The Great Conjunction – December 20th

About thirteen hours to go… The actual instant when it’s the closest will be during the day tomorrow on the US West Coast. By the time it gets dark here we’ll be about eight hours past. Not to worry – it won’t be enough of a difference for you to notice if I didn’t tell you. As for tonight, it was clear and a million in SoCal.

(As always, click on the image to see it full sized!)

At the 70mm setting on the 70-300mm zoom lens, you can just see a bit of separation still. And a plane going by above it, trailing a red streak in this 1/8 second exposure.

Up close at 300mm zoom, there are moons of both Jupiter and Saturn, as well as a background star that happens to be in the right spot to look like a 5th moon of Jupiter.

(Image from Sky & Telescope’s Jupiter’s Moons app)

Here’s what we’re supposed to be seeing…

…and here’s the center of that second image of mine, blown up to full sized and labeled.

What about through the telescope?

Oh! My! God!! I truly wish I had the equipment to show you how fantastic and amazing it looked. In addition to what I can show here below with my last minute, half assed, gee, let’s see if this might work efforts, in the eyepiece it was razor sharp, crystal clear, with horizontal bands being visible on Jupiter, the rings separated from the planet on Saturn, and Saturn’s second largest moon, Rhea, clearly visible as well as Titan.

So I started playing around with the iPhone camera settings… What did I have to lose?

(Late note – I realize from comments I’ve gotten on Facebook that I haven’t explained yet that the views below, seen through the telescope, are flipped bottom-to-top. THEY ARE! In the images above, which were taken with a camera, bright Jupiter is on the bottom and dimmer Saturn is on the top. In the images below, it’s the other way around. That’s because the optics and mirrors in a Newtonian telescope flip the image – no time to get into it here, Google it if you need, but just remember to see if it’s an image from my telescope or from my camera to orient yourself to how you might see it yourself.)

With a slightly longer exposure you can see the Galilean moons and Saturn is definitely elongated.

But if you go for a shorter exposure and don’t worry about the moons, the rings and planetary disk on Saturn start to come out!

Somewhere in the middle, you get a little bit of both. This is a real tease, making me want to get better at these and get the gear to do it right.

Finally, what happens if I try to use the iPhone video through the telescope’s eyepiece? Why, then you get something like this, which was taken when the planets were getting closer to the horizon and down in the thick air. That means it jumps around a bit and goes in and out of focus, but that also means that there are moments in the 8-second video when you can see things clearly.

Tomorrow night is the moment of conjunction – but of course, that doesn’t end this event. It just means that after weeks of slowly coming together they’ll pass that instant when they’re the closest and then start moving slowly apart. They’ll be visible in the evening sky until about January 10th or so, at which point they’ll be too close to the Sun to be seen. Saturn goes behind the Sun on January 23rd, Jupiter on January 28th, before they both re-emerge in late February in the pre-dawn sky.

Clear skies, happy viewing, I hope all of you get to take a look tomorrow (or in the days following) to see this magnificent sight!