Memories of Jupiter

Do you recall the largest planet of all?

Jupiter’s prime viewing season in 2017 has long past, but it should still be visible a little after sunset if you want to get a final glimpse of it this year in the evening sky.

Back in June, when Jupiter was high in the sky, I embarked to sketch the planet a few times, intermingled with on different nights opposite my digital photography of it.  Sketching at the telescope is an art for which I am barely a novice, but I am taking steps to improve my drawing skills in hopes of better future drawings for Jupiter, the Moon, and Mars.

I did mentioned in an earlier blog post or comment that I would post my sketches.  So better late than never, for better or worse, here they are, further below.  Note that I list the eyepiece filters used.  An objective I had this year was to determine which filters are best for seeing Jupiter’s details.  In my final sessions, as I was getting more comfortable making out the planet’s finer details, I decided to test each of my filters so that knew for years to come which filters will help my observations.

It is entirely possible that my filter opinions are just that, and yours may be different.  But if you are inclined to observe Jupiter someday at the telescope, here is my little guide on which filters I prefer.  The numbers, in case you are unfamiliar, as the standard Wratten numbers to denote filter color or type.

  • #12 Yellow – Very good, great band contrast
  • #23 Orange – Very good, can see band contrast
  • #25 Red – Bad, can only see the primary bands a little
  • #58 Green – Good-to-ok for band contrast
  • #80A Blue – N/A, filter was dirty, needed to clean
  • #80A Medium Blue – So-so (maybe results would have been better if Jupiter was higher in the sky?)
  • #96 Neutral – Very good, a little less bright but can see bands easily
  • Mars filter – Good, nice contrast and, in particular, the Great Red Spot really popped out

So I recommend #12 Yellow, #23 Orange, #96 Neutral, and Mars.  I have to recheck my #80A Blue filters next year.

And now, onto the Jupiter sketches…

Jupiter on June 1st, 2017.

Jupiter on June 2nd, 2017.

Jupiter on June 10th, 2017.

Jupiter on June 27th, 2017.

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Constellations III: Of the Summer Triangle

Click to see the full-sized hi-res image!

A few days after I searched for Pluto, I chose to forgo my telescopes for one clear evening and play with my digital camera.  The Summer Triangle is straight up in the evening sky right now for several hours after sunset.  As Jack Horkheimer used to say, “Keep looking up.”  This time, take his advice literally and you will see the magnificent asterism defined by the stars Altair, Deneb, and Vega.

This image was taken in a similar fashion to my prior wide-field constellation pictures, like Leo, where I took dozens of light, dark, and bias frames and then created a composite in DeepSkyStacker.  For this new image, though, I went a step further.  I have been searching for a way to accentuate the stars based on their brightness, short of manually blowing them up.  I believe I have uncovered a technique to get the desired effect.  You can easily make out the three main stars along with other stars/patterns in descending order from their apparent magnitudes.

I must admit that I was mildly shocked at how many stars are shown.  Are those really stars, or image noise?  As the images were taken straight up, to the darkest part of the sky, it seemed plausible.  Also, the Milky Way runs right through the Summer Triangle.  You cannot see the Milky Way in my picture, as I don’t think it is possible to capture in my light-polluted area without longer exposures and an equatorial mount.

In checking as many detailed online star charts as seemed reasonable, I do believe those dots are all stars!

Remember that an asterism is a pattern of stars, versus a constellation, which is a generally accepted “official” pattern.  The Summer Triangle is an asterism (a triangle, duh) but it has several constellations in and around it.  How many constellations can you see and name in this picture?

My Hunt for Pluto, Part II: The False Star

Figure 2.1: My sketch of the area surrounding Pluto on September 14th, 2017.

“I really want to try to find Pluto again one more time this season…If I do get a chance, I will post a follow-up next month.” – Me, August 29th

With the Moon safely out of the way and a clear sky opportunity available, last week I resumed my quest to find Pluto.  Much of this post relies on information from my first attempt last month, and so I will be referring to that post frequently.

Recall that I leveraged the easily recognized “teapot” asterism in the constellation Sagittarius to star hop over to the approximate location of Pluto.  The main anchor star in the area of Pluto, both last month and now, is Albaldah.  Albaldah and a few nearby neighbors are the last stars I can see unaided.  So targeting Albaldah with my telescope was the first order of business.

The journey past Albaldah was guided with the help of both the Stellarium app on my tablet as well as my prior post.  I should note here that the “app” version of Stellarium is far less detailed than the PC version when investigating such faint objects in small spaces.  Further, based on my two observation sessions, I now believe there is an error in the PC Stellarium map, which I will explain in a moment.

Using the same 2″ Q70 eyepiece as last month, I quickly found HIP 94372, the 6.35 magnitude “mini-anchor” star near Pluto visible only with my telescope.  From HIP 94372 I located the 8th-magnitude star pattern I nicknamed k-lambda, assuring that I was in the correct vicinity.

At this point I was aggressively looking at the images from my prior blog post, the Stellarium app, and my telescope eyepiece.  I decided early on that it would be best to switch to a higher magnification than the 2″ eyepiece allowed, so I changed to my 1.25″ 14.5mm Planetary.  This eyepiece illuminated a much clearer view around HIP 94372.

Then I began sketching, referring to Stellarium only to assure that I was still in the location I wanted to be and drawing at the correct perspective size.  In my drawing above (Figure 2.1) it is difficult to see which stars are faint and which were really faint to the point that averted vision was necessary to see them.  The three stars I labeled as #1, #2, and #3 were the brightest, forming a triangle.  The three arcs were the approximate boundaries of the eyepiece.

With my sketch partially done, I had to make an assumption – that the small star close to HIP 94372, identified only by the Stellarium PC version, does not exist.  This probably threw me off last month, at least a bit, in determining if I truly had seen Pluto.  It is listed at magnitude 9.10, which should be easily visible, especially at the higher magnification I was now using with the 14.5mm eyepiece.  A 9.10 star should only be slightly dimmer than k-lambda, as well as the three stars forming the main triangle in my sketch.  And the few stars I drew around HIP 94372 are extremely faint, well past magnitude 9.  So either this star does not exist or its magnitude is incorrect in Stellarium.

Figure 2.2: Is this star really there?

Returning to the Pluto hunt, I knew it should be located within the three-star triangle I sketched.  In the figure below from Stellarium, I edited out the false star, as well as flipped the image to correspond to what I drew at the telescope that night.  Pluto is represented as a very, very tiny dot:

Figure 2.3: Pluto and surrounding stars as shown by Stellarium for September14th, 2017.

Remember, again, that most of these stars are very faint.  To help gauge where Pluto might be, I imaged a micro asterism forming a dipper or serpent, which starts at the star HIP 94338:

Figure 2.4: Identifying the serpent and “bright” stars.

I could see this dipper easily at the telescope so long as I knew where HIP 94372 was.  I also knew, then, that Pluto had to be just below (actually above, but the telescope reverses the image) this dipper and between HIP 94372 and HIP 94338.

Did I actually find Pluto?  I identified, at the telescope, three possible candidates, all hard to see without averting my eye a bit.  That night while still at the telescope, I drew an arrow pointing to the one I thought was most likely.  The other two candidates were to the right, the nearest dots above and below the one pointed to by my upward sketched “likely Pluto” arrow (see Figure 2.5).

Here is my sketch again, this time with the serpent/dipper lined, the three bright stars circled in orange, and the dot most likely to be Pluto, as determined afterward by comparing to both versions of Stellarium (iPad and PC):

Figure 2.5: My sketch with the most likely candidate for Pluto circled in yellow.

The best way I can confirm/reconfirm which dot was Pluto would be to sketch the area around HIP 94372 once Pluto has moved significantly.  Unfortunately by next month (after the next Full Moon passes), Sagittarius and Pluto may be too low in the sky for me to draw again, mostly due to the impacts of light pollution as they near the horizon.  And so, true final confirmation may have to wait a good seven to nine months, as the Earth and Pluto revolve around the Sun, beckoning the dwarf planet back into our East sky by late Spring 2018.

Alternative Moon Perception

The Moon…as you have never seen it before!

This is the exciting finale to a trilogy of posts about my August 30th Moon adventures.  The first showed the Waxing Gibbous Moon from that night.  The second explored several of the Moon’s craters.  And now here is the story of what came next.

As I finished up my astrophotography for the evening, I detached both the camera and eyepiece setup from my Dobonsian’s focuser.  I had, just moment before, been taking my last pictures, so the Moon was still in the telescope’s field of view.  With the focuser empty, I noticed the very bright light emanating through, like a flashlight.  This was, obviously, the Moon’s light still reflecting from the primary mirror, off the secondary, and through the focuser hole.

I have observed this “flashlight” before, but usually considered it for only a moment as I would be in the process of packing up my equipment for the night.  But on this pleasant evening for the 30th day of August, I decided to play with the light a little.  I put my hand in front of the focuser and could see the blurry image of the Moon upon it.  Moving my hand around allowed me to focus the Moon, directly on my hand.

I thought this was the end of the exercise.  But when I put the dusk plug back onto the focuser, Moonlight was still shining, this time through the translucent plastic.  It is a very simple cap, and if you are unfamiliar with these telescope dust plugs, they look like this.

Adjusting the focuser allowed me to bring the Moon into focus, right on the cover of the dust plug.  It was a strange sight.  It reminded me of the small view screens that attached to some home film projectors in the 1970s.

The Moon, but not the Moon.  Quickly I detached my smartphone from its mount and took several pictures of the phenomenon.  The above is one of those images with only minor post-processing.  The diagonal streaks across the Moon are the grains of the dust plug’s surface.

I got a lot of value out of that Moon observing session.  Right now, the Moon is waning and nearing the next New Moon.  Unfortunately my weather forecast is cloudy through the weekend; I want to get back out there and find Pluto one more time this year.

One More Name Change

For the last few weeks since I changed my display name, I noticed that it was too long to fit in many of the standard field sizes we are accustomed to.  I thought about shortening it by simply dropping “Backyard,” but that made the name too common.

So I came up with a slight variation that still has strong roots in the blog, and manages to be comfortably shorter.

As last time…same blog, same author, new author name!

Discovering the Moon’s Craters

Section of the Moon on August 30th, 2017.

When I photographed the Moon on August 30th, I felt now was a good time to start examining it at a closer level.  Having only attempted crude drawings of craters previously, I wanted to see how high I could push the magnification of my Dobsonian reflector.  So I replaced the 17mm Plossl eyepiece used for the full disc image with a 7.5mm and Barlow lens to see what I could get.

(I should note here that I was using my smartphone for pictures, hence the afocal method of putting the camera directly to the eyepiece.)

With that telescope, this eyepiece setup magnifies about 333 times!  Although well within the theoretical maximum for a 254mm aperture, it does present challenges with the atmosphere and, closer to home, vibrations when attempting to get a steady photograph.  Many of my attempts came out motion blurry.

The situation presented itself as the ideal opportunity to study the Moon map that came with one of my equipment orders last year.  This particular section of the Moon is near its Southern pole.  At first, I had no idea what I was looking at, as the map and my image appear a tad different due to shadows.  Plus, there are a lot of craters, too many to count!

To pinpoint these specific craters and determine their names, I performed a modified approach to star hopping, but of course for the Moon.  Checking the map, I first leveraged the easy large Mare in the North, then from there simply hopped from large crater to large crater, until I arrived at the location of my picture.

In learning these names and locations, I was humbled to realize how little I know about the Moon.  I have taken lots of pictures for over a year but have never studied the surface.  How does the saying go…I hear but I do not listen?  Surely this is the equivalent for sight.

My embarrassment started when I had no idea the famous Tycho crater is sitting right there in my picture.  It has that internal shadow with a center protrusion.  Below Tycho, the largest crater shown is Clavius, a name I know I have heard before.  It has several smaller craters within.  Maginus and Moretus are also visible.

Here is the same picture, this time with the craters labeled:

This exercise has kindled a desire for me to learn more about the Moon and truly see it in all its amazing detail.  I now know and have seen four craters.  Hundreds more are out there waiting!