The asteroid 469219 Kamoʻoalewa isn’t exactly Earth’s second moon. But it’s been circling our world for centuries: and near Earth’s orbit for much longer.
Now scientists say they’ve traced the asteroid back to Giordano Bruno crater on the Moon.
I’ll be taking a look at what I could find of their research, Earth’s moons, and asteroids whose orbits keep them near Earth. Then I’ll talk about one of the more colorful personalities of the Renaissance.
Asteroid Kamoʻoalewa, Giordano Bruno Crater: Origins & Orbits
469219 Kamoʻoalewa is a small asteroid that’s circling, but not orbiting, Earth. If it came from Earth’s moon, which seems likely, it’s probably debris from the Giordano Bruno impact event.
Before getting into Kamoʻoalewa’s origins, a quick (for me) look at Earth’s neighborhood.
Earth has only one moon. Make that only one large moon that isn’t artificial, and that’s been orbiting our planet for a very long time.
Like so much else, it’s complicated.
Earth’s moon — it’s actually more like ‘the other part of the Earth-Moon double planet’ — And that’s another topic. Anyway, the Moon has been orbiting Earth, or sharing Earth’s orbit, good grief: point is, it’s been around Earth for billions of years.
Folks have claimed that they found a second moon for Earth at least since 1846.
But until very recently, other astronomers couldn’t find Petit’s, Waltemath’s, or other second natural satellites. That changed, maybe in the early 21st century.1
I haven’t verified when the first ‘second moon’ claim was backed up by other researchers finding the same thing.
Dust, Asteroids, Astrodynamics, Temporary Moons, and Lagrange points
There’s a mess of small Solar System objects with orbits near Earth’s, but they’re not usually orbiting our world.
On the other hand, sometimes they become temporary moons.
2006 RH120, for example, orbited Earth from July 2006 to July 2007. 2020 CD3 was a moon from somewhere around roughly 2016 or 2017 to May 7, 2020.
Earth’s Moon isn’t going anywhere, not soon at any rate, since it’s well inside Earth’s (astrodynamic) sphere of influence. That’s an oblate-spheroid-shaped volume of space where Earth outvotes other gravitational influences.
Oh, boy. Geek-speak and anthropomorphism. An oblate spheroid is a squashed sphere, sort of like a loaf of pumpernickel.
The two main mathematical models for an astrodynamic sphere of influence are called the Hill sphere and Laplace sphere.
Earth’s gravity isn’t the only thing affecting stuff inside these spheres.
There’s radiation pressure from the sun, for one thing; and the gravitational influence of everything else for another.
Like I said, complicated. Very complicated.
Long before 2006 RH120 and 2020 CD3 were spotted, Kazimierz Kordylewski said that he’d detected two roughly banana-shaped dust clouds, centered on the Moon’s L4 and L5 Lagrange points.
The L4 and L5 Lagrange points are the spots in a planet or moon’s orbit sixty degrees ahead and behind the object where gravity of the two larger bodies balance out.
Kordylewski died in 1981.
Then, in October of 2018, the Royal Astronomical Society confirmed that the Kordylewski clouds are real.2
One reason I like living in our current “now” is that international cooperation, among scientists at any rate, isn’t as grudging — or difficult — as it’s occasionally been.
When Circling Isn’t Orbiting: Quasi-Satellites
(“Asteroid 2016 HO3 — Earth’s Constant Companion”, NASA Jet Propulsion Laboratory (June 23, 2016))
I think that video does a better job than I could, of explaining how 469219 Kamoʻoalewa is circling Earth, but not orbiting our planet.
About the video’s title, “Asteroid 2016 HO3…”, 469219 Kamoʻoalewa had the provisional designation 2016 HO3 when NASA posted that video: June 23, 2016.
I talked about astronomical names and designations back in 2021. There’s a link near the end of this post.
Anyway, 469219 Kamoʻoalewa is a quasi-satellite of Earth. It’s circling our planet at the moment, but it’s outside Earth’s astrodynamic sphere of influence.
469219 Kamoʻoalewa stays close to Earth because it’s in a co-orbital configuration: a 1:1 orbital resonance with Earth. Its year is the same length as Earth’s.
Objects with a particular sort of orbital resonance that keeps them close to a planet, but that stay outside the planet’s sphere of influence, are called quasi-satellites.3
Don’t bother trying to remember that stuff: there won’t, happily, be a test on this.
In This Week’s News: 469219 Kamoʻoalewa and a Lunar Crater
“This Crater Could Be Where Earth’s ‘Second Moon’ Broke Off The First One“
Michelle Starr, ScienceAlert (April 22, 2024)“You may never be able to go home again, as the old proverb asserts, but for a chunk of rock sharing Earth’s orbit around the Sun, you might at long last know where it is.
“The provenance of asteroid Kamo’oalewa, discovered in 2016, is something of a mystery, but astronomers believe it may be a chunk of the Moon. A new analysis has even identified the crater from which it may have been gouged.
“Using numerical simulations, a team led by astronomer Yifei Jiao of Tsinghua University in China has determined the properties of the crater most likely have to produced the asteroid, and found a real one that matches those properties: the Giordano Bruno crater on the far side of the Moon.
“‘We have explored the processes for impact-induced lunar fragments migrating into Earth co-orbital space and presented support for Kamo’oalewa’s possible origin from the formation of the Giordano Bruno crater a few million years ago,’ the researchers write in their paper.
“‘This would directly link a specific asteroid in space to its source crater on the Moon and suggests the existence of more small asteroids composed of lunar material yet to be discovered in near-Earth space.’…”
That’s what got me started on this week’s post.
This year’s study of 469219 Kamoʻoalewa wasn’t the first that discussed why the asteroid probably started as a piece of the Moon’s crust. I’m pretty sure it won’t be the last.
The way 469219 Kamoʻoalewa reflects light very strongly suggests that it spins around once every 28 minutes, give or take a bit.
Assuming that 469219 Kamoʻoalewa is an S-type asteroid, again based on how it reflects light, it’s very roughly 40 to 100 meters across: 130 to 330 feet.
That’s not huge, but since 469219 Kamoʻoalewa is spinning so (comparatively) fast, it’s almost certainly a solid piece of rock: not a rubble pile.
Yifei Jiao’s team probably built on research published in 2021 that looked at orbital mechanics and the odds of Lunar impacts in various places sending rocks into resonant orbits.
- “Lunar ejecta origin of near-Earth asteroid Kamo‘oalewa is compatible with rare orbital pathways“
Jose Daniel Castro-Cisneros, Renu Malhotra, Aaron J. Rosengren; Springer Nature (2021) via arXiv
I also found discussions of a possible connection between 12th century monks and Giordano Bruno crater on the Moon. Possible, but not probable.4
I’d prefer getting a look at the 2024 Kamoʻoalewa research paper, but ran into the same problem as I did last week. I was either looking in the wrong place, or lack the proper credentials: maybe there are other explanations, too.
So my guess, that the 2024 paper builds on 2021 research by Castro-Cisneros, Malhotra, and Rosengren — will remain just that: a guess.
Horseshoe Orbits and Naming Kamoʻoalewa
Although I didn’t find the latest Kamoʻoalewa paper — actually, I did find it. I know where it is, but I don’t have access to it. And I’m wandering off-topic.
Anyway, 2024 Kamoʻoalewa is a quasi-satellite of Earth, circling our planet, but in its own orbit around the Sun. That’s a temporary situation.
Using math that I’ve read about but can’t actually do, scientists have worked out 2024 Kamoʻoalewa’s orbit: from the year 1600 to 2500.
Details vary, depending on which models they’re using.
But there’s pretty good agreement that 2024 Kamoʻoalewa was in a horseshoe orbit around the sun until about a century back, and will transition back into a horseshoe orbit a few centuries from now.
Horseshoe orbits are another sort of co-orbital configuration. Except that instead of being in a 1:1 orbital resonance with a planet that keeps the object circling the planet, an object in a horseshoe orbit circles the planet’s orbit.
Instead of circling a fixed point on the planet’s orbit, the object drifts back and forth along the orbit. The shape reminds me of patterns a Spirograph® makes, only in three dimensions. Four, if you include time.
Let’s see, what else?
2024 Kamoʻoalewa was spotted by the University of Hawaii’s Institute for Astronomy’s Pan-STARRS asteroid survey telescope. Pan-STARRS gets funding from NASA’s Planetary Defense Coordination Office.
The name Kamoʻoalewa sounds Hawaiian because it is: ka ‘the’, moʻo ‘fragment’, a ‘of’, lewa ‘to oscillate’. Folks at the A Hua He Inoa, ʻImiloa Astronomy Center of Hawaiʻi came up with the name, and it’s been official since April 6, 2019.5
(Almost) finally: that possible-but-not-probable connection between 12th century monks and the Giordano Bruno crater.
Gervase of Canterbury and a Monkish Mystery
Gervase of Canterbury is one of the monks who buried St. Thomas of Canterbury, after Thomas didn’t live down to his king’s expectations.
Gervase of Canterbury is also known as an English chronicler.
In 1976, a geologist said that this excerpt from Gervase of Canterbury’s writings recorded an observation of the Giordano Bruno crater impact event:
“…[On the evening of June 18, 1178] after sunset when the moon had first become visible a marvelous phenomenon was witnessed by some five or more men…Now there was a bright new moon…its horns were tilted toward the east; and suddenly the upper horn split in two. From the midpoint of the division a flaming torch sprang up, spewing out, over a considerable distance, fire, hot coals, and sparks. Meanwhile the body of the moon which was below writhed, as it were, in anxiety…the moon throbbed like a wounded snake. Afterwards it resumed its proper state. This phenomenon was repeated a dozen times or more, the flame assuming various twisting shapes at random…Then after these transformations the moon from horn to horn…took on a blackish appearance. The present writer was given this report by men who saw it with their own eyes, and are prepared to stake their honour on an oath that they have made no addition or falsification in the above narrative….”
(Gervase of Canterbury (ca. 1200) via Melanie Melton, Planetary Society)
The last I checked, there’s no proof that the five monks actually saw a lunar impact; and pretty good reasons for thinking that they didn’t.
For one thing, the Giordano Bruno crater is probably between one and 10 million years old, maybe older. For another, the odds that an impact as big as the one that made that crater happened in the last thousand years is — minimal.
Besides, an impact like that would have thrown something like 10,000,000 tons of rock into the Lunar sky.
Some of that would have escaped the Moon’s gravity and fallen toward Earth. Nobody, anywhere, wrote about an epic meteor shower around that time.
Maybe the monks just happened to be in the right spot to see a meteor flame out in the English sky, between them and the Moon.
Monks, a meteor, and the Moon being lined up like that is a low-probability event. But so is a Lunar impact happening just then. Given that the Canterbury light show was probably local, odds are that the monks did not witness a Lunar impact.
I was mildly surprised to see no learned composition, asserting that the monks couldn’t have seen a Lunar impact: because both Gervase and the witnesses were monks. And that monks are religious people who, of course, hate science.
The closest I found to that attitude was what I think was a lighthearted reference to Chaucer’s Canterbury Tales.6
“…Gervase’s report must either be an impact event with a wrong date or a nonimpact event. In either case, the connection between the Canterbury event and the Canterbury Swarm must be a Canterbury Tale.”
(“Lunar Event of 1178A.D. — a Canterbury tale?“, B. E. Schaefer, P. M. Bagnall; Journal of the British Astronomical Association (October 1990))
Giordano Bruno Died For Your Sins??
“The fools of the world have been those who have established religions, ceremonies, laws, faith, rule of life….”
(“Cabal of the Cheval Pegasus”, Giordano Bruno (1585) via Wikiquote)“All things are in the Universe, and the universe is in all things: we in it, and it in us; in this way everything concurs in a perfect unity.”
“The Universe is one, infinite, immobile. … It is not generated, because there is no other being it could desire or hope for, since it comprises all being. It does not grow corrupt. because there is nothing else into which it could change, given that it is itself all things. It cannot diminish or grow, since it is infinite.”
(“Cause, Principle, and Unity”, Giordano Bruno (1584) via Wikiquote) [emphasis mine]
Giordano Bruno was a philosopher, poet, cosmological theorist, and (Western) esotericist. Stanford Encyclopedia of Philosophy says he was “one of the most adventurous thinkers of the Renaissance”.
The self-described best and brightest of the 19th and early 20th centuries said Giordano Bruno was a martyr for science: because he was tried by the Roman Inquisition, and burned at the stake in the Campo de’ Fiori.
It’s true that some of his opinions turned out to be (mostly) right. And that his opinions got him in trouble with the powers that be.
He also had self-esteem above and beyond the call of reason.
By the time I was getting interested in science, Giordano Bruno was still recognized as a Glorious Martyr for the Cause.
But by then, the best and brightest were focusing more on Galileo Galilei as the Champion of Truth and Science.
Galileo, heroically standing firm against the Forces of Oppression, whose weapons were Superstition and Ignorance. It made a compelling story.
I’m not sure why focus shifted to Galileo. Maybe it was because he had actually done significant scientific research.
Giordano Bruno was more of a philosopher. He’d started out as a Dominican friar, then (probably) became a Calvinist. Both the Lutherans and the Calvinist Council excommunicated Bruno. Eventually he told the Roman Inquisition that they were wrong and he was right.
In 1600, Giordano Bruno was burned at the stake in Rome’s Campo de’ Fiori.
These days, that’d be like someone being electrocuted in Washington D.C.’s National Mall. Or maybe New York City’s Times Square.
Although some folks still regard Giordano Bruno as a martyr for science, I gather that most historians have gotten around to checking their records.
His ideas about cosmology weren’t conventional. But it was Bruno’s imaginative and fervent rebranding of nifty old ideas that got him in trouble.
The Bruno spin metempsychosis and panpsychism, for example, was new. The ideas themselves had been around at least since the Axial age.7
Attitudes and Assumptions: Giordano Bruno and Nicholas of Cusa
Giordano Bruno got some things right. Stars are other suns, and planets orbit a great many of them.
Over the last few decades, we’ve made observations which strongly suggest that this universe is infinite. Or that it isn’t. There’s a debate in progress, regarding that point.
The physical universe we’re in may be the only one. Or maybe we live in one of an unknown number of ‘universes’. That’s another debate in progress.
A century before Giordano Bruno left a trail of repackaged beliefs — and scorch marks in the Campo de’ Fiori — Nicholas of Cusa had said that Earth isn’t the center of the universe, and that there might be other worlds — — —
But Nicholas of Cusa was a Catholic cardinal. And everybody knows what they’re like.
I don’t know what went wrong in the centuries between Saints Hidegard of Bingen, Albertus Magnus, Thomas Aquinas — and Europe’s 16th-century meltdown.
The 11th through 13th centuries were no picnic, either: I’ve talked about that before.
Looking back at the Giordano Bruno and Galileo SNAFUs with 20-20 hindsight, I see some wisdom in Galileo’s permanent time out. I can even see why his books were banned, and why Giordano Bruno was executed.
That doesn’t mean I think either was a good idea. Censorship and the traditional right of folks in charge to kill their subjects are topics for another time.
Besides, I’ve talked about it before.8
Censorship, Dante, and Me
No, I won’t let it go at that.
I’m no great fan of censorship.
That’s partly, I suspect, because I’m an American who grew up in the 1960s.
I wasn’t on the same page as The Establishment then. Now that the folks in charge have different quirks and slogans: I’m still not on the same page.
I’d be even less enthusiastic about the powers that be, if my homeland hadn’t somehow held on to the curious notion that folks shouldn’t be punished for expressing unsanctioned opinions.
And that’s yet another topic or two, for another time.
I’m also aware that, although the folks in charge may be highly proficient in hanging on to their fancy titles and big offices, they don’t necessarily have a clue about anything else.
Like Dante being accused of heresy: based on lines 103 through 108 of “The Divine Comedy”, Inferno.
Seems that Dante Alighieri’s imagery, illustrating the union of body and soul — looked like a heretical denial of the Resurrection. To some of his poetically-challenged contemporaries, at any rate.
“…The Suicides willed the death of the flesh, but they cannot be rid of it: their eternity is an eternity of that death. (The absurd charge of heretically denying the resurrection of the body was brought against Dante on the strength of these lines, but only by those to whom the language of poetic imagery is a sealed book.)”
(Dorothy L. Sayers’ footnote to “The Divine Comedy,” Inferno, Canto XIII, line 107; “The Divine Comedy 1 Hell,” Dante Alighieri, Translation by Dorothy L. Sayers (1949); Penguin Classics reprint) [emphasis mine]
I’ve talked about that before, too.9
Finally, although I’m glad that my access frustrations are mainly limited to paywalls and unnecessarily rigid members-only information services — I do look for “nihil obstat” (“nothing hinders”) in publications that deal with matters of faith and morals.
If I find something that doesn’t seem to make sense in an approved document: odds are that I’m missing something. And that’s — you guessed it — yet again another topic.
As for whether God’s universe fits this, that, or the other cosmological model?
I figure part of our job is learning how God’s creation works: accepting what we’ve learned, and to keep learning.
“Our God is in heaven and does whatever he wills.”
(Psalms 115:3)
More, or less, of the same:
- “Medieval Monkish Medicine: Scientific Before Science was a Thing“
(November 14, 2023) - “India: Fourth on the Moon, First near Lunar South Pole“
(August 26, 2023) - “DART Mission, Successful Planetary Defense Test; What’s Next“
(October 1, 2022) - “A Star by Any Other Name, and a Galilean Interlude“
(November 13, 2021) - “Earth’s Moon: Heat, Stir – – –“
(November 5, 2018)
1 Asteroids, moons, and orbits:
- Wikipedia
2 More than you need, or maybe want, to know about:
- Wikipedia
- 2006 RH120
- 2020 CD3
- 2023 FW13 (first spotted in March, 2023; circling Earth in a 1:1 resonant orbit)
- Aten asteroid (one of a group of asteroids that get close to Earth)
- Earth trojan (an asteroid orbiting in the Earty-Sun L4 or L5 points)
- Gravity
- Kazimierz Kordylewski
- Kordylewski cloud
- Lagrange point
- List of Earth-crossing asteroids (orbits cross, but don’t necessarily intersect, Earth’s)
- List of minor-planet groups
- List of objects at Lagrange points
- Near-Earth object
- Orbital mechanics (AKA astrodynamics)
- Orbital resonance
- Quasi-satellite
- Radiation pressure
- Sphere of influence (astrodynamics)
- Spheroid
- Temporary satellite
- How we got to a point where Sirius is also called Aschere, Canicula, Al Shira, Mrgavyadha and Lubdhaka, α Canis Majoris (α CMa), 9 Canis Majoris (9 CMa), HD 48915, HR 2491, BD-16°1591, GJ 244, ADS 5423, and HIP 32349
- Wikipedia
- Co-orbital configuration (a particular sort of orbital resonance)
- Orbital resonance
- Provisional designation in astronomy
- Quasi-satellite
- Wikipedia
- “Asteroid Kamo‘oalewa’s journey from the lunar Giordano Bruno crater to Earth 1:1 resonance“
Yifei Jiao, Bin Cheng, Yukun Huang, E. Asphaug, Brett Gladman, Renu Malhotra, Patrick Michel, Yang Yu, Hexi Baoyin; abstract and figures; Nature Astronomy (April 2024) via ResearchGate - “The possible origin of the Near-Earth Asteroid Kamo’oalewa (469219) as Lunar ejecta“
Jose Castro, Renu Malhotra, Aaron Rosengren; 55th Annual Meeting of the Division for Planetary Sciences, id. 321.08. Bulletin of the American Astronomical Society, Vol. 55, No. 8 e-id 2023n8i321p08 (October 2023) - “Asteroid Bennu’s Surprising Surface Revealed by NASA Spacecraft“
“Near-Earth asteroid Bennu is a rubble pile of rocks and boulders….”
NASA’s Goddard Space Flight Center (July 7, 2022) - “Lunar ejecta origin of near-Earth asteroid Kamo‘oalewa is compatible with rare orbital pathways“
Jose Daniel Castro-Cisneros, Renu Malhotra, Aaron J. Rosengren; Springer Nature (2021) via arXiv - “Giordano Bruno, The Big Picture“
Mark Robinson; LROC & LRO (June 26, 2012) - “How Young is the Lunar Crater Giordano Bruno?“
Linda M. V. Martel, Hawai‘i Institute of Geophysics and Planetology (2010) - “The Night the Moon Split in Two — What really happened one night in June, 1178.“
Melanie Melton, Planetary Society (Paul Withers, PhD; Boston University) (April 20, 2001) - “Lunar Event of 1178A.D. — a Canterbury tale“
B. E. Schaefer, P. M. Bagnall; Journal of the British Astronomical Association, Vol.100, NO. 5 (October 1990) - Gervase of Canterbury
Catholic Encyclopedia (1913) via Wikisource
5 Kamoʻoalewa lore and science:
- Wikipedia
- 469219 Kamoʻoalewa (AKA 2016 HO3)
- Co-orbital configuration (a particular sort of orbital resonance)
- Horseshoe orbit
- Meanings of minor planet names: 469001-470000
- Planetary Defense Coordination Office
- Quasi-satellite
- Pan-STARRS
- Spirograph
- “Lunar ejecta origin of near-Earth asteroid Kamo‘oalewa is compatible with rare orbital pathways“
Jose Daniel Castro-Cisneros, Renu Malhotra, Aaron J. Rosengren; Springer Nature (2021) via arXiv - “A quasi-satellite of Earth, named Kamoʻoalewa, might actually be a chip off our Moon.“
Jeff Hecht, Sky & Telescope (November 16, 2021) - “Asteroid (469219) 2016 HO3, the smallest and closest Earth quasi-satellite“
C. de la Fuente Marcos, R. de la Fuente Marcos; Monthly Notices of the Royal Astronomical Society (August 8, 2016)
6 A medieval monk moon mystery:
- Wikipedia
- “How Young is the Lunar Crater Giordano Bruno?“
Linda M. V. Martel, Hawai‘i Institute of Geophysics and Planetology (2010) - “The Night the Moon Split in Two — What really happened one night in June, 1178.“
Melanie Melton, Planetary Society (Paul Withers, PhD; Boston University) (April 20, 2001) - “Lunar Event of 1178A.D. — a Canterbury tale?“
B. E. Schaefer, P. M. Bagnall; Journal of the British Astronomical Association, Vol.100, NO. 5 (October 1990) - Gervase of Canterbury
Catholic Encyclopedia (1913) via Wikisource
“Giordano Bruno (1548–1600) was one of the most adventurous thinkers of the Renaissance. Supremely confident in his intellectual abilities, he ridiculed Aristotelianism, especially its contemporary adherents. Copernicus’s heliocentric theory provided a starting point for his exposition of what he called a ‘new philosophy’. … The universe was infinite, animate and populated by numberless solar systems. It was also eternal. As such, it exhibited all possibilities at any given moment, and all parts of it assumed all possibilities over time, thereby constituting a cognizable manifestation of a timeless and absolute principle, God. In keeping with these ideas, Bruno proposed versions of metempsychosis, polygenism, panpsychism and, renouncing Christian emphases on human imperfection, advocated a morality that exhorted individuals to perfect their intellectual powers.”
(Giordano Bruno, Stanford Encyclopedia of Philosophy) [emphasis mine]
- Wikipedia
- Axial Age
- Custer Died for Your Sins (published 1969, during an era of long-overdue reforms)
- Dominican order
- Galileo Galilei
- Giordano Bruno
- Metaphysics
- National Mall
- Orphism (religion)
- Panpsychism (the idea that ‘the mind is a fundamental feature of the world which exists throughout the universe’)
- Plato
- Polygenism (the idea that different human ‘races’ have different origins)
- Thales of Miletus
- Times Square
- Western esotericism
- metempsychosis “the passing of the soul at death into another body either human or animal”
Merriam-Webster Dictionary - MOON — Giordano Bruno
Gazateer of Planetary Nomenclature, USGS - Giordano Bruno
Stanford Encyclopedia of Philosophy (First published Wed May 30, 2018; substantive revision Tue Mar 12, 2024) - Giordano Bruno
Catholic Encyclopedia (1908) via NewAdvent.org
8 Three Saints, a little philosophy, and history:
- Wikipedia
- ‘We’ve always done it this way’, my view
- “Capital Punishment: It Could be Worse” (February 3, 2024)
- “Free to Agree With Me: Cancel Culture and Freedom of Expression” (November 18, 2023)
9 Censorship, freedom of expression, poetry, and me:
- Wikipedia
- Making sense is an option
