Welcome back to the Abstract!
Whatever else you think of this past week, it sure served up some ridiculously good science. I’m talking about a real boffin buffet, with all the fixings. There were studies about trees spying on illegal mines. Or, an eerie rhino graveyard buried in ash 12 million years ago. Or, the first baby born from a remote and fully automated sperm injection. And those were all ones I had to regretfully leave in drafts, on account of the sheer scientific bounty.
For starters, there was a whole study this week predicated on what mariners have been writing in ship logs over the past 400 years. I’d have to turn myself into the authorities if I didn’t highlight it, for it would indeed be a crime.
Next, the universe is acting up again and refuses to conform to our meticulously curated models. I would tell the universe to go to its room, but it is the room. Then, crows continue to prove that “bird brain” is a compliment, actually. Last, take a few seconds for Uranus. No, I mean, literally.
Do You Take Milk in Your Sea?
It has happened again: A study has turned to historical documents to make scientific conclusions. As I’ve mentioned previously, this is one of the absolute best flavors of research because we all get treated to a bunch of old-timey accounts of weird phenomena—in this case, the entrancing spectacle of “milky seas.”
Milky seas are produced by bioluminescent bacteria that can transform the nighttime ocean into a glowing white veneer. For centuries, seafarers have marvelled at the eerie beauty of these surreal displays, which sometimes last for months and can cover areas of 100,000 square kilometers (about the size of Iceland).
“Milky seas are a rare, historically fabled form of marine bioluminescence” that is characterized by their steady, non-flashing, eponymous white glow,” said Justin Hudson and Steven Miller of Colorado State University. “Eyewitnesses have compared the experience of sailing through a milky sea to a snowy plain at night, the “Twilight Zone,” and even the biblical apocalypse.”
“Despite centuries of scientific research into milky seas very little is known about the physical and biogeochemical processes which govern their formation, longevity, and size,” the team continued. “Scientific inquiry into milky seas has historically been held back due to the paucity of data, and the remote, ephemeral nature of the phenomenon.”
You know what that means—time to hit the stacks! Hudson and Miller compiled a trove of eyewitness accounts, spanning the past 400 years, which they used to statistically examine “the relationship between milky seas globally and large-scale coupled atmosphere ocean phenomena…for the first time.”
The science here is interesting on its own merits, as the team refined predictions about where and when milky seas are most likely to occur, and linked them to broader oceanic and climatic forces. The radiant displays, powered by the marine bacteria Vibrio harveyi, are influenced by the Indian Ocean Dipole and the El Niño Southern Oscillation, and are commonly observed around the Arabian Sea and off the coast of Southeast Asia, according to the study.
“Given their spatial scale and biological nature, milky seas may represent a critically understudied large-scale movement of carbon and nutrients through the earth system, particularly so with bacteria playing a key role in the global carbon cycle both on land,” concluded the team.
But as with most studies in this category, the supplemental information is the star of the show. It’s such a treat to read through all these accounts of past mariners who found themselves on the decks of their vessels at night, looking out at a surreal seascape of milk, or snow, or silver.
“At a quarter before eight o’clock at night, a phenomenon appeared of the following nature, and to all on board of an unheard-of kind, which gave rise to transitory feelings of apprehension as to the vessel’s contiguity to danger,” wrote an observer in the log of the H. C. sloop Clive in August 1832. (Clive is an excellent boat name, by the way).
“Without any indication of a change in the elements, the ship was surrounder instanter (sic) by water as white as milk or snow,” continued the seafarer. “No line of horizon was visible; the dead white colour of the water close to the ship as it increased in distance from her very gradually brightened until, where I supposed the horizon to be, it assumed a silvery aspect, which increasing as it ascended became brilliant and dazzling towards the zenith, obscuring the stars and clouds which had before this visitation been distinctly visible.”
A similar tale unfolds over the course of dozens of collected entries. Some mariners threw fireballs into the ocean to literally test the waters, and many crews reported that tiny “animalcules” were seen under microscopes in buckets drawn up from the milky seas.
But the common theme across the centuries is an almost mystical quality to these encounters, which shines through (so to speak) in the ship logs.
“When looking into the sea at the height of the phenomenon, it was almost impossible to focus the eye and a slight feeling of vertigo was experienced,” noted an officer of the SS Ixion in a 1967 entry about a sighting in the Indian Ocean. “This eeriness could well have convinced the superstitious mariners of long ago that the ship would fall off the edge of the world during the night if navigated far from the shore.”
“It was like we were in the "Twilight Zone" and peering at a negative of the real world,” reported the crew of the USS O’Brien of a 1980 sighting near the Yemeni island of Socotra. “The seas were glowing with phosphorescence as far as you could see all around us…The phosphorescence was uniform and a bit lighter green or ‘whiter’ than the normal screw-generated green phosphorescence (kind of like the glow-in-the-dark plastic stars you can buy your kids). There were no breaks in the phosphorescence even with the waves.”
I recommend reading through some of the excerpts, which are filled with expressions of wonder, premonition, and good old-fashioned scientific curiosity. You gotta hand it to Earth. She knows how to put on a show.
Do These Lopsided Satellites Make Andromeda’s Butt Look Big?
The universe does not conform to our expectations. This is a common lament among cosmologists.
Over the past half-century, for instance, scientists across diverse fields have developed a framework called the standard model of cosmology, also known as the Lambda cold dark matter (ΛCDM) model, that accounts for a lot of the weird stuff we see in space. But if you search “challenges to the standard model,” you will get roughly a bajillion hits, as observations of the real universe frequently clash with the predictions of the standard model.
One of the most interesting conflicts is the behavior of dwarf galaxies that orbit larger ones, such as Andromeda, which is the nearest major galaxy to the Milky Way. The standard model, meanwhile, predicts that these satellite galaxies should be more or less isotropic in their distribution around their host, meaning that they should occupy a swarm of random orbits around a larger galaxy.
But in a new study, scientists found that Andromeda’s orbiters are weirdly clustered on one side. “All but one of Andromeda’s 37 satellite galaxies are contained within 107 degrees of our Galaxy,” said researchers led by Kosuke Jamie Kanehisa of the Leibniz Institute for Astrophysics Potsdam.
In other words, most of the orbiting galaxies are asymmetrically located on the side of Andromeda that faces the Milky Way. In standard cosmological simulations, this configuration is extremely rare, showing up in just 0.3 percent of cases. What gives?
The researchers speculate that the Milky Way might be exerting a tidal influence on Andromeda, thereby pulling its orbiters in our direction. But if this were true, you’d expect the satellites of the Milky Way to align in a similar asymmetry, given that Andromeda is about as massive as our own galaxy, yet there’s no evidence that this is the case.
“At present, no known formation mechanism can explain the collective asymmetry of the Andromeda system,” the team concluded.
You could ask the universe, but it’s just not very forthcoming about this kind of thing. Indeed, this is not the first time the movements of satellite galaxies have defied the standard model; I covered this eerie discrepancy a few years ago for Motherboard.
The discovery that Andromeda appears to be “an extreme outlier in the prevailing cosmological paradigm” is yet another sign that something is either wrong with a) the model, b) our observations, c) all of the above, or d) some other wild card that has yet to be identified. Place your bets.
An (Intellectual) Feast for Crows
Schmidbauer, Philipp et al. “Crows recognize geometric regularity.” Science Advances.
It’s well-known that crows (and other corvids) are among the most intelligent animals on Earth. You can kind of intuit this fact just from looking a crow in the eye—they have that “clever girl” vibe to them—but studies have helpfully provided empirical evidence they are capable of tool use, abstract thinking, and epic grudges, among many other proficiencies.
It got one team of scientists thinking: can crows do geometry?
“Animals’ sensitivity to geometric regularity has been found to be notably limited; nonhuman primates do not recognize geometric regularity in tests involving the perception of visual shapes, whereas humans do,” said researchers led by Philipp Schmidbauer of the University of Tübingen. “This result led to the interpretation that the recognition of geometric regularity could constitute a uniquely human ability.”
As a rule, don’t call anything uniquely human until you’ve tried it on crows. To that end, the team presented two carrion crows (Corvus corone), aged 10 and 11 years old, with a touch-screen showing different assortments of shapes. For instance, a simple starter test displayed six non-quadrilateral shapes, such as five stars and one crescent moon. A tougher test mixed in quadrilaterals—such squares, trapezoids, rhombuses—with one irregular four-sided shape.
Crows were tasked with detecting the “intruder” shape, which they successfully did about half the time, a rate that is well over what would be expected by chance.
“Our results, showing that crows spontaneously recognize geometric regularity in visual shapes, contrast with those from a study involving monkeys that failed to discriminate quadrilateral stimuli based on geometric regularity” a finding that challenges “the idea that intuitive shape geometry is uniquely human,” the team concluded.
To paraphrase a legendary animated newsman: I, for one, welcome our crow overlords.
Uranus Gets its Chakras Aligned
Lamy, L et al. “A new rotation period and longitude system for Uranus.” Nature Astronomy.
Last but not least, a day on Uranus just got 28 seconds longer. This is not because the planet has suddenly decided to slow down in mid-life, though it would be forgiven for the indulgence. Instead, the extra time is due to an update of its rotation period, which was measured by Voyager 2 in 1986.
Data collected during that flyby determined that the Uranian day is about 17 hours, 14 minutes, and 24 seconds, give or take about a half-minute. On paper, this small margin of error for a giant planet located about two billion miles from Earth is not too shabby. But the slight imprecision has actually been bugging astronomers who study the planet for a while, prompting a lot of new rotational estimates over the years.
Now, scientists have refined the Uranian day to a whopping six decimal points by tracking the planet’s radiant auroras for more than a decade with the Hubble Space Telescope.
“Here we use the long-term tracking of Uranus’ magnetic poles between 2011 and 2022 from Hubble Space Telescope images of its ultraviolet aurorae to achieve an updated, independent, extremely precise rotation period of 17.247864 ± 0.000010 h, only consistent with the Voyager 2 estimate,” said researchers led by Laurent Lamy of the Observatoire de Paris.
This update brings the Uranian day to 17 hours, 14 minutes, and 52 seconds, about 28 seconds longer than Voyager 2’s rotational estimate. The improved accuracy “will allow the reanalysis of the whole set of Uranus observations” and the novel approach “stands as a new method to determine the rotation rate of any object hosting a magnetosphere and a rotationally modulated aurorae, in our Solar System and beyond.”
We’re all in a Proustian search for lost time. Who could have guessed we’d end up finding it on Uranus?
Thanks for reading! See you next week.