Lumipuna

Here is a recap thread of the ten-part discussion series I wrote on the astrodynamics, evolution and likely appearance of this putative ring. It was incredible, nerdy fun. @MaijaKarala @MontanaRosslyn @JoschuaKnuppe @HodariNundu @IsaiahCTorre

@kestinen @yejiioutsolds @IshkaMamushka @suchnerve Scandinavia is logistically kind of an island, in relation to the "heartland" region of Europe. It's also kind of peripheral, which feeds into the "not really Europe" mentality. Some maps of "Europe" don't even go as far north as Helsinki!

@yejiioutsolds @IshkaMamushka @suchnerve We are not even island nations in the Nordics (except for Iceland and half of Danes), but we refer to rest of the continent as “Europe”. Like if you are talking about travelling to “Europe” it means anywhere south of Kiel canal but nothing north of it

Brits saying “Europe” like they aren’t part of it is one of the more linguistically bizarre consequences of Brexit. Y’all are Europeans too lol

@DXenephon @LydiaJ007 Reverse Earth where deep ocean plains correspond to barren high plateaus, trenches to high mountain ranges, shallow seas to fertile lowlands and lakes/depressions to seamounts/islands.

@LydiaJ007 dang why didnt i think of that it would make more sense

This map is so interesting to me, imagine an infinite plane of desert punctuated by oases like this once every million kilometres

@Alaygroundss @suchnerve I was just wondering how much solar energy is directly absorbed as heat by such panels. They look kinda dark, but that's in part because some of the light energy is converted to electricity. There's also a good amount of reflection at certain angles.

@suchnerve How does it fare with the decreased albedo, just out of curiosity

Solar panels’ cooling ambient air relative to not having solar panels is one of those things that really should be talked about more often - that ~20% of sunlight that gets turned into electricity would have otherwise been turned into ambient heat. On a large scale, it adds up!

@ItsAndyRyan @HouseChambers @Aguirre115622 Ah, thanks for clarification!

@lumipuna @HouseChambers @Aguirre115622 Yes, and the equivalent to Francis I would be 'World War I', rather than 'First World War', and the former expression didn't start getting used until just before WW2 started.

People say this is a lot, but there's no implication in "First World War" that more will come, just that it hasn't happened before. When I said "This is the first time I've had sex", I had no expectation that it would even happen again.

@Idronan93 @CenozoicDragons I don't see why an earthlike tide would be necessary, though it'd come as a byproduct if you somehow made Venus rotate much faster. The tidal force Venus experiences from Sun alone is roughly equal to what Earth experiences from Sun + Moon during the strongest tide.

@CenozoicDragons True, if we are trying to give Venus Earth's rotation and tidal characteristics. If we accept some degree of variation from Earth standard then Ceres could work. Putting Ceres on a close orbit for example.

I was gonna say how you probably couldnt have polar glaciers on Venus, but if you're cleaning its atmosphere, speeding up its rotation, giving it one of Saturn/Jupiter's moons, and hitting it with enough comets to cover 71% of its surface in water then solar mirrors seem doable

@ItsAndyRyan @HouseChambers @Aguirre115622 - the correct style *until* there is another pope named Francis. Of course, the names of previous popes had been serial, so it was easy for editors to casually assume that this one is, too.

@ItsAndyRyan @HouseChambers @Aguirre115622 Thanks. I wouldn't consider it self-evident to call the first of a kind "first" as long as it seems like a unique fluke. BTW, I recall that the late Pope Francis was sometimes mis-styled in the media as "Francis I", to the point that Vatican had to clarify that this is not -

@HouseChambers @Aguirre115622 @ItsAndyRyan Did anyone ever call it just "World war" while the sequel was not yet evident? (I bet people mostly called it "the war" while it was their current or most recent conflict, but that's leaving the identification up to context.)

@Aguirre115622 @ItsAndyRyan Some journalists were calling it the first world war from day one. With the emphasis being on 'world'.

@DrPeever Great concept, but I must point out that the ring would have occurred about 100 million years later.

#MarineMay Day 22: Newfoundland, 560 million years ago. In the golden glow of twilight, a dying Haootia lays on the beach. If only it could see the brilliant way the light makes the sea look like liquid gold, and the celestial rings wrapped around the horizon. #paleoart

@JellybeanKimchi @aedison Then again, so is the glass marble.

@aedison It's one crinkly crunkly oblate spheroid.

they tried to do a lot of propaganda on me as a kid. weird stuff, too, like claiming that the earth is as smooth as a glass marble when it’s very obviously not, there’s whole mountains and valleys, the earth is actually extremely bumpy

@PietaPotato @TetZoo Common frog spawning reaches northern Finland. (We already have big tadpoles at my local puddle in Helsinki - but the puddle is in danger of drying up if we don't get a lot of rain soon.)

Frog beginnings 🐸

@Veevuzuela @Hahathatsnice @vvictorman_uel I rarely go to the beach (I wear a speedo when I do), but it's vaguely possible that someone has mistaken my hernia bulge for big junk.

@Hahathatsnice @vvictorman_uel Not if ur a #grower

I just want everyone with a penis to know that in my 27 years of existence I have only ever noticed one boner in public. we unpenised folk can really be clueless

@ExploreCosmos_ May I ask, what implications does this system have for Martian auroras? I hear they aren't bright enough to be visible to the naked eye, but I'd like to understand why that is. Also, do the auroras concentrate on the day side or rather around the daylight terminator?

Mars does not have a global magnetic shield like Earth, but it still has to deal with the solar wind: a constant flow of charged particles from the Sun. Instead of a strong internal dipole field, Mars forms an induced magnetosphere, produced when the solar wind interacts with its upper atmosphere and ionosphere. A new study reports a clear detection of the Zwan-Wolf effect inside the Martian ionosphere, using in-situ measurements from NASA’s MAVEN @NASAMars spacecraft during the aftermath of an interplanetary coronal mass ejection that hit Mars in December 2023. The event strongly disturbed and compressed the Martian plasma environment, making a normally subtle process large enough to detect. The Zwan-Wolf effect is a plasma process first studied mainly at Earth. In simple terms, when magnetic field lines carried by the solar wind are compressed near a planetary obstacle, the resulting magnetic pressure gradients can squeeze plasma along those field lines and away from the region where the flow is being slowed or blocked. At Earth, this happens near the magnetopause, where the solar wind is forced to move around the planet’s magnetic shield. The compression can produce a local drop in plasma density because the plasma is being pushed out along the magnetic field. In the paper, the same kind of effect is observed at Mars, but in a different setting: not around a strong planetary dipole, but within the ionosphere of an unmagnetized planet where solar-wind magnetic fields are draped around the dayside of Mars. MAVEN observed several large magnetic structures near its closest approach to Mars, at an altitude of about 185 km. These structures had steep leading edges, with magnetic field enhancements of around 50 nanotesla, roughly 40 percent above the background field. As these compressed magnetic fronts passed through the ionosphere, MAVEN measured clear decreases in ionospheric plasma density, typically around 30 to 40 percent, together with a tailward flow of plasma. The interpretation is that the increased magnetic pressure at the front of each structure squeezed ionospheric plasma along the draped magnetic field, producing the density depletion and flow pattern expected from the Zwan-Wolf effect. This is important because the Zwan-Wolf effect had usually been associated with planets that have strong magnetic fields, especially Earth. Mars shows that the same physical mechanism can also operate in induced magnetospheres, where the obstacle to the solar wind is not a dipole field but an atmosphere and ionosphere conducting electrical currents. The researchers suggest that the effect may actually be active at Mars most of the time, but usually too weak to be detected by plasma instruments. During quiet conditions, the magnetic pressure changes are small, so the resulting plasma deflections are probably below instrumental resolution. During the December 2023 coronal mass ejection, however, the system was so disturbed that the effect became amplified and observable. The study also shows how space weather can temporarily reshape the plasma environment of planets without global magnetic fields. A strong solar eruption did not simply “hit” Mars from outside; it launched disturbances that propagated into the induced magnetosphere and down into the ionosphere, creating compressed magnetic structures capable of moving plasma around. The observations do not suggest that these structures caused major direct atmospheric escape during this event, because the plasma was not accelerated enough to exceed escape velocity. But they do show that extreme solar-wind conditions can drive real, measurable motion and heating in the upper atmosphere of Mars. In broader terms, this result adds a new piece to the picture of how Mars interacts with the Sun. Even without an Earth-like magnetic shield, Mars is not passive. Its ionosphere, the solar wind, and the draped interplanetary magnetic field form a dynamic system where pressure, magnetic fields, and plasma flows constantly respond to one another. The detection of the Zwan-Wolf effect at Mars shows that processes once thought mainly in the context of magnetized planets can also appear in the thinner, more exposed plasma environments of unmagnetized worlds.

@OJoelsen Just wait till the melting of Greenland's ice sheet (in no small part thanks to US Republican climate policies) takes Louisiana off the map.

Governor Landry: “–I found out that Greenland wasn’t on the map until Donald Trump put it on the map.” —DR

@CSMFHT x.com/WeirdMedieval/…

Well it's technically a song, but it's... complicated

@dove_of_babylon I once thought TMNT would make hugely more sense if the characters were not turtles, but turkey chicks growing up as atavistic dromeosaurs.

@JPMajor Thanks. So I was five hours earlier.

@lumipuna About 8pm local time Sunday, which would be 0100 GMT Monday

Tonight's just-past new Moon...just a sliver of a crescent

@HallvardHolte One of those has even spread into certain Uralic languages, as in Finnish pieru.

There are hundreds, if not thousands, of interesting words we simply cannot now reconstruct in Proto-Indo-European. They have simply been lost in time. But we can reconstruct TWO words for "fart"

@hyperdiscogirl @bpodgursky - only species found in Europe (its range extends no further west than Finland and Estonia). These two were both described by Linnaeus in 1758, and originally named as the same species Mus volans ("flying mouse") and later revised into different species and genera.

@hyperdiscogirl @bpodgursky Because they needed to have different specific names, and the southern one was described first, presumably because a part of its range was targeted by European colonization early on. There is, however, a volans in another genus: Siberian flying squirrel Pteromys volans, the -

It turns out that flying squirrels live in most of the continental US, but you almost never see them because they are 100% nocturnal. I learned this recently because as I knocked down a dead tree in my backyard a family of squirrels flew out and I thought I was going insane.