Lunatics

When you are trying to get to the Rosette Nebula, the Moon is an annoyance.

A royal pain in the butt. The Moon is your father’s oncoming Oldsmobile refusing to dim its high beams. Worse. It is more like the high beams of an Oldsmobile driving in reverse such that you are forever blinded weeks at a time. There are not many days on either side of a new Moon suitable for flying to deep space destinations. And on top of that, clouds can manage to ruin most of those that do present themselves.

Truth be told, the Moon isn’t even what you are interested in. At all. It is old hat. Been there, done that. It is contaminated, trampled, and defaced, riddled with human detritus. An orbiting Mount Everest collecting expeditionary waste. Flags. Golf balls. Human waste. Dead space craft. The mass of junk left on the moon is estimated to be somewhere around 500,000 lbs. NASA kept a list, which it labeled as “FINAL.” Final as in 2012 final. After that NASA seems to have given up keeping track, which makes some sense, since it is no longer the sole polluter of the Moon.

Last summer, China’s Chang 6 probe landed on the far side of the Moon, destroying my long held belief that the far side was the ultimate resting place for lost socks and Bik pen tops. Just this month, two more private lander contraptions plopped down on the Moon’s surface. Firefly Aerospace’s “Blue Ghost” landed upright and began snapping selfies. It worked for 2 weeks and then went dark, shutting down as scheduled. Intuitive Machine’s “Athena” lander didn’t even manage that much. It aimed at the lunar South Pole, smacked down sideways, tipped over, drained its batteries, and died. Its only accomplishment being to initiate a new scrap heap in a southern crater.

The era of yearning for the “Man in the Moon?” Dead as the ill-fated Athena lander. The cow jumps over the Moon junk. The Moon made of Swiss cheese? Replaced by NASA JPL’s estimate of “hundreds of billions of dollars” of untapped mineral wealth. They have an infographic on how to mine it all for profit. Romance? Gone. Never again to inspire artistry from talents like Henry Mancini, Johnny Mercer, Audrey Hepburn, or Andy Williams. Forever ruined. Replaced, reduced, to bitcoins.

“That’s a little harsh, don’t you think?” asked Max.

“Mmmm.” Max comes and goes in unpredictable orbit.

“She didn’t ask for all that rubbish!”

I looked at Max. I could see he was getting a little agitated.

“Is the Moon rounding up resident asteroids and disappearing them off to a gulag on Uranus? In defiance of Natural Law? Is she mocking Mother Nature? ‘Oopsie .. too late!’ emoji emoji”

“Well no, of course not,” I offered.

“Is she threatening to impose a 25% tariff on the full moon this Tuesday? Oh, sorry, rescind that. We’ll reconsider it next month. Wait! No. It’s actually 200% as of next week. Maybe.”

“Now wait a minute, Max ...”

“Is the Moon laying off half the planets? Threatening to invade Venus? Annex the Earth? A big beautiful 51st crater?” asked Max.

“OK, OK! That’s all lunatic!”

“Exactly!” said Max. He smiled. “Stark raving mad.”

“Hey, you know what? There’s a total lunar eclipse coming up. March 14. There hasn’t been one of those since 2022. What do you say we go take a look?”

“You’re on, Maxie!”

It turned out, a Moon excursion wasn’t going to be trivial. To have a chance, we were going to need to make some modifications to our little telescope rig. Normally, when we’re traveling out to deep space objects, like Bode’s Galaxy for example, those objects are pretty faint. It takes hours of multiple long exposures, many dozens, 2 to 5 minutes long each sometimes, to capture enough light to see anything.

The moon, on the other hand, is a whole different story. Sunlight bouncing off the Moon is bright. As much as 8 f-stops brighter, in camera speak, A couple of hundred times brighter to the eye. So exposures have to be short for the Moon, something like 1/250 sec. Any longer and the result is just a big round blurry white dinner plate. Our usual astrophotography software can’t handle such short exposures, and so that meant switching back to manual settings on the camera, and triggering the exposure with a handheld remote.

The good news about a lunar eclipse is that it is leisurely. There is plenty of time to set up, frame the image, play around with exposures, and enjoy the view. Not like a solar eclipse. A solar eclipse is all tense waiting, worrying about exposures, and then 2-3 min of frantically trying to catch everything going on. Enjoying the view can be overlooked entirely if you aren’t careful.

The bad news about a lunar eclipse is that it is leisurely. Our eclipse on March 14 was going to start somewhere around 1:09 AM EDT and not be done until early birds were catching worms. It wasn’t even going to be halfway through totality until about 3 AM EDT. Max was all gung-ho, but I confess my tolerance for sleep deprivation isn’t what it used to be, back in my college days.

We set up early in the evening, made sure everything was in focus, and did some test shots. Then we rigged our little spaceship to begin tracking the Moon during the night.

For all I dismissed the Moon earlier, I realized I didn’t actually know very much about it. I know it orbits the earth every four weeks or so, out of sync with our solar orbit, thus keeping astrologers and biodynamic farmers in business. I know it is pock-marked with impact craters and covered with dusty material called "regolith." (Really fun word, "regolith!" Regolith, regolith, regolith.) And of course, I know the Moon’s gravity tugs on our oceans to create the tides, which sweep the sands of the Outer Banks. And, of course, several hundred of my missing single socks are scattered about its far side.

I learned a few other things, too. For one, the Moon is a light weight – it lacks a major iron core like the Earth. Once humanity had regolith on our boots and Moon rocks in our hands we learned a couple of other important facts too. For example, both the Earth and the Moon have similar distributions of various oxygen isotopes, which means that both must have formed in the same local environment, the same distance from the Sun. But unlike the Earth, the Moon is bone dry, almost down to the innards of its rocks, suggesting a long bake cycle in the oven.

That’s interesting; all well and good. But where did the Moon come from?

“Max? Where did the Moon come from?”

“Ah! That’s a very good question. I could tell you. But first you’d have to study centuries of Tibetan philosophy.”

“I see.” Max didn’t know either.

In fact, nobody knows for certain. The origin of the Moon is still a semi-open question for planetary astronomers. But there are several theories.

For example, one idea is that the Earth and the Moon just happened to originate independently in essentially the same spot, from the same nebular dust and rip rap, with the Moon in orbit from the gitgo. That explains the similarities between the two. But it doesn’t explain the differences. Why no core in the Moon? Why no volatiles?

Another idea is that the Earth and the Moon separated from each other by some sort of fission event. Sort of like a planetary size baker’s yeast cell budding off a daughter Moon. This model has the same problem explaining the differences in the two bodies but, even worse, there’s no evidence for the ferocious spin cycle that would be required to bleb off the Moon.

A third hypothesis is that the Moon was just minding its own business on a site seeing trip through the solar system and was captured by Earth’s gravity, forever confined to orbit our lovely Blue Dot. This model explains the differences between the Earth and the Moon, the baking and no core, but it doesn’t explain the matching oxygen isotope patterns. But the big problem with the capture hypothesis is that good old physics makes it extremely improbable. Imagine you are traveling west on I-66 in your 18-wheeler and a little VW Bug passes you headed east. You could try to capture the VW, but you’d have to choose just the right split second in which to snatch it, and you’d need tremendous arm strength to slow it down enough for capture. It ain’t likely. Don't stick your arms out of car windows.

So, currently, the predominant origin theory – the “If I had to bet” theory of most astronomers – is the Giant Impactor Theory. By this account, in the early life of the solar system a Mars-size billiard ball slammed off-center into the Earth, and blasted a few percent of Earth’s mantle out into space where it eventually coalesced into the Moon.

“That’s my favorite theory,” said Max. “Ka-Boom!!!”

“Yeah, me too, Gonzo! Ka-Boom!”

Well, there are some niggling problems still. The immense heat generated by the energy of the impact that boiled the Moon? It should have also produced some melting of Earth rocks and so far there’s no evidence for that. Moreover, Earth’s rotation should have put the ejected debris in a disk aligned along the equator, forming a Moon that more or less orbited the equator. It doesn’t. The plane of the Moon’s orbit is more in line with the Sun than it is with Earth’s equator.

“Hmph. I say it’s Ka-Boom or Bust!”

Yeah, the Giant Impactor Theory does fit most of the evidence most of the time. But our old capture model has regained a little interest recently. It becomes easier to capture a passing body if that body is really two bodies orbiting each other; a “terrestrial binary” of the Moon and her never-to-be-seen-again significant other. And there are lots of terrestrial binaries out there.

Let’s rethink that (terrible) passing automobiles analogy. What if the VW Bug was actually two VW Bugs driving in circles around each other as they also barrel past you down I-66E. As they pass, the orbiting pair might bring one of the Bugs around to travel more roughly in your direction for a wee bit. Now you can pluck it off from its partner much more easily because the momentum of the orbiting pair works to your advantage.

“Stop! You’re making me dizzy.”

“Close your eyes, Max.”

In a paper last Fall, that is exactly what Williams and Zugger calculated is physically possible for the Earth to do with a Moon-sized planet present in such a terrestrial binary. That is, the physics of our modified capture theory is no longer prohibitive. So is the Moon a captured hostage from a dance of trading-partners? Not likely? It’s always good to have a backup.

“Ka-Boom!!”

The alarm went off around 1:40 AM. Max and I trudged out to our launch site. The Moon was in partial eclipse, just as federal law, Copernicus Edition, demanded. The tracking on the scope had been pretty good, so we just had to adjust the framing a little bit to move the Moon to the center of the field. I snapped some images, bracketing exposures, and checked with Max.

“You know, this isn’t awe-inspiring, Max. It looks pretty much like any old ordinary half moon, any old month of the year.”

“But it isn’t! Think about it. This isn’t the Sun oriented to light up one half of the Moon. That would be the Moon throwing shade on itself. This is the Earth, that’s you and me, blocking the Sun and throwing shade on the Moon ourselves. Now that’s pretty cool.”

“Hmmm. That's what I was doing at the start of this story.”

We went back indoors to catch some rest.

The next time the alarm went off it was around 3 AM. This was beginning to feel a little irrational. Am I a lunatic? Max and I hiked back out to the scope and looked up. The threat of cloud cover had held off, and there it was, the full Moon totally eclipsed by the Earth. It was nowhere near as bright as before, but it glowed a deep warm red color. A color I don’t remember ever seeing before. A “Blood” Moon.

Technically? As sunlight passes through the Earth’s atmosphere, blue and green wavelengths are preferentially scattered and absorbed, leaving longer wavelength red light refracted towards the Moon, imparting that unique color, that glowing red during totality.

Visually? Well, it's pure magic.

“Wow! That’s pretty stunning, Max!”

“Told you so.”

As the eclipse ended, Max and I just stayed up to watch, take some more images, and see it slip back into its ordinary, any old half Moon, any old month phase.

The banner image at the top of this post shows an image we captured of the Blood Moon during totality, paired next to an image of its partial eclipse towards the end.

“That was a great trip, Max. Thanks. I’m sorry I said mean things about the Moon. I didn’t realize she still had so many secrets.”

“Oh, that’s alright. She doesn’t hold a grudge.”

“I guess I was just in a bad mood, doom-scrolling all the political craziness going on. It makes no sense, yet half the country thinks it’s all perfectly normal.”

“Far better to Moon-scroll,” said Max. “At least then – for the time being – you can put all the actual lunatics out of mind.”