Ed's Observed Asteroid Occultations
These pages contain descriptions and videos of asteroid occultation events which I have witnessed myself
Click on the links below for specific event details
In addition to the events below, I've also had missed observations which
sometimes are as valuable as observed occultations since they can bound the
size of the asteroid
372 Palma
2007 Jan 26 UT
The path for the occultation of 32 Lyncis by asteroid 372 Palma was close to 200 miles from home, but going mobile for this event was well worth the long drive. I was part of a team of 6 scattered across the path in northern California, with even more observers watching across the USA. This is one of those events you mark on your calender. The magnitude of the target star was 6.3, the brightest star I've seen occulted by far. The asteroid Palma was also fairly bright at magnitude 10.5. Both star and asteroid were clearly visible. The LiMovie Light Measurement Plot is below. Total occultation time was about 11.5 seconds.
Disappearance 9:47:49.4995 +/- 0.0085 UT
Reappearance: 9:48:00.9775 +/- 0.0085 UT
Equipment used for this event:
Video: Meade 10" LX200GPS with F/3.3 Focal Reducer, WAT902H CCD Video Camera to Canon Elura 100 Camcorder, KIWI OSD Video Time-inserter connected to Garmin-GPS 18
prediction map (North America), prediction summary, star field, site location, video (large - 4.86 MB wmv), video (small - 899 KB wmv), video (60x Time Lapse - 4.75 MB)
697 Galilea
2007 Jan 8 UT
Due to the altitude of the target star, I had to switch from Alt/Az mode to Polar mode so that I could get the Focal Reducer attached. The video is a little "wavy", due to a faulty VCR in my TV/VCR combo (time for a new one). Even with the faulty video, LiMovie was able to track the target star and produce the Light Measurement Plot below. Total occultation time: almost 7 seconds.
Disappearance 4:30:26.037 +/- 0.017 UT
Reappearance: 4:30:33.011 +/- 0.017 UT
Equipment used for this event:
Video: Meade 10" LX200GPS in Polar Mode (with attached superwedge) with F/3.3 Focal Reducer, WAT902H CCD Video Camera to 9" TV/VCR Combo, KIWI OSD Video Time-inserter connected to Garmin-GPS 18
prediction map (North America), prediction summary, star field, video (546 KB wmv)
51 Nemausa
2007 Jan 3 UT
The predicted maximum duration for the Nemausa event was over 2 minutes. The 20.7 second occultation that I witnessed must have put me near the path edge. Even so, this marks the second longest event I've witnessed to date. Cleardarksky was predicting cloudy skies, but remarkably, conditions cleared up nicely before the event.
Disappearance 12:44:28.269 +/- 0.017 UT
Reappearance: 12:44:48.991 +/- 0.017 UT
Equipment used for this event:
Video: Meade 10" LX200GPS with F/3.3 Focal Reducer, WAT902H CCD Video Camera to 9" TV/VCR Combo, KIWI OSD Video Time-inserter connected to Garmin-GPS 18
prediction map (North America), prediction summary, star field, video (1.17 MB wmv)
144 Vibilia
2006 Sep 15 UT
After a few misses, Vibilia was my only successful occultation of 2006. It was unlikely that an occultation would occur from home, so I went mobile northwest of Los Banos, CA. Conditions were extremely windy, so the video jumps around a bit. You can tell where the hot-pixels are in the video, since they aren't moving.
Disappearance 10:27:10.962 +/- 0.017 UT
Reappearance: 10:27:15.733 +/- 0.017 UT
Equipment used for this event:
Video: Meade 10" LX200GPS with F/3.3 Focal Reducer, WAT902H CCD Video Camera to 9" TV/VCR Combo, KIWI OSD Video Time-inserter connected to Garmin-GPS 18
prediction map (North America), prediction summary, star field, video (560 KB wmv)
52 Europa
2005 Dec 3 UT
This was one of the better events for 2005. The star was relatively bright at magnitude 8.9. I went mobile for this one near San Luis Obispo, California. This was my first positive event using the KIWI OSD Video Time-inserter. It worked like a champ. The result was an approximate 4.1 second occultation.
Disappearance 13:07:31.1575 +/- 0.0085 UT Still Image (9KB jpg)
Reappearance: 13:07:35.2115 +/- 0.0085 UT Still Image (10KB jpg)
Equipment used for this event:
Video: Meade 10" LX200GPS with F/3.3 Focal Reducer, WAT902H CCD Video Camera to 9" TV/VCR Combo, KIWI OSD Video Time-inserter connected to Garmin-GPS 18
prediction map (California), prediction map (North America), prediction summary, star field, video (332 KB wmv)
238 Hypatia
2005 Feb 23 UT
For this event my backyard was near the predicted center line, and the path certainty was high, so there was a good change an occultation would occur at my position. What was unexpected was the duration of this event (18.2 seconds) which was more than 2 seconds over the predicted maximum of 16.1 seconds.
Approximate Times: Disappearance 08:42:55.7 UT, Reappearance: 08:43:13.9 UT
Equipment used for this and most of the other events on this page:
Video: Meade 10" LX200GPS with F/3.3 Focal Reducer, WAT902H CCD Video Camera to 9" TV/VCR Combo; Audio: WWV from Ft Collins, Colorado on 5MHz Shortwave Band
prediction map, prediction summary, star field, video (1.1 MB wmv)
1903 Adzhimushkaj
2004 Aug 21 UT
The target star was rather bright at a magnitude at mag. 9.7. My location was about 1/4 path-width outside the predicted path; therefore, the actual path moved southeast, The total event time was about 2.1 seconds which is little more than half the predicted maximum time of 3.8 seconds.
Approximate Times: Disappearance 04:42:22.7 UT, Reappearance: 04:42:24.8 UT
prediction map, prediction summary, star field, video (1.5 MB AVI)
34 Circe
2004 Feb 10 UT
At just over 28 seconds in length, 34 Circe by far surpassed the Eunike event for the longest event that I have witnessed. Although, the star was rather dim at a magnitude of 11.6, the combined light of star and asteroid made it easy to see the occultation. I was able to make out both star and asteroid in the field of view.
prediction map, prediction summary, star field, video (1.0 MB Windows Media, .wmv)
185 Eunike
2003 Nov 16 UT
185 Eunike surpassed the Arsinoe for the longest event that I have witnessed (almost 15 seconds) at the time. At a magnitude of 9.7, it is also the brightest star that I have seen occulted. I was able to make out both star and asteroid in the field of view.
prediction map,
prediction summary,
star field,
small video (1.4 MB Mpeg-1),
large video (2.8 MB Mpeg-1)
125 Liberatrix
2003 Aug 27 UT
125 Liberatrix was another event I didn't expect to see, since the prediction was well to the south. As a matter of fact, if the event had been on a weekend, instead of midweek, I probably would have traveled south to increase my chances, and might have missed it altogether. I was pleasantly surprised when the duration of the event actually exceed the predicted maximum by a full second. This means that either Liberatrix is bigger than previously thought, or more likely, it happened to be rotated so that it's long side was in the direction of movement. This event was the first with my F/3.3 Focal Reducer. The focal reducer increases the limiting magnitude of the system, as well as provides a larger field of view.
prediction map, prediction summary, star field, video (1.7 MB Mpeg-1)
404 Arsinoe
2003 Feb 21 UT
At the time, 404 Arsinoe was the longest event that I had witnessed (around 9 seconds). It was also the first time I was able to make out both star and asteroid in the field of view. I remember it was very humid that night, and had to keep a towel over the dew shield for extra protection.
prediction map,
prediction summary,
star field,
video (4.3 MB
Mpeg-1)
859 Bouzareah
2002 Sep 20 UT
I knew after 1024 Hale, I needed more power. I went out and purchased a Meade 10"LX200GPS SCT. Oh yes, the GOTO capability doesn't hurt either for these kinds of observations. 859 Bouzareah was my first success with the SCT.
prediction map, prediction summary, star field, video (3.1 MB Mpeg-1)
1024 Hale
2002 Feb 26 UT
You never forget your first time. For me it was 1024 Hale. Using my 6" Orion Eq. Reflector, and newly purchased Watec 902H CCD video camera, I was barely able to make out the 10.8 magnitude target star. The prediction was well to the north, so I had little hope that that night would be my first time. Then it happened. It only lasted 2 seconds, but when the target star disappeared like magic, I was sure beyond doubt. There was no fading in and out, and even though the seeing conditions were poor that night, I knew I caught my first event.
prediction map, prediction summary, star field, video (4.7 MB Mpeg-2)
Note: Since the target star was so dim, I had to use an Mpeg2 format
to preserve as much quality as possible. Even so, the target star is
still very difficult to see. It may be necessary to bump up the monitor
brightness. Also my Watec CCD has a few hot pixels, the one that is
most prevalent is in the upper left corner. It's been mistaken for
a star on more than one occasion.
For information about the value of timing asteroid occultations visit the International Occultation Timing Association web-site. Many thanks to Steve Preston's Asteroid Occultation Predictions. Light Measurement Analysis via LiMovie Software.
