19 77N A0
Jun 30 Mon 3:06 R SAO 76152 7.2 11- 2 71N B9 Az 60;m2 9 .2", PA 359
Jun 30 Mon 3:10 R Maia=20Tau 3.9 11- 3 66N B8 Close double?; ZC 541
Jun 30 Mon 3:17 R SAO 76167 7.6 11- 4 72S K2 Az 62; Pleiades
Jun 30 Mon 3:17 R SAO 76169 8.1 11- 4 70S A3 R 23s after SAO 76167
Jun 30 Mon 3:23 R ZC 546 7.3 11- 5 80S A0 Probably close double
Jun 30 Mon 3:29 R 24 Tauri 6.3 11- 6 36S A0 ZC 549; Azimuth 64 deg
Jun 30 Mon 3:30 R Alcyone 2.9 11- 6 30S B7 ZC552=etaTau; double?
Jun 30 Mon 3:30 R ZC 548 6.8 11- 6 48N B9 R 29s after Alcyone
Jun 30 Mon 3:31 R SAO 76191 8.2 11- 6 43S A7 R 55s after ZC 548
Jun 30 Mon 3:34 R SAO 76194 7.7 11- 7 32N A0 Azimuth 64 deg.
Jun 30 Mon 3:43 R ZC 553 6.8 11- 8 72S A0 Az 65; spec. binary
Jun 30 Mon 3:58 R SAO 76210 8.2 11- 11 67S A3 Az 67; close double?
Jun 30 Mon 4:04 R ZC 557 7.0 11- 12 68S A1 Az 68; close double?
Jun 30 Mon 4:11 R SAO 76237 8.0 11- 13 29S A0 Azimuth 69 deg.
Jun 30 Mon 4:21 R SAO 76234 7.5 11- 15 66S A0 Azimuth 70 deg.
Jun 30 Mon 4:22 R ZC 562 6.6 11- 15 62S B9 R 42s after SAO 76234
Jun 30 Mon 4:29 R SAO 76249 7.5 11- 16 45S A0
Jun 30 Mon 4:48 R SAO 76259 7.4 11- 20 67S A2 Sun alt. -10
Jul 5 Sat 21:28 D SAO 98734 7.8 11+ 12 69S K5 Sun alt. -9
Jul 7 Mon 22:19 D ZC 1649 6.1 29+ 13 55N K3 Azimuth 260
Jul 9 Wed 22:25 D ZC 1852 6.0 49+ 19 61S A2 Close double?
Jul 10 Thu 21:52 D ZC 1960 6.7 59+ 25 77N K3 Close double?
Jul 13 Sun 23:07 D ZC 2318 6.6 84+ 22 81N A
Jul 14 Mon 0:14 D ZC 2320 7.0 84+ 16 48S B9
Jul 15 Tue 22:21 D ZC 2583 5.8 95+ 21 56N A7 Close double?
Jul 16 Wed 2:35 D ZC 2601 6.8 96+ 11 48N K4 Az 220; Close double?
Jul 16 Wed 23:42 D ZC 2740 6.3 99+ 24 39N G8 Terminator distance 11"
Jul 22 Tue 0:38 R ZC 3380 5.9 85- 25 66S K0 Close double?
Jul 23 Wed 2:23 R SAO 128417 7.0 76- 40 24N G5 Graze, nVA, MD
Jul 23 Wed 3:28 R 25 Piscium 6.3 76- 48 38S A1 ZC 3515; spec. binary
Jul 24 Thu 2:30 R SAO 109354 7.3 66- 38 89S F5
Jul 25 Fri 5:33 R 101 Psc 6.2 54- 63 64S B9 ZC 233; Sun -6; double?
Jul 26 Sat 5:24 R 26 Arietis 6.1 43- 58 87S A9 ZC 370; Sun -8; double?
Jul 29 Tue 2:14 R SAO 77262 7.8 13- 6 76S A3 Azimuth 60
Jul 29 Tue 2:30 R SAO 77272 7.6 13- 9 90N F7 Az 62; close double?
Jul 29 Tue 4:11 R ET Tauri 8.8 13- 16 26N B8 SAO 77330; MD&PA graze
Jul 29 Tue 4:14 R ZC 844 5.8 13- 16 67S B9 Close double, = comp.
Aug 6 Wed 21:48 D SAO 157905 7.8 33+ 9 81S F7 Az 243;mg2 8 4",PA 279
Aug 7 Thu 20:33 D FR Vir 7.1 42+ 23 54N M2 ZC2027;Sun-5;spec.bin.
Aug 9 Sat 21:34 D ZC 2261 6.6 61+ 20 78S K3
Aug 10 Sun 20:14 D ZC 2397 6.5 70+ 23 68N K1 Sun alt. -2 deg.
Aug 17 Sun 21:29 R 67 Aquarii 6.4 98- 12 86N A0 ZC 3334; Az. 109 deg.
Aug 18 Mon 5:56 R ZC 3362 5.9 98- 23 52S K0 Sun-6;mg2 8 ".8, PA323
Aug 23 Sat 5:07 R ZC 470 6.8 57- 69 55S K0 Mag2 10, sep 44",PA 36
Aug 26 Tue 4:21 R SAO 78314 8.8 23- 29 37N F2 PA, NY graze
Sep 8 Mon 20:28 D SAO 186400 7.8 63+ 23 52S G5
Sep 8 Mon 21:11 D SAO 186434 7.5 64+ 21 73S K5
Sep 9 Tue 21:16 D ZC 2781 7.4 73+ 25 45N K4
Sep 11 Thu 0:18 D ZC 2921 6.0 81+ 19 16N K0
Sep 11 Thu 1:20 D ZC 2928 6.4 82+ 11 56N F7 Az 229; close double?
Sep 12 Fri 1:20 D ZC 3057 6.7 89+ 21 55S F0
Sep 12 Fri 20:43 D Neptune 7.8 94+ 26 52N duration 7 seconds
Sep 12 Fri 23:19 D 42 Cap 5.2 94+ 37 74N G2 ZC 3173; spec. binary
On Mon. morning, June 30, the 11% sunlit waning Moon will pass
through the Pleiades, with the reappearance of a few of the bright
stars visible on the dark side, but the Moon will be only a few deg.
above the east-northeastern horizon then. Mark your calendar.
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. Some stars in Flamsteed's catalog are in the
wrong constellation, according to the official IAU constellation
boundaries that were established well after Flamsteed's catalog was
published. In these cases, Flamsteed's constellation is in
parentheses and the actual constellation is given in the notes
following a /.
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 the
main IOTA Web site - see above. Sp. is the star's spectral type
(color), O,B,blue; A,F,white; G,yellow; K,orange; M,N,S,C red. Also
in the notes, information about double stars is often given. "Close
double" with no other information usually means nearly equal
components with a separation less than 0.2". "mg2" or "m2" means
the magnitude of the secondary component, followed by its separation
in arc seconds ("), and sometimes its PA from the primary. If there
is a 3rd component (for a triple star), it might be indicated with
"mg3" or "m3". Double is sometime abbreviated "dbl". Sometimes the
Watts angle (WA) is given; it is aligned with the Moon's rotation
axis and can be used to estimate where a star will reappear relative
to lunar features. The selenographic latitude is WA -270. For
example, WA 305 - 310 is near Mare Crisium.
Many more total occultations will be visible with 5" and larger
telescopes than are listed here. If you want to try to observe some
of these events, it is better to use predictions computed for your
location, such as those given in the IOTA annual predictions that
have been distributed to IOTA members, and are available to others
upon request.
For Pleiades occultations, region of visibility maps and
predictions for hundreds of N. American cities for the brightest 7 stars
are on this page at IOTA's lunar occultation Web site, while
predictions for all of 2008 for stars to mag. 6.0 for 40 of the larger
N. American cities can be downloaded in .zip files from here.
We'll have a good passage the morning of June 30.
________________________________________________________
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.
Information on timing occultations is here. Good luck with your
observations.
Much information about observing occultations of all types is in
"Chasing the Shadow: The IOTA Occultation Observer's Manual"
available for free download at
http://www.poyntsource.com/IOTAmanual/Preview.htm .
_____________________________
David Dunham, 2008 June 10 EDT
Phones home 301-474-4722; office 240-228-5609; cell 301-526-5590
office e-mail david.dunham@kinetx.com with Blackberry for mobile use
home e-mail: dunham@starpower.net .
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