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Earth's mountains form in millions of years, Moon ones near instantaneously
- nwallin 6y agoThis article is barely mentions formation of mountains on Earth. The article is almost entirely about lunar craters, lunar central peak craters, and lunar peak ring craters. Interesting article, terrible headline.
- echelon 6y agoIt's editorialized. The original title of the article was changed from this: "Exploring the marvel that are mountains on the Moon"
- temp0826 6y agoThe craters are interesting, but one of my favorites is the “cosmic thunderbolt” theory for the gigantic gash on mars (Valles Marineras) https://www.thunderbolts.info/tpod/2005/arch05/050408marineris.htm https://www.thunderbolts.info/tpod/2005/arch05/050408mariner... (Link warning, use gigantic grain of salt and a hard sceptic hat...fun nonetheless)
- EdwardDiego 6y ago> This article is barely mentions formation of mountains on Earth. Isn't that pretty well understood already?
- garmaine 6y agoThey both are.
- m4r35n357 6y agoNow I have a tense headache!
- sushshshsh 6y agoA bit frustratingly, they mean "geologically instanteously" which is not the same as "instaneous as per human perception". I'm not sure how long rock takes to cool after an asteroid impact, maybe days, maybe months or years depending on how large of an impact and how cold the surroundings (no atmosphere soooo....) These mechanics are not discussed in the article and are instead just dismissed as "negligible"
- wahern 6y agoWouldn't molten rock simply flow and flatten? Even if not yet rigid, I'd assume the mountains do effectively form instantaneously (i.e. seconds or minutes), possibly flattening some as they slowly cool. EDIT: The PBS NOVA special "The Day the Dinosaurs Died" describes the mechanics of the Chicxulub impact starting at about the 33 minute mark. It's as instantaneous as one would intuit, given the magnitudes involved: > NARRATOR: The asteroid had punched a hole nearly 20 miles deep, gouging a crater 124 miles wide. Over 40,000 cubic miles of rock were displaced, rising into towering mountains. > JOANNA MORGAN: So, this is an absolutely amazing event, because that happened in less than two minutes, and if you think of it, mountains the size of the Himalayas were formed in seconds. > NARRATOR: As the mountains collapsed, they formed what's known as a "peak ring," found only in the largest of super craters. It's the only peak ring left on Earth; the next nearest is on the moon. https://www.pbs.org/wgbh/nova/video/day-the-dinosaurs-died/ https://www.pbs.org/wgbh/nova/video/day-the-dinosaurs-died/
- sushshshsh 6y agoSee, now this is an enjoyable fact. It is interesting to think that all of the forces involved in the collision will finish propelling themselves into each other within 2 minutes. One would think that it would be a little bit longer than that, because the transfer of energy between two cars in a car crash is over in a few seconds. But an asteroid colliding with a planetoid seems like it would take longer, given the amount of mass involved and the amount of deceleration that needs to take place (x km/s to 0.0000000 km/s)
- wahern 6y ago
- kempbellt 6y agoMountains on Earth are formed by tectonic shifts and volcanic eruptions, which, yes, take millions of years. Mountains on the moon (aka: crater walls) form nearly instantaneously because of a violent impact. You can make instant mountains on Earth too. Downside is, it'll probably kill off most life on the planet.
- Natsu 6y agoWe have a few craters already, e.g. - https://www.meteorcrater.com/ https://www.meteorcrater.com/
- HenryKissinger 6y agoNow I want to hike a mountain on the Moon. My Instagram needs new content.
- behnamoh 6y agoThe second one is an amazing close up photo of a lunar mountain.
- molmalo 6y agoIt's interesting how my mind had some trouble processing some of those crater images, because I saw initially some of them as circular buttons, going up from the surface, instead of craters going down. I had to stop looking, and look back several times before my mind could actually see some of those pictures correctly.
- globular-toast 6y agoSame. One in particular still looks like a button for me.
- narag 6y agoIt has happened to me since I was a child, at the time of Apollo. My trick was turning the photo upside down so the light aligned with the room source.
- AaronM 6y agoI can't imagine the size of object that formed the Valhalla crater on Callisto. The central region is 360km across, and the diameter of the entire basin is 3,800km. That's a distance on earth from LA to Arkansas!
- LeifCarrotson 6y agoAnd the whole equator of Callisto has a circumference of 15,100 km. Proportionately, that would be a basin the size of the Indian ocean!
- tracerbulletx 6y agoThere are mountains on earth that formed in a few years too, and in fact most mountain ranges form pretty quickly as far as geology goes.