April 5th, 2007
BREIT IDEAS "Saturn" Video chosen for
inclusion on the NEW JPL "What's Up" feature
This map shows the shadow path
across the United States from the occultation of the
star 32 Lyncis by the asteroid (372) Palma. The
predicted path's limits are in blue, the actual ph
appears in gray.
On the morning January 26th, at least
20 observers spread from Virginia to northern California timed
the occultation of the star 32 Lyncis by the asteroid (372)
Palma — in spite of the track shifting nearly half a path-width
south of what was predicted. Although it was the coldest night
of the season in many areas, it was clear over most of path and
only a few observers were clouded out.
The observations can be fit to an
ellipse with dimensions 207 kilometers by 184 kilometers (129 by
114 miles) to an accuracy of +/-2 km. The actual path was a
little narrower than the predicted path. You can see the
observations projected in the plane of the sky and the fitted
that figure, prepared by Brad Timerson and me, some departures
from an elliptical shape are evident, such as a mountain at the
north end of the asteroid that is left of center. The dashed
line "21" is the last predicted central line of the occultation.
The overall coverage of the predicted path was excellent.
This 1.5MB MPEG file shows the
occultation of the star 32 Lyncis by the asteroid
(372) Palma as seen by Derek Breit in Anderson,
California. Breit created the film from about 300
frames. At his location the star blinked out of view
for 5.2 seconds.
The largest expedition was organized
from the San Francisco Bay area by Derek Breit. Those observers
were joined by Richard Nugent from Houston, Texas, and Mike
Hoskinson from Edmonton, Alberta. They gathered at a motel in
the small town of Anderson in the northern Sacramento Valley
several hours before the occultation and decided how best to
deploy their five stations near exits from Interstate 5. Good
video recordings of the occultation were obtained at each
station. In a similar effort, Paul Maley flew to Salt Lake City,
where he met local observers who set up three stations near
Ogden, Utah. Unfortunately, Maley braved temperatures of 13°F
but saw no occultation. Still his observation was valuable,
being the closest observer to the northern limit to have no
event. His results constrained the shape of the asteroid.
Although about half of the mobile
stations were too far north to see the occultation, the negative
results did show that no satellites of Palma larger than about 4
km could have been on the northern side of the asteroid.
Maps showing the last predicted and
actual paths of the occultation, and more details about the
observations, are at
PLEASE SEE MY PALMA RESULTS
Amateur Observers Are Seeing Double
Summary - (Oct 28, 2005) As Derek Breit headed for
Fremont, California on April 15 to observe a lunar grazing event, little did
he know that he was about to make a discovery that would change the way we
look at standard stars. As he set up his 12" Meade SCT and prepared to
record the event with a low lux videocamera, it seemed like a fairly routine
observation. Until he reviewed his tapes. As frame by frame moved by, he
noticed something a little unusual about upsilon Geminorum - a standard star
against which others are measured, especially in the infrared. In 55 frames
of his video footage, he apparently captured what may be the very first look
at a 11th magnitude companion on a slightly variable star not known to be a
credit: Derek Breit.
of this nature are one of the many reasons why International Occultation
Timing Association (IOTA) members pursue their craft. One of the notable and
historic discoveries on a standard star by occultation means happened in 1819
when Antares' companion star was observed. However, the name of the astronomy
game is confirmation - and also filming and timing the northern limit event
at differing locations were Walt Morgan and Ed Morana.
Contacting IOTA's Dr. David Dunham, Breit forwarded his findings, contacted
team members and started seeking an answer for two unusual seconds of video.
According to Dunham's response, "Almost 2 seconds with a distance of
much more than a km; it's unlikely that the Moon would be that smooth, it
would have to be within about 5m or less for the brightness to remain faint
and constant at that level so long. Especially since this apparently occurred
at nearly every event, a faint, close companion, only 0.01" to
0.02" north of the primary, seems likely."
And Morgan clarifies, "The disappearances and reappearances by upsilon
Geminorum as it passed lunar peaks were usually slow transitions, that is,
the star appeared to fade (or brighten) over a matter of several video
frames. That was not considered unusual because of the fairly large angular
diameter of the star. However, in some instances the magnitude 4.1 star did
not seem to completely disappear on Breit's record: a very faint point of
light remained visible right at the lunar limb."
But confirmation of such importance to the scientific community doesn't stop
there. Breit's findings went out to all IOTA observers and the critical
timing information provided them with the clues they needed. Also recording
the event was Dr. Richard Nolthenius, whose answer was, "Derek's right!
I've just reduced my upsilon Gem graze video recording from last Friday. I
used a PC164c on an 8" f/10 operating at f/6.3, recorded on my Canon
ZR45mc. And the conclusion is.... Derek's camcorder is not going crazy! I
fully confirm his observations and conclusions - this star is a very close
As they continue to work through the geometry and astrometric angles, Dr.
Nolthenius offers the following information from his own recordings:
"The second and 3rd D's look especially like there is an 11th magnitude
companion, and the final D most dramatic of all, with the initial fade
happening in just 3 frames, followed by a definite but very faint 11th
magnitude star left over for fully 1 second before finally
Although it might seem that in a sky filled with innumerable double stars
that a revelation of this type would be of little significance, IOTA member -
Dr. Michael Richmond - knew
better: "I did a little searching to see if there was any other
indication that upsilon Geminorum might be double. The Hipparcos observations
indicate that it is slightly variable, with an amplitude of about 0.08 mag,
but there is no indication of a period. The Astrophysics Data Service has a
number of references which mention upsilon Geminorum. This star has been
chosen to be a calibrator for optical interferometers; that is, people have
decided that it's a good star to use as a reference when doing high angular
resolution measurements. There are two recent papers which list measurements
of its angular size: Borde et al. (A&A 393, 183, 2002), which finds an
angular diameter of 5.00 +/- 0.051 mas, and Richichi and Percheron (A&A
386, 492, 2002), which lists angular diameter of 5.23 +/- 0.31 mas. Given the
Hipparcos parallax of 13.57 mas, this means that the star's diameter is
roughly 0.37 AU. The main star has spectral type listed as late K or early M
giant, with V-band mag 4.08 and K-band mag 0.24. If this is a double star,
with a companion of roughly mag 11, then it would be important to let other
astronomers know: it would no longer be a really good calibration star."
But, Dr. Richmond did not let his findings rest there and he continued to
look for more precise information. Says Richmond,
"I found that both of the catalogue entries were NOT based on direct
measurements of angular size; instead, they were simply estimates, based on
the observed brightness and the shape of the spectrum. In other words, they
were basically fits to a blackbody with a given temperature. I was surprised
to find such indirect evidence appearing in catalogues of angular size, for
use as a calibrator for interferometers."
Recognizing the importance of such a finding as opposed to known data
definitely changes the way we perceive information. Astronomy is a
continually upgrading science as Dr. Nolthenius notes: "For some 9th
magnitude star, finding yet another double is one thing, but for such a
bright star, being a standard for certain measurements should be checked, as
you did. The star is apparently in that fall-through-the-cracks area of
parameter space: a wide enough double to not make for noticeable periodicity
in the radial velocity on a time scale of a few years - the period is likely
in the 100+ year range, (although this is something I will calculate later)
and yet impossibly difficult as a visual binary without using interferometry
or lunar occultations."
Of course, there is far more to this picture than just the discovery of
undisclosed double star. By recording, timing, and observing both grazing and
occultation events, IOTA is able to help determine proper movement, orbit and
lunar limb features as well. As Dr. Nolthenius explains, "The absolute
UT's of the events will help in assessing the slope of the moon at the event
points. However, the most convincing case for duplicity will be identifying
significant periods of time of constant brightness at the very faint
levels." The diffraction of large stars aids astronomers in making more
accurate calculations, "Perhaps there is a secondary that is of order 1
radius or less above the surface of upsilon Geminorum." hypothesizes
Nolthenius, "If such extended periods of very faint levels might be
consistent with limb darkening which is very extended. As a K giant, I would
not expect the limb darkening to be so extreme - normally limb darkening is
more extreme the cooler the star, and late K is not all that cool."
More confirmation was needed and the findings were sent to Dr. Mitsuru Soma of the National Astronomical
Observatory of Japan. Says Soma, "From the comparison of your faint
flash mentioned above and the short duration (0.7s) from R to D of the
primary of Walter Morgan the companion's separation from the primary is
estimated to be about 0.04 arcsec, and this is consistent with the duration
of your gradual R's at 4:39:07 and at 4:40:21 (UT). The spectral type of ups
Gem is K5III which is the same as Aldebaran according to the Hipparcos
catalogue, so I assume that the actual radius of ups Gem is almost the same
as Aldebaran. The angular radius of Aldebaran was estimated to be about 0.010
arcsec from lunar occultations."
But confirmation means being very sure that there is no chance of this being
a diffraction effect. As Dr. Soma explains, "The distance to ups Gem is
3.6 times the distance to Aldebaran (ups Gem's parallax is 0.014 arcsec and
Aldebaran's parallax is 0.050 arcsec) so the angular radius of ups Gem should
be about 0.003 arcsec, which is small so that I think the error arisen from
the assumption that the star is a point source is almost negligible when we
estimate the diffraction effects. Referring to this fact I think 0.04 arcsec
I mentioned above is too large to be attributed to the diffraction
Confirmation continues on a deeper level when Dr. Michael
Richmond plots the photometry of all three tapes of the
Upsilon Geminorum event: "The thing I find very interesting and
encouraging is that I see an asymmetry in these light curves." says
Richmond, "If this is true, then I think we can make a good case that
there may be a faint companion to the primary star. The companion must be
"ahead" of the primary, so that the moving limb of the moon first
blocks (or reveals) the companion, before it blocks (or reveals) the
Dr. Mitusuru Soma also continued with his analysis and presented the papers
at the Journees 2005 meeting in Warsaw on 2005 September 19-21. Based on
available information says, "My conclusion about the position of the
secondary of upsilon Geminorum relative to the primary is 0".04 +/-
0".01 in separation and 70deg +/- 20deg in PA." Although these findings
are preliminary, Soma will continue to review the data and clarify the
results of all accumulative information.
Seeing double? The answer is quite probable. In the mean time IOTA members
will continue to review of the data and further research the duplicity of
upsilon Geminorum. There's a whole big wide sky out there, and each time an
observation of this type is made it adds more to our understanding. While
speckle interferometry is cutting edge of double star detection - the
occultation method can reveal far more. Contributions from dedicated members
are what makes the International Occultation and Timing Association play an
important role in today's astronomy.
Says Breit, "It was a pretty darn good feeling when Dr Nolthenius wrote
"Derek's RIGHT!" When four PhD's say I have found something special
doing a hobby I taught myself from the age of six, that's pretty good.
Something to tell the grandkids... But my real thought was that I finally
have a great video to show others and hopefully get them interested in
observing these very dynamic and temporal events!" So what are the
chances of IOTA members Derek Breit, Walt Morgan, Ed Morana and Michael Richmond making a contribution to the
I'd say double.
Written by Tammy Plotner.
PLEASE SEE MY UPS
GEM DATA >> HERE
As Appeared in the July 2005 Occultation Newsletter
The Surprise Graze of ZC 2131
By Derek C Breit
BREIT IDEAS Observatory
out as any other day of videotaping total lunar occultations. On Sunday July 25th 2004 local time,
I was setup to videotape some events. These would turn out to be the 6th
– 9th events recorded to video with my new Watec 802h videocamera.
I was quite
enthralled with the occultation game to begin with and this new camera was
like the holy grail to me. I had immediately imaged the nucleus of the
Andromeda Galaxy, the Orion Nebula, and other similar objects. There was no
beating this camera!
This was a
Sunday, my usual off day, so I was going to observe whatever was around,
regardless of how spectacular or not the predicted events were going to be.
So I generated predictions with WinOCCULT. There were quite a few, but these
are the ones I successfully observed on video with WWV time signals.
04 07 26 3
58 8 d X 38668 F8 10.4 61+ 103
-7 31 200 53N 69
04 07 26 4
27 59 d 158899 G8 8.4
61+ 103 -12 29 207 53N 69
04 07 26 5
33 47 d 2131 F5 7.7
62+ 104 21 222 6S 190 156 175
04 07 26 5
37 37 d X 38718 F8 10.2 62+ 104 21 223
41S 155 121 141
the weather was quite comfortable. This caused my wife to come see what I was
doing at a very convenient time. The moment was fast approaching for the
total occultation of ZC 2131 at a cusp angle of 6 degrees south. I was very
new to occultations, but I learned quickly about the ruggedness of the
terrain near the South Pole of the Moon.
we are really lucky, this star (on the TV Monitor) will blink off and on
behind a mountain”, I said, employing one of my favorite traits – WISHFUL THINKING.
Seconds later, the star disappeared at 05h 33m 19.5s UT. “Come on back! Come
on back!” I kept repeating. Julie and I were amazed when it did just that at
05h 33m 34.4s with a gradual reappearance. At 05h 33m 46.0s, it disappeared
for good. I plotted the grazeline and learned I was 121 km North of the
Southern Limit. An event like this would have to be, by its nature, pretty
How rare? Just how lucky was I? Let’s see if we
can find out!
Soma wrote on August 1st 2004 –
Derek's deepest point was
-26.301" from the mean lunar limb at
05:42:17.860 UTC… As may be seen
from my reduction shown below, Derek's multiple events are due to a very
steep profile of the Moon.
Height WH Diff
l b Star
" " " o
174.55 +1.782 +1.50 +0.28 -5.88
+2.06 ZC 2131
174.92 +0.278 +0.06 +0.22 -5.88
+2.06 ZC 2131
175.21 -0.866 -0.83 -0.03 -5.88
+2.06 ZC 2131
Height: Observed height from
mean lunar limb
WH: Height in Watts'
Diff: Height - WH
l,b: Libration of the Moon
So, that is
all fantastic, but was does it take to see a representation of the profile
that gives some context to how incredibly lucky I was to observe this event?
I tried a standard graze prediction from OCCULT. No matter what I did, I
could not generate a profile for this event at a Watts Angle of 174.92, the
middle event mentioned by DR Soma above. After some extended conversations
with the Author of WinOCCULT, I can now demonstrate how to display any
let’s return to my results. I record all my observations in the Report
Observations module. At the time, this was the 38th, 39th,
and 40th event of my occultation career. The prior events were all
Total Occultations. There are 43 observations in this file. Here are the ones
that pertain to this graze.
R 2131 1VSRS3 01 1 22221
R 2131 2VSRS3 01 1 22221
on 5mc- Gradual R
R 2131 1VSRS3 01 1 22221
If you use
OCCULT to record your observations, the above will be familiar to you. If you
are new to OCCULT, when you enter your observations, you will end up with
something similar. This is a very useful file!
If you “open the Reductions module,
select the 'Reduce Lunar Occultations' option, and reduce the observations in
this file. In doing this, select 'Normal', and 'apply corrections'. You will
now have displayed a short text list of the reduced observations. On that
form, under 'with displayed observations' select 'Plot against profile -
Graze observations only'.
The results look like this for this surprise
select the menu
option 'Profile information...
Display P,D profile from Historical grazes' and you get the following,
which I have highlighted to point to the three events shown above.
This puts an excellent context to the events
I saw. This is a very useful feature and one I will use frequently, but
possibly in a manner not thought of by others.
I will use this feature not only
to visualize what I have seen, but to VISUALIZE WHAT I MAY SEE!
I will generate a set of total predictions.
I will take any predicted event and note the predicted time and create a
temporary observation file that contains 3 events. First event will be 15s
before predicted, second will be the predicted time, and the third will be
15s after predicted. Using the instructions and examples above, I will learn
what features may effect the observation and I will have a graphic
representation of the direction of the Moon’s motion at the time of the
event. Who knows? Maybe using this great feature of OCCULT, I maybe able to
become even more INCREDIBLY LUCKY!
As appeared in the “Occultation Newsletter” in January 2005
Bay Area “In The Path”
Steve Preston posted a prediction for the occultation of a 10.8-magnitude
star in Orion, about 3° from Betelgeuse, by the asteroid (238) Hypatia, which
had an expected diameter of 148 km. The predicted path passed over the San Francisco Bay
area, and that turned out to be quite accurate, with only a small shift
towards the north, enough to leave Richard Nolthenius, observing visually
from the coast northwest of Santa
Cruz, to have a miss. But farther north, three other
observers video recorded the occultation from their homes, and they were
fortuitously located to define three well-spaced chords across the asteroid
to accurately measure its shape and location relative to the star, as shown
in the figure. The dashed lines show the axes of the fitted ellipse,
produced by Dave Herald's WinOccult program. This demonstrates the good
results that can be obtained by a few dedicated observers with a relatively
faint star; a bright star and/or many observers are not always necessary to
obtain solid useful observations. – David Dunham
The Occultation Newsletter is a publication of
Kiwi Geoff, Tom Webber, and David Breadsell were the 10,000th
visitors to my website.
The prize each of you will
receive is a set of twenty 8 ½” x 11” Lithographs from JPL titled “Our Solar
System”.They are quite nice with
spectacular images on one side, and textual data on the other. I have a set
on my wall behind me. I hope you three enjoy them as much as I do.
I created this website
about 13 months ago to keep myself informed of Occultations in my area and
now it has passed 10,000 visitors in just over a year. Many thanks to the
website owner, without whom this webpage would not be possible, ”Wifey” who
allows me to be me, and to everyone who finds this website useful.
See you at 20,000 when I
have a better hit counter!
Derek Breit – BREIT IDEAS Observatory
If you live in the SF Bay Area (or anywhere else, for
that matter) and wish to know how you can become involved, click the above
link or use the “Contact” link below to email me directly. – Derek Breit