Tidally Locked Worlds

[@awsumguy-bh9pz]

Red dwarfs are like abusive fathers they randomly beat their children with massive solar flares.

[@chrisdriedger3875]

They just don't know any better 😔

[@HoldstarX]

When you are factoring the collision rate in red dwarf system, the moment you say "they can have more planets densely packed" you are automatically creating an anti-comet shielding for inner planets. Just a single jovian type gas giant in the outer reaches of such system would probably clear most of nearby comets fairly quickly :) Still, I can't wait till the day we actually get pictures of other star systems. For me, it can't happen too soon :P

[@pointyorb]

Something to note based on what I've observed in Universe Sandbox: The closer you put a tidally locked planet to its star, the thinner the twilight band gets. The atmospheric pressure on the day side will climb to inhospitable pressures, as the water of the oceans there all evaporates and gets sent into the atmosphere, so the day side could actually feel incredibly humid, granted you don't get crushed to death first.

[@Shalomjoyyy]

I love the way Isaac speaks. Very calming

[@gammaechofoundationproductions]

Issac, I have no trouble understanding you, however, the volume of this particular video is quite low.

[@isaacarthurSFIA]

Quick note if you're leaving comments with questions, make sure your settings on google plus or youtube or whichever are set to "Public" or I can't reply directly. @Zeo stark - I use Blender for the animations, still rather new to it, and nearby stars does sound like an interesting topic for a vid.

[@nikunashi3494]

+Isaac Arthur I can perfectly understand your speech, thanks man.

[@32353235e]

What about planets with extreme axial tilt? Say with 45 degrees angle or more?

[@marcopohl4875]

could you do some blender tutorials? i have some difficultys with those already out there, maybe a beginner would make simpler ones?

[@kingad8869]

Game of Thrones is science fiction!!! Watch Preston Jacobs. You'll like it!

[@imperialgaming3689]

Can you redo this video and talk about how life and other ecosystem could work in a planet like this.

[@TrineofFire]

I appreciate the time you took to make this video. I'm trying to write a science fiction story and the species I primarily focus on, live on a tidally locked world that's roughly 40% larger than Earth and resides in a Binary Star System. So this video has been very helpful in giving me some insight as to how life on their world evolved, especially since the cause of the tidal lock was due to a massive asteroid impact, rather than the effects on it's three moons and the stars this planet and her satellites orbit. (If it's implausible for complex life to exist after such an event, then hey, I get explore the evolution of complex, hearty lifeforms.) I've also been really curious as to how oceans and atmospheres would behave considering the planet does not spin. So, hopefully when I come up with my artist's rendition of a Tidally Locked world, it'll be at *least* some-what accurate.

[@saganl7857]

+MrZash Ha, I came here as well to try to understand tidal locked planets since I'm working on a sci fi idea my self involving a locked planet. :D

[@isaacarthurSFIA]

+MrZash Sorry for the long delay, didn't even see this comment till Sagan L replied to it, I actually might suggest to both of you, if you're facebook users, a forum called "Worldbuilders and sci-fi writers" on there, concepts range from softer sci-fantasy to ultra-hard SF and writers from dabblers to published professionals but a lot of fun notions get kicked around and there's a lot of scientists there to cross check ideas against, though IMO plot should never take second place to scientific accuracy. :)

[@TrineofFire]

Isaac Arthur Basically: "Just have fun and make it a decent story." Yeah my brother tells me that all the time. ;) I've done some more research into the subject and I'll just design my aliens around what evolution related challenges an intelligent species might face on a particular world. Simple enough; thanks Richard Dawkins and thank you Isaac for this fantastic video!

[@isaacarthurSFIA]

+MrZash You're very welcome, and from my perspective I always enjoy a story where the guy's done his research and thought it through, even in fantasy genre stuff like Brandon Sanderson's stuff, the world feels more real. I like that L2 moon concept, improbable but you can always hang a lantern on it, toss-away line about the improbably stable moon "Lagrange's Triumph" or something.

[@cxidp]

Isaac, love your videos. I understand you and am awed by your discussions. Please help us by continuing your work.

[@gringusbingus736]

Dude don't ever feel bad for the way you talk. What you say is amazing though. I've never enjoyed hearing about wild scie ce fiction concepts until finding your channel. Great job!

[@patricklions9066]

my new favorite channel

[@generalbrock2000]

Your videos are great. I really hope you keep making them.

[@isaacarthurSFIA]

General Brock Thanks! I plan to.

[@zico739]

Rewatching these OG videos.

[@wilde4945]

Interstellar cosmology is a fascinating and intricate subject. Very well explained in layman's terms. Excellent.

[@PITU-f7f]

best videos explaining the ins and outs of a tidally locked planet to a red dwarf. I loved the graphics and the image of what the view of the dwarf sun look like from the planet... our planet is amazing, petty we mostly fail to realise it.

[@SailorBarsoom]

Enjoyed this. There seem to be a lot of writers setting stories on tide-locked worlds orbiting red dwarfs!

[@SailorBarsoom]

And now we have seven such planets to consider, all in the same system!

[@katt5159]

Beautifully done, thank you!

[@templebrown7179]

Isaac, thanks for the great video. I like the way you've presented the material and found it easy to understand, despite the slight speech impediment you mentioned at the beginning. Please continue to produce more videos! Subscribed and liked!

[@templebrown7179]

I was curious what kind of mic you use and how you mitigate background noise, as well. Your audio sounds very crisp and clean.

[@isaacarthurSFIA]

+Eisen Faust Glad to hear it. I switched to using my webcam's mic (a Logitech C270, nothing fancy or pricy) at some point, I think when I made this video I had already done so, I had two other old mics I tended to use before that. Nothing special for noise mitigation, mostly there's just no noise to mitigate, I live in a quiet rural area and rarely have the windows open. Mostly I just shifted to doing much shorter takes, usually a paragraph at a time, and listen to them while sipping some tea or water, then redo them if they came out bad, probably about half the time.

[@brainwavestobinary]

Great video - very informative! It goes much further in depth than other videos I've seen about tidally-locked, "eyeball" planets. For fictional world-building purposes, it's been essential.

[@complex314i]

I regret writing this because I hate bugs but: "How much would a lifeform with an exoskeleton be protected from the radiation on an eyeball world?" The first life to crawl out of our oceans was not fish trying to walk, but giant sea scorpions.

[@liamjohnston2000]

Perhaps not an exoskeleton like arthropods on Earth, but a covering of cells containing pigments similar to those found in plant leaves. However, instead of helping with photosynthesis, these pigments would absorb the damaging UV radiation and could provide some protection to the organism.

[@mitchh3092]

@@liamjohnston2000 Sort of like the Turian homeworld in Mass Effect; the animal life evolved to have slightly reflective metallic plates to deal with higher (relative to earth) radiation on their homeworld (due to a weaker magnetosphere and thinner atmosphere than earth, I believe).

[@Jarretman]

I really enjoy your videos and I find them very refreshing. Keep up the good work!

[@isaacarthurSFIA]

+Help Me Thanks!

[@templebrown7179]

+Help Me Love the Ivy-Mike picture you're using as an avatar!

[@Baleur]

I say this with the greatest respect and zero sarcasm intended. I actually love your speech impediment. It makes you, you. No need to apologize for it.

[@TheKatanaDan]

I only discovered this channel maybe a week ago, but you're fast becoming one of my favourites! Informative, well written and presented, and I hope you don't get too offended by the remarks about your voice, I just assumed you had an unusual accent! As a stutterer for many years I sympathise with what hurdles you may have faced with a speech impediment. Consistently superb video as always, looking forward to getting caught up with them all!

[@isaacarthurSFIA]

+TheKatanaDan Glad you're enjoying the Channel! My grandfather had a stutter, which made us an amusing pair as he tended to speak slow and deliberately around his pipe stem while at that age I tended to sound like someone had taken a record and set it on 2x speed. Just one of those thing, we've all got an anomaly about us and people are hard-wired to notice anomalies, you just get used to people noticing your own and there are way worse ones to have then a speech impediment or stutter.

[@ivangarreg]

Excuse me Iforgot to tell you that you videos are incredibly good I've seen almost all of them. And concerning the scottish accent I won't give up

[@kevin1f1f1f]

This was SUCH a good video, thank you for doing a great job explaining.

[@annakroeger2833]

I have no problem understanding you at all thank u for making these videos I very much enjoy them

[@michaelkeefer5674]

So glad to found your videos. This is stuff have interested me for decades. Used to design fusion powered starships when on back shift (had to be there just in case) and did not have any real work to do. Also designed a space colony. Kind of like the sunflower design, but everything important and breakable sort tucked inside where micro meteors would not get to them.

[@thewolfyartistproductions4208]

Tidal locking, a better love story than twilight

[@rosecityandbeyond]

I love educational youtube channels. I'm subbed to everything from ASAPScience to ZoggFromBetelgeuse, and I just found another one! xDDD

[@rspielvogel]

Fascinating video. I'm actually a science fiction writer (who tries to stay as true to the science as possible) in the middle of writing a book about a pre-industrial society taking place on a tidally locked world. One thing that I've struggled with is that there are quite a few different interpretations of how the atmosphere on a tidally locked planet would affect its wet-dry regions. I had initially assumed (like many people) that the light side would be a desert and the dark side would be a frozen tundra with the twilight zone being a (comparatively) temperate rain forest. However, Hadley atmospheric circulation would predict that the light side would be particularly hot and wet, creating tropical rain forests across the light side, and that as the hot air cooled and fell across the dark side it would create cold barren deserts. Anyway, I'm curious to hear your take on this.

[@isaacarthurSFIA]

+Ryan Spielvogel That was Carone's conclusion anyway and I'm inclined to agree with her, the paper came out a few months after this video did or I'd have discussed her team's conclusions, it was certainly the most thorough look at the subject I've heard of. But as mentioned in the video we already had pretty good reason to believe the desert/tundra with slim band between of habitability was probably overly-pessimistic. A nicely boiled-down version of her findings is at the link below and you may find it useful. Hope it helps, and good luck with your worldbuilding, its always good to see authors putting a good focus on the science. serious-science.org/the-climate-and-habitability-of-planets-with-eternal-day-and-night-sides-5289

[@rspielvogel]

+Isaac Arthur Excellent! Thank you. That article really helps. Part of the nice thing about writing fiction is you get to work backwards from what you want your end conditions to be back to what kinds of starting conditions you would need to get you there. This article is going to allow me to set my starting conditions (what size planet and what orbital period) I would need in order to get the conditions needed for my book to work.

[@SailorBarsoom]

I think you and Chris Wayans are the only two people I've seen consider libration due to eccentric orbits. That weird day/night cycle, where a gigantic sun rises over the horizon, changes its mind and goes back down over the same horizon... What a world to live on.

[@annoyed707]

I'm wondering if there might be a sweet spot where with the right year length the libration might provide something like a 24 hour day-night cycle in part of the twilight band?

[@tysondennis1016]

Here’s my idea on how life would evolve on a tidally locked world: -Has two brains working in alternating shifts, so that one brain is awake while the other is asleep. This overcomes the issue of no day/night cycle. -Life near or above the surface has higher radiation resistance, to handle the solar activity. -Life has adapted to constant wind patterns, using the winds to fly or disperse spores.

[@michaelkeefer5674]

If your tide locked world is lucky enough to have a deep ocean that goes from the bright side to well into the dark side, it will even out the temperature extremes. There will be monsoons and hurricanes coming from the warm waters of the bright side that will dumping rain and heat deep into the dark side. This result in cold currents flowing to the bright side cooling it down.

[@AuntieXoXo]

Love your vids, keep up the good work man

[@Gnarsley]

Greetings from Lakewood, Ohio Thank you for your videos!

[@Epsilonsama]

Great video. I was looking into more on how a Tidal Locked planet would be like and this has been a good video on said subject.

[@zackblack2066]

Excellent video and series! Keep up the good work!

[@450aday]

3:13 looking at picture from space, the sun is very white, yet there is still clearly a subtle tint of yellow to it. the center is white, So the appearance of planets around other stars would be subtly influenced by the stars color.

[@charlessmith2643]

yep you got me back at the computer here we go again :-) cheese it's nice to have my science Guru :-)

[@MrMusic4676]

I assume a tidally locked planet around a Red dwarf can be habitable around the Equator area in front of the star, if the planet is just farther enough away from the star that it is no hotter then 40C around the equator area and warm near the the Twilight area and just cool along the Twilight area. But then again i've heard in 'In a nut shell' video, that some Red dwarf's can be 1/ hostile to it's planet's, 2/ they can form large star spots that can condense there light to up to 40% for month's, which would coarse ocean's to freeze over, 3/ throw out large super powerful solar flare's and 4/ double their brightness in minute's which can strip away a planet's atmosphere.

[@Wirrn]

I think you might have the magnetosphere bit backwards - a magnetic field wont do anything to stop UV and X-rays, what it does is block solar wind. Without it the atmosphere would get stripped off (possibly what happened to mars) and its the atmosphere that absorbs most of the radiation.

[@briang8766]

Thank you for the videos.. I have no trouble understanding you either Mr Arthur 😊

[@rockochimp545]

I think you sound fine, if people give you a hard time about "r" they can go intercourse themselves. No need for you to explain, excuse or apologize. A polite reminder about cc is all well and good, but you don't need to pander to the lowest common troglodyte. I expect most of your viewers are not so simple minded as to care about how good a pirate impression you can do. Please keep sharing your work with us, I like exploring these ideas through your perspective. Thanks again!

[@leftover7766]

Yeah but if cc helps download scientific information quicker into brain, then it's a good thing. I turn it on and it improves comprehension, which is Isaac's goal, I believe. Thanks Isaac - cc is very useful, but would be even if your voice were less unique. And, yes, there is a certain charm to the Barry Chripke simulation.

[@rockochimp545]

Well put, I agree.

[@SailorBarsoom]

Back in the Eighties I watched a movie with an old pirate in it. The movie was rated Aaarrr!

[@rockochimp545]

Sailor Barsoom What's a pirates favourite letter? You'd think it was Aaarrr! but it's actually the C....

[@GameDevByrne]

i concur i've never found Isaac even slightly difficult to understand.

[@MrMusic4676]

Living on a tidally locked planet around a Red dwarf, its like having area's of Arid climate on one side and Antarctic climate on the other, with area's of Temperate and Mediterranean climate in the middle. We (human's/animal's) could also live in the desert's, just along the desert edge's, where its not too hot and gets just enough rain, like in Egypt and right next to the Ice shelves like in Greenland. There maybe billion's of Red dwarf's out there with billion's of tidally locked planet's with land and sea ET's living in this small habitable area!

[@Lyle-xc9pg]

obviously

[@jonathanhensley6141]

Great video

[@jonathanhensley6141]

Pluto video was very interesting ty.

[@Zero-pe3iq]

Speaking of the fermi paradox I find it quite funny to imagine 100s of advanced civilizations contemplating such things in a universe filled with others just like them. Not to mention perhaps in some galaxy far far away there may even bein 100s of separate alien interstellar empires interacting and maybe even building their own galaxy(like in an video you hadn't made at the time of this video making stars) that could fit into a space a few light years across. But none of us will ever know cause that galaxy is outside the observable universe.

[@dmingophd]

This video should gain more attention now, due to the discovery of the Trappist 1 system.

[@Teankun]

One thing I that may factor with a tidally locked world is that if it is in a binary+ star system is that companion stars may offer light to the far side of the planet for some periods of time, perhaps at least enough for photosynthesis.

[@sinsforeal]

Do you know about space engine? I think that would be an excellent program for showing animations

[@isaacarthurSFIA]

Yes I've been pondering using it but I've already invested a fair amount in to learning blender and in a day or two I get my new up-gunned PC that ought to let me push the envelope more on making animations, but if that doesn't come out very well I probably will start using Space Engine for some stuff.

[@blakekendall6156]

A 2X mass rocky planet towards the middle/far end of the habitability zone from its red dwarf star would be a good eyeball methinks. Not so much bigger that the core would be too solid to create a very large magnetic field, and greater surface area at a greater distance means more "twilight band" capable of having a thick enough atmosphere and strong enough magnetic field for land life to exist. Though tidally locked, with some orbital eccentricity and a wobbly tilted axis, there could be some real weather, and the larger size with thicker atmosphere means greater retention of heat overall, meaning the dark side would have some reasonably warm spots.

[@rhuiah]

Great video.

[@jjt1881]

I love your videos, specially this one and the other about tidal locking. They are up to date, pedagogic, easy to understand (from a visual point of view) and quite interesting. Are you planning to do a new video specifically on the newly discovered planet Proxima b or the Alpha Centauri system? I would love to watch it.

[@isaacarthurSFIA]

I've been getting asked about that a lot recently so I probably ought to, I'm a bit leery though of doing one since there really isn't a ton of info yet.

[@isaacarthurSFIA]

Also, not sure what happened to the comment [youtube eats them sometimes I think] but you asked how bright the two stars are from Proxima's perspective, and the answer is they would look like normal star's in terms of width but would be terribly bright, on par with out own full moon. Backwards, Proxima itself would be quite bright too from a planet around them, but a good deal dimmer. I'd probably need to run the exact numbers but I would guess they'd all be day-time visible and even Proxima ought to be bright enough to see decently by at night.

[@rasverixxyleighraq1509]

I don't know why but I've had the idea in my head for a while of living on the night side of a Tidally Locked Planet slightly too close from the habitable zone.The day side would be hot but winds and circulation would make the night side pleasant. We could have 24hr Night perfect for observatories and star parties, it'd be lols lol

[@liamscienceguy8153]

Rasverix Xyleighraq that WOULD be cool

[@wartome3196]

I wonder if a planet can lock to a sun with the planets moon locking in between the sun, blocking the most extreme sunlight. Wouldn’t take allow more variations in the golden zones?

[@AndDiracisHisProphet]

Nice one. I have a question though. My astrophysics lecture was a few years ago, so i might not remember correctly. But wasn't the definition of "red dwarf" a star big enough to initiate hydrogenfusion (i.e. more that 8% of the mass of our sun), but small enough, that it "mixes" completly through convection (i.e. less than 20% of the mass of our sun). And in the video you say that red dwarfs go up to 50%. Also, in some of yout other videos you show some science fiction novels, (Niven, Stross, etc) and i wondered if you also know Stephen Baxter? Two years ago, or so, the published a novel called "Proxima" where he describes a colonization of a (hypothetical) planet around....well Proxima Centauri, hence the name :) I found it quote good, as almost all books by him. Isn't he not so well known in the US?

[@isaacarthurSFIA]

+AndDiracisHisProphet Not quite, the fully convective ones end at 25% solar mass, but red dwarves is up to 60% Solar Mass. Big category, and a bit of an artifact term same as Sol being a 'yellow dwarf', it was smaller than most stars we observed when classifying the things but is in the top 5-6% of stars mass-wise. Red Dwarves really ought to be two categories, fully convective and not, but I can't see anyone changing it now. This also why in some of the videos I'll remark about quarter-mass stars being arguably the ideal ones for Kardeshev 3 civs because they burn all their fuel so you might Starlift bigger ones down to that mass to extend their lives. And yeah I know Baxter, he's pretty good, not a personal fav, which is a bit surprising since he writes diamond-hard SF, but then so does David Brin and I never get enthralled by his stuff the way I do some others. The UK does seem to be churning out a disproportionately large percentage of the better SF novels the last couple decades though, its regrettable the books don't usually do quite as well state-side. Adams, Pratchett, and Banks, all sadly deceased, Hamilton, Stross, Mievile, Reynolds, etc. I'm behind on Baxter though, haven't read Proxima yet.

[@AndDiracisHisProphet]

Hm, strange. I learned that the definition of red dwarf is "fully convective". Maybe that is different in german literature from english? About Baxter, he is my all time favourite, when it is about "modern" science fiction. From the ones I read (that is all which are translated, because I'm too lazy to read whole novels in english, although there might be something lost in the translationprocess), I only disliked "Ares" It was really boring. I can recommend Proxima, though and looking forward to Ultima. But that ist really going offtopic now ;)

[@isaacarthurSFIA]

+AndDiracisHisProphet I tried looking up Rote Zwerge Stern but my comprehension is too degraded to pick out any differences. I read a lot more beer bottle labels then astronomy journals when I was stationed in Germany apparently. It may be different, but a lot of this stuff tends to be a bit vague anyway, I just double checked wiki and its saying up to .5 Solar masses and .35 SM is fully convective, when I looked somewhere else this morning to make sure I hadn't erred it was up to .6 SM and

[@stefanr8232]

Stephen Baxter's book Proxima is a story about inhabiting a tidally locked planet. How could a book be more on topic?

[@liamscienceguy8153]

Yeah, convection goes up to .45 solar masses

[@ChrisBrengel]

6:53 Mercury gets more than twice as much sunlight when closest to the sun than it does when furthest away. 8:20 "But I'll nitpick it [Game of Thrones] anyway because I'm ticked about season 5 book deviations." LOL!

[@Zzeo7]

Nice video, :) suggestion for future video: best nearby candidates for human visits.. the animations are a nice touch what app do you use?

[@petrfedor1851]

Wonder how water cycle in atmosphere would play into it. Sufficiently massive ocean in center of sunny side could create pattern of storms that transport heat relativly far into the dark side and make climatic differences less stark. Also epic storms.

[@petergahan9076]

Doesn't Asimov call them 'ribbon worlds' in Foundation series?

[@robhenry4616]

Goodness Isaac, do you really think that a day = a year in tidal lock? Personally, I doubt anyone would think of a day as a sidereal day, outside astronomical circles. That leads on to me wondering why you didn't cover resonance tidal locking such as Mercury (try telling those colonists that they don't have one day every two years, but three days every two years). Will that be in a later video?

[@WadcaWymiaru]

Moon is tidally locked so didn't spin: upload.wikimedia.org/wikipedia/commons/c/c0/Lunar_libration_with_phase2.gif it try but libration is too strong...

[@stefanr8232]

I believe life on a resonant planet would not be much different from life on a slowly rotating planet. Tidal locking changes the climate dramatically.

[@MauMenzori]

Hello, Isaac. I am an amateur sci-fi writer, and while studying astrophysics and general physics in order to wisen up before bringing my "child" into the world (my first novel), I am coming to this channel every week, to watch each single video you've posted till now. I got a question for you: In one of my stories, I got a planet Earth that has LOST its moon over the course of history. After the Sun swells up into a red giant (and considering the scenario where the star's gravity actually pushes the planets AWAY, rather than eating them), is there a chance our planet could get tidally locked to the Sun itself, due to its sheer gravitational force? Oh, that would help the plot so much, if it did... I'd appreciate any help you can provide. Thank you so much, and keep up with the great videos. Big fan here.

[@glitchysoup6322]

Oh, you are using Blender too at 5:38. You should use highter sampling to avoid grainyness. Othervise video is good.

[@PhysicsPolice]

Great video! Do you have any sources which go into more detail for tidally locked worlds? I'm working on a science fiction story set on such a planet. Thanks!

[@isaacarthurSFIA]

Ludmilla Carone has done some impressive weather modeling on them since this video came out, articles by her or explaining her work though you might just want to contact her directly.

[@Tarbabyification]

I was dreaming of such a story the other night, and this is why I was watching this video how has your story gone so far it's been 3 years please tell me I would love to know

[@JAMESLEVEE]

I have been considering ways in which an M-dwarf planet in the Goldilocks zone would not be tidally locked. Perhaps an eccentric orbit, or a satellite that is tidally locked and actually makes the day longer than the year? An axial tilt that means the planet spins along a different orientation than the ecliptic?

[@SailorBarsoom]

With an eccentric orbit, just a little bit, you get the day/night cycle described at 5:36 and I like that: nice and weird, but real. Imagine the sun slowly rising over the course of 36 hours, then changing its mind and going down the same way just as slowly -- rising in the east, then setting in the east. Except in the other hemisphere the sun sets in the west, then rises in the west. Three (Earth) days of light and then three of night. What a place to live.

[@ruth540]

Wah 💕 his speech is so cute, wtf

[@terrybradford3727]

Had to pause. If the GoT ticked you off for the season 5 deviations.... did you even get to season 8, lol. Just started binging your content, excellent stuff. You must have been great on staff duty or out in the field.

[@Tounushi]

In March 2017 they proposed an artificial magnetosphere for Mars by using a massive magnetic emitter that shields Mars in its magnetotail. How would the orbital mechanics allow for such a craft with one of these worlds?

[@ZeDlinG67]

So cool, recently the now called Trappist-1 system got discovered; it supposed to have many tidal-locked planets - and a lot of misinformation. (I think) We would enjoy your thought on them :)

[@isaacarthurSFIA]

I've been tempted to cover it

[@ZeDlinG67]

I'm sure I'm not the first one to mention it ;)

[@samsamsamsamsamanilla5281]

@Isaac Arthur can a tidally locked planet have a moon, or would it just line up eclipsing the planet and not revolving around the host planet?

[@tylersizelove7521]

So it would be feasible to assume the weather would be hellish considering the clash of two extreme temperatures on either side? Or at least heavy hurricane like winds pushing from the hot side to cold? Would that make sense?

[@Ian_sothejokeworks]

Maybe I'm being naive as to the amount of effort about which I'm talking, but couldn't we just tidally "unlock" a world? I mean, it should be just a matter of energy transfer by passing massive enough items around it, in much the same way our moon is slowing us down, but in reverse. Swing a lot of high-mass objects around it, and use the drag to get it moving at a faster rotation. Hell, enough small mirrors might do it, but why not bring in an artificial moon? You could help by using a little extra fuel on giant ships to slingshot out when leaving the planet. Could this work?

[@stephenhaag2358]

I remember a documentary on tv that said if we had a red dwarf for a sun then the sky would be a hellish blood red, I guess they thought we were too stupid to comprehend the truth

[@kampkrieger]

u said in the tidally locking video that the energy goes into heat, but where does the angular momentuum go?

[@SailorBarsoom]

In the case of Earth and Moon, the two grow farther apart.

[@kampkrieger]

thank you :) can you back this up with some source or explanaition why?

[@SailorBarsoom]

kampkrieger OK, you remember the the tidal bulge, which the Moon pulls on to slow down the Earth? Well the Earth is still rotating faster than the Moon orbits, so that bulge is always a bit ahead of the Moon. As the Moon pulls on the bulge, the bulge pulls on the Moon, speeding it up. This slings the Moon into a higher orbit. Here is the BBC on it: www.bbc.com/news/science-environment-12311119

[@kampkrieger]

no I didn't but is is explained in the article :) Thanks a lot again

[@kampkrieger]

so to come back to my original question: The momentum is still the same because the momentum which the system lost in the spin of the moon is equal to what it has gained by having the two bodies circling each other at grater distances whcih is of more momentum, right?

[@youngepicurean8282]

There's seems to be a lot of interesting science here. If these ideas are not your own, where did you get them from? If they are, have you published work in any of the astronomy journals?

[@isaacarthurSFIA]

+Alan Reyes They're mostly well-trod ground, much predating me by decades, though still a bit speculative, depending on the video. I can provide some references if you want to look into anything specific in more detail but generally I just write the scripts out from my own knowledge accumalated over the years, jumping to articles or wikis to double check stuff. The only original concept to me in the videos is the Dyson Dilemma, and even that is just a simple extension of the Hart and Hart-Tipler conjectures.

[@michaelatwell8724]

Roughly how long do you suppose it takes for a planet in say, a one week orbit, around a M dwarf 1/8 the mass of the sun, to become tidally locked, if it started with a 6hr day? Is it a guarantee planets this close will become tidally locked?

[@markcreamer6179]

What about the possibility of polar continents and an equatorial ocean?If there were another planet a little farther out, exerting some tidal forces on it, Wouldn't that act to form an equatorial bulge of water which would be dragged around the equator and with that ocean flowing around it would act to distribute the heat a little more evenly. [ assuming it has an ocean's worth of water in the first place]

[@mrk45]

Given the extreme temperature differences on such worlds, would they be more susceptible to hurricanes?

[@isaacarthurSFIA]

Quite possibly, shortly after this video got made a fairly impressive model of the weather on such worlds was done by Ludmilla Carone, who suggested fairly extreme weather might be possible in some setups. I'm still inclined to think not, rotation seems to play too big a factor in weather to think you'd get extreme weather without it, but she makes a pretty compelling argument otherwise.

[@stevenpilling5318]

Only once before in my experience has it been noted that red dwarf stars aren't actually red. That's a fact that almost every space artist gets wrong. As for the ability of a world of such a star to generate that all important geomagnetic field, that would depend a lot on not only it's rotation rate, but it's composition, density and age. It's worth noting that even little Mercury, with a spin of 55 days, can still generate one. Also, the closer to its sun a planet forms, the denser it's liable to be. Despite all the negatives, I retain hope that red star systems can contain worlds that, if not naturally habitable, can be reclaimed as such without undue effort. If not, what a waste of real estate!

[@ibeyan]

Hello, nice informative video you got there. I'm currently working on a sci-fi novel based on a tidally-locked world. While fictions remain fictional, I still do want some reality check on this. A few years ago there was an article suggesting that simulations showed it could be possible for a planet like this to have a balanced heat circulation, given a thick atmosphere and a lot of oceans, so that the temperature and wind caused by temperature difference can be much more bearable for life. Will it simply be so cloudy that you can't even see the colour of the sky that way, or it very highly depends? I just want it to be more believable, not just throwing every handwavium to make it work.

[@GoranXII]

For life, even if a planet is tidally locked _now_ it doesn't mean it was some millions or billions of years ago, so maybe life evolved _before_ it became tidally locked.

[@robertrose4759]

Watching

[@sandro5535]

Can tidally locked planets be at a distance so the sun side becomes goldilock zone? Would that be more ideal for life than rotating planets?

[@reformedorthodoxmunmanquara]

Don’t mind me, I’m just learning how these planets work to create a fictional world with its own civilization

[@guilhermecunha3363]

would it help the planet to rotate around itself always pointing one pole to the sun? Would it help develop climatic changes? or a magnetosphere?

[@annoyed707]

Like Uller, from the H. Beam Piper novel Uller Uprising?

[@kefkaZZZ]

Since you are interested in GoT, would you care to discuss possible solutions for the orbit of their planet? I have heard some very interesting hypothesis about the reason for their long winter as it relates to orbit.

[@TheMarcobnc]

does the centrifugal force make gravity stronger on the bright side and lower in the dark side if the planet orbits fast and very close to the star?

[@isaacarthurSFIA]

Huh, no one's ever asked that before. Yes, I believe it would, not a lot, the distance from the Sun is still way higher than the radius of the planet, and that's a linear relationship, but while not a big effect it would be measurably lower on the dark side than bright side, particularly at the 'noon' and midnight spots, probably still less than a percent even in the most extreme cases though.

[@dominusbalial835]

I think it'd be nice if you revisited this video and explained it more in depth than this one, although it's still a well detailed video.

[@Phelan666]

Wouldn't the winds on these planets would be devastatingly fast, though. Like, hundreds or even thousands of mph?

[@isaacarthurSFIA]

+Yellow King Not that I've ever heard of, I'm not really sure what the mechanism for that would be.

[@Phelan666]

Isaac Arthur If the sun heats one side of the planet at all times, the atmosphere will try to reach equilibrium.

[@isaacarthurSFIA]

+Yellow King Yes but the models generally show only high speeds in upper atmospheres, same as on Earth, and ground based ones averaging less than Earth Normal. Consider Venus, a near tidally-locked world, the upper atmosphere is very fast but the ground wind is just a few mph.

[@joshuahurley1957]

Mega Earth covered in water? Tidally locked. Massive hurricanes? Giant mountains? Hot Jupiter with tidally locked moon?

[@IblameBlame]

You make it sound as though a magnetosphere protects against UV or X-ray radiation even though it only protects against radiation consisting of charged particles

[@closair]

I would like to see a video on 'lava/fire' worlds

[@straytakermusic]

Speech impediment? Maybe I have a listening impediment! have you ever considered that??? (great vid as always, btw)

[@isaacarthurSFIA]

:)

[@anihroxxor]

At first I thought that mirrors where "mills" :O

[@benthomason3307]

hey, I've had an idea I want your thoughts on. I've been contemplating a tidally locked world that orbits a binary star consisting of a red star and a blue star, so that it does actually have a daytime cycle, just one that alternates between red and blue instead of light and dark.

[@alphalex88]

After watching a few of your videos I was very impressed with your logic on the matter of intelligent extraterrestrial life. If I may, would you entertain my hypothesis on said matter? Since there are no known exoplanet in the habitable zone that contain a tidally locked satellite in size comparable to ours with respect to the size of the exoplanet, intelligent life cannot exist until such standards of current and fluidity are met, or their like.

[@isaacarthurSFIA]

Problem is, our catalog of exoplanets is horribly biased to 'very large' and 'very close to its sun', as we build that up with more hits on Earth-ish sized planets at Earth-ish temps, we'd probably still intially be missing those with big moons, just as those are yet harder to see, though since we're bound to focus on those examples the most, we probably will get them. A big moon is a classic suggested 'filter' for life, and I think it remains a good one, but until we've got at least a few hundred earth analogues to look at and have accuratetly enough to see if they'd have a big moon, it's a little too speculative still as a concept.

[@alphalex88]

@@isaacarthurSFIA I must agree with you. Exoplanet cataloging is minute and biased to these things; and to add insult to injury, the current methods of finding exoplanets is only relatively accurate at best. Recently, I have become aware of a certain inexcusable denial of unalienable factors necessary to the existance of intelligent life by astronomers and astrophysicists around the world. The Cosmological Constant is a good example of such factors. Once probabilites become subject to such tedious scrutiny the possibility itself of intelligent life becomes increasingly improbable. It may seem sadistic but only when try to stay objective and true to science do I draw this conclusion. Otherwise, I do hope for the opposite.

[@maximkazhenkov11]

A magnetosphere doesn't help against UV and X rays since they're not charged.

[@annoyed707]

But it does help protect an atmosphere, from which a UV-blocking ozone layer comes, and which does help with X-rays.

[@jamieknight2144]

Mercury isn't exactly tidally locked though the sun rises and sets on all parts of the planet. There would be no sun side / dark side. There would be no stable terminator zone.

[@isaacarthurSFIA]

+Jamie Knight Yes, neither Venus or Mercury is tidally locked, in spite of their long days, though Mercury is in a Synchronous Orbit, just not 1:1

[@RokkuReal]

+Isaac Arthur it's just you mentioned Mercury casually which is often mistaken for being 1:1 tidally locked when it's not. In terms of this video only 1:1 tidally locked planets would give the terminator zone worthy or terraforming so it's worth clearing that up really. Mercury would not be suitable. Love you videos though but needed to mention that.

[@jamieknight2144]

+Isaac Arthur replied with my other account for some reason technology doh!

[@isaacarthurSFIA]

+Anthony Coleiro Hmm... script says I mention Mercury three times, but none of those seem to imply Mercury was locked, but I'm often bad at telling when I'm being confusing and I don't hold to the scripts word-perfect... do you know when it was? I like to flag annotations on bits of the videos where I make mistake or am unclear.

[@jamieknight2144]

+Isaac Arthur okay, watching again now and Mercury is mentioned in the first 30 seconds. So far that implies it's one of these 1:1 you are talking about. I'll keep watching for the other references.

[@hansolav5924]

it could just be a quirk of my mental makeup, but I figure I can understand you because of my familiarity with both the language and the topic of space or future phenomena. just a thought.

[@Baalur]

English is not my first language and I have no formal education in STEM. I too find Isaac to be easy to understand and very pleasant to listen to. He can explain complex topics in a way that makes them easier to understand without dumbing them down too much.

[@SuperZarrabal]

Volume is too low. I would have no problem understanding you, but at work too much exterior noise.

[@thycreatorsource903]

I need to contain her immediately. We need to put her in custody so no more life will be in danger.

[@88happiness]

Thanks, went back and watched the companion, first.

[@shamusfarmer7057]

What about the "lobster oceans"?