Ronald Bijtenhoorn
@astronald.bsky.social
🏠 Heemskerk (NL) | 🔭 Amateurastronoom
🌍 Website: www.bijtenhoorn.nl
RUIMTESOEP -Observaties vanuit mijn Achtertuin
🌍 Website: www.bijtenhoorn.nl
RUIMTESOEP -Observaties vanuit mijn Achtertuin
🔭 The Sun in H-alpha - First light with my new Lunt telescope! I captured an image between the passing clouds, just before the Sun disappeared behind our house.
There’s still plenty of room for improvement but I’m quite happy with this first photo nonetheless. 😀
#Astrophotography #lunt #halpha #sun
There’s still plenty of room for improvement but I’m quite happy with this first photo nonetheless. 😀
#Astrophotography #lunt #halpha #sun
November 9, 2025 at 3:21 PM
🔭 The Sun in H-alpha - First light with my new Lunt telescope! I captured an image between the passing clouds, just before the Sun disappeared behind our house.
There’s still plenty of room for improvement but I’m quite happy with this first photo nonetheless. 😀
#Astrophotography #lunt #halpha #sun
There’s still plenty of room for improvement but I’m quite happy with this first photo nonetheless. 😀
#Astrophotography #lunt #halpha #sun
🔭 Earlier this evening, before the Moon rose, I spent about an hour tracking Comet C/2025 R2 (SWAN). Its brightness has now dropped to magnitude 8.4 and after rounding the Sun, the comet is heading back toward the distant regions beyond the Kuiper Belt.
#Astrophotography #seestar #c2025r2 #comet
#Astrophotography #seestar #c2025r2 #comet
November 7, 2025 at 9:19 PM
🔭 Earlier this evening, before the Moon rose, I spent about an hour tracking Comet C/2025 R2 (SWAN). Its brightness has now dropped to magnitude 8.4 and after rounding the Sun, the comet is heading back toward the distant regions beyond the Kuiper Belt.
#Astrophotography #seestar #c2025r2 #comet
#Astrophotography #seestar #c2025r2 #comet
🔭 Last night the clouds suddenly cleared, so I quickly set up the Seestar outside. I was able to capture the Iris Nebula for about 2 hours (until it started raining again at 10:15 p.m.) 😀
* Distance: 1,300 lj
* Const: Cepheus
* Mag: 6.8
#Astrophotography #seestar #NGC7023 @kat-astro-bot.bsky.social
* Distance: 1,300 lj
* Const: Cepheus
* Mag: 6.8
#Astrophotography #seestar #NGC7023 @kat-astro-bot.bsky.social
November 2, 2025 at 1:12 PM
🔭 Last night the clouds suddenly cleared, so I quickly set up the Seestar outside. I was able to capture the Iris Nebula for about 2 hours (until it started raining again at 10:15 p.m.) 😀
* Distance: 1,300 lj
* Const: Cepheus
* Mag: 6.8
#Astrophotography #seestar #NGC7023 @kat-astro-bot.bsky.social
* Distance: 1,300 lj
* Const: Cepheus
* Mag: 6.8
#Astrophotography #seestar #NGC7023 @kat-astro-bot.bsky.social
🔭 Over the past few days, I’ve tried several times to capture comet C/2025 A6 (Lemmon) again.
Last night, I finally managed to do it! The conditions weren’t great and I couldn’t see it with the naked eye, but luckily I could spot it through my binoculars.
#Astrophotography #seestar #c2025a6 #comet
Last night, I finally managed to do it! The conditions weren’t great and I couldn’t see it with the naked eye, but luckily I could spot it through my binoculars.
#Astrophotography #seestar #c2025a6 #comet
October 29, 2025 at 12:42 PM
🔭 Over the past few days, I’ve tried several times to capture comet C/2025 A6 (Lemmon) again.
Last night, I finally managed to do it! The conditions weren’t great and I couldn’t see it with the naked eye, but luckily I could spot it through my binoculars.
#Astrophotography #seestar #c2025a6 #comet
Last night, I finally managed to do it! The conditions weren’t great and I couldn’t see it with the naked eye, but luckily I could spot it through my binoculars.
#Astrophotography #seestar #c2025a6 #comet
🔭 Last night I set up the Seestar to capture M15 — a globular star cluster in Pegasus.
Over 12 billion years old and among the oldest objects in our galaxy, M15 has an exceptionally dense core that may contain a massive black hole. 😀
#Astrophotography #seestar #M15 @kat-astro-bot.bsky.social
Over 12 billion years old and among the oldest objects in our galaxy, M15 has an exceptionally dense core that may contain a massive black hole. 😀
#Astrophotography #seestar #M15 @kat-astro-bot.bsky.social
October 14, 2025 at 6:10 PM
🔭 Last night I set up the Seestar to capture M15 — a globular star cluster in Pegasus.
Over 12 billion years old and among the oldest objects in our galaxy, M15 has an exceptionally dense core that may contain a massive black hole. 😀
#Astrophotography #seestar #M15 @kat-astro-bot.bsky.social
Over 12 billion years old and among the oldest objects in our galaxy, M15 has an exceptionally dense core that may contain a massive black hole. 😀
#Astrophotography #seestar #M15 @kat-astro-bot.bsky.social
🔭 This morning I set my alarm for 4:00 AM to try to capture comet C/2025 A6 (Lemmon). After waking up, I looked outside and saw Jupiter in the sky, so no clouds! 😀
But the conditions weren’t ideal though, so hopefully, I’ll get another chance soon.
#Astrophotography #seestar #c2025a6 #comet
But the conditions weren’t ideal though, so hopefully, I’ll get another chance soon.
#Astrophotography #seestar #c2025a6 #comet
September 28, 2025 at 1:53 PM
🔭 This morning I set my alarm for 4:00 AM to try to capture comet C/2025 A6 (Lemmon). After waking up, I looked outside and saw Jupiter in the sky, so no clouds! 😀
But the conditions weren’t ideal though, so hopefully, I’ll get another chance soon.
#Astrophotography #seestar #c2025a6 #comet
But the conditions weren’t ideal though, so hopefully, I’ll get another chance soon.
#Astrophotography #seestar #c2025a6 #comet
NGC 6946 (The Fireworks Galaxy) is a bright spiral galaxy in the constellation Cepheus.
NGC 6946 was nicknamed the Fireworks Galaxy because it has hosted 10 supernovae over the last century, which is more than any other known galaxy.
#Astrophotography #seestar #NGC6946 @kat-astro-bot.bsky.social
NGC 6946 was nicknamed the Fireworks Galaxy because it has hosted 10 supernovae over the last century, which is more than any other known galaxy.
#Astrophotography #seestar #NGC6946 @kat-astro-bot.bsky.social
September 24, 2025 at 1:37 PM
NGC 6946 (The Fireworks Galaxy) is a bright spiral galaxy in the constellation Cepheus.
NGC 6946 was nicknamed the Fireworks Galaxy because it has hosted 10 supernovae over the last century, which is more than any other known galaxy.
#Astrophotography #seestar #NGC6946 @kat-astro-bot.bsky.social
NGC 6946 was nicknamed the Fireworks Galaxy because it has hosted 10 supernovae over the last century, which is more than any other known galaxy.
#Astrophotography #seestar #NGC6946 @kat-astro-bot.bsky.social
🔭 M27 - The Dumbbell Nebula is a planetary nebula in the constellation Vulpecula, at a distance of about 1360 light-years and has brightness of magnitude 7.5.
#Astrophotography #seestar #M27 @kat-astro-bot.bsky.social
#Astrophotography #seestar #M27 @kat-astro-bot.bsky.social
September 8, 2025 at 1:13 PM
🔭 M27 - The Dumbbell Nebula is a planetary nebula in the constellation Vulpecula, at a distance of about 1360 light-years and has brightness of magnitude 7.5.
#Astrophotography #seestar #M27 @kat-astro-bot.bsky.social
#Astrophotography #seestar #M27 @kat-astro-bot.bsky.social
🔭 NGC6990 - The Western Veil Nebula is part of the Cygnus Loop, a supernova remnant in the constellation Cygnus. 😀
#Astrophotography #seestar #ngc6990 @kat-astro-bot.bsky.social
#Astrophotography #seestar #ngc6990 @kat-astro-bot.bsky.social
September 6, 2025 at 4:31 PM
🔭 NGC6990 - The Western Veil Nebula is part of the Cygnus Loop, a supernova remnant in the constellation Cygnus. 😀
#Astrophotography #seestar #ngc6990 @kat-astro-bot.bsky.social
#Astrophotography #seestar #ngc6990 @kat-astro-bot.bsky.social
🔭 NGC6992 - The Eastern Veil Nebula is part of the Cygnus Loop, a supernova remnant in the constellation Cygnus.
#Astrophotography #seestar #NGC6992 @kat-astro-bot.bsky.social
#Astrophotography #seestar #NGC6992 @kat-astro-bot.bsky.social
September 2, 2025 at 5:13 PM
🔭 NGC6992 - The Eastern Veil Nebula is part of the Cygnus Loop, a supernova remnant in the constellation Cygnus.
#Astrophotography #seestar #NGC6992 @kat-astro-bot.bsky.social
#Astrophotography #seestar #NGC6992 @kat-astro-bot.bsky.social
Reposted by Ronald Bijtenhoorn
🌟 The May 2025 edition of The Evening Sky Map is ready for download at skymaps.com/tesm/. The PDF includes a Sky Calendar and user-friendly sky maps for the northern & southern hemispheres, as well as equatorial regions. Please share & enjoy exploring the Universe! 🔭
#astronomy #stargazing
#astronomy #stargazing
April 24, 2025 at 1:49 PM
🌟 The May 2025 edition of The Evening Sky Map is ready for download at skymaps.com/tesm/. The PDF includes a Sky Calendar and user-friendly sky maps for the northern & southern hemispheres, as well as equatorial regions. Please share & enjoy exploring the Universe! 🔭
#astronomy #stargazing
#astronomy #stargazing
🔭 Comet C/2025 F2 (SWAN) also captured in the Netherlands! I will give it a try tomorrow morning! 😀
There she is! Comet C/2025 F2 (SWAN) 🥰🥰
It was tricky: low on the horizon, light pollution from the city, and even some thin clouds… but I got her! 🥳 (Egmond aan Zee - NL)
#SeestarS50
It was tricky: low on the horizon, light pollution from the city, and even some thin clouds… but I got her! 🥳 (Egmond aan Zee - NL)
#SeestarS50
April 11, 2025 at 9:24 AM
🔭 Comet C/2025 F2 (SWAN) also captured in the Netherlands! I will give it a try tomorrow morning! 😀
Reposted by Ronald Bijtenhoorn
Een mislukte première voor Spectrum-raket, defensie en ruimtevaart in Delft en studeren op een missie naar Titan. Dat en meer bespreken Thijs Roes, Erik Laan en Luc van den Abeelen in deze nieuwe SpaceCowboys
www.bnr.nl/podcast/s...
www.bnr.nl/podcast/s...
April 9, 2025 at 5:14 PM
Een mislukte première voor Spectrum-raket, defensie en ruimtevaart in Delft en studeren op een missie naar Titan. Dat en meer bespreken Thijs Roes, Erik Laan en Luc van den Abeelen in deze nieuwe SpaceCowboys
www.bnr.nl/podcast/s...
www.bnr.nl/podcast/s...
Reposted by Ronald Bijtenhoorn
Quick video about the newly discovered Comet C/2025 F2 (SWAN) and how to add it to stellarium: www.youtube.com/watch?v=GA6f...
#astronomy #Comets #Space
#astronomy #Comets #Space
Newly Discovered Comet C/2025 F2 (SWAN) and How to Add it to Stellarium
YouTube video by Naztronomy
www.youtube.com
April 10, 2025 at 3:08 AM
Quick video about the newly discovered Comet C/2025 F2 (SWAN) and how to add it to stellarium: www.youtube.com/watch?v=GA6f...
#astronomy #Comets #Space
#astronomy #Comets #Space
🔭 Great challenge for the coming week! 😀
For those early risers, I have added details of what looks like a nice comet, Comet SWAN25F to my Web site. It's about 9th magnitude and sporting a very nice tail with lots of structure.
www.star-gazing.co.uk/WebPage/come...
www.star-gazing.co.uk/WebPage/come...
Comet SWAN25F – Star-Gazing
The SWAN Imaging system has found a new comet. It has not been assigned an official designation yet, so currently known as SWAN25F. It's bright enough to be see
www.star-gazing.co.uk
April 8, 2025 at 9:47 AM
🔭 Great challenge for the coming week! 😀
🔭 Last attempt to capture the Orion Nebula (M42), it slowly disappears into the evening twilight to reappear in the early morning of September.
#Astrophotography #seestar #M42 @kat-astro-bot.bsky.social
#Astrophotography #seestar #M42 @kat-astro-bot.bsky.social
April 7, 2025 at 6:20 PM
🔭 Last attempt to capture the Orion Nebula (M42), it slowly disappears into the evening twilight to reappear in the early morning of September.
#Astrophotography #seestar #M42 @kat-astro-bot.bsky.social
#Astrophotography #seestar #M42 @kat-astro-bot.bsky.social
🔭 The Moon close to the Pleiades (M45)
#astrophotography
#astrophotography
April 1, 2025 at 8:53 PM
🔭 The Moon close to the Pleiades (M45)
#astrophotography
#astrophotography
Compilation of the partial solar eclipse, during the maximum at 12:10 about 24% of the sun was covered.
It was a bit of a challenge to take the pictures between the clouds. 😊
🔭 #seestar #eclips #solareclips #sun #moon
It was a bit of a challenge to take the pictures between the clouds. 😊
🔭 #seestar #eclips #solareclips #sun #moon
March 29, 2025 at 1:20 PM
Compilation of the partial solar eclipse, during the maximum at 12:10 about 24% of the sun was covered.
It was a bit of a challenge to take the pictures between the clouds. 😊
🔭 #seestar #eclips #solareclips #sun #moon
It was a bit of a challenge to take the pictures between the clouds. 😊
🔭 #seestar #eclips #solareclips #sun #moon
I have added two books to my 🔭 astro library this weekend.
I got my hands on a second-hand french version of Rükl's Moon Atlas.
And further I came across 'Planetary Astronomy' by Christophe Pellier to learn more about capturing and editing planetary photos.
Happy reader! 😀
I got my hands on a second-hand french version of Rükl's Moon Atlas.
And further I came across 'Planetary Astronomy' by Christophe Pellier to learn more about capturing and editing planetary photos.
Happy reader! 😀
March 24, 2025 at 7:40 PM
I have added two books to my 🔭 astro library this weekend.
I got my hands on a second-hand french version of Rükl's Moon Atlas.
And further I came across 'Planetary Astronomy' by Christophe Pellier to learn more about capturing and editing planetary photos.
Happy reader! 😀
I got my hands on a second-hand french version of Rükl's Moon Atlas.
And further I came across 'Planetary Astronomy' by Christophe Pellier to learn more about capturing and editing planetary photos.
Happy reader! 😀
Reposted by Ronald Bijtenhoorn
Happy Saturn ring plane crossing day to all who celebrate.
It's #Saturn ring-plane crossing day! A once in a 13-15 yr event when Saturn's rings are edge on, as viewed from Earth, making them appear to disappear! I'm so infuriated that the Sun is in the way meaning no-one will see it! 😡 We'll just have to imagine it 😞
👇The last time it was seen in 1995. 🔭🧪
👇The last time it was seen in 1995. 🔭🧪
March 23, 2025 at 7:55 AM
Happy Saturn ring plane crossing day to all who celebrate.
🔭 First try to capture #Jupiter with the ZWO ASI664MC on my 6” SCT from our backyard
Circumstances were not ideal; 3 months after opposition and Jupiter just visible above our rooftop.
Still a lot to learn about capturing and post-processing but happy with this first result! 😀
#Astrophotography
Circumstances were not ideal; 3 months after opposition and Jupiter just visible above our rooftop.
Still a lot to learn about capturing and post-processing but happy with this first result! 😀
#Astrophotography
March 19, 2025 at 11:03 AM
🔭 First try to capture #Jupiter with the ZWO ASI664MC on my 6” SCT from our backyard
Circumstances were not ideal; 3 months after opposition and Jupiter just visible above our rooftop.
Still a lot to learn about capturing and post-processing but happy with this first result! 😀
#Astrophotography
Circumstances were not ideal; 3 months after opposition and Jupiter just visible above our rooftop.
Still a lot to learn about capturing and post-processing but happy with this first result! 😀
#Astrophotography
Reposted by Ronald Bijtenhoorn
Last night we finally had clear skies again 😍 The Seestar telescope was happily at work, and here’s the result: NGC2237 (mosaic), M44 (mosaic) and M61.
February 2, 2025 at 8:22 PM
Last night we finally had clear skies again 😍 The Seestar telescope was happily at work, and here’s the result: NGC2237 (mosaic), M44 (mosaic) and M61.
Reposted by Ronald Bijtenhoorn
Had another go at #Jupiter last night with my trusty 18cm maksutov in my backyard in Purmerend, the Netherlands. With the Great Red Spot, too. #astrophotography 🔭
Stil have lots of data to go through, so more to come :)
Stil have lots of data to go through, so more to come :)
February 2, 2025 at 1:33 PM
Had another go at #Jupiter last night with my trusty 18cm maksutov in my backyard in Purmerend, the Netherlands. With the Great Red Spot, too. #astrophotography 🔭
Stil have lots of data to go through, so more to come :)
Stil have lots of data to go through, so more to come :)
Reposted by Ronald Bijtenhoorn
The Evening Sky Map celebrates its 25th anniversary today! Over 1,000 issues have been handcrafted and distributed freely to sky enthusiasts worldwide. The monthly map serves both beginners learning the night sky & more experienced stargazers checking what's up each month. 🔭 🧪
skymaps.com/tesm/
skymaps.com/tesm/
December 31, 2024 at 10:33 PM
The Evening Sky Map celebrates its 25th anniversary today! Over 1,000 issues have been handcrafted and distributed freely to sky enthusiasts worldwide. The monthly map serves both beginners learning the night sky & more experienced stargazers checking what's up each month. 🔭 🧪
skymaps.com/tesm/
skymaps.com/tesm/
🔭 M1 - Crab Nebula, remnant of a supernova observed by Chinese and Japanese observers in 1054.
Distance 6500 Light Year; Magnitude 8.4
Photo taken with the #seestar ; exposure time 48 min 😀
Distance 6500 Light Year; Magnitude 8.4
Photo taken with the #seestar ; exposure time 48 min 😀
December 27, 2024 at 3:44 PM
🔭 M1 - Crab Nebula, remnant of a supernova observed by Chinese and Japanese observers in 1054.
Distance 6500 Light Year; Magnitude 8.4
Photo taken with the #seestar ; exposure time 48 min 😀
Distance 6500 Light Year; Magnitude 8.4
Photo taken with the #seestar ; exposure time 48 min 😀