SonotaCo.JP

[前田]

Dear Roger,

＞What kind of infrasound detector do you use?

Thank you for information of your infrasound observation.
Sorry, I have not observed infrasound. That is one of a next plan for meteor observations.
I’m busy for HD-, 4K- video observation, now.

Best Regards,
Koji

[geosweiningen]

Dear Koji

Ok, I wish you all every success.

I'm hardly learning the 4K and HD Observation stuff right now.

Best Regards,

Roger

[前田]

Hi All,

I found a large fireball spectrum. I was very very busy in the last month. Then I had forgotten checking captured video clips.
The first order of spectrum was saturated, and the most part of second order was saturated, too. We can see the spectral structure early and last parts of the fireball.
The magnitude of fireball is evaluated -6.6 and the duration is 2.4 sec by UFOAnalyzer.

Regards,
Koji.

[Martin Dubs]

Hello Koji,

you recorded a beautiful spectrum . If you send the uncompressed avi by Dropbox I would try to analyze it. I already have done most of the necessary calibration with an earlier spectrum. My own observations have not been very successful lately, either the meteors were too weak or in the wrong place. You are very lucky.

Regards, Martin

[前田]

Dear Martin,

Thank you for your reply. I try to send the original file which size is 587MB.
This video system, EOS 6D, is different from the former 4K system, SONY a7s. It is a normal HD video.
We will discuss by e-mail in detail.

Regards,
Koji.

[Bill W]

Hi Koji,

That is a very bright spectrum! Good catch!

I've not had many results myself recently. The weather here has been quite poor.

I did however catch a interesting sporadic a few weeks back. Not very detailed but it looked like it had very little iron in the spectrum ( the usual Fe lines looked very "weak") and a very large magnesium signature. What made it really unusual was the orbit.

Several of my friends in the Nemetode group also caught the meteor and Alex ran the images through UFO analyser and UFO orbit. This is the most "cometary" orbit I've seen for a meteor that I've also got a spectrum for.

Cheers,
Bill.

[前田]

Hi Bill,
Thank you for new spectrum. I sometimes saw the spectral type, Na and Mg lines　are strong.　It is a good result for the relation of the orbit. We can dream of a history of meteor body.

By the way, I will not able to go the next IMC, but one of the active Japanese meteor observer, Mr. Fujiwara will go and present a poster with me for meteor spectrum using by HD video. Please discuss with him.

In this morning, I got a small fireball spectrum. This looks Na+Fe type spectra.

Regards,
Koji.

[Bill W]

Hi,

This years IMC is the biggest ever and I noted there is a large contingent of Japanese observers.
I think most are professionals who are then attending the Meteoroids conference after the IMC.
I am really looking forward to meeting them and hearing about your work. Perhaps we will have an IMC in Japan one year!

Best regards,
Bill.

[Martin Dubs]

Hi,

the following picture by Koji Maeda won the 1st prize in the competition for best meteor photo at the IMC 2016. It has been shown in this forum before ( see here: http://sonotaco.jp/forum/viewtopic.php?p=40622#40622) Congratulations!

Meteor spectrum M20151127_222709
The meteor crossed the field of view at the optimum angle and different diffraction orders are visible. The spectrum shows the typical features of a meteor spectrum captured with an objective grating:
- Curved spectra with nonlinear dispersion,
- the higher intensity of the first order to the right of the zero order, typical for a blazed grating
- the second order at far right with the double resolution
The image was captured with a Sony alpha7S with a Canon FD24mm,F1.4 @F2, grating 600 grooves/mm. Software: UFOCaptureHD2 v410, peak image from 4K (3840 x 2160) video recorded at 30 frames/sec.

Martin Dubs[/img]

[SonotaCo]

[前田]

Hi Martin,
I had forgotten to reply this board, sorry.
Thank you for the introduction our prize in the competition for best meteor photo at the IMC 2016.

To all
I applied for this competition by Martin’s recommendation and Martin is co-winner of the prize formally. (He did not write the last report.)

I am very lucky to get the big prize. This image shows one of a current video observation technique. These images will capture easy within the past few years. I hope that analysis of these images help in the development of meteor science.

Koji

[前田]

Hi all,
I have captured a fireball spectrum in this morning. That brightness is unknown, not so large. 0th order was out of field, but the brightness evaluated from 1st order of Na line is -2.4 mag. calibrated from 0th order of stars using by UFOAnalyzer. The velocity was slow, the duration is 5.3 sec. It seems sporadic meteor.
Main part of spectrum is 2nd order， and 1st and 3rd is mixed. The brightest orange line is Na (589 nm). When we observe carefully, the Na line is separated double lines (589.00, 589.59 nm) at 3rd order line　(the right side near the edge)
.
It is rainy season in Japan. I have been lucky.

Cheers,
Koji.

[Bill W]

WOW!,
Now that IS a spectrum!!!

Certainly the best coloured one I've seen. Good Job!

The weather has been bad here too. I've had two clear nights this month so far.

Best Regards,
Bill.

[前田]

Hi all,
I caught a CAP fireball last night. The meteor had two explosions in the path. The max mag. was evaluated -5.5 by the UFOAnalyzer. The spectral shape is a typical CAP, Na line is brighter than Mg line.
I and Japanese some observers feel that bright meteors belonging to the CAP is actively than usual year.

Thank you,
Koji

[Bill W]

Hi,
After watching the sky for about 48 hours I began to think this years Perseids would be a complete washout. (It very nearly was with over 26mm of rain during one night.)
However on the 12th, the skies cleared for just 15 minutes and I managed to catch one decent Perseid spectrum.

The good thing about the monochrome cameras is that they allow the IR part of the spectrum to be captured. This is mostly from the atmosphere but it can say a lot about the energy carried by the meteor.

I was surprised how detailed the molecular components were and I was even more surprised how my spectrum compared with one recorded by chance at the VLT with the very high resolution FORS1 red/near IR spectrograph!

cheers,
Bill.