Mastodawn

New #Comet P/2010 LH155 discovered.

Our team observed and reported to MPC potential comet designated 2010 LH155 several times during March and April 2025. IAU MPC reported yesterday 22.4.2025, based also to our (J. Ryske, K. Forssen) observations from observatories Y71 Makroskooppi and M00 Viestikallio, that this object really is a comet. MPC gave it a comet name P/2010 LH155.

https://minorplanetcenter.net/mpec/K25/K25H69.html

Enclosed are two of our discovery images of this new comet, #TychoTracker astrometric measurements and normal inverted stacked image to show this comet's coma and it's short tail. Comet is currently about magnitude 18.2

More details of our observations here https://www.taivaanvahti.fi/observations/show/134345

Jorma Ryske Apr 21

Christian Fröschlin Apr 21

Time lapse of #Sun from last weekend covering 3 hours of real time. 128 x 2000 x 0.9 ms Ha < 0.7 Å in Lunt 40 at f/10.

Jorma Ryske Apr 18

Here the red dwarf #K2-18 photographed last night 17th April 2025 from observatory Y71 Makroskooppi. The Webb telescope has detected possible #biosignature signal of dimethyl sulfide/DMS/DMDS gas in the atmosphere of the super-Earth-sized #exoplanet #K2-18b orbiting it.

The star K2-18 is located under the constellation Leo. In this image, there is a field of view around the star about the size of the moon, the brighter star to the right of K2-18 is HIP 56079 with a brightness of 6.7mag.

Jorma Ryske Apr 17

#Comet C/2025 F2 (SWAN) is still visible nicely. This inverted black&white image was taken at yesterday morning before sunrise 16th April, from my remote observatory Y71 using 0.3m telescope at Spain. C/2025 F2 (SWAN) was low +12° above horizon while Sun was -12° below horizon. Comet's brightness is about 9mag, and very thin dim straight tail is visible over 0.5° toward upper right corner PA 310°, coma diameter is 1.5'. Exposure was 12x30s using clear filter.

Jorma Ryske Apr 8

Here #comet #SWAN25F images taken today early morning 8th April from my remote observatory at Spain. SWAN25F is quite low in the morning sky near Pegasus square upper area between stars Alpheratz and Scheat. It's magnitude is about 9, tail visible almost one degree toward PA 300deg and coma diameter is 5'. Animation 18x30sec in the link below shows also moving tail details.
More info here https://www.taivaanvahti.fi/observations/show/133765

Jorma Ryske Apr 8

Here #comet #SWAN25F images taken today early morning 8th April from my remote observatory at Spain. SWAN25F is quite low in the morning sky near Pegasus square upper area between stars Alpheratz and Scheat. It's magnitude is about 9, tail visible almost one degree toward PA 300deg and coma diameter is 5'. Animation 18x30sec in the link below shows also moving tail details.
More info here https://www.taivaanvahti.fi/observations/show/133765

Jorma Ryske Mar 16

Recurrent nova #TCrB is still collecting material to it's surface, critical level not yet achieved to start eruption. Here a graph during 2025-03-15_0020-0200UT with 40sec time resolution using B filter, taken at Y71 Makroskooppi observatory. Some brightness flickering of it's accretion disk is visible.

Jorma Ryske Feb 24

New #comet C/2025 D1 (Groeller) discovered at 20th Feb 2025. Discoverer is Hannes Gröller with the 2.25m telescope at Kitt Peak. Comet is dim around 20mag and very far away at 14au. The comet's next perihelion is at 19 May 2028 and even then the distance is 14.1au, meaning it will remain dim. Attached is #TychoTracker processed astrometric image taken at 2025-02-23.95UT from observatory Y71 Makroskooppi Fregenal de la Sierra Spain and image showing a very faint coma diameter of 10" and a short faint tail of 15" in the direction of PA 105°, N down E left. https://www.taivaanvahti.fi/observations/show/131966

Jorma Ryske Feb 24

New #comet C/2025 D1 (Groeller) discovered at 20th Feb 2025. Discoverer is Hannes Gröller with the 2.25m telescope at Kitt Peak. Comet is dim around 20mag and very far away at 14au. The comet's next perihelion is at 19 May 2028 and even then the distance is 14.1au, meaning it will remain dim. Attached is #TychoTracker processed astrometric image taken at 2025-02-23.95UT from observatory Y71 Makroskooppi Fregenal de la Sierra Spain and image showing a very faint coma diameter of 10" and a short faint tail of 15" in the direction of PA 105°, N down E left. https://www.taivaanvahti.fi/observations/show/131966

Jorma Ryske Feb 21

Our club's, observatory code #M00 #Viestikallio, biggest telescope is #Lomo AZT-27 0.5m/f:16 Classical Cassegrain, weight 8tn, made in USSR 1984.

During recent months it has been modified to 0.5m/f:3.5/F:1750mm prime focus fast astrograph controlled by NINA software.

Here some first astrophotos using it with old DSLR's Canon EOS 100D/5D/6D from traditional objects like M27 Dumbbell nebula, Stephan's Quintet galaxy group and Monoceros Rosette nebula. More to come...