Interesting, to say the least!
It would be interesting enough if the moon were going to occult the
star, but apparently it's going to be the other way around this time.
I can't believe that Peter didn't comment on this after his post last
week about the ISS pass in front of the tree.
Bob J.
--- Tony Hurtado <Tony-Hurtado@No-Spam> wrote:
> Found this on pastro. Interesting opportunity for those of us that
> plan to be out and about on Sat night @ 9:42 - 9:45pm.
>
> Asteroids with moons, ya say?
>
> -Tony
>
>
> > If the weather holds, there is a great opportunity for Bay Area
> > observers to
> > see the occultation of Asteroid Eugenia's satellite Petit-Prince by
> > a bright
> > star in Taurus this Saturday night about 9:45PM. See below for more
> > details...
> >
> > Hank Sielski
> >
> > ---------- Forwarded message ----------
> > From: David Dunham <dunham@No-Spam>
> > Date: Wed, Mar 5, 2008 at 11:14 AM
> > Subject: [IOTAoccultations] If in the s. USA, you might see a moon
>
> > of an
> > asteroid eclipse a bright star Sat. pm
> > To: IOTAoccultations@No-Spam
> >
> > Those in the possible region of visibility of these events are
> > urged to publicize this event as much as possible, via astronomical
> > society list servers, science writers for public media, etc.
> > ______________________-
> >
> > You could see a relatively bright star, easily seen with
> binoculars,
> > wink out briefly as a moon of the asteroid (45) Eugenia covers it;
> > this rare event will be visible across the southern USA Saturday
> > evening, March 8. You could help determine the location of the moon
> > relative to the asteroid more accurately than can be done directly
> > with the largest telescopes on or near the Earth, if you can obsere
> > this rare event. In 1977, astronomers laughed when Paul Maley and I
> > suggested that asteroids might have small moons based on visual
> > observations of eclipses of stars. In 1994, they stopped laughing
> > when they saw Dactyl, the small moon of the asteroid (243) Ida in
> > images returned from the Galileo spacecraft. Now, many dozens of
> > moons of asteroids have been discovered, but only three times have
> > confirmed eclipse timings been made when these moons covered stars,
> > providing the most accurate information about them (all of those
> > observervations were made in Japan). Saturday evening, March 8, you
> > could join this very small number of people who have seen a star
> > eclipsed by a moon of an asteroid.
> >
> > Eugenia will eclipse the 5.7-mag. star ZC 741 in Mexico and its
> > moons will eclipse it in the southern USA.
> >
> > We could use 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; we have sky charts that
> > should make locating the star rather easy.
> >
> > 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 over central
> > California (over the San Francisco Bay area), southern Nevada,
> > northern Arizona and New Mexico, the Texas panhandle and southern
> > Oklahoma, the Arkansas/Louisiana border area, and southern
> > Mississippi.
> >
> > The occultation by Eugenia's smaller (about 6 km) moon,
> S/2004(45)1,
> > also called Petite-Princesse, will be more difficult to observe,
> > lasting about a third of a second in a narrow path passing over
> > northern Mexico and southern Texas. The location of its path is
> > especially uncertain, it might be almost anywhere between San
> > Antonio and Brownsville, Texas.
> >
> > The star, number 741 in the Zodiacal Catalog and also known as SAO
> > 94227 or HIP 23043 (other catalogs), is in Taurus about 5 degrees
> > above and to the left of of Aldebaran. It can be easily located
> > using all-sky charts and a blowup chart of the Hyades region of
> > Taurus showing Aldebaran, the V-shaped Hyades cluster, and other
> > stars visible with binoculars to find the unique group of 5 stars
> > that includes ZC 741 as its brightest member; these charts are
> > posted on the Web site of the International Occultation Timing
> > Association (IOTA) devoted to occultations of stars by asteroids at
> > http://www.asteroidoccultations.com/observations/NA/ (the box at
> the
> > bottom has the charts, other useful links to path maps, and power
> > point files that describe how to make observations. Also for
> > making observations, with whatever you have available, see
> > http://iota.jhuapl.edu/timng920.htm ; just knowing if an eclipse of
> > the star occurred or not at your location can be important,
> > especially if it did occur. For those interested in the details,
> > the star's coordinates are J2000 RA 4h 57m 22.3s, Dec
> > +17 deg. 09' 13".
> >
> > 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 ZC 741 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@No-Spam <BajaKerry%40gmail.com>, is
> > coordinating observations
> > in Baja California while Pedro Valdez Sada, e-mail
> > pvaldes@No-Spam <pvaldes%40intercable.net>, is coordinating
>
> > them in
> > Nuevo Leon and
> > nearby areas of northeastern Mexico. David Dunham, e-mail
> > dunham@No-Spam <dunham%40starpower.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 Web site at
> > http://www.poyntsource.com/New/index.htm (click on "Spectacular
> > Triple Asteroid Occultation - 45 Eugenia" near the top) also
> > includes static maps showing the paths, with green lines showing
> the
> > predicted central line, blue lines showing the northern and
> southern
> > limits, red lines showing the "1-sigma" error limits, and gray
> lines
> > showing the less likely "2-sigma" error limits. Read the
> > information in the boxes for the interactive maps if you use them;
> > they can be used to view the paths on detailed maps, satellite and
> > in some cases aerial photography, and other map sources to almost
> > any desired level of detail. Derek Breit's 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. Notice that the event will occur at about 12
> > deg. altitude above the horizon along I-35 between Dallas and
> > Oklahoma City, so observers in that area and farther east, where
> the
> > altitude will be even lower, need to take care to find large open
> > fields, the east sides of lakes, or otherwise places with an
> > unobstructed view of the western horizon.
> >
> > 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 and English on the main
> Web
> > site mentioned above. It concentrates on observing the occultation
> > by Eugenia in Mexico but has useful general information for the
> > satellite events in the U.S.A., also.
> >
> > Much information about observing occultations of all types is in
> > "Chasing the Shadow: The IOTA Occultation Observer's Manual"
> > available for free at
> > http://www.poyntsource.com/IOTAmanual/Preview.htm .
> >
> > David Dunham, IOTA, 2008 March 5, 2 pm EST
>
> --
> GSSP Web Page updated 2/25: http://www.goldenstatestarparty.org
> Who's observing where? - http://observers.org/OI-calendar/
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>
--
GSSP Web Page updated 2/25: http://www.goldenstatestarparty.org
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Received on Thu Mar 06 22:58:44 2008