Sunday, June 25, 2017

NGC5866, Lenticular Galaxy in Draco

Even though there is a set location for M102 in most charts, books and software like Stellarium, there will always be an eternal discussion about where it should have been located. All this story started back in Spring of 1781 when Monsieur Mechain claimed to discover it, share the information with Charles Messier and then 2 years later retracted his discovery (Here is the whole story).

Long story short, later there was theories about it: some of them would say that it was a false-positive, but others that there was a typo in  describing the coordinates. My favorite and the one I found more reasonable is that the typo was writing the Greek letter : Ο (Omicron) instead Θ (Theta). Both stars in Bootes, but they are 35 arc degrees separated from each other. A fundamental error if describing the location with numbers, but a simple trace in the letter that mislead the location.  

Anyways, if the right description is a nebulous object between the stars Theta Bootes (Asellus Primus) and Iota Draconis (Edasich), then I was in the right spot. There is a group of 4 galaxies that would fit in the description, but the brightest is NGC5866 so that is the one I saw and that most material agreed to be M102.

Taking my eyepiece to that spot wasn’t difficult. I started on Edasich and hopped only three arc degrees towards Asellus Primus and then looked around 1 arc degree to the east for the smudge.  At the time of the observation, I only had my 40mm eyepiece so I used it adding a generic 2x barlow and the results were as you can see in the sketch: an obvious scratch of light with a buldge in the middle.

Some time later, in the morning of May 28/2016 I saw it again and this time using my eyepiece Luminos 15mm (100x). I described as a small and fairly bright oval. I guess it isn’t difficult to see under suburban skies so all I have to say is why not to go out and try?



Clear skies,



LG



Edited by: Jennifer Steinberg (editor in chief). 



SOURCE

Thursday, June 15, 2017

Cassini, The Grand Finale

Today is 15th of June and in exactly 3 months the spacecraft Cassini will finish its 20 year mission, crashing into Saturn’s atmosphere. As the mission continues it’s diving while orbiting Saturn, it is giving us the best images we have ever seen and providing unique and new information of the ringed planet. This is how I ended up wanting to share my first observation of the Cassini Division, the biggest gap between the rings A and B. This is also my last entry from China because in exactly one week we will be moving to US and looking for new adventures, new skies and more fun.

I usually try to share a sketch that shows a realistic eyepiece view, but this time I am going to share the original raw sketch made in the field, while I was observing through the eyepiece. To have a reference of the equipment, I was using my Celestron 6SE tube with my most powerful eyepiece, a 9mm Celestron X-Cel LX (166x).

This observation was made on the 21st of March 2016, more than 3 months after I got my telescope in China. I had seen Saturn before, but honestly I was a little dissapointed because I could not see much detail compared with what I had seen in the beginnings with my Celestron Astromaster 130EQ from Bogota, Colombia.  

That night was special, though. The seeing was good enough that I could throw into the focuser the eyepiece and have a sharp view of Saturn. I kept staring at Saturn for some time and then magically it appears, what I though it was, the Cassini division. It was not very evident, but using averted vision and concentration I could notice a detached piece of ring on both of the edges. I can compare the resolution of the image with a small fracture (or crack) in an X-ray. Doctors could see it easy, but as a patient, one has to know where it is and also what to look for.  This skill is giving by knowledge and experience.  

I sketched it with the most detail I could, adding notes and all kind of stuff that would help me to check later on my computer. When I finished the session and headed back home, I researched for it. It was in fact the Cassini Division, the gap of 4800 kms that was just an small crack in the rings as seen in my telescope and I was seeing it for the first time in live view mode! Funny fact is that it was discovered more than 3 centuries before with a much smaller (only 2.5”) eyepiece but no body could take away my excitement.

Now, you can use a smaller telescope, trying to get it and let the world you replicated Giovanni Cassini’s achievement, but also you can choose to enjoy those amazing images and videos that Cassini's mission has prepared for us. Here is the link: Grand-finale-orbit-guide.


For now I have to say good bye to my wonderful skies in Lijiang and hope US bring us plenty of clear and dark skies.




LG




Edited by Jennifer Steinberg (editor in chief).

Tuesday, June 6, 2017

NGC 1851, Globular Cluster in Columba

Fairly bright, easy to locate and perfect to be seen in binoculars, C73 or NGC1851 is a class II globular cluster (GC) in the southern constellation of Columba. Being a class II GC means that is has a fairly compact core which is precisely why it is bright enough for binoculars. If Charles Messier would have access a couple of degrees south of his location, I could see NGC1851 in his list of “like comets” DSOs.


Columba is a small constellation neighbor of the well known Canis Majoris, where Sirius resides. If one connects the dots (stars) is the right way and with some imagination, it would certainly resembles a colibri, but its name means dove in Latin so let’s say it looks like a landing dove.


The globular is couple of arc degrees south-west from Phact,a 2nd magnitude and the alpha star of Columba. Under my Bortle 5 skies it was easy to find in binoculars and it looked like a fuzzy round ball with some fuzz around. 




Definitely a good target to catch in the south even with a pair of binoculars.



Happy hunting,



LG



Edited by: Jennifer Steinberg (editor in chief).