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Skywarden,
Ursa Astronomical Association
Kopernikuksentie 1
00130 Helsinki
taivaanvahti(at)ursa.fi

Ursa Astronomical Association

4 observations and 0 comments in queue.

Only observations that have a description and at least one image attached.

Binocular comet Leonard

5.12.2021 at 05.47 - 05.55 - Orimattila, Artjärvi, Viestikallio (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C / 2021 A1 (Leonard) is relatively close to Earth at 0.42 AU and moves very fast relative to the stars. The attached 15x30s = 7.5min exposed L / Clear filter images show only a portion (less than 1 °) of the comet's long tail, which consists of several rapidly changing fan-shaped structures. Coma diameter 12 '. Figure 1) 15x30s L / Clear filter, stacked according to the comet's optocenter. Start 2021-12-05_0347 UTC. Figure 2) Animation 15 frame 30s, the comet's fast motion is shown during ~ 8 minute exposures. Start 2021-12-05_0347 UTC.

Images: 2 pcs

Nova M31N 2008-12a

14.11.2021 at 18.46 - 20.45 - Orimattila, Artjärvi, Viestikallio (I)
Jorma Ryske, Etelä-Suomen kosmol. seura

The recurring nova M31N 2008-12a, which erupts in the M31 galaxy about every year, once again brightened into a detectable 18.5mag target this morning on November 14, 2021. Picture 1) Stacked picture of 30x90s exposures on November 14, 2021 at 19:00 between the light of the moon and even thin clouds. Figure 2) Animation of the situation on November 8, 2021 and November 14, 2021 Photometric measurements: #NAME DATE MAG MERR FILT M31N2008-12a 2459533.20185 18.531 0.0714 L M31N2008-12a 2459533.21329 18.534 0.0769 L M31N2008-12a 2459533.23041 18.419 0.0741 L M31N2008-12a 2459533.24182 18.528 0.069...

Images: 2 pcs

Binocular comet Churyumov-Gerasimenko

11.11.2021 at 01.30 - 04.30 - Orimattila, Artjärvi, Viestikallio (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

I tried to make the comet 67P / Churyumov-Gerasimenko dust dust / dust trail more clearly visible with a longer exposure time of 30 minutes than with a 5-minute exposure taken two days earlier https://www.taivaanvahti.fi/observations/show/102096 . The dust trail was now dimmer. The transparency of the atmosphere may not have been as good as the 8.11.2021 observation or the dust trail is but dimmer because there are two more days on the perihelist. However, the dust / dust trail stands out in front of the comet's core, continuing beyond the image. The first negative image has normal exposur...

Images: 2 pcs

Telescopic comet Churyumov-Gerasimenko

9.11.2021 at 01.23 - 05.00 - Orimattila, Artjärvi, Viestikallio (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

The comet 67P / Churyumov-Gerasimenko shows both the normal tail and the interesting dust trail in front of the comet in the negative images below. The dust trail has comet particles about 0.1 mm to 1 cm in size left by the comet in previous rounds. If the Earth went through this dustbin, it would show great stellar flights, but the Earth's orbit and the 67P / CG's orbits would not meet, unfortunately or fortunately. Figure 1) 5x60s Clear filter from 2021-11-09_02: 33UT Figure 2) Stacked 4 pcs 5x60s Clear filter from 2021-11-08_23: 33 UT, taken every hour. Stars reduced by image proces...

Images: 5 pcs • Comments: 3 pcs

Telescopic comet Schwassmann-Wachmann 1

9.11.2021 at 01.00 - 02.30 - Orimattila, Artjärvi, Viestikallio (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

The 29P / SW 1 comet has had a superburst throughout the fall. Here's a comet pictured with LRGB filters 4x10x120s. At the heart of the comet stand out interesting showers.

Telescopic comet Churyumov-Gerasimenko

17.10.2021 at 00.05 - 06.00 - Orimattila, Artjärvi, Viestikallio (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

67P / Churyumov-Gerasimenko presents his handsome almost 20 'long tail here, even though he is only a mag10 comet. 67P / CG is relatively close at a distance of 0.44au from Earth so Koma’s morphology is also starting to show. Figure 2 shows a 50 minute exposure with a narrow band cyan radical gas CN 3883Å filter treated with CometCIEF. It distinguishes two jets both in the direction of the normal tail PA 290 ° and also in the curved forward outgoing jet in the direction PA 110 °. Picture 1) 20x60s, L / Clear filter, 2021-10-17 02: 30UT, FoV 28'x18 ' Figure 2) 10x300s, narrowband 38...

Images: 4 pcs • Comments: 2 pcs

Nova M81 PNV J09554017+6902478

3.10.2021 at 05.20 - 05.35 - Orimattila, Artjärvi, Viestikallio (I)
Jorma Ryske, Etelä-Suomen kosmol. seura

A possible nova has been observed in the M81 galaxy, according to the announcement received yesterday, October 2, 2021, around mag20 various very dim. At the end of a gusty night, I exposed the light from the M81 through a 16 * 1min Baader Clear filter to see if it could be seen. The boundary magnitude in a single 60s exposed image is about 19.0, so moving the limits of the vehicle’s performance is moving. In addition, the M81 effectively obscures Nova, which may be quite close to its core, with its light, so a negative observation of this is recorded even if something ashy at the assumed poin...

Images: 2 pcs

Telescopic comet Schwassmann-Wachmann 1

3.10.2021 at 01.56 - 05.12 - Orimattila, Artjärvi, Viestikallio (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

In the comet 29P / Schwassmann-Wachmann 1 there is a superburst going mag17 => mag11. It looks a bit like the recent comet 17P / Holmes eruption but in mini size due to the 29P / SW 1 distance. The discharge contains at least CO gas which appears bluish. The figure below also shows one jet 45 "in length PA 270 °. The actual Coma is 60" in diameter and surrounded by a faint teal gas coma 150 "in diameter. Photometrically measured, the brightness of the comet's core is m2 12.85R σ: 0.08896 Aperture radius 6". Picture 1) RGB bin2 3x15x120s, FoV 36'x29 ' Picture 2) RGB bin2 3x15x120s, ...

Images: 5 pcs

Telescopic comet PANSTARRS

14.9.2021 at 22.00 - 00.20 - Orimattila, Artjärvi, Viestikallio (II)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2017 K2 (PanSTARRS) is quite far away 5.4au from both Earth and Sun. However, comet's nucleus is big, several tens of kilometers and that's why it's quite bright already, m1 around mag 12.5. Image 1) 15x60s bin2, Baader Clear filter, star stacked, no flatsImage 2) 15x60s bin2, Baader Clear filter, comet optocenter stacked, no flatsImage 3) 12*300s bin2, Semrock 387nm/15nm filter, tracking and stacked to comet optocenter, no flatsImage 4) 3x15x60s bin2, Astrodon RGB, comet optocenter stacked, no flats Image1 and image2 showing comet through L/Clear filter. 5' tail to PA 11° is visible. ...

Images: 4 pcs • Comments: 3 pcs

Telescopic comet ZTF

8.9.2021 at 23.38 - 00.20 - Orimattila, Artjärvi, Viestikallio (I)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2021 E3 (ZTF) is another dim mag 16.5 comet so quite challenging to observe also because it's in star rich area in Milky Way in constellation Hercules. Good "second light" object for new remote controlled observatory. Coma 15", tail 25" towards PA 90°. Image 1) 20x2min exposure, tracking comet, stacked to comet optocenter, LPS filter, FoV 12'x10', north up, east left

Telescopic comet Palomar

8.9.2021 at 22.40 - 23.25 - Orimattila, Artjärvi, Viestikallio (II)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C / 2019 O3 (Palomar) is a dim mag 16.0 comet currently quite far away at 8.7au distance from earth and 8.9au from sun. It's high in the sky in Constellation Draco so I choose it as a "first light" object of our club new remote controlled Viestikallio Observatory in Artjärvi. Image 1) 20x2min exposure, stacked to stars, LPS filter, FoV 25'x20 'north up, east left Image 2) 20x2min exposure, stacked to comet optocenter, LPS filter, FoV 12'x10 ', north up, east left When moving my Telescope from Helsinki light polluted skies to Artjärvi dark skies a week ago, I Forgot LP...

Images: 2 pcs

Telescopic comet NEOWISE

18.3.2021 at 21.31 - 23.45 - Helsinki, Maunula (I)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2021 A2 (NEOWISE) is now much dimmer than I last observed it at February 16th. In this 115min exposure using 387nm narrowband filter cyanogen CN 3883Å radical gas coma diameter is 0,6'/40.000km and wide fan-shaped cyanogen gas tail length 1'/60.000km towards PA 330° is visible. Comet current distance from sun is 1,62au and from earth 1,43au. I took also R channel photometric image and although the image had poor S/N I measured comet R channel brightness as 16,3mag. CN channel brightness measurement is difficult because lack of 3883Å reference stars, not very scientific but when using B...

Telescopic comet NEOWISE

16.2.2021 at 22.15 - 23.55 - Helsinki, Maunula (II)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2021 A2 (NEOWISE) cyanogen CN radical gas coma diameter 1,7'/50000km and wide fan-shaped cyanogen gas tail length 3,4'/100000km towards PA 10° is visible in this 3870Å narrowband filter image. Comet distance from sun is 1,46au so the sun heat and UV radiation is strong enough to sublimate comet icy surface and photodissociate gases like CN at 3883Å.    Image 1) 30x180s=90min with CN 387nm narrowband filter at 2021-02-16 20:15-21:50UT Image 2) Processed cropped image 1 with CometCIEF to enhance coma and tail morphology. No significant details visible.

Images: 2 pcs

Telescopic comet ATLAS

9.12.2020 at 21.44 - 03.14 - Helsinki, Maunula (II)
Jorma Ryske, Etelä-Suomen kosmol. seura

C/2020 M3 (ATLAS) is moving farther away from earth but is still relatively near at distance 0,45AU. I tried to observe comets rotating CN gas jet which was visible earlier 20.11.2020. Seems that the CN jet is still visible but clear rotation is no more observable. Figure 1) CN 387nm filter 18*5min exposure starting at 2020-12-09 22:47UT, showing large 15' (equivalent to 300 000 km) cyanogen coma around oval shaped optocenter. FoV 36' x 29'. Figure 2) G filter 20x20s image at 2020-12-09 19:56UT showing tail 4'. FoV 36' x 29'. Figure 3) R filter 20x20s image at 2020-12-09 19:44UT showing dust t...

Images: 4 pcs

Telescopic comet ATLAS

20.11.2020 at 22.50 - 05.13 - Helsinki, Maunula (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2020 M3 (ATLAS) is quite near earth 0,36au and it's Sun distance is 1,33au. It is emitting cyanogen CN gas with rate Q(CN)=1.62+ E25 s-1 (14.11.2020 http://www.astronomerstelegram.org/?read=14174). It is about the same rate as 46P/Wirtanen had two years ago (18.12.2018 Q(CN)= 1.17E+25 s-1) of which rotating CN jet was then clearly observed. Image 1) Animation of 4 frames, each stacked 60 minute exposure through CN/387nm narrowband filter and CometCIEF processed. Some amount of CN jet rotation is visible during ~4 hours of frames mid-exposures. Image 2) CN filter exposure 12x300s=60 min...

Images: 3 pcs

Faint naked-eye comet NEOWISE

10.7.2020 at 01.00 - 02.00 - Helsinki, Haltiala (IV)
Jorma Ryske, Etelä-Suomen kosmol. seura

C / 2020 F3 (Neowise) had to be spotted even though it was hiding in the very bright northern sky in early July. The fields of Haltiala in northern Helsinki have a good view to the north almost to the horizon, so in the morning to test whether there is a comet. At first, Capella was also hidden behind the illuminating night clouds, but when it was found, the directions were roughly known and a comet was found with 10x42 binoculars in a moment. As the shadows of the illuminating night clouds shifted so that the comet remained between them in a suitably cloudless place "placemarked", it quite ea...

Images: 3 pcs • Comments: 1 pcs

Telescopic comet ATLAS

10.4.2020 at 22.07 - 23.00 - Helsinki, Maunula (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2019 Y4 (ATLAS) is disintegrated and preceding fragment is visible in this R-channel image. Fragment is 10" from comet's main optocenter towards PA 285°. Main image is 25x120s frame stack and two other 12x120s image stacks 30 minutes between.   Image 1) R filter 25x120s 2020-04-10 19:07UTImage 2) R filter 12x120s 2020-04-10 19:07UTImage 3) R filter 12x120s 2020-04-10 19:35UT   Image 4) Added strongly stretched version of Image 1. Three fragments can be seen, second fragment preceding first most behind fragment of 7" PA260° and third fragment preceding first most behind of 12" PA290°  

Images: 4 pcs

Telescopic comet ATLAS

9.4.2020 at 22.10 - 23.27 - Helsinki, Maunula (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2019 Y4 (ATLAS) optocenter is strongly oval shaped in all colour channels RGB and UV/CN and there is not point like optocenter visible representing comet's possible disintegration. Moon phase was 95% but fortunately it was low in the sky. Image 1) Crop of Astrodon R filter (image 3) showing strongly oval shaped optocenter. One fragment can be seen preceding/leading very close optocenter, measured 9" towards PA 290° / "2:30 o'clock"Image 2) Astrodon G filter showing 7' diameter coma and 11' tail towards PA 95°, exposure time 10 minutes. Image 3) Astrodon R filter showing 3' diameter com...

Images: 6 pcs

Binocular comet ATLAS

4.4.2020 at 22.03 - 23.42 - Helsinki, Maunula (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2019 Y4 (ATLAS) was strongly interfered by moon (85%) so coma and tail measurement are not comparable to my earlier observations under "darker" Helsinki normal light polluted sky.   Image 1) Astrodon G filter showing 7' diameter coma and 6' tail towards PA 105°, exposure time 10 minutes. Image 2) Astrodon R filter showing 2' diameter coma and 5' dust tail towards PA 105°, exposure time 11 minutes. Image 3) Astrodon B filter showing 3' diameter coma and 5' tail towards PA 105°, exposure time 10 minutes. Image 4) CN 387nm narrowband filter showing cyanogen 3883Å gas coma about 11' diamet...

Images: 5 pcs

Binocular comet ATLAS

30.3.2020 at 22.28 - 01.07 - Helsinki, Maunula (III)
Jorma Ryske, Etelä-Suomen kosmol. seura

Comet C/2019 Y4 (ATLAS) is now 1,05au from earth and 1,50au from sun and brightening all the time.   Image 1) Astrodon G filter showing 8' diameter coma and 5' tail towards PA 120°, exposure time 10 minutes. Image 2) Astrodon R filter showing 2' diameter coma and 4' dust tail towards PA 120°, exposure time 15 minutes. Image 3) Astrodon B filter showing 4' diameter coma and 8' tail towards PA 120°, exposure time 10 minutes. Image 4) Semrock CN 387nm narrowband filter showing cyanogen 3883Å gas coma about 18' diameter and dim tail towards PA 120°. Exposure time 60 minutes. Cyanogen gas coma visi...

Images: 5 pcs • Comments: 2 pcs

Search result contains observations from time period 1.1.2000 klo 00.00 - 6.12.2021 klo 6.51.