The Beauty That Was Last Night’s Eclipse

With the moon inside Earth's shadow, the sky quickly turned dark again. Stars, stars and more stars, including the Milky Way (at right) in the constellation Aquila. Credit: Bob King
With the moon inside Earth’s shadow (lower left), the sky quickly turned dark, revealing thousands of star and the Milky Way (at right) during last night’s total lunar eclipse. Credit: Bob King

Feeling a little light-headed today after staying up late to watch last night’s eclipse? Me too. But it was an event worth every minute. I outran the clouds by driving east into Wisconsin and setting up on a sandy road on a beautiful night. Temperature 71°, mostly clear and the moon doing its thing. My favorite moment happened just before it slipped fully into shadow, when that narrow, brilliant rim of sunlit moon remained like a polar cap on a red world. Fantastic.

Duluth's Matthew Moses had to deal with clouds but succeeded in capturing the first half of partial phases and totality last night. Credit: Matthew Moses
Duluth’s Matthew Moses had to deal with clouds but succeeded in capturing a wonderful sequence of partial phases up through totality last night. Credit: Matthew Moses

Totality seemed dark to me. Astronomers rate lunar brightness and color using the Danjon Scale numbered from “0”, a deep brown-red very dark eclipse to a yellow, shiny “4”. This was a “2” in my eyes. How would you rate it? (See below for the scale) During totality, the return of night was dramatic. Even though I’ve seen my fair share of eclipses, I couldn’t get over how many stars popped into view. If you looked at the moon in binoculars, they dotted the field like ornaments on a Christmas tree.

I've tried to capture the naked eye appearance in this photo of the moon taken early during totality. The lower right edge glowed a deep yellow with the remainded a rich orange-red. The upper left portion of the moon, which was closest to the center of Earth's inner umbral shadow, looked very dark. Credit: Bob King
I’ve tried to process this photo to capture the naked eye appearance in this photo of the moon shortly after the start of totality. The lower right edge glowed a deep yellow with the remainded a rich orange-red. The upper left portion of the moon, which was closest to the center of Earth’s inner umbral shadow, looked very dark. Details: 3.7-inch telescope, f/14, ISO 800, 8-second exposure. Credit: Bob King

The top or northern part of the moon passed closest to the center of Earth’s umbra — the dark, inner shadow cast by the planet — while the lower right or bottom rim passed closest to it outer edge, the reason it appeared brighter to the eye. It so happened that the darkest part of the moon coincided with a large, dark volcanic plain called Oceanus Procellarum (Ocean of Storms), enhancing the overall duskiness of that region during totality.

Telephoto shot of the moon with lots of stars. To record stars, I had to overexpose the moon, but you can still see the darkest part of the shadow like as an orange blotch over the Ocean of Storms. Credit: Bob King
Telephoto shot of the moon with lots of stars. To record stars, I had to overexpose the moon, but you can still see the darkest part of the shadow like as an orange blotch over the Ocean of Storms. Credit: Bob King

Did you have a favorite part of the eclipse? Besides the return of the starry firmament, lunar eclipses feel majestic, like the unfolding of a long, slow movement in a symphony. From quietude the music builds to a powerful crescendo before returning to a hush.

Notice anything strange about this photo? The bright part of the moon is up on top instead along the bottom as witnessed by mid-northern latitude observers. That's because the photo was taken in Sao Paulo, Brazil (latitude 23° south). I like how the moon seems to float in the frame. Credit: Willian Souza
Notice anything strange about this photo? The bright part of the moon is up on top instead along the bottom as witnessed by mid-northern latitude observers. That’s because the photo was taken in Sao Paulo, Brazil (latitude 23° south). I like how the moon seems to float in the frame. Credit: Willian Souza
A few clouds, a few stars. The moon through a 200mm lens during totality. Credit: Bob King
A few clouds, a few stars. The moon through a 200mm lens during totality. Credit: Bob King
Ah, the clouds finally caught up with me. A parting shot after totality with the moon back in partial eclipse. Credit: Bob King
Ah, the clouds finally caught up with me. A parting shot after totality with the moon back in partial eclipse. Credit: Bob King
The Danjon Scale is used to estimate the color of the totally eclipsed moon. By making your own estimate, you can contribute to atmospheric and global warming science. Credit: Alexandre Amorim
The Danjon Scale is used to estimate the color of the totally eclipsed moon. Astronomers and climatologists use that information to determine how clean or “dirty” the stratosphere is. Credit: Alexandre Amorim

Here’s the Danjon scale along with a naked-eye guide:

L=0: Very dark eclipse. Moon almost invisible, especially at mid-totality.
L=1: Dark Eclipse, gray or brownish in coloration. Details distinguishable only with difficulty.
L=2: Deep red or rust-colored eclipse. Very dark central shadow, while outer edge of umbra is relatively bright.
L=3: Brick-red eclipse. Umbral shadow usually has a bright or yellow rim.
L=4: Very bright copper-red or orange eclipse. Umbral shadow has a bluish, very bright rim.

 

10 Responses

  1. Richard Keen

    Bob, I spent most of totality driving north on a mountain road to escape a morphing and unpredictable cloud patch. But… success! After an hour of occasional patchy glimpses, I caught the last ten minutes out in the clear on a roadside at 10,000 feet elevation. At different stages I gave it a 4, 3, and a 2 on the Danjon scale. Thanks to your article on Universe Today, I’ve received 26 observations from 22 observers in 6 countries (including a Bob King in Wisconsin). The average at mid-totality is…. Two (2).
    I’m still collecting reports, but so far it appears the eclipse – predicted to be relatively dark due to the “Supermoon” that placed the moon deeper into the Earth’s shadow cone – may have been even a little bit darker.

    1. astrobob

      Richard,
      I am so glad you got to see it. Here are couple more observerations you can add:
      My own: L=2
      Dan King (LaCrosse, Wis.) L=2
      William Wiethoff (observing from Hayward, Wis.) L=1
      Willan Souza (Sao Paulo, Brazil) L= 2.5 – Naked eye – Sept. 28.093UT
      L= 2.0 – 7×50 Binoculars – Sept 28.111UT

      I had not considered that the eclipse might be darker due to the Supermoon being deeper in the shadow’s core, but it makes perfect sense. Thanks!

      1. Richard Keen

        Bob, that makes two (or more) of us happy we saw it! That completes a successful tetrad!
        Do you have exact times for those Wisconsin estimates? I’m making a graph, which I’ll send you when all the reports are in.
        There’s also some discussion about aerosols from the volcano Calbuco in Chile contributing to the darkness of the eclipse. There’s a bit on Spaceweather.com about that, but do note the cautionary note about “still crunching the numbers”.

  2. Thanks for all the info on the eclipse and your informative newsletters. Had a great view of the entire eclipse here in Boston. I also have some amateur pictures but I’m not sure how best to send them if you were interested. Anyway my question is what kind of camera do you like best for astrophotography, how long of exposures do you find work best, and what is the best way to get an accurate polar alignment for astrophotography? I know that’s a lot to answer so if you just summarize or any info at all is appreciated. Thanks.

    1. astrobob

      Hi Jason,
      If you’d like to send a photo, my e-mail is: rking@duluthnews.com
      I use a Canon 5D Mark III for my astro stuff, but other less pricier models like the Rebel might do OK, too. Exposure depends on what you want to shoot, how fast your lens is and what quality (or lack thereof) you’re willing to live with in the final image. Fast f/2.8 lenses are the best as they allow shorter exposures at lower, less “grainy” ISOs. As far as polar alignment, I only do crude alignments on the run by pointing the telescope’s polar axis at Polaris. As long as my exposures are 10 seconds or less through the telescope, it works fine. I also have a separate tracking mount that I carefully polar align using a dial-like device that allows me to accurately point the polar axis dead on the north celestial pole. I use this mount for the camera with lenses up to 300mm for exposures ranging 1-4 minutes.

  3. Troy

    I wanted to share a bit of my eclipse weather story with you. The weather had varied between clear as a bell and overcast all day on Sunday. When eclipse time approached it was cloudy. Spotty clouds did allow for some brief views during the beginning partial phases. My girlfriend was sitting on the deck and I told her I’m going to do an anti-cloud dance. Shortly after that the clouds just vanished, completely clear just before totality. A little while later my neighbor walked by and remarked at how quickly the clouds disappeared. The rest of the eclipse there were no clouds except a patch in the southeastern horizon. When I watched the news later I saw just how lucky I was: I am just east of the clear patch in the arrow, I’ll be doing anticloud dances from now on!
    http://i1305.photobucket.com/albums/s556/Pyrolon/12017630_10154161163703238_6897364094899372115_o%201_zps04my0whh.jpg

  4. Awesome thanks I’ll send a few pictures of the eclipse over. I’m using a Canon power shot that’s a few years old until I make the jump to get a new one. It only takes 15 second exposures but obviously you know even that short, especially when zoomed in, leaves decent star trails. I roughly polar aligned my telescope mount and i have a variable speed motor to track in RA but i dont quite have it down yet, so any tips help. Thanks for all the info!

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