Forum der Vereinigung der Sternfreunde

Comet 45P/Honda-Mrkos-Pajdusakova was imaged on the evening of 2022 May 10 UT. The comet was 19' at PA 257 degrees from the MPC predicted position, close to the JPL predicted ephemeris. The comet showed very well in a green filter and it looked green in the color image. Using the green filter data Astrometrica calculated the magnitude at V=6.7 in an aperture diameter of 5'.

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Cheers, Mike
Arizona

Comet 45P/Honda-Mrkos-Pajdusakova was imaged on the evening of 2022 May 13 UT. The comet was 19' at PA 258 degrees from the MPC predicted position and 3' at PA 258 degrees from the JPL predicted ephemeris position. The comet showed very well in a green filter and it looked green in the color image. Using the green filter data Astrometrica calculated the magnitude at V=6.8 in an aperture diameter of 5'. The comet is still in twilight as can be seen in the color image.

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Cheers, Mike
Arizona

Comet 45P/Honda-Mrkos-Pajdusakova continues to get a little higher in the western twilight skies as can be seen in these images and gif animation collected on the evening of 2022 May 15 UT. The comet is 19' at position angle 258 degrees from the MPC predicted ephemeris position as it moved about 90" to the north of a magnitude 9 star located at RA 04h52m44s and Dec +23*08'20" from 0300-0314 UT in the gif animation. The comet continues to show very well in a green filter and it looked green in the color images. Using the green filter data Astrometrica calculated the magnitude at V=7.2 in an aperture diameter of 5', although the magnitude 9 star was included in the aperture diameter, not sure how Astrometrica calculates the magnitude with a star present in the aperture field. Images taken with no filter showed a coma of about 2' and a tail at least 10' long at a position angle of 84 degrees from the coma. Again Astrometrica calculated the magnitude at V=7.2 in the images taken with no filter. The gif animation shows the comet and stars getting brighter as the sky gets darker after sunset from 0300-0314 UT.

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Cheers, Mike
Arizona

I have provided the MPC with data from 3 different evenings so they can generate some ephemeris that is much better than what they currently have for Comet 45P. First the data was rejected because I did not give them enough, single data is not accepted even though it is hard to get a lot of data together from bright twilight imaging. So I managed to get them more than one data point each evening, then I received this reply after all my efforts.

"Please see https://minorplanetcenter.net/iau/info/ ... html#begin which explains that you should not submit comet astrometry initially. You must first submit astrometry of numbered minor planets in order for us to check your accuracy."

To which I replied.

"I have provided you with data from 3 different evenings showing you where Comet 45P/Honda-Mrkos-Pajdusakova is located in a very bright evening sky using Astrometrica to do the measurements. If you are interested in generating ephemeris from this data you are welcome to do so, if not then others can continue to try to find the comet. I can send you images of the comet if you would like, that would be much more useful than sending you useless asteroid data."

I guess if I had provided them the actual ephemeris generated from the data they would still not accept it. They don't appear to be to interested in where the comet actually is in the evening sky, just how accurate the data may be, even though they don't have anything better at the moment.

I tried, cheers, Mike Olason.

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Cheers, Mike
Arizona

Comet 45P/Honda-Mrkos-Pajdusakova images from the evening of 2022 May 18 UT. Using 12x15 second images taken with a green filter Astrometrica calculated magnitudes of V=7.5, 7.4, 7.6 at 0305, 0310, 0321UT respectively. From the 12x15s image with no filter the measured coma is 2' wide with a tail 30' long at a position angle of 87 degrees from the coma. The color image continues to show a very green comet. The comet is located 13' at position angle 261 degrees from the latest MPC ephemeris update.

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Cheers, Mike
Arizona

Comet 45P/Honda-Mrkos-Pajdusakova from the evening of 2022 May 18 UT. The comet was magnitude 7.6 with a coma 2' wide and a tail 0.5 degrees long at a position angle of 87 degrees from the coma. The comet was located 13' at position angle 261 degrees from the latest MPC ephemeris update. The gif animation shows 8 minutes in the comet's life as it is getting ready to set behind my neighbor's roof at an altitude of 6 degrees. The gif is composed of 8 images each 15 seconds long taken with no filter from 0323-0331UT as the sky was starting to get dark and the light pollution brighter.

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Cheers, Mike
Arizona

Comet 45P/Honda-Mrkos-Pajdusakova from the evening of 2022 May 25 UT. Astrometrica calculated magnitudes of V=8.2 and 8.3 from 12x15 second images taken with a green filter at 0317 and 0323 UT. The color image shows a very green comet. The negative inset image appears to show 2 tails, one 15' long at PA 94 degrees and the other 6' long at PA 271 degrees. The coma is 4' wide. The gif animation shows 16 minutes in the comet's life. The gif is composed of 9 images each 15 seconds long taken with no filter from 0336-0352UT. The ground has finally thawed out in Northeast North Dakota so it is time to go and try to plant the crops on some very wet land, thus these will be the last images of 45P from me until at least July.

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Cheers, Mike
Arizona

Mike, that's really big efforts and great results on a very difficult subject. Congratulations!
I am trying to image the comet remotely as soon as it rises above shed walls. Unfortunately it fades rather quickly ...

Cheers,
Thomas

Hallo,

habe gerade eben den Kometen von Namibia aus fotografiert.
6 x 30 Sekunden mit einem 8" ASA H von Skygems Observatory

Viele Grüße,
Stefan

i think, MIKE should be granted the medal "NEAR HORIZON COMET HUNTER" in SILVER (GOLD is only for comets < 1 degree above horizon)!! i am sure, everybody agrees ......

personally i have no chance, as some hills are 8° high in the 45P direction ......

Roland, to wet to work in the fields today, so I had a good laugh about your silver medal when I read your comments? I have just been lucky enough to be in the right place at the right time with good weather for 45P and C/2021 O3, others who grace this site with their images would have given us much nicer images than mine if they would have had the comets visible above the horizon as I did, including you Roland. The nice thing about the little finder scope that I used to collect the images is that it's shadow against the ST-402ME CCD camera can be used to attain very good polar alignment using the Sun each evening before the Sun set which was very important since I had to constantly find different locations to try and observe the comets around houses, trees and other stuff, without decent polar alignment I would probably have not been able to find these comets before they set in twilight skies. As you know, a lot of the fun in our hobby is all the work-arounds that we do to get our images. I have a bulldozer you could borrow if you wanted to do something about that mountain that is in your way! Cheers, Mike.

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Cheers, Mike
Arizona

dear mike,
if you look on my webcam
http://www.dieholzhaeusler.de/webcam_in ... dsberg.htm
you see the hill on the right side. I think i will buy the area, get rid of the trees and afterwards apply for your bulldozer, thanks in advance, roland

Michael Mattiazzo vermutet in seiner Aufnahme vom 21. Juli einen Zerfall des Kometen: Kein Nukleus und schwächer als 16 mag.



Sam Dean schreibt hierauf, dass der Komet nach dem Perihel schön öfter so aussah und belegt dies mit Aufnahmen aus unserer Fachgruppe:
Micha vom 31.3.2017:
http://www.aerith.net/pictures/jager/45 ... s4x300.jpg
Mike vom 25.5.2017:
http://www.aerith.net/pictures/olason/4 ... olason.jpg

(Ich zähle Mike Olason mal zu unserer Fachgruppe hinzu)

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Uwe Pilz, Fachgruppen Kometen und Astrophysik/Algorithmen.
Oft benutzte Instrumente: Fujinon 16x70 FMT-SX-2, TMB Apo 105/650, Skywatcher Evostar 120/900 ED, Ninja Dobson 320/1440, Smartscope Dwarf-3