“camped” out in Quebec, my son speaks better French than me and has corrected me all weekend, but we’ll see whose in charge when I poke him in the eyes two seconds before totality… Or squeal like a school girl as it approaches, we’ll see which happens!
Noticing a bit of misinformation here so let’s clear this up: take off your eye protection during totality. The corona is so faint you won’t see anything at all through eclipse glasses.
A minor accident had forced me down in the Rio de Oro region, in Spanish Africa. Landing on one of those table-lands of the Sahara which fall away steeply at the sides, I found myself on the flat top of the frustum of a cone, an isolated vestige of a plateau that had crumbled round the edges. In this part of the Sahara such truncated cones are visible from the air every hundred miles or so, their smooth surfaces always at about the same altitude above the desert and their geologic substance always identical. The surface sand is composed of minute and distinct shells; but progressively as you dig along a vertical section, the shells become more fragmentary, tend to cohere, and at the base of the cone form a pure calcareous deposit.
Without question, I was the first human being ever to wander over this . . . this iceberg: its sides were remarkably steep, no Arab could have climbed them, and no European had as yet ventured into this wild region.
I was thrilled by the virginity of a soil which no step of man or beast had sullied. I lingered there, startled by this silence that never had been broken. The first star began to shine, and I said to myself that this pure surface had lain here thousands of years in sight only of the stars.
But suddenly my musings on this white sheet and these shining stars were endowed with a singular significance. I had kicked against a hard, black stone, the size of a man's fist, a sort of moulded rock of lava incredibly present on the surface of a bed of shells a thousand feet deep. A sheet spread beneath an apple-tree can receive only apples; a sheet spread beneath the stars can receive only star-dust. Never had a stone fallen from the skies made known its origin so unmistakably.
And very naturally, raising my eyes, I said to myself that from the height of this celestial apple-tree there must have dropped other fruits, and that I should find them exactly where they fell, since never from the beginning of time had anything been present to displace them.
Excited by my adventure, I picked up one and then a second and then a third of these stones, finding them at about the rate of one stone to the acre. And here is where my adventure became magical, for in a striking foreshortening of time that embraced thousands of years, I had become the witness of this miserly rain from the stars. The marvel of marvels was that there on the rounded back of the planet, between this magnetic sheet and those stars, a human consciousness was present in which as in a mirror that rain could be reflected.
Well that is some spectacular prose, I am truly transported to a place where spirituality and science meet at a single point of grand mystery and realization that I have felt a few times in real life, alone in nature at surprising places and odd hours, but Saint-Exupéry has taken this all one further level up the rung.
To a level that my father actually lived, as an airplane pilot in Baja California back when the peninsula didn’t have a paved road, an isolated, remote place as yet mostly untouched by man.
One minor caveat, however:
a sheet spread beneath the stars can receive only star-dust
While I understand such a thoughtful writer was going for a feeling, surely with his talent he could have found a way to include windstorms, all the dust and sands they can sweep horizontally across the lands and over hills. The Rio De Oro region is in northern Morocco, surely it often gets blasted by powerful Saharan winds.
A sheet spread beneath the Moroccan sky most often receives desert-dust.
“Contrary to standard cosmological theories where the accelerated expansion of the universe is attributed to dark energy, our findings indicate that this expansion is due to the weakening forces of nature, not dark energy,” he continued.
I follow this stuff (as a non-physicist) so I understood it. It’s a pretty shallow article and mentions there there’s still evidence for the widely-accepted Lambda-CDM model. But like most coverage of MOND it declines to give good alternate explanations for specific key observations like the Bullet Cluster, gravitational lensing, and galactic outer rotational speeds.
So yeah a new observation that fits better with MOND than LCDM is certainly interesting, but it doesn’t flip the tables unless it does a better job explaining the prior phenomena too.
I understand the two theories and the difference between them, but when my brain tries to comprehend how gravity actually works I experience a comprehension failure.
Haha, well if it’s any consolation, nobody fully understands it. That’s why we’re still looking at various theories of quantum gravity or even random gravity.
oh boy, get ready people. it starts with a movie, then it’s a debut single, then you’re buying the fanzines, the hats, the shirts. this ends in commemorative plates.
Isn’t an event horizon just a question of being dense enough to bend light past the point of no escape?
A hollow planet supporting a detached core with enough density to have an event horizon seems kinda ridiculous… If even light can’t escape it, I don’t see some rocky ‘shell’ withstanding that much gravity. Any hollow section would have collapsed well before reaching the point of the planet’s densest point forming an event horizon.
What matters is the total mass of the black hole, not its density. If you replaced Earth’s core with a black hole of the same mass, the gravity you’d feel at the surface (or beneath the surface) would be the same. You’d only notice a difference if you were in the hollow region formed by removing the core.
The way I see it, the real problem with a planet like Earth is that because the inside is so hot, the inner parts are too soft to support their own weight, and the crust is probably too fragile to support its own weight. That’s not a problem, though, in an asteroid or a planet that’s solid all the way through.
Depending on the mass of the black hole, the “shell” doesn’t need to be a shell it could be effectively completely solid with an atom sized black hole at the centre.
PBH’s as discussed in this article have pretty wild mass ranges, so anything is possible. It’s entirely possible to have black holes so small they can’t easily absorb new matter as they’re smaller than protons. Tiny black holes only have large surface gravity, nothing noteworthy at a distance.
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