Monday, December 21, 2020

The Christmas Star

Saturn and Jupiter Conjunction 2020

 I think everybody agrees that 2020 has not been a good year.  For us, there has been challenges and more challenges.  In September of this year, we moved to Bakersfield, CA because of the fires in Boulder Creek.  Thankfully, our stuff survived the fire and my telescope with it.  The smoke does not seem to have damaged the optics, but other than that, my scope smells like BBQ (or used to) everything else seems all right.

 So, I was disappointed with my previous location because most of the sky was blocked by huge redwoods.  Here, we have plenty of sky, but not enough darkness. The air is also not as clean as in the mountains so transparency has not been the best.  I think this is a Bortle 8/9 zone and there are tons of ambient lights around at night. We rented an apartment so the whole situation has kept me away from the stars. Fortunately, the planets don’t need much darkness and since it has been advertised in the media, I could not miss the chance to check this amazing conjunction of the two gas giants: Jupiter with its Galilean Moons and Saturn with its rings. 

My apartment’s entrance faces the southwest so I have followed these two for a while. The days and nights here in the San Joaquin Valley, seem to have few cloud activity so it was a good setting to enjoy this celestial show. On the 20th, they were so close that I took the scope out and gave them a try. Quite a view: Jupiter was exhibiting all its four Galilean moons and because of a background star, it appeared like there were five. We enjoyed the show for a while, try some pictures with the phone and called it a day. Today, on the 21st, I wanted to spot the couple still in daylight so I could take a better picture with my phone. I just shot at the eyepiece without any adjustments. The problem with the moon and the planets is that they are so bright, that the picture at the home looks overexposed. I am not much into Astrophotography so I try my best, but not with much effort.

 At 5:15 local time (GMT -8), just a few minutes after the sun had set and still in daylight, I spotted the shy dot of light. It was so dim against the bright background that the phone could not detect it when I tried to get a picture. I pointed my scope  at it and check on the 40mm eyepiece. There it was: both planets in the vast FOV. Bumping up the magnification to 100, I could see Jupiter’s bands. I went on to 166x and 332x (with a 2x Barlow), but the seeing was bad. The planets were boiling in the FOV. My favorite view was at 100x, with a stable view that could give me enough details on the planets, but I decided to put up a digital sketch (using the phone picture) for the view at 166x. Maybe I should not say it is a digital sketch, but a touched up picture. Lol

 Anyways, here it is and so is the picture I made with my phone of the scene. I could still split up both objects with just my eyes. They made a wonderful pair to wrap up as a Christmas present!

 


Merry Christmas to all,

 

LG


Edited by: Jennifer Carvajal (editor in chief).

 

Thursday, April 23, 2020

Lumicon UHC Filter


Visual comparison in M97, Owl Nebula

There had not been much activity under the stars, in part because of  other stuff that keep me busy (AKA Motorcycles), but also because I got bored of seeing the same star patterns in my little window in between the redwoods.  However, some time ago I decided it was time to get a nebula filter and following the recommendations of the prairie astronomy club 1, I bought my very first filter: a Lumicon UHC Filter. I think it is a first generation, as I bought it pre-owned from a seller in Cloudy Nights.

Some days later, I got the filter in the mail. A1.25” ring with a shiny silver finish. The box has a sticker that tells the following information about its transmission nebula lines: Oxygen-III 496nm 95%, Oxygen-III 501nm  93% and H-Beta 486 nm 96%  (this last and the percentages were hand written so I had to confirm with the technical specs). When I look through it in the daylight, everything looks greenish and I think I could see some flaws in the glass. I don’t think these will affect the performance at least with visual only.


I tried it out a few nights later on every single object I could target in my tight window. It was mostly galaxies so I got disapointed really quick because it did not show any visual improvement, but a darker background and dimmer stars and the DSOs  themselves.
                                                                                                                                                         
More time passed by. Clouds, rain, the moon or my back pain were in my way so not so much stargazing lately.  Clear night, moonless and not so cold so I decided to give it a try. Near the zenith I could see stars up to 5th magnitude with my eyes alone.  I think I got a good transparency, but a poor seeing (Polaris was flickering at low magnification). Seeing did not really matter because  I was not going to try for a planet. In fact, I can’t see planets from my location. They all hide behind the trees.

I waited until the polar bear  (AKA Ursa Major) was mostly out of the trees and went straight to Merak (βUMa). From there, it was just one step to M97. I have to mention that I also saw M108, The Surfboard Galaxy and the view was very pleasant.  Finally, I focused on M97. With my 40mm eyepiece I could see it like a ghostly circle. It was bright enough to be perceived with direct vision. This time, like the last ones, I could not see the eyes of the owl. I added more magnification, first with my 15mm Luminos grenade, but the light coming from the PN was too dim to fulfill the raise in magnification so I could only perceived it with averted vision. Then, I tried again 40mm, but this time with the filter screwed to the back of the eyepiece: background was definitely darker, less stars visible in the FOV but the PN remained intact.  In fact I think it looked brighter, but I know that was just a trick of the mind. Immediately, I tried the filter in communion of the 15mm but no luck. It was actually harder to see than when I used no filter so I abandoned the idea if using that much magnification with this specific object.

When I had spent enough time contemplating the nebula with both filter and no filter, I decided it was time for a sketch. First, I did an unfiltered sketch and then I used it as a template to put key stars on my filtered sketch. I tried to be as  accurate as I could, but since it was not a side by side comparison, it’s more like an approximation of the view. The mind and the eyes are deceived, specially in low light conditions, but what is important to know here is that the filter works with PNs. In the future, I will try to add more PNs to the records of this filter. My goal is to be able to check the southern skies where the most beautiful nebulaes are laid.



During this quarantine I wish you the most dark and clear skies!


LG



Edited by: Jennifer Carvajal (editor in chief). 







Tuesday, November 12, 2019

The Sun and the planet


Transit of Mercury 2019

Digital Sketch. Click for extra size
This was the last one of these rare events for more than a dozen years and despite running short on time, I managed to see it through my 6 inch telescope and a homemade solar filter (click here to see it). I know I could have seen it from NASA website live, but there is nothing like being under the sun itself with my own eyes on the eyepiece, looking at that tiny dot in a crusade across the giant yellowish fireball.  

Here in the west coast of US, we could not see the whole 5 hours plus transit, but about half of it and I personally could only witness a half of that half because here in the San Lorenzo Valley, the sun rise had to overcome the height of the mountains. Despite that, the sky was in perfect mood to let the sun shine in all its magnificence so I had no excuse to miss the celestial event.

I started with my Omni 40mm eyepiece to get 37.5 times the image in the eyepiece and from time to time switched to the Luminos 15mm (100x). The low magnification eyepiece allowed me to fit the sun in the field of view while the Luminos allowed me to concentrate on getting the planet’s shape right. One thing I noticed is that the eye relief is even further back from the eyepiece. I haven’t studied the concepts of optics, but I imagine it is because our pupils are fully contracted.

Spotting Mercury was an easy task. There were no visible sunspots and the little dot was dark and round. To be honest, I have never seen the planet's shape before. One thing that blows my mind is to know that the temperature in that "dark zone" is minus 290F (-180C) while in the other side is 800F (427C). Something similar to summer here in the bay area in California: freezing in the morning but hellish in the afternoon.  One has to really love extreme temperatures to move to Mercury or California.


For those of you who missed it, you can hope to be still in shape for the next one in 2032 or go to NASA’s website and see a full HD recording of it.


LG


Edited by: Jennifer Carvajal (editor in chief)