Waiting for Winter to Reopen the Sky

Ice-covered Lake Michigan this winter.

I wish there was more to say and show from the past few weeks, but the weather has not been cooperating.  Cloud-blanketed days and nights intermingled with furious snow bashings have created a mid-Winter with little time for anything beyond work and shoveling.  But I keep my back deck snow-free in hopes that a prolonged break will come one evening and I can get either a telescope or camera out for at least a brief time.

There are a few matters to report.  First, we are now in prime time viewing season for Orion.  From the northern hemisphere, it’s high in the South around 8 to 9 o’clock.  I very much want to take a wide-field view of this constellation, especially since I recently bought a better wide-field lens that I am eager to try out.  I did catch a brief glimpse of Orion last night through a break in the clouds, but certainly not predictable or long enough to warrant getting equipment set up to photograph.

Over the weekend, in between my snow removal shifts, I was up very late, around 1:30am, and noticed to the East that Jupiter was already visible through my trees.  This is great news as it means opposition is rapidly approaching, and in another one-to-two months it will be available for observation and photography at reasonable evening hours once again.

Finally, all the snow in my area made we wonder if my neighbor’s buried outdoor lights would lessen the area’s light pollution for the time being.  With a small break in clouds last night, I did look up for a few minutes, but did not notice any difference.  My guess is that any mitigation of pollution due to covered lights is offset by the highly reflective white snow cover.

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Morning Moon and Jupiter

Click for the full-sized image.

December 14th, 2017, 5:05 a.m. local time

In a partial attempt to stargaze earlier than Jim R for one morning, I caught a great view of a very Waning Moon rising in the East, with a bonus of Jupiter following along.  You can see Jupiter a bit to the lower right of the Moon as it peeks just above a tree branch.

Frequent readers of this blog know that I mention my view of the East being blocked by trees.  Here you get scope of that blockage, which of course alleviates some in the Winter months.  I enjoy watching Orion and later Sirius ascend through this netted mosaic on clear December evenings.

Jupiter is back! For me, at least…

Position of Jupiter and its moons on December 5th, 2017 06:25 CT.

December 5th, 2017, 06:25 a.m. local time

Tuesday brought in a very clear morning sky.  For the past several weeks, as I’ve let my dog out in the mornings, I have been scanning the East dawn sky for Jupiter.  I finally found it, sticking out high above my largest tree.  Welcome back, old friend.

If you observe Jupiter and stars for any amount of time, you learn that Jupiter is “big” compared to any star.  This is not a trick of its brightness.  As seen from Earth, Jupiter has an angular diameter roughly between 29″ and 51″.  For comparison, Betelgeuse in Orion has a angular diameter never above 0.060″.  So at Jupiter’s smallest, you would still have line up over 483 Betelgeuses to reach the diameter of Jupiter (as seen from Earth)!

I thought I saw a cluster of light immediately to the right of Jupiter.  Could that have been a moon?  Later, I looked up the Jovian moon positions for this exact time, and I found it interesting that Io, Europa, and Callisto were all clumped together on Jupiter’s right, at that moment.  I am not entirely sure if I really saw the combined light of three moons, but it is pretty cool to think that I may have.

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.

Jupiter Animations 2017

First, a bit of housekeeping.  I have not been posting a lot this month, but that does not mean I have not been stargazing.  On the contrary, the amazing weather my area has had for the last few weeks led me to take advantage of it as much as I can.  For example, this week I did a triple feature with my telescope: first imaged Jupiter, then did some DSO searching, and finished with Saturn imaging.  All under a clear new Moon sky.  When I do take pictures, I try to push them to my Twitter account, just because it’s the faster way to post them.

And speaking of housekeeping, this post is a much delayed matter I finally got around too.  On May 31st I took a good sample set of Jupiter images to attempt an animated GIF.  I shot five video sets all about 15 minutes apart.  The above is Jupiter alone.  As you can tell, I do not have an equatorial mount, so Jupiter was in process of still ascending into the night sky at the time I took the videos.

While the planet came out pretty well, unfortunately this was a terrible time to include the Galilean moons.  The only one that was reasonable close was Io.  And bad for Io, it was at the edge of its orbit perpendicular to Earth, so over the course of that hour, it appears to have hardly moved.  See for yourself:

Obviously this second animated GIF is overexposed in order to show Io.  Given that I do not have an equatorial mount, I doubt I will be attempting this animation exercise next Jupiter season, preferring to focus on observing, still photography, and sketching.  If anything, I now know the approximate radius of Io’s orbit through the telescope.  Still, I am glad I attempted this exercise as it is one more achievement to cross off my astronomy to-do list.

Short Animation of Io, Jupiter, and Europa, May 16th

On the night of May 16th, despite high winds I attempted to put together a sequence of Jupiter images to make an animation.  I took video approximately every 20 minutes for six capture sessions in total.

The above animation is only showing two of those six final images.  Problems with the others were different light intensities and increasing cloud cover.  For reference, here are the first five images so you an see what they look like.  The above animated GIF was taken from the second and third images.  The sixth image is not shown because it was simply garbage due to the clouds by that time.

Session #1

The sky was by far the clearest during the first capture session.

Session #2

Session #3

Session #4

Oh look above, there is Ganymede!  It just popped out from behind Jupiter!

Session #5

You can see the quality of this final image is noticeably degraded from the prior four, due to the encroaching clouds, which made the sixth session unusable.  Also observe that Ganymede moved a little to the left across the 20 minutes from the fourth image.

(And in case you are wondering, at this time Callisto was way to the right of Jupiter.)

A Montage of Jupiters from the Past Week

My best Jupiter yet?

Astrophotography results depend on many variables.  The stability and visibility of the Earth’s atmosphere.  The telescope used, along with its mount.  The camera.  The focus at the eyepiece.  Exposure, ISO, and other digital camera settings.  Post-processing setup and techniques.  The skill of the astrophotographer.

This past week I was out each night with my telescope thanks to the benefit of clear or at least decent skies for planetary imaging.  It is still Jupiter’s time for 2017 and I am trying to take advantage of every night possible.  My main telescope (10″ homemade Newtonian reflector on a homemade Dobsonian mount) is not an imaging scope.  My camera, a Canon EOS Rebel SL1, is intended mostly for Auto mode pictures at kids’ birthday parties (but it is super light – a prime consideration for balance on my Dob).  With no mount tracking beyond my own steady hand, I can only get about 25 seconds of video before Jupiter moves out of a stationary field of view.

Post-processing is another matter entirely.  It is more art form to properly stack and extract image detail from PIPP, AutoStakkert, RegiStax, and Photoshop.  It is great that these computer tools exist, but the only way to fully appreciate their capabilities is through trial and error.

The above image, taken this past Saturday, may be my best attempt at Jupiter so far.  Of note is that detail, a little, is visible within the Great Red Spot.  Also, this is my first image that left me confident in using AutoStakkert’s Drizzle (enlarging) function.

As I processed my Jupiters this week I posted what I thought were the best of each batch to Twitter.  Here are the several I have not posted about previously on this blog:

This one is neat with Io’s shadow:

Last is a smaller scale version, with slightly different editing, of the image posted at the top:

Merging the Telescope World with the Real World

From left to right: Moon, Callisto, Io, Europa, Jupiter, Ganymede. Click to see the full-sized image.

As mentioned previously, I took several different types of photographs the night of Sunday, May 7th, when the Moon and Jupiter were close.  One of these perspectives was by mounting my digital camera on a tripod to get a wide-field view of the Moon and Jupiter together.  I took many images with different exposures and ISO settings.  Here is one such raw image:

Click to enlarge.

Here, you see an overexposed Moon along with Jupiter.  This shows the distance between the two at 05/07/2017 21:20 Central Time, approximately.

The important aspect of this picture is that it captures all of Jupiter’s Galilean moons.  If you click on the image, you will easily see three of them – Io, Europa, and Ganymede.  Callisto is there, or at least, is there in the raw TIFF image.  You will have to take my word for it that Callisto is there, just very faint.

How do I know which moons are which?  The easy way I follow is to use this Jupiter moon tracker, plugging in times and dates when I take my pictures.  If you enter the time stamp I wrote above, you will get this:

Now while my original source image is nice, I knew I could improve upon it with other images taken that same night at my telescope.  After accentuating Callisto’s brightness a little so we can see it, I used Photoshop Elements to carefully cut out Jupiter and its four moons.  I then overlayed these into a properly-exposed wide-field Moon image.

Next, I wanted to get a good Jupiter into the picture, since the planet itself is overexposed in all my tripod images.  I created the following image from stacked video at my 10″ Dobsonian:

I will shrink this good Jupiter to overlay into the main picture were the bright overexposed Jupiter resides.  But I also wanted to get the planet’s angle right relative to the moons.  So I imported as a temporary layer this other picture I took on Sunday that I previously wrote about:

This “moon” image is the perfect gauge, first to align with the native orientation of Io and Europa in the main image, and then to align the good Jupiter with the moon image Jupiter.  With the proper angle, I then overlayed this good Jupiter on top of the overexposed Jupiter, shrinking it a bit to compensate for the over-brightness of the original.

The final result is the image at the top of this post.

As a final perspective, I used the telescope Moon image I posted earlier and overlayed it in, and then moved the Jupiter system next to the Moon.  This gives you an idea of how wide an area Jupiter and the Galilean moons take up in reference to our Moon:

Click to enlarge.

That’s all for now. I am hoping with the Moon waning over the next week that I will be able to take more constellation pictures, and possibly a few deep sky objects.

Jupiter and Two Moons

Io (left), Europa (middle), Jupiter (right). Taken on May 7th, 2017.

May 7th, 2017, 10:25 p.m. local time

Apparently it is possible to get Jupiter and its moons into the same picture.  You just have to increase the ISO setting.  For the above picture of Io, Europa, and Jupiter, I cranked up my digital camera’s ISO to 1600.  Normally I have it at 400 or 800 for Jupiter.  It leaves Jupiter slightly overexposed, but I think it is a good trade-off given the objective.

In case you are wondering, Callisto and Ganymede were much further out from Jupiter at this time, one on either side.  I have a special treat for later on to show this from another perspective.