An AOL Online Chat
Mensa222: Hi! My name is Mike Linnolt, IOTA member. I’m in Honolulu, HI & I try to catch as many
events as I can. I last saw the Regulus occultation on Mar 1st.
EFLASPO: That is a long way from here. I’m in Dallas, TX. And do you just observe for fun, or do you
send in reports to David Dunham or the IOTA people?
Mensa222: So far I just observe & time by visual, but I am working on my CCD video camera system.
I have the PC-23 from supercircuits. It’s a really sensitive CCD video camera, can catch 9 mag with a small telescope.
EFLASPO: Have you taken many pictures with it? Is it suitable to astronomy, too?
Mensa222: I’m just working on setting it up now, hopefully get a few test tapes soon. I just take photos
on color print film. In fact, I have an M42 photo I made from California during the Geminids shower.
EFLASPO: If you get any good images let me know. I could use it on the AAAA web page. We have an occultation
section. Mostly stuff that David Dunham sends me via e-mail. I was going to observe the graze of Aldebaran last
September, but we almost had a hurricane here is Dallas.
Mensa222: Weather can be fickle, anywhere. I did get a neat photo of a pair of Leonids. Do you want to
see it?
EFLASPO: Sure.
Mensa222: I scanned an 8x10, its about 400K Jpeg. You may try to subsample it to less pixels, but then
the meteor trail looses some detail.
EFLASPO: Very nice work. Mike, I am impressed. I really like the colors. Can I post this on the AAAA
web page? I will give you full credit.
Mensa222: Right, as long as its credited. Let me give you some data on it. Film was Kodak PPF, 10-min
exposure, 50-mm f/1.8. Location : Mt. Sobaeksan, Korea. The bright star is Sirius. North is straight up.
EFLASPO: Are you in the Air Force?
Mensa222: No, but I do contract work for the military, sometimes go to Osan AB, Korea.
EFLASPO: Is that base a pretty dark place to be, i.e. away from light pollution? The skies look pretty
dark.
Mensa222: No, I drove about 2 hours to an observatory on Mt.
Sobaek.
EFLASPO: Were there a lot of people there? Must have been a great show!
Mensa222: Wicked cold, though - 10C and 30 mph wind!
EFLASPO: Then you had a good mount. Your image looks pretty steady.
Mensa222: So, it trailed the images slightly due to the wind. I tried to shelter the location as much
as I could, behind the observatory dome.
EFLASPO: Do you do any other astrophotography?
Mensa222: Yeah. I have other photos from the Geminids last December from Southern California. Mostly
I just use telephoto or 50-mm lenses. And I try to go to real dark sky places.
EFLASPO: I recently took a pretty good photo of the Venus/Jupiter conjunction. You can see it on my web
page.
Mensa222: Yeah. I saw that visually here last month, but the timing was not so good for Hawaii.
EFLASPO: Seems you have learned some good tricks for taking
astrophotos.
Mensa222: I have built a simple, portable setup I can take with me on my trips.
EFLASPO: Well, it is getting late here. And I need to work in the morning. I am going to sign off for
now. Good talking to you.
Mensa222: OK. See you later.
EFLASPO: Thanks for the picture. Thanks for a nice chat, too.
Mensa222: Aloha!
EFLASPO: Adios, Amigo!
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1998 Leonid and Geminid Photos
by Mike Linnolt, Honolulu, Hawai
The data on my Leonid photo is as follows :
I observed from the Sobaeksan Astronomy Observatory (SAO), in Sobaeksan National Park, Tanyang,
Korea. SAO is one of 2 optical observatories of the Korea Astronomy Observatory. It is located in a fairly rural
area in East central part of S.Korea, about 200km SE of Seoul. The altitude is approx. 1300 meters. During the
clear sky period, the limiting zenithal magnitude was about 6.5. The Milky way was clearly visible, as well as
the Zodiacal light, arcing up about 40 degrees at a
maximum.
The weather started out very poor. It was mostly cloudy with snow showers, and very cold,
gusty winds. Temperature about -5C. However, after midnight, the sky conditions improved , until after 3:00AM,
it became completely clear.
Even during the partly cloudy period, from midnight until 3:00AM, I saw several bright Leonids
through the broken clouds. After 3:00 AM, I observed continuously, until twilight. I also took 21 photographs,
2 of which showed a total of 3 Leonids. My total exposure time was approx. 150 minutes. I used a 50mm lens at f/1.8,
the exposures ranged from 2 to 10 minutes on 35mm Kodak pro400 (PPF) film. (Normal processing)
I include the best photo, here, as an attachment. It was taken at about 3:30 AM, of Canis Major area (Sirius is
the brightest star in the photo), and shows 2 moderately bright Leonids. Both were colored trails, the fainter
one was green, but the brighter one changed from green to yellow/red ! The photo actually shows the colors much
better than what I saw visually.
Visually, the shower was erratic. After 3:00AM, activity would come in bursts, with periods of maybe 10 secs to
a minute with about a dozen Leonids. Then there would be a lull for several minutes, with few visible at all. From
3:00 to 4:30 AM, activity was low to moderate. The peak of activity seemed to occur from 4:30 AM until 5:15 AM
(19:30-20:15 UT, Nov 17). In that interval, about 130 Leonids were seen. One very bright bolide was seen around
5:00AM, with a trail that lingered several minutes.
I also was on a trip to Los Angeles in time for the Geminids shower, I
drove out to Joshua Tree park, and observed/photographed all night, Dec
13/14.
The sky conditions were excellent, better than Korea & much warmer, with Zenithal limiting magnitude 6.5+ The
maximum activity occured from 08:00 to 10:45 UT. The ZHR approached 300. The average meteor was relatively faint,
3rd magnitude or less, so my photographs did not catch any bright ones. I include an image of the best one, a Geminid
near Orion and the Hyades.
It was a 10 min exposure on 35mm Kodak PJ400 film, 50mm lens f/1.8. I had to brighten it to show the meteor best
in the vignetted edge. Barnard's Loop showed up well, too.
I hope you can find room in your site for my photos. I don't have an astronomy web page, even though I am thinking
of making a section of myham radio page devoted to astrophotos.
Talk to you again, soon. Aloha from Hawai'i.
Mike.
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