I figure I would do a couple of posts sharing the photos I took of the event as luck smiled upon me and I was able to shoot a number of nights, including the night of the closest approach (December 21st). The two previous posts shared some of the photos, but these posts will go into a bit more depth.
We begin a month prior to the event. November 18th, to be precise, and to be even more precise, November 18, 2020, at 6:15:58 pm (18:15:58) local time (Central/Chicago time).
I’m including the shooting data as much for me as for anyone else. The photo was taken from my driveway and the garage lights are illuminating the neighbor’s trees.
All of these photos will be shown full-size in a SmugMug Gallery (LINK) but you can click on the photos in this post to open a larger version in a new tab or window. (NB: cropped versions are not likely to be much larger as they are shown at 100% or 1:1 crop.)
Frankly, I’d forgotten I had taken photos on this date. I was happy to find it.
So, what are we looking at? Obviously, the big bright thing is the moon (showing a bit of Earthshine<<link). If you let your eyes travel at a diagonal toward the upper left, the first bright spot is Jupiter, and the second, fainter, spot is Saturn.
In previous posts (linked above), I mentioned Stellarium (LINK). Well, I used the program to recreate that approximate view (Note: I’m off by one second because I didn’t pay attention. I could go back and recreate the shot, but there would not be any functional difference from this screen capture).
My neighbor’s trees are not included with the program, but you can see the matching relative positions of the Moon, Jupiter, and Saturn.
Here’s another photo shot five minutes later than the first. It looks pretty much the same . . . but I’m including it because of the track of a passing airplane on the frame ( above and slightly to the right of Saturn).
Also, I didn’t try to capture the faint light of other stars. and neither did I bring my big lens to bear and take any closeups . . . something I did on December 5th.
Again, here’s the matching Stellarium image . . .
HINT: if you click on the photos and leave them open in their tabs, you can quickly switch from one tab to the next and compare the two.
I also took another screen snapshot of the program with settings giving a better definition of the stars, but I had let the clock run, so it’s a few minutes later.
The program’s display is dynamic, meaning the sky keeps changing per Earth’s rotation as you watch, and even shows satellites passing through the field of view (which I use when I want to see something moving in the sky). For the purpose of comparing shots, the time differential doesn’t matter as the relative position doesn’t change.
But, back to the photo . . . I wasn’t sure at the time because I thought they might have been stars, but for the first time that I remember (I don’t shoot the sky all that often, so I don’t have to remember much) — in addition to Jupiter’s Galilean moons — the image I captured shows a few of Saturn’s moons.
As a testament to the D7500’s low light capabilities, if I cranked up the exposure and lightened the photo, I could actually see faint traces of some of the other moons for the two planets. because the images get so noisy, they’re not worth sharing, but it was impressive to me.
So, how do I know those were moons? Well, if I zoom into Stellarium, the moons show up because the program knows that as you get closer to the planets, you’ll see the moons . . . or, you know, I could just switch the names on. But, that’s not what I did.
I use a couple of websites — one of which I’ve shared before — that have applets showing the positions of the major moons for any given date and time.
For Saturn’s moons, I use THIS<<link site. Here’s the position of Saturn’s moons corresponding to the time of the above image.
That tells me that the two moons shown in my photo are Dione (closer to the planet) and Titan.
For Jupiter’s Gallilelan’s moons, I use THIS<<link site. Here’s the position of Jupiter’s moons corresponding to the time of the above image.
Some people might not be familiar with UT (Universal Time)<<link and you can read about it at that link, but if you just want the conversion from UT to your local time, this LINK will help. I’m sure there are other sites, but that just happened to be the one I found first.
So, that photo was during twilight. As mentioned in prior posts, the two planets are fairly low on the horizon by the time they become visible, and with each passing day, they would appear lower and lower. However, on this particular day (as a reminder, December 5th) they were still high enough a half-hour later for the following photos.
While the relative position of the planets doesn’t perceptively change in that span of time, the moons do — as Galileo got in trouble for noting — move. Not much, and not enough to tell between the photos (any difference is likely due to the camera not being on the same location or leveled the same), but if you check the applets I linked, you can see they shift.
One other thing to note is that details of the planets are washed out because to capture the image, I need a long enough exposure . . . or, do I? Well, yes and no. (caution: boring stuff ahead)
I don’t need as long of an exposure when using a shorter (wider) zoom because the lens gathers more light than it does at the longer zoom (a simplistic explanation that doesn’t apply to prime lenses, but I don’t want to bore anyone not interested and anyone interested already knows this).
However, the details will be missing because the wide-angle view will show the planets as mere spots. As I zoom in closer, I should be able to resolve more details, but the longer zoom gathers less light, so I need a longer exposure (or higher ISO).
But, the longer the exposure — while capturing the light of fainter stars — will also wipe out the details of the planets both because there is more light reflected from them than the light of the stars — that light has to travel many years to get here … many, many years — and because I have a stationary setup. Meaning, longer than a few seconds, and I begin to see ‘trails’ and lose definition.
Now, if I wanted to, I could shorten the exposure and capture just enough light to get a more accurate shape of, for instance, Saturn. But, it will be faint. I could crank the ISO, but then I lose some definition to noise AND I still gather more light than I might want. Confusing?
Here’s an unedited image of Saturn at 400mm zoom, 1/30 sec. shutter speed, f/6.3 (as wide open as that lens can be at that zoom), and ISO 200 (minimal to no noise).
Do you see the little speck in the middle of the screen? That’s Saturn. Just enough light to get an image, but no stars around it or any visible moons. Now, because I shoot RAW, I could increase the exposure and the contrast and the brightness and increase the highlights and dance around with a colander on my head and sacrifice a chicken and I could then probably coax out more stars . . . but then, Saturn’s image will look like the ones in the previous photos. meaning, just a bright spot . . .
. . . OR, I could just zoom in at 1:1 magnification and see this:
Yup! That be Saturn, alright, all by its lonesome. It turns out that would be the best such image I managed to capture and better than any in all my subsequent tries. This has to do with a number of things I’ll cover in later posts.
So, the Conjunction part of this post ends here . . . because I want to shift my attention to Orion<<Link. (Don’t worry; I’ll get back to the conjunction in later posts.)
Along with Cassiopia<<Link, Orion was one of the first constellations I became aware of and was able to identify; I always notice it when it’s up in the sky. Yes, yes, the Big and Little Dippers were likely the very first, but Orion seems more special, somehow.
Whatever the reason, as I was shooting the conjunction, I noticed Orion was rising in the East. Still too low for a decent shot, I waited until three hours later, and then . . .
Again, if you are on a mobile device without sufficient resolution or size, just stop and go do something else, otherwise, you can click on the above for a larger version (and eventually visit SmugMug after you finish reading all this).
However, even with a decent screen (not viewed in a bright environment), that’s a little faint. This is a photo a few minutes later where I cranked up the ISO to 3200.
That should be a bit more visible . . . and here’s the Stellarium equivalent.
Well, gorsh durn it all! It looks (almost) the same! Why even bother with the camera when I can sit and look at the sky from the comfort of my desk? Why, indeed . . . oh, yeah; it’s more breathtaking seeing it with your own eyes. Well, at least for some.
“Uh-oh . . . I sense boring stuff coming up!”
Why, yes Bob . . . I aim to bore the snot out of you.
You see, Stellarium has a few features that are fun to play with. For instance, some might have heard something about Orion the Hunter (side link to a story HERE) and that the three aligned stars of the constellation form its belt . . .
You can switch on a few features in Stellarium and learn about constellations, where they are, how to spot them, and help you visualize them.
Let me zoom out a bit . . .
That’s Orion holding up a dead lion (told you he was a great hunter!). If you haven’t yet read the Wikipedia link, don’t forget to do so after you finish reading this. You’ll get a lot of history of how the constellation has been interpreted by various cultures and even its ties to modernity.
Here’s a capture that may be more helpful in helping you find Orion in the sky.
The problem is that most of us don’t live where the sky is a familiar companion. And, even if you have a relatively decent location, you’re likely to see something along these lines (on a good night).
Actually, no . . . you’ll have some light pollution so that even if you see a decent amount of stars, you might look like this . . .
It might be tough finding all the stars comprising the constellation (I think I clipped a few in that photo).
You might be tempted to think a really dark sky would make it easier . . . well, yes and no. I mean, it would if it looked like this . . .
. . . and even if it looked like this . . .
. . . or even with just the pertinent star’s relative magnitude enhanced . . .
. . . but in a really dark location, you’re likely to see something like this . . .
Unless you’ve studied the sky often and in detail, you’d be hard-pressed to identify all of the stars making up the constellation. Fortunately (or unfortunately) most of us will likely go all our lives without experiencing a truly dark-sky location.
But, many of us can readily locate this part of the constellation and the associated stars (even if we don’t remember the names of all of them) . . .
Some folks might wonder about the smudges on those Stellarium screen captures. You might have noticed them in my photos . . .
Well, here comes Stellarium to tell you what those are . . .
Yes, they be Nebulas . . . let me zoom in on a couple (using Stellarium) . . .
No matter how much I zoom in on my photos, they don’t look like that (although I’ve not tried to specifically shoot them) . . .
. . . however — and coincidentally — the Cosmic Focus blog (LINK) just did a post about the Orion Nebula (Messier 42).
Before you head over there, I have one more photo to share from December 5th . . .
“What the heck is that supposed to be?”
Here, this might help . . .
“OK, that’s Mars. That’s cool . . . but what’s up with the other stars?”
Well, Bob, let me zoom out and show you a bit more . . .
And here’s why I photographed it . . . LINK. That’s right . . . you can use the Great Square to figure out the limit of the magnitude of the stars you can see with the naked eye (remember that higher numbers mean fainter stars). Per the article, count the number of stars you can see inside the square and it gives you a good rule-of-thumb for how polluted your sky is.
These other articles have more information regarding visible stars (how many there are and how many you can expect (optimistically) to observe without the aid of an instrument) . . . LINK, LINK, LINK.
As you can see from my photo, the camera can see pretty good . . . me? I didn’t see any stars inside the Great Square of Pegasus. Good thing, then, that I have a camera.
Here’s a gallery of the above . . . that’s another way you can compare photos to their Stellarium counterparts.
That’s it. This post has ended . . . except for the stuff below.
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