Observing Report: January 31st’s Total Lunar Eclipse

The 2018 total lunar eclipse was witnessed by many in western North America and right across the Pacific. Here's what they saw.

Partial lunar eclipse over San Francisco

Brian Fulda captured this image on the flight deck of the USS Hornet, the aircraft carrier that picked up Apollo 11 astronauts after they became the first humans to set foot on the moon. Fulda combined two exposures for this image, one of the city and the "bloody" side of the Moon still in Earth's shadow, and another of the sunlit side of the Moon.
Brian Fulda / S&T Online Photo Gallery

A total lunar eclipse, though less dramatic than a solar eclipse, is nevertheless a sight to behold. The full Moon (total lunar eclipses by definition can only occur when the Moon is full) gradually darkens, then turns a smoldering coppery color. The total lunar eclipse of January 31, 2018, garnered a lot of attention since it was the second full Moon of the month, and the Moon had just passed perigee the day before, engendering higher-than-usual tides in coastal areas.

But the latter two points did not distract from the wonder of the phenomenon itself: Three celestial bodies are aligned in such a way that one body blocks the light from another. It’s straightforward physics, as is the fact that the surface of the Moon turns that reddish or orange-ish color due to the refraction of the light from the Sun by the Earth’s atmosphere. Witnessing a lunar eclipse is witnessing physics – and astronomy – in action.

Of those lucky enough to live in the zones of totality in continental North America, some got out of bed very early in the morning (or stayed up very late) and went outside to turn their gaze skyward. (The staff of Sky & Telescope had a less than stellar view from the East Coast, but we're looking forward to the next total lunar eclipse visible all across Northern America just a year from now, in January 2019.)

Viewers from Canada to Arizona and all the way across the Pacific to China sent in reports of the total lunar eclipse. Some simply stepped out into their backyards, while others, like Jeff Dai, shared the experience with many more: “Millions of people in Chongqing went outdoors to enjoy this beautiful celestial view.” Some enjoyed balmy weather under clear skies, while others, like Bruce McCurdy in Alberta observed the lunar eclipse through patchy cloud in temperatures down to -23°C (-9°F) with a wind chill of -34°C (-29°F).

Sky & Telescope’s Contributing Editor Alan Whitman, from his prime viewing spot in British Columbia, noted that, “This was another very bright orange total lunar eclipse. Even at mid-eclipse the Moon was about three magnitudes brighter than Pollux.”

Viewers in California had a different experience. Hiram in Santa Cruz observed what “… looked like a very dark eclipse,” and Robert Garfinkle writes, “It was a very dark reddish total lunar eclipse here in the San Francisco Bay Area.”

How can the same phenomenon be described as both “bright” and “dark” at the same time by observers on the western coast? Terry Moseley, replying to comments on the Solar Eclipse Mailing List, explains, “The appearance could depend on the amount of light pollution. In a brightly lit city, a total lunar eclipse could appear quite dark, even if it was bright on the Danjon scale. But in a dark sky, it might appear relatively bright.”

Totally eclipse Moon as seen from Pune, India.
Amit V. Purandare / S&T Online Photo Gallery

Apart from notes on brightness, what other details did viewers observe?

Alan Whitman saw “… a bright yellow-white rim on the Moon’s southern limb although it became very thin at mid-totality,” and “…the northern limb, deepest into the umbra, was orange, not red.”

In the San Francisco Bay Area, Robert Garfinkle noted that “… during totality, the western half (Grimaldi side) disappeared from my view,” while Alan Whitman states that “… Grimaldi was prominent within the brighter edge of the umbra…” He goes on to say that “… the bright rays around Copernicus, Kepler, and Aristarchus were all prominent, but not the craters themselves.”

To give you an idea of the difference in illumination between pre-eclipse moonlight and during the eclipse, Robert Garfinkle writes, “Before the eclipse began, my backyard was so bright it was as if I had some low-wattage lights on. By the time the umbral portion of the eclipse had covered only part of Oceanus Procellarum the ‘lights’ went out and my backyard was dark like on a new Moon night.”

Do share your own experiences with us in the Comments section below and share your photos with us in our Online Photo Gallery!

13 thoughts on “Observing Report: January 31st’s Total Lunar Eclipse

  1. Graham-Wolf

    Hi Diana,

    Sadly… the Total Lunar Eclipse was NOT seen from Dunedin, NZ.
    I was officially to get the full 76 minutes of totality, but got zip instead… of the entire event.

    Five hours before it was due to start, there was a huge forest fire just 5km to the West. The pyro-cumulus from that, added to the sudden overcast skies within 20 minutes, then a few minutes before the actual Eclipse start, tropical cyclone FEHI came through, and trashed my region for the next two days. Over 800 evacuated, but at 142m elevation, I was not one of them!

    High winds, floods, spring tides, raging southerly fronts, and an official state of emergency, which only lifted just a few hours ago. Southern part of Dunedin is still ominously sand-bagged. The abnormal spring tides only compounded the situation of the cloud-bursts…. yesterday morning, we got some 20 – 22mm of rain in just 40 minutes, and some 4 1/2 inches just yesterday morning. We had been continuously sweltering in 30+ Celsius temperatures these last two weeks or so, so the ground was already baked dry.

    As Radio Ham ZL2-CHAR (Charlotte Dawson Memorial Station) I was on 48 hour standby on DN-690 2m FM Repeater for any emergency radio traffic…. AREC were called to Central Police Station for a pre-brief. No-one was harmed.

    Murphy has “nailed” me before with total lunar eclipses.
    Just wasn’t meant to be my night.
    Hope many others fared much better than me.
    Looking forward to seeing their reports and pics, as South Dunedin now mops up the tropical cyclone mess.At least we didn’t get cyclone Katrina, and we’re not New Orleans, but I reckon we Kiwis still got a good whiff of what they got!

    Again, no-one was harmed down here in the antipodes.
    No Eclipse, no data, and trying rather hard not to feel personally angry about it.
    Scattered showers as I type this, right now…

    Graham W. Wolf
    46 South, Dunedin, NZ

    1. RussRuss

      Thanks for the report, Graham. It’s always good to hear about events affecting astronomers in other parts of the world. I’m sorry it was such a calamity for your area, and hope for the best for those impacted. I’m sure you are aware there will be other eclipses and events you’ll be able to enjoy. Alas, for this one you’ll need to be satisfied with reports from elsewhere. Thanks also for the report about events involving AREC, as I too am in involved in the same. We call it ARES in the US.

      As for my experience with the present eclipse, I would gladly trade that for a good view of the Magellanic Clouds.

    2. Diana Hannikainen Post author

      Wow, sounds like you had a pretty rough time… good to hear no one was harmed. Here’s hoping for better luck for you next time. – diana

  2. StarChaser55StarChaser55

    “…But in a dark sky, it might appear relatively bright.”
    We had very dark skies for the eclipse here at our cabin in the Davis Mountains of West Texas (just four miles from McDonald Observatory), yet to us it appeared very dark; probably due to the low lunar elevation: light from the moon had to traverse the equivalent of 5 air masses at the start of totality, increasing to around 8 air masses by the time the moon disappeared behind a ridge. The color changed from a deep orange to dark red. It was an awesome sight, well worth getting up early for!

  3. Mhanafin

    We got very, very lucky in Vancouver BC…after days and days of rain, partial phase started (3:48 am PT) in partial clouds, but at 4:05 the clouds moved out and we had mostly clear skies through totality. The moon was quite low in second partial phase so I packed it in. Viewed in binoculars–and naked eye–I observed above average brightness (L= 3.5?) Orange-ish…not red, but with bright white/yellow rim near bottom edge of umbral shadow (not blue). Great eclipse…I’ve seen approx. 20 and this was in my top 3 for brightness and visual beauty.

  4. Anthony BarreiroAnthony Barreiro

    I watched the eclipse from San Francisco, California. I was on the western slope of Bernal Hill looking west toward Twin Peaks. The top of the hill shielded me from the worst of the light pollution emanating from downtown, and the sky toward the west was relatively dark. During totality we could see stars down to fifth magnitude, and a couple of people walked right into me without seeing me.

    I watched the eclipse both naked eye and through 10×42 binoculars. To my naked eye, during mid-eclipse the Moon looked dark grey toward the center of the Earth’s umbra, and slightly, deeply red toward the edge of the umbra. Through binoculars the Moon looked brighter and redder. I am not an expert, but I would call this eclipse L1 on the Danjon scale. A member of my astronomy club in Petaluma, 40 miles north of here, took a photo of the partially eclipsed Moon that looks brighter red than I saw, with a subtle purplish edge to the Earth’s umbra, which I didn’t see at all.

    My understanding is that lunar eclipse brightness / darkness judgments should be made without optical aid. I wonder how much of the discrepancy between different reports could be attributed to differences in equipment, especially aperture and magnification.

    Anyway, I guess that color perception is fundamentally in the eye and mind of the beholder.

  5. Graham-Wolf

    Absolutely correct, Anthony!

    Danjon himself started his system using naked eye estimates.
    Sure, it’s personally subjective…. one person’s Danjon 2.8, is another’s 3.5!

    The important thing here is to clearly describe your methodology, so that your peers out there, can (hopefully) convert to a standard reading. They know what works and what doesn’t. Fred Espenak (Dr Eclipse) has useful websites out there, and I proudly rate Fred as one of the world’s foremost experts on viewing eclipses… particularly the solar ones. His scientific cred is absolutely huge, and he bends over backwards to help others!

    And let’s not forget the great folks at Sky and Telescope… their useful guides and “how-to’s” make life a lot easier out there… thanks folks! I’ve been doing these for over 5 decades, and I STILL don’t know it all…. reckon I’ve barely scratched the surface.

    Graham W. Wolf at 46 South, Dunedin, NZ.

    Civil Emergency down here lifted a few hours ago. Full Moon rose over the city in clear skies about 4 hours before dawn today. The huge bush fire 6 rs before Cyclone Fehi on the outskirts, is still smouldering and stinking the city, three days later…. but we;’re all safe. Murphy sure got me good.

  6. Graham-Wolf

    Great hi-speed vid of the Eclipse.
    Just had a view of it… thanks for the hypertxt link……
    Well done, Melbourne.
    Go the mighty ANZACs!

    Graham W. Wolf
    46 South, Dunedin, NZ

  7. RussRuss

    I wanted to add my impressions of the 2018 eclipse experience. While I’ve seen dozens of eclipses over the years, this one seemed to be colored like 90% percent of them are – deep rusty red in the darkest part of the shadow, with a lighter colored rim. Compared to the eclipse in October 2014 eclipse, which had a bluish outer rim, the 2018 eclipse had a more yellowish color to the outer reaches of the shadow.

    On one notable eclipse from the 1960s, the Moon was so dark that it was invisible to the unaided eye. Its location was only apparent by the absence of stars in Gemini where it was situated. It took binoculars to actually see the eclipsed lunar disc. Only the vaguest warm tones could be discerned – mostly just charcoal black. The view from the lunar surface at that time would have been strange – no sunset colors surrounding the Earthly disc. But the 2018 eclipse was quite bright. Best views of the Milky Way were had when the Moon wasn’t in my field of view.

    So it was notable in the 2018 experience how dark the sky became at mid-eclipse. The Milky Way was visible along the horizon from the northwest in Auriga through Cassiopeiae in the north on to Cygnus in the northeast. Not bad for the night of a full Moon! It helped that the marine fog layer below my 2600 foot elevation darkened the few light domes of the distant cities. Most noticeable was Eugene, Oregon – some 75 miles distant. But none of these light domes were enough to appreciably impact the beautiful Milky Way.

    This eclipse is another notable experience to remember. While it was cold, it didn’t snow like it did just before the April 2015 eclipse. After dropping around 1/2 inch of snow at my 3600 foot location, it cleared for that eclipse. It was actually colder in 2018, with frost on much of my photographic equipment and the ground. Still this eclipse is one I’ll long remember.

  8. Fred-Espenak

    This is the 30th total lunar eclipse I have observed (or attempted to observe since 9 were clouded out).

    About 20 minutes into the total phase, I used binoculars (reversed) to estimate the integrated brightness of the Moon. My estimate is magnitude -2 (or even -2.5) , and with a Danjon value of about 3.5. This makes it a relatively bright total lunar eclipse.

    I note that when the partial phase was at about 50%, I could easily make out the entire half of the Moon already embedded in the umbra. This is consistent with a bright total eclipse.

    A highlight for me was to watch the tottaly eclipsed Moon set behind the Chiricahua Mountains (See the APOD photo for Feb. 1, 2018).

    I viewed the eclipse from a very dark location in southern Arizona free from light pollution.

  9. Diana Hannikainen Post author

    Hello all,

    Thank you all so very much for your informative and detailed observing reports and comments! I very much enjoyed reading them. And next time round I’ll be a bit more on the ball with getting back to you! Thanks again, – diana

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