GolfPopper 3 hours ago

I find myself, perhaps irrationally, quite irked that the picture headlining the article uses a picture of current Earth with rings, when Earth's surface 466 million years ago looked much different[1]. The paper itself [2] does have a map, although (understandably) not an artist's depiction. Most other sources covering the paper appear to have repurposed "ringed terrestrial planet" artwork, but I found one has an artist's rendition[3] to mollify myself.

1. https://dinosaurpictures.org/ancient-earth#450 2. https://www.sciencedirect.com/science/article/pii/S0012821X2... 3. https://www.yahoo.com/news/earth-had-saturn-rings-466-182200...

amelius 4 hours ago

Nice opening image, but what would the view be like from Earth?

  • KineticLensman 3 hours ago

    Off the top of my head, if the rings were a narrow band around the Earth, and were aligned with the terrestrial equator, they would be less visible from high or low latitudes. If they were aligned with the plane of the ecliptic, then they would be visible as a band following the 'zodiac constellations', and thus visible much further North and South.

    At night, in the shadow of the Earth, I'd think that they would be dark, perhaps even invisible. Perhaps moonlight would serve to illuminate them, depending on the relative position of the Sun and Moon.

    I'd guess they would look most impressive around and dusk. The particle density and albedo would influence whether they would be visible during full daylight. The ring density would affect whether they had sharp edges or simply faded out away from the centre.

    • BurningFrog 3 hours ago

      Only part of the visible rings would be dark at night. You'd see sunlit parts on both sides of the shaded part.

forgot-im-old 6 hours ago

May see rings around Earth again.. it's the expected state that space debris settles into after Kessler Syndrome.

  • keyle 5 hours ago

    I was about to make a snarky comment about starlink. It's getting harder to take a shot of the sky without one of those pesky floaties.

    • FooBarBizBazz 16 minutes ago

      I read that those things' orbits degrade in like five years tops. So at steady state, for a constellation of size N, you need to launch N/5 of them each year, with the attendant fuel burn. Seems like that kind of pollution is a bigger long term worry than the short-lived junk? On the other hand, until it does fall down, I suppose it's a risk to anyone who wants to launch up through it.

    • BurningFrog 3 hours ago

      They low orbit satellites are only visible while they're in sunlight near sunrise/sunset.

    • hggigg 4 hours ago

      Yeah this. I was 50 miles from civilisation in some mountains in central Asia last year trying to do astrophotography and I had to edit out the flying space trash after!

      • fooker 3 hours ago

        If you needed rescuing from there, or if a nearby village was affected by a natural disaster, this flying space trash is what's saving lives.

        It makes sense for the vast majority of people to prefer that against the slight inconvenience in editing out satellite tracks faced by a tiny tiny community of ground bases astrophotographers.

        • samegene321 3 hours ago

          Low orbit satellites are unnecessary for emergency/comm. Fewer, dimmer, satellites at higher orbits are actually cheaper, but LEO constellations are now subsidized by the military industrial complex (there is other value to be low).

          • Jtsummers 15 minutes ago

            > Fewer, dimmer, satellites at higher orbits are actually cheaper

            GEO satellites are pretty pricey. Each Milstar satellite cost $800 million, others in the same category are also in the hundreds of millions, WGS-11 was over $600 million. Starlink V2 cost $800k per satellite.

            And if you spent $800 million on a constellation of 1000 Starlinks, you'd have better coverage and bandwidth than the entire 6 satellite Milstar constellation put together for 1/6th the price.

            Digging around for more recent prices, GEO is around $100-300 million. That's still orders of magnitude more per satellite than LEO. At the low end this means you could get 100-400 Starlink V2s up there for the price of one GEO. One GEO that only covers part of the globe, versus 100-400 satellites providing global coverage.

          • jjtheblunt 41 minutes ago

            Aren’t you overlooking constraints on transmit power for mobile transmitters being better served my low earth orbit than higher orbits?

            • Jtsummers 13 minutes ago

              They're also overlooking the actual prices of GEO satellites versus LEO. LEO is much cheaper than GEO, there's a reason DOD and others are moving towards it and it's not that it's a fad. GEO has a few specific benefits but cost is not one of them.

        • hggigg 2 hours ago

          No it's really not. Please don't think suburban USA can be extrapolated to the middle of bloody nowhere.

          I might be able to get a message off, but how the hell do you contact the emergency services and who the hell is going to rescue me in a country with one rescue helicopter that was out of action at the time?

          In circumstances like that it's better to actually get some mountain safety training, have some procedures and other comms equipment in place. And importantly travel in a group with the right equipment (including 4 legged transport devices).

          As for the astrophotography that was opportunistic.

    • delichon 4 hours ago

      Debris left in orbits below 600 km normally fall back to Earth within several years. The Starlink constellation is at around 350 km and below.

      • forgot-im-old 4 hours ago

        Starlink is actually 550 km and Amazon's Kuiper at 620 km.

        But the missile interceptors for the orbital 'American Iron Dome'* in the news lately would be ~ 350 km.

        * 2024 GOP platform #8: https://ballotpedia.org/The_Republican_Party_Platform,_2024 which developed out of Elon Musk and Mike Griffin's initiative for their founding of SpaceX: https://wikipedia.org/wiki/Michael_D._Griffin#Career#:~:text...

        • samegene321 3 hours ago

          it's a (Grok) ai transcript, but I found this SpaceX/Starlink history fascinating. Detailing how Musk has been working with key people on (Reagan's) Star Wars 2.0 for decades: https://archive.today/D2zIG#:~:text=Shotwell

          The only explanation I've heard for Musk's political antics that makes cold sense.

          • kidme5 an hour ago

            whenever the orange president mentions going to Mars, it's in the same sentence as the military and his MAGA Iron Dome. He's failing to keep the lid on the cover story.

          • jajko an hour ago

            Don't look for cold sense in mr musk's adventures, just look at whole twitter saga. He is a overgrown child with brilliant mind but very little control of his emotions (on top or other real mental issues under variable control). My almost-5 year old son has in some aspects more emotional maturity than him.

            Doesn't mean that stuff ain't truth of course, but his recent conservative alignment has deeply personal reasons too.

            • kidme5 an hour ago

              he sincerely believes saving humanity means being a Strategic Defense Initiative front-man under the guise of Mars

  • sandworm101 5 hours ago

    There isnt nearly enough mass up there in all the foreseeable sat constellations. They need enough collective mass to overcome the extreem orbital inclinations/speeds we use for sats. For a visible ring to form, we would have to send billions of sats into high/slow orbits and then just forget about them for millions of years. Even then, they would likely form into mini moons first before those moons eventually broke up into rings.

    • JKCalhoun 5 hours ago

      I had to laugh thinking that we (or some alien race) might come across a ringed planet only to find its rings are made of orbital space junk from a long-dead species that once flourished on the planet.

      • McAtNite 3 hours ago

        This made me consider what sort of orbital archeology would take place. I imagine it would be a gold mine for anyone trying to study that civilization, and attempting to snatch pieces out of orbit would be a huge focus.

ChumpGPT 3 hours ago

> Planetary rings may be one of space’s many spectacles, but in our solar system, they’re a dime a dozen. While Saturn’s rings are the brightest and most extensive, Jupiter and Uranus and Neptune have them, too,likely the dwindling remains of shredded asteroids or comets.

Reading "The Ring Makers of Saturn", Dr. Bergrun suggests something very different.

nprateem 2 hours ago

The ring of Uranus. One of the wonders of the solar system.