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All SDA expedition and travel reports online

MeteorsPosted by Koen Miskotte Mon, December 17, 2012 11:49:07

http://www.astrorocker.nl/Meteors/Observations/storys/intro_SDA.htm

Today I finished some work on the SDA expeditions I did within the Dutch Meteor Society in 1984 (Provence), 1985 (Provence), 1986 (Provence), 2001 (Chios island Greek), 2003 (Crete, Greek), 2008 (Roque de Los Muchachos Observatory at la Palma, Spain and 2011 (Namibia). Written reports and lot's of pictures. Enjoy!

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Perseid maximum from the Netherlands

MeteorsPosted by Koen Miskotte Fri, August 17, 2012 10:17:36

Perseid maximum from the Netherlands.
Finally, for the first time in many years we had a clear Perseid maximum in the Netherlands. I had an appointment with Carl Johannink from Gronau to join him to observe the Perseïds. But there was another reason to go there. I would learn to deal with the CAMS software from Peter Jenniskens. Peter is a NASA astronomer working in California (USA) and there he set up a network with low-light video cameras for simultaneous meteor observations.
This software automatically detect meteors and it also calculate orbits from simultaneously recorded meteors. The meteor orbits that this software produces is of a higher accuracy than for example the widely used UFO software.
The reason I got a system of Carl is that the angle of convergence with the CAMS station in Hengelo (Martin Breuker) is often very small. This has a negative effect on the accuracy of the obtained meteor orbits. The angle of convergence is from Ermelo much better so hopefully the accuracy of the meteor orbits will be a lot better.

10/11 august
Friday, August 10th I had to work, but in the afternoon I left Ermelo to travel to Gronau. After the warm reception there Carl showed me the CAMS equipment and software. Boy, this works quite nice and simple. Around 20:30 UT we wanted to start the CAMS observations, but clouds above Gronau prevented us to 21:15 UT to start the CAMS systems. After everything was up and running we quickly drove to Azelo to perform visual observations of the Perseids. Peter van Leuteren would accompany us.
We arrived around 22:00 UT and 7 minutes later I started the observations. After an hour the fatigue came in rapidly and when almost in the middle of my field of view a magnitude 0 Perseid appeared that I did not see (Peter reported this meteor) I decided to stop and take a nap. Saw noises.... A half hour later, Carl woke me up, they also had to stop due to the haze and moonrise. Despite the fatigue, I saw at an average limiting magnitude of 6.25 27 meteors (18 PER, 1 CAP and 8 SPO).

11/12 august
It's been almost noon as Carl wakes me! After lunch, Carl showed me the further processing of the CAMS software. First, all video recordings are measured, and then the calculations of simultaneously recorded meteors were done. Wow, that does it quickly, I remember measuring ​​video meteors with AstroRecord which takes about 15 minutes for each meteor... Now the whole set was measured and calculated within 15 minutes!
After a walk throught Gronau we eat and then a few hours sleep. At 20:00 UT Carl wakes me again. No clouds this time, so both CAMS systems are up and running around 20:30 UT. At the start of one of the CAMS systems Koen sees immediately a meteor whizzing through the field on the screen of the laptop.
Then it's off to the car and go to Lattrop. That was not the public observatory COSMOS at Lattrop because there were 140 people who also wanted to see the Perseïd meteors. Peter has found a great location a few miles north of the observatory. Through a variety of dark roads and a dirt road we arrived there just after 21:00 UT.
WOW, the view is great, no obstruction and it is very dark. When I started the observations (21:23 UT) I immediately see a nice -3 Perseid in Auriga with a persistent train of 8 seconds. And immediately great numbers of meteors were seen. And quite a few bright ones to. After some time more people arrived at our location. Daniel van Os, Remco Scheepmaker, Arjan Ploegmakers and his wife and a number of the observatory staff.

The bright meteors:
21:23 UT: -3 Perseid in Auriga
21:39 UT: -2 ​​Perseid in Pisces / Pegasus
22:00 UT: -2 ​​Perseid
22:13 UT: -2 ​​in Perseid Perseus
22:26 UT: -3 Perseid in Aquarius
23:00 UT: -5 Perseid in Drcao

And of course the necessary stuff of -1, 0 and +1.
The numbers of meteors are also very nice and give the impression of a normal Perseid maximum. Despite moonrise at 23:00 UT, hourly counts continue to rise up to 50/60 Perseïds an hour.
At 01:52 UT, we decide to stop and at 02:35 UT we were back in Gronau.

12/13 august
After another big "morning" rest we look at the CAMS results. The south camera does not have recorded meteors simultaneously with Martin, so there seems te be a problem. The north camera had al lot of meteors. To our surprise it also shows that it has been cloudy for a while in Gronau. Peter also mention that after seeing his pictures from his all sky camera in Borne which also suffered from clouds.

That morning I have subsequently done a measuring session to the video meteors. The afternoon is again used for something different, this time a cycle tour that ends on a terrace. There are some concerns for the next night, there's a lot of cirrus approaching. We see it during the ride, hanging low in the southwest. After dinner the usual nap and then started up the CAMS systems. Then in the car and a half hour drive to Lattrop. Again, we chose the new location because around the observatory there are many trees.
Arriving at the observation field shows that the east is very clear but from the west cirrus is slowly approaching. The first hour we can observe (albeit with clouds rates between 25 and 40%). After 22:25 UT I stopped my observations because there is too much cirrus. Carl and Peter go through. Yet, after a while it seems from the northwest the weather is getting better and also the cirrus solves a bit. I start again at 23:22 UT and from that moment it is quite clear. Well we need to look more to the north because in the east there is still some cirrus present. And it moved extremely slowly away.
We can perceive to 02:00 UT. It is clear that the Perseid activity was less than 24 hours earlier. And that is also hat we expected, because the maximum was reached during the day on 12 August. Also the number of bright meteors (magnitude -2 or brighter) was also lower than previous night. That's a bit strange, usually after the maximum a bit more bright meteors can be seen. At 02:00 we stopped our observations. We were happy because we could observe during two (almost) clear Perseid maximum nights.

During the day, I went back to Ermelo. With me one CAMS system.

Conclusion
A very successful Perseid maximum with both nights mostly clear. Carl and Elisabeth I thank you for the hospitality! And next year we will observe the Perseids from the Provence ...



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Geminids: 30 years of observations (1980-2009)

MeteorsPosted by Koen Miskotte Sun, February 26, 2012 13:44:09

Finally! In the magazine, WGN (Journal of the International Meteor Organization) is our article Geminids, 30 years of observations (1980-2009) was published. I am very proud of this article and have wrote it together with my good friends Carl Johannink, Michel Vandeputte and Peter Bus.
Hopefully, we can write a sequel to this article, with additions from 2010 and more importantly this year (2012) to see if we have the cautious conclusions from the article to confirm or not.
A Dutch language version of this article was previously published in the journal eRadiant 2010-6. This is a free download via the DMS website: www.dmsweb.org

Geminids: 30 years of observations (1980-2009)

Koen Miskotte, Carl Johannink, Michel Vandeputte and Peter Bus

1 Introduction

Among active meteor observers the Geminid meteor stream is known as the most reliable shower that can be observed. The activity period occurs mid December which has both advantages and disadvantages. The fact that winter nights are long and that the stream can be observed all night long is an advantage. During a crystal clear night of 13-14 December, depending upon the perception of the observer, observing conditions and duration, one can count hundreds if not more as thousand meteors. However, the unreliability of the weather especially in Western Europe in December is a disadvantage: In the Netherlands there is less than 10% chance for a clear night while at more favorable locations such as Spain or Portugal this percentage is still only 50%.

The most interesting for the Geminids is that the stream was discovered in the 19th century and gradually became more active. Past decades the Geminid displays became one of the most active annual showers and scientists wonder whether or not this evolution will continue to increase or rather stabilize or decrease. Some researchers concluded that the highest level was achieved around the year 2000, but there are other theories which predict further increasing hourly rates for the next decades. Peter Jenniskens (2006) suggests that the highest hourly rates will occur around 2050 and the ratio of bright Geminids will increase significantly.

In recent years the Geminids peak with a ZHR of ~120-140 meteors an hour. This is more than an usual Perseid return (ZHR of 80). That the activity is actually still increasing or decreasing is a question that requires a good dataset for a long period of time. Just like in climatology conclusions will be possible on basis of many years of intensive observing efforts and this preferably by the same observers.

The Dutch Meteor Society is active since 1979 and in a number of years the Geminids could be very well observed. The evolution of the Geminid activity is rather slow but in a time interval of 30 years some indication of this evolution may have been recorded? In this article we consider an overview of the Geminid activity between 1983 and 2009 and we attempt to verify if any of the proposed models can be supported with our data. With other words, is there anything of this predicted evolution reflected in our data?



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Milky Way and meteors

MeteorsPosted by Koen Miskotte Mon, December 19, 2011 11:25:01

A composition with 3 Capricornids, 3 Southern Delta Aquariids, 1 possible Pisces Austrinid and the Milky Way.

Picture: Milky way and meteors.

Mount: AstroTrac Travel Mount with head EH 3010
Camera: Canon EOS 40D
Lens: Canon EF 15 mm F 2.8 lens.
Filter: None
Accessories: TC 80N3 timer controller,
Location: Hakos Guestfarm, Namibia (16.3 east, 23.3 south)
Software: Corel Paint Shop Photo Pro X12)
Description: , 1000 iso, F 3.2, 90 seconds.

Click on the image for a larger version.

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-6 Capricornid fireball

MeteorsPosted by Koen Miskotte Mon, December 19, 2011 11:15:27

Low at the horizon near the bright star Antares a -6 Capricornid at July 28, 01:50 UT.

Picture: -6 Capricornid.

Mount: AstroTrac Travel Mount with head EH 3010
Camera: Canon EOS 40D
Lens: Sigma 4.5mm F2.8 EX DC Circular Fisheye HSM lens
Filter: None
Accessories: TC 80N3 timer controller,
Location: Hakos Guestfarm, Namibia (16.3 east, 23.3 south)
Software: Corel Paint Shop Photo Pro X12)
Description: One single shot of 57 seconds, F 3.2, 1600 iso

Click on the image for a larger version.

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Fireballs in Namibia

MeteorsPosted by Koen Miskotte Mon, December 19, 2011 11:10:55

Today I made a composition of three all sky picture with 2 Capricornid fireballs and 1 Southern Delta Aquariid.

Picture: Composition of two Capricornids (a -4 CAP near Antares and a -5 CAP in Centaurus) and one -2 Southern Delta Aquariid in Aquarius/Capricornus region.

Mount: AstroTrac Travel Mount with head EH 3010
Camera: Canon EOS 40D
Lens: Sigma 4.5mm F2.8 EX DC Circular Fisheye HSM lens
Filter: None
Accessories: TC 80N3 timer controller,
Location: Hakos Guestfarm, Namibia (16.3 east, 23.3 south)
Software: Corel Paint Shop Photo Pro X12)
Description: One single shot of 57 seconds, F 3.2, 1600 iso

Click on the image for a larger version.

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Two Southern Delta Aquariids

MeteorsPosted by Koen Miskotte Mon, December 19, 2011 09:55:55

Found a picture with two Southern Delta Aquariids (SDA's) from Hakos Guestfarm, Namibia.

Picture: Small and Large Magelhanic Clouds with two SDA's

Mount: AstroTrac Travel Mount with head EH 3010
Camera: Canon EOS 40D
Lens: Canon EF 15 mm F 2.8 lens.
Filter: None
Accessories: TC 80N3 timer controller,
Location: Hakos Guestfarm, Namibia (16.3 east, 23.3 south)
Software: Corel Paint Shop Photo Pro X12)
Description: , 1600 iso, F 3.2, 90 seconds.

Click on the image for a larger version.

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Orionids 2011

MeteorsPosted by Koen Miskotte Thu, October 27, 2011 16:56:24

Orionids 2011

Picture: Composition of 10 Orionids recorded on 22/23 and 23/24 oktober 2011.

After several years with increased Orionid activity (2006, 2007, 2008, 2009 and 2010 the 2011 return was eagerly awaited. Mikiya Sato, a Japanese meteor researcher, had no increased activity predicted and the expectation was that the Orionids would behave "normally". That means many faint meteors and a ZHR of 20-25.Luckily I had during the period of October 19 to 24 a number of clear nights. I observed from the Groevenbeekse Heide, a moor near Ermelo.

In the early morning hours of October 20th the weather cleared already, but because the spells arrived rather late in Ermelo, I had to leave to work. The night of 21/22 October was completely clear. There were some clouds in western direction, but after some time they disappeared in western direction. Occasionally some thin cirrus clouds passed, so the limiting magnitude was a bit low: about 6,3. Despite of that good numbers of meteors were seen. I could observe from 22:10 to 01:45 UT. Longer was not possible because I had to work at 3:00 UT and also the climbing moon was a disturbing factor.
Orionid counts rised up to 10 per period (t.eff. 0.70 hours, 6.0 lm). The Taurids were quite active with hourly counts up to 6. An excellent Orionid with two flares of -2 and 5 seconds train was seen at UT 23:33:45 UT in the constellation of Taurus. Also a number of Orionids of magnitude 0 and +1 were seen, all showing relatively long lasting trains.
I observed during a total of 3,60 hours into the night. I saw 29 ORI, 7 STA, 6 NTA, 5 EGE, 1 LMI and 26 SPO. So it is a total of 73 meteors.

The night 22/23 October was also clear. This night I planned a long meteor session. My Canon EOS 40D went along with the Canon EF 15 mm F 2.8 fish-eye lens. This setup was powered by a Meade accu and a Astronomiser suply unit. Advantage of this is that the camera run all night undisturbed (no need to changing the BP511 batteries). I also used the 12V power for a dew-zapper. Once camera was set, I could concentrate on observing the meteors.
I could observe between 23:00 and 4:12 UT. The air was much cleaner than last night and only occasionally an airplane contrail moved through my field of view. Limiting magnitude up to 6.45. There was a average wind blowing from southeastern direction with a temperature of 2,5 degrees Celcius.
The Orionids were clearly present, the hourly counts rose from 7 to 23 in the last hour (Lm 6.0). The best Orionids were a magnitude -1 and three of magnitude 0. The Taurids were less active than yesterday. In total I saw during 5,13 hours effective observing time 70 ORI, 5 STA, 7 NTA, 5 EGE, 1 LMI and 41 SPO. A total of 129 meteors, which is very good. The camera also scored well with 11 meteors, including the finest a -1 Orionid.

Picture: Orionid of magnitude -2 on 24 oktober 2011 at 01:44:35 UT. Click on this photo to see the persistent train drifting.

The night October 23/24 was also clear. This night a stronger wind was blowing, but temperature was a bit higher than the previous night. I started early in the evening between 18:00 and 19:00 UT. In that period I captured the comet C/2009 P1 Garradd with my Astrotrac Travel Mount, a Canon EOS 40D and EF 200 mm F 2.8 lens. Then, after a few hours sleep at home, I returned to the moor for a few hours meteor observing.
Between 23:53 and 04:16 UT I could observe under good sky conditions. Same camera setup was used as in the previous night. The sky was even a bit better than yesterday with a limiting magnitude of 6.5 in the zenit! The Orionids were much less active with hourly counts of around 13/14. A beautiful Orionid of magnitude -2 was seen at 01:44:35 UT with a few seconds afterglow in the constellation of Eridanus. The meteor was also beautifully captured by the 15 mm fish-eye and on the next five shots is the drifting train still visible.
I saw a during 4,33 hours of effective observing time 45 ORI, 4 STA, 3 NTA, 3 EGE, 2 LMI and 41 SPO. The camera recorded 11 meteors again.

The picture below is a composition of the 10 most beautiful meteors photographed in the nights 22/23 and 23/24 October 2011. The camera made pictures of 29 seconds at 1000 ISO and f 3.2.

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Again: meteor observations

MeteorsPosted by Koen Miskotte Thu, June 02, 2011 14:26:42

Last night (01/02-06-2011) sky was clear in the Netherlands.

T.eff 2,02 hour, 13 meteors (2 of them ANT). Weak meteor activity.

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Meteor observations

MeteorsPosted by Koen Miskotte Mon, May 30, 2011 13:38:09

22/23 and 29/30 may 2011.

22/23 may: t.eff 2.40 hours, 15 meteors (amongs them 1 ANT). Mostly weak meteors.

29/30 may: t.eff 2.50 hours, 16 meteors. A possible +3 tau herculid seen.

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