Speculoos-2c: A new potentially habitable earth(news.uliege.be)
news.uliege.be
Speculoos-2c: A new potentially habitable earth
https://www.news.uliege.be/cms/c_16795199/en/speculoos-discovers-a-potentially-habitable-super-earth
137 comments
Using a type of beer, TRAPPIST, as 'Transiting Planets and Planetesimals Small Telescope' wasn't bad either
[0] https://en.wikipedia.org/wiki/TRAPPIST-1
[0] https://en.wikipedia.org/wiki/TRAPPIST-1
Trappist is not a type of beer. It is a type of Catholic monastic order. They just happen to make decent beer (and jam, and many other things).
https://en.m.wikipedia.org/wiki/Trappists
https://en.m.wikipedia.org/wiki/Trappists
Trappist is not a type of beer.
Ok I guess in English the correct term is indeed 'trappist beer', but in Dutch 'trappist' is used to refer to the beer as well as the monk/nun; there's a lot more talking about beer than about those monks obviously, so you can imagine that for me 'trappist' means 'beer' no matter what language so pardon my linguistic mistake :)
Ok I guess in English the correct term is indeed 'trappist beer', but in Dutch 'trappist' is used to refer to the beer as well as the monk/nun; there's a lot more talking about beer than about those monks obviously, so you can imagine that for me 'trappist' means 'beer' no matter what language so pardon my linguistic mistake :)
Same in French. I guess that whenever one sees the word trappist in a conversation, beer comes in mind first. Unless you are in a history class.
In Hungary, Trappist is first and foremost a cheese.
I would even call it the default cheese, though like many cheeses it was apparently invented in France:
https://en.wikipedia.org/wiki/Trappista_cheese
I would even call it the default cheese, though like many cheeses it was apparently invented in France:
https://en.wikipedia.org/wiki/Trappista_cheese
So this is a category error much like saying French is not a type of poodle. I assure you, it is, just as, well, two can play at this game https://en.wikipedia.org/wiki/Trappist_beer .
The link you posted shows the opposite: Trappists brew many types of beer, though arguably Trippels are the most common lately.
Saying Trappist is a type of beer is like saying French is a type of poodle — if you used the label only to refer to a poodle bred in France.
A more apt comparison is saying Bordeaux is a type of wine. Bordeaux is a region in France; it is well-known for 5-6 types of wine; any Bordeaux wine that qualifies for AOC proudly displays its Bordeaux heritage on the bottle.
Saying Trappist is a type of beer is like saying French is a type of poodle — if you used the label only to refer to a poodle bred in France.
A more apt comparison is saying Bordeaux is a type of wine. Bordeaux is a region in France; it is well-known for 5-6 types of wine; any Bordeaux wine that qualifies for AOC proudly displays its Bordeaux heritage on the bottle.
Or Champagne, which are different kinds of sparkling wine made in Russia:
https://www.foodandwine.com/news/russia-champagne-law-sparkl...
(I see myself out now.)
https://www.foodandwine.com/news/russia-champagne-law-sparkl...
(I see myself out now.)
Which raises the question[0], "Why French poodle?" Is there a non-French variety? Wikipedia indicates not [1], although they probably originated in Germany. [2]
[0] Not "begs". Never "begs the question," even if I am being pompously pedantic. [0']
[0'] https://en.wikipedia.org/wiki/Begging_the_question#Vernacula...
[1] https://en.wikipedia.org/wiki/Poodle [1']
[1'] TIL the word "cynalogy"--"the study of matters related to canines or domestic dogs." https://en.wikipedia.org/wiki/Cynology
[2] Also, while the Germans refer to the breed as "Pudel," the French call them "Caniche". So of course in English we call them <"French"> <German word>.
[3] Rabbits! They went down this hole!
[0] Not "begs". Never "begs the question," even if I am being pompously pedantic. [0']
[0'] https://en.wikipedia.org/wiki/Begging_the_question#Vernacula...
[1] https://en.wikipedia.org/wiki/Poodle [1']
[1'] TIL the word "cynalogy"--"the study of matters related to canines or domestic dogs." https://en.wikipedia.org/wiki/Cynology
[2] Also, while the Germans refer to the breed as "Pudel," the French call them "Caniche". So of course in English we call them <"French"> <German word>.
[3] Rabbits! They went down this hole!
There are category category errors being committed on all sides. The confusion is arising from the word "type". To some, a "type" of beer is a style of beer characterised by common ingredients, methods and appearance. To others a "type" of beer may be as loosely defined as simply the kind of container it is stored in (can, bottle, draught).
And the type of beer they make is known as Trappist Beer, which is what the project is named after. See: https://www.eso.org/public/news/eso1023/
In my opinion, H0LiCOW (H0 Lenses in COSMOGRAIL's Wellspring) was a bit too much, trying too hard.
I am currently reading a paper [1] about the Far-side Array for Radio Science Investigations of the Dark ages and Exoplanets (FARSIDE).
[1] https://arxiv.org/abs/2209.02216
[1] https://arxiv.org/abs/2209.02216
Reminds me of Calvin and Hobbes' "Get Rid Of Slimy girlS"
A speculoos is a belgian biscuit.
Someone had fun coming up with a backronym I think!
https://en.wikipedia.org/wiki/Speculoos
https://en.wikipedia.org/wiki/Speculoos
Cant wait for MITRAILLETTE next to my TRAPPIST
Your wish has been granted :
https://en.wikipedia.org/wiki/TRAPPIST-1
That's an Herstal thing and it's already being used but for a different kind of products, not for space stuff.
And Mallomars. Always seemed like an sf/fantasy name already.
I am still not over the whole Biscoff scandal.
These scientists are doing their part to keep the original name alive.
What scandal!? I love Biscoff.
Sounds like a name for dog treats
I always thought they were German, but apparently the origin has not been conclusively tracked. They are called Speculaas in Dutch and Spekulatius in German
Also a great sandwich spread!
An orbital period of 2.73 days would mean there's no (earth like) seasons and agriculture would not be constrained to growing things at specific times of the year. A wheat farmer could split their farm into sections and be sowing and harvesting continuously.
That's assuming there isn't a cycle from freezing to boiling every 2.73 days.
That's assuming there isn't a cycle from freezing to boiling every 2.73 days.
That close to a star, the planet's rotation is probably tidally locked with its orbit, which means there's no diurnal *or* seasonal cycle. There's a summer hemisphere in permanent daylight; a winter hemisphere in permanent night; and a temperate twilight zone in between.
Solution: train-farms! Choo-Choo!
That would be as windy as Contrevent
Probably not. It's not hard to notice that while volatiles may flow from the hot side to the cold side, it's generally a one-way trip. Most attempts to model such a planet as habitable even on the thin strip involve trying to hypothesize some way that the volatiles could end up circulating rather than simply making the one-way migration, but personally I'm yet to hear a convincing way that could happen. And that's for the lower bar of "is life possible at all", not the much higher bar of "could we be happy living there".
YMMV, since it's all opinion and conjecture right now.
But in general I wouldn't expect much wind. The hot side is in vacuum because the only volatiles there are the ones just baked out of the fried ground or perhaps some volcanic activity, and the cold side is in vacuum because everything's frozen, and if there is some tiny pressure gradient you'd never notice the resulting "wind" as the vacuum flows past you, probably at rates roughly comparable to what the ISS experiences as "wind" in its low Earth orbit.
YMMV, since it's all opinion and conjecture right now.
But in general I wouldn't expect much wind. The hot side is in vacuum because the only volatiles there are the ones just baked out of the fried ground or perhaps some volcanic activity, and the cold side is in vacuum because everything's frozen, and if there is some tiny pressure gradient you'd never notice the resulting "wind" as the vacuum flows past you, probably at rates roughly comparable to what the ISS experiences as "wind" in its low Earth orbit.
The theological implications of finding planets even more hospitable than earth will be interesting.
Given that humans evolved to live on Earth, isn't it quite unlikely that we'll find planets that are more hospitable (to us) than Earth?
Invasive species evolved to live in the environment in which they evolved. Wouldn't it be quite unlikely that they'd find environments that are more hospitable (to them) than their native habitat?
It is quite unlikely! Most species don't turn invasive.
The mutants will find the other planets more hospitable.
Mirroring the fact that the cephalopod eye doesn’t have a blind spot unlike the vertebrate one.
Why do you say that?
Come to think of it, most major religions don't treat the earth as something special for humans. In the Abrahamic faiths it's specifically not our natural home, which is why we have so many issues. In the Hindu faith, from what I understand, it's also a place of suffering we are ultimately trying to escape. Buddhism also has much the same view.
Come to think of it, most major religions don't treat the earth as something special for humans. In the Abrahamic faiths it's specifically not our natural home, which is why we have so many issues. In the Hindu faith, from what I understand, it's also a place of suffering we are ultimately trying to escape. Buddhism also has much the same view.
Buddhism tries to escape from all forms of the existence (31 realms - or dimensions of existance) , not just from this earth or universe.
Oh yes we still have theology. I don't know why.
But as long as good books like Scott Alexanders Unsong tell me that American Pie is a song about the old testament, I do get entertainment out of it.
Training your mind to find patterns everywhere can be fun, unless you get QAnon out of it. Or, IMHO, religion that influences states or bothers non-followers. Contrast the good things, though: The aforementioned authors shows in Unsong that "Harry Belafonte - There's a Hole in the Bucket" is actually about the singluarity in AI/AGI development.
Training your mind to find patterns everywhere can be fun, unless you get QAnon out of it. Or, IMHO, religion that influences states or bothers non-followers. Contrast the good things, though: The aforementioned authors shows in Unsong that "Harry Belafonte - There's a Hole in the Bucket" is actually about the singluarity in AI/AGI development.
http://unsongbook.com/ for the curious:
“Erica,” said Ana calmly, “you’re going about this the wrong way. When Aaron is like this, you can’t argue against him. You have to beat him at his own game.”
“What?”
“For example,” said Ana, “Aaron, I propose that the Chevy does not represent the Tribe of Levi, but rather the Tribe of Issachar.”
“Huh?” I asked. “Why?”
“Because,” she said, with an ethereally beautiful smile, “a Chevy is a car.”
“AAAAARGH!” I said. “AAARGH AAAAARGH AAAARRGH AA – ouch!”
“Erica,” said Ana calmly, “you’re going about this the wrong way. When Aaron is like this, you can’t argue against him. You have to beat him at his own game.”
“What?”
“For example,” said Ana, “Aaron, I propose that the Chevy does not represent the Tribe of Levi, but rather the Tribe of Issachar.”
“Huh?” I asked. “Why?”
“Because,” she said, with an ethereally beautiful smile, “a Chevy is a car.”
“AAAAARGH!” I said. “AAARGH AAAAARGH AAAARRGH AA – ouch!”
Makes me wonder how much of the day sky is taken up by the star during daytime. Would be quite the view at that distance.
The innermost of the planets is about 2.8 million kilometers away from a star with a diameter of 217,000 km, so the angle (in radians) would be about 217,000/2,800,000 = 0.0775 radians or about 4,4 degrees. The sun is about 30 arc minutes or half a degree, so this star would have about 9 times the diameter, or 80 times the area of our sun.
(Double-check: this planet is about 1/50 as far from its sun as earth is from our sun, and its sun has about 1/7 the radius of our sun. That would give a rough estimate of the relative size of that sun in the planet’s sky of 50/7, so say 7 times as large as our sun is to us)
I would call that large, but not enormous.
(This ignores effects on perceived size of differences in the light spectrum and brightness of the two stars and differences between the atmospheres of this planet and earth)
(Double-check: this planet is about 1/50 as far from its sun as earth is from our sun, and its sun has about 1/7 the radius of our sun. That would give a rough estimate of the relative size of that sun in the planet’s sky of 50/7, so say 7 times as large as our sun is to us)
I would call that large, but not enormous.
(This ignores effects on perceived size of differences in the light spectrum and brightness of the two stars and differences between the atmospheres of this planet and earth)
That's roughly the size of Jupiter at a distance roughly 7 times that of the moon from Earth. At those distances you could probably see features of the star the same way we see craters on the moon.
It's a sphere next to a point source of light.
So I'm gonna guess... half?
So I'm gonna guess... half?
They didn't ask how much of the planet is covered in light. They mean how large does the star appear in the sky from the planet's surface.
Wheat is hard to grow in permanent twilight. And, with no water, because it is all frozen onto the night side.
This is no more earthlike than Mars.
This is no more earthlike than Mars.
That's gonna make it tough to keep track of when the pumpkin spice latte goes on sale. "Shoot, I missed fall again, guess I'll have to wait 48 hours for it to come around again!"
Given that most of the emitted light is infrared, there would be other challenges.
Interesting, but if we have a hard time keeping this one habitable we'll likely have a much harder time traveling 100 lightyears and terraforming this one to be organic. It's fun to think about but we're centuries from such capabilities(if possible at all)
As it's so much closer to the star, doesn't it mean it is much more seismic?
Probably. And certainly tidally locked, so 1 year = 1 day, with a permanently boiling day side, a hard-frozen night side, and a temperate, twilit ring straddling them.
All moisture would naturally migrate to the dark side and freeze there, permanently, if it doesn't sublimate away into the vacuum left after all the air is blasted off the day side.
All moisture would naturally migrate to the dark side and freeze there, permanently, if it doesn't sublimate away into the vacuum left after all the air is blasted off the day side.
Solar power production on the day side would give amazing efficiency, except for maintenance hell maybe.
I wonder if we could extract energy in other ways, like using the cold side for data centers (cheaper AC), or large pipes to extract the moisture from the cold side and heat it in the day side, to generate energy.
I wonder if we could extract energy in other ways, like using the cold side for data centers (cheaper AC), or large pipes to extract the moisture from the cold side and heat it in the day side, to generate energy.
I always day dreamed of a way to extract energy from the heat gradient between cold and dark sides. Possibly a huge pipe with a heat exchanging fluid at higher latitudes.
But with the prices on solar in recent years, I think that’s mostly discarded.
But with the prices on solar in recent years, I think that’s mostly discarded.
Those are local prices. You're forgetting about the expense of shipping, and I'm guessing the last mile problem in that particular set of logistics is a big one. Finding skilled laborers in local manufacturing might also be pretty expensive, so offshoring will be much more favorable even with the higher shipping fees.
You can stand up a thermoelectric panel exactly at the terminator, and collect energy by transferring heat from its day to its night side. The night side would be radiating to -270 degrees Celsius, warmed only by whatever convective air is around.
> temperate, twilit ring straddling them.
That sounds like a cool sci fi setting
That sounds like a cool sci fi setting
2312 by Kim Stanley Robinson has a city on Mercury that stays at twilight on the terminator, but being on a rotating planet, it has to keep moving on a massive track. Until it doesn't.
Throwing something older than the sibling comments onto this: Jack of Shadows by Roger Zelazny (1971).
https://en.wikipedia.org/wiki/Jack_of_Shadows
https://en.wikipedia.org/wiki/Jack_of_Shadows
The City in the Middle of the Night by Charlie Jane Anders from a few years ago has this exact premise. It was nominated for a Hugo - I thought it was just OK.
Even a tidally locked body can still liberate (as the moon does) so the terminator would at least move around over some fraction of the surface. Maybe together with a dense atmosphere that could be enough to redistribute the heat and keep the dark side from freezing out the gases?
"Librate". It probbly concentrates the ice closer to the center.
With enough atmosphere, like Venus, and some libration, I guess you might be able to get convection cells going enough to distribute heat. But really, the galaxy is absolutely lousy with planets. if you are equipped to get there at all, there is no need to make do in a hellhole.
All of these dim-star photosphere-hugging planets are an artifact of how we are obliged to find them. There are certainly myriads of planets that just need a half-billion years with some algae to become idyllic vacation spots.
With enough atmosphere, like Venus, and some libration, I guess you might be able to get convection cells going enough to distribute heat. But really, the galaxy is absolutely lousy with planets. if you are equipped to get there at all, there is no need to make do in a hellhole.
All of these dim-star photosphere-hugging planets are an artifact of how we are obliged to find them. There are certainly myriads of planets that just need a half-billion years with some algae to become idyllic vacation spots.
[deleted]
It would be great if one day we could visit planets such as these, even if just with robots.
I mean, the ethics of commiting your descendants to life aboard a generational ship is very sketchy.
I mean, the ethics of commiting your descendants to life aboard a generational ship is very sketchy.
I would gladly take a one way trip to one of these planets. provided I have a way of reaching there and spending at least 1 day alive there.
100 light years is no joke - but if the math on this is correct https://physics.stackexchange.com/questions/612645/does-spec...
I can leave say when i'm 60 and hopefully reach star at age 70. Trade-off I'm willing to do
I can leave say when i'm 60 and hopefully reach star at age 70. Trade-off I'm willing to do
Yes with a 1g rocket you can travel millions of light years in less than 80 years, when you come back earth is millions year older. In the future people will only live a billion years from now.
Ethics have a cultural and temporal context: if you believe strongly enough in the expansionary imperative of humanity, you would gift the generational ship's inhabitants with a suitable religion.
The ethics of creating descendants at all are sketchy. Once you've gotten past the fact that you are inflicting a possibly-unwanted life which will definitely include suffering, and certainly end in death, onto a soon-to-be-conscious being who is not yet capable of giving consent, the specifics of where that life takes place are not so significant.
It's possible store billions of humans as embryos that are grown and raised by robotic parents upon arrival. And it should also be possible to genetically engineer those humans to be better suited to that new planet's environment.
Though, by the time we figure out how to do that, "we" probably won't be purely biological, naturally evolved beings any longer.
Though, by the time we figure out how to do that, "we" probably won't be purely biological, naturally evolved beings any longer.
100 light-years is out of reach for humans, I would say :D
At 1g constant acceleration, including deceleration, it's only 9 years. A flyby is only 5 years [1]
[1] https://www.omnicalculator.com/physics/space-travel
[1] https://www.omnicalculator.com/physics/space-travel
Where would you get the energy to accelerate constantly for nine years?
That's the time passing in the vessel, not bad but still it means that such a mission would have to be completely self-sufficient and not rely on anything on/from Earth…
Not necessarily, if we could reach significant fractions of light speed. The subjective travel time can be shorter than 100 years, and approaches zero as you approach the speed of light. (Photons don’t experience time, so to speak, they are everywhere on their trajectory at once.)
As your target speed approaches the speed of light, the energy required aproaches infinity
Of course. But it’s a common misconception that traveling a distance of N light years will take at least N years subjectively. At something like 70% of light speed the subjective time already drops below the distance number: https://physics.stackexchange.com/questions/109776/how-long-...
suppose we have the tech to travel at a significant fraction of light speed, how long will it take for the spacecraft to reach that speed and similarly how long will it take to slow down when you are approaching a target planet?
If only wormholes stopped being "theoretical structures"
Haven't you heard? Wormholes are tired, Alcubierre drives is where it's at nowadays. All we need now is a way to shovel away that pesky dark matter.
Oh, that problem has been solved.
Haven't you heard? Dark matter doesn't exist [1]
Off to the stars!
[1] https://scitechdaily.com/dark-matter-may-not-exist-these-phy...
Haven't you heard? Dark matter doesn't exist [1]
Off to the stars!
[1] https://scitechdaily.com/dark-matter-may-not-exist-these-phy...
[deleted]
It's really hard to imagine earthlike planet without vegetation. Deserts would look the same. But how would temperate zone look with soil and rocks and streams and lakes but zero plants.
> Deserts would look the same.
I don't think this is 100% the case. Most deserts on Earth actually have a relatively large variety of life in them -- even the most desiccated deserts will often have at least bacteria of some sort living in them.
I don't think this is 100% the case. Most deserts on Earth actually have a relatively large variety of life in them -- even the most desiccated deserts will often have at least bacteria of some sort living in them.
So, they would basically look the same when looking at them through my space suit helmet.
36% larger radius than Earth means ~2.5x more volume. If it has a similar density to Earth 2.5g would probably stretch the definition of habitable for humans. This doesn't rule out habitation by other life, of course.
Cool that we're finding interesting planets though! An actually human-habitable planet would, I think, have a significant cultural impact here on Earth.
Cool that we're finding interesting planets though! An actually human-habitable planet would, I think, have a significant cultural impact here on Earth.
> 36% larger radius than Earth means ~2.5x more volume. If it has a similar density to Earth 2.5g would probably stretch the definition of habitable for humans.
Volume scales cubically, yes. And therefore, also does the gravitational pull by the object at the same distance to the center. But due to the larger radius, you are also further away. Gravity respects the inverse square law. This means that the surface gravity of an object that maintains the same density increases linearly with the object's size.
In other words, you would have 1.36g on the planet's surface, not 2.5g. But that's assuming same density. Even within our own solar system this is not true: Mars's surface gravity is 0.38 of earth's gravity but 0.53 of earth's radius. The gravity is lower than it would be if Mars had the same density as earth.
Volume scales cubically, yes. And therefore, also does the gravitational pull by the object at the same distance to the center. But due to the larger radius, you are also further away. Gravity respects the inverse square law. This means that the surface gravity of an object that maintains the same density increases linearly with the object's size.
In other words, you would have 1.36g on the planet's surface, not 2.5g. But that's assuming same density. Even within our own solar system this is not true: Mars's surface gravity is 0.38 of earth's gravity but 0.53 of earth's radius. The gravity is lower than it would be if Mars had the same density as earth.
It actually gets you 1.36g, given the same density (your assumption) and using the fact that you are further away from the center of mass you get
g ~ density x radius [0]
[0] https://en.wikipedia.org/wiki/Gravity_of_Earth#Depth
g ~ density x radius [0]
[0] https://en.wikipedia.org/wiki/Gravity_of_Earth#Depth
2.5g means you weigh 2.5 times as much. So if you're 150lbs on Earth that means you'd weigh 375lbs on this new planet. Weighing 375lbs is certainly inconvenient, but it's not like habitation at 375lbs is impossible, especially if you have a scooter.
I wonder what happens if a human child grows up in a 2.5g environment. I imagine they grow up to be short, stocky, and extremely muscular.
Adaptation probably plays a big role here. If you give a 150lb person a suit that weighs 225 lbs and tell them to wear it all the time, they probably give up after a few days. But if you tell a 150lb person to eat more until they're 375lbs, their body has time to adapt.
Since the new planet is 100 light years away, even at the speed of light we're talking about a 100-year journey minimum. Maybe the generation ship used to make the journey could use artificial gravity to smoothly transition from 1g to 2.5g over the course of 100 years. Loading the ship with people who are stocky & muscular is another option.
I don't think living in enhanced gravity needs to be terrible. Astronauts have to exercise more in order to maintain fitness in low-gravity environments. It appears to follow that if you're living in an enhanced-gravity environment, you can get away with exercising a lot less and still maintain fitness :-)
I wonder what happens if a human child grows up in a 2.5g environment. I imagine they grow up to be short, stocky, and extremely muscular.
Adaptation probably plays a big role here. If you give a 150lb person a suit that weighs 225 lbs and tell them to wear it all the time, they probably give up after a few days. But if you tell a 150lb person to eat more until they're 375lbs, their body has time to adapt.
Since the new planet is 100 light years away, even at the speed of light we're talking about a 100-year journey minimum. Maybe the generation ship used to make the journey could use artificial gravity to smoothly transition from 1g to 2.5g over the course of 100 years. Loading the ship with people who are stocky & muscular is another option.
I don't think living in enhanced gravity needs to be terrible. Astronauts have to exercise more in order to maintain fitness in low-gravity environments. It appears to follow that if you're living in an enhanced-gravity environment, you can get away with exercising a lot less and still maintain fitness :-)
More importantly, this sounds like planets tidally locked around a red dwarf.
Red dwarfs are known for flares that would destroy the atmosphere of any nearby planet.
"Although this planet orbits very close to its star, at a distance about 10 times shorter than that of Mercury around our Sun, the amount of stellar irradiation it receives is still low... the star LP 890-9 is about 6.5 times smaller than the Sun and has a surface temperature half that of our star."
Red dwarfs are known for flares that would destroy the atmosphere of any nearby planet.
"Although this planet orbits very close to its star, at a distance about 10 times shorter than that of Mercury around our Sun, the amount of stellar irradiation it receives is still low... the star LP 890-9 is about 6.5 times smaller than the Sun and has a surface temperature half that of our star."
In any case all its water would be locked up in ice on the night side.
If only we could invent a method to turn ice into water..
Needs heat. But that is all found thousands of km away.
Just use mirrors strategically placed so that light can bounce around the horizon so solar can be used to melt the ice. Or orbit a giant mirror beaming that heat source down. The fact that you think thousands of km away is a hard limit just means you're not fully caffinated just yet.
If you are in orbit, why land on it at all? Surely there are construction materials and ice only light-minutes away and not so deep down a gravity well. God knows there is nothing else down there of any interest.
> More importantly, this sounds like planets tidally locked around a red dwarf.
Live on the other side? or a narrow habitable band between the 2 hemispheres
Live on the other side? or a narrow habitable band between the 2 hemispheres
With exactly zero liquid water available? Not likely.
I mean tidally-locked planets/moons in general. Both hemispheres would usually be extremes, but maybe with a “sweet spot” in between.
Only if your "sweet spot" has the sun always right at the horizon, and you don't mind mining all your water from the stuff frozen on the night side.
You could pick a planet where the noonday sun is not too hot, but then the ice would be even further away.
Noplace on Earth is so dry that people are tempted to collect ice from Antarctica, even with shipping today cheaper than it has ever been.
You could pick a planet where the noonday sun is not too hot, but then the ice would be even further away.
Noplace on Earth is so dry that people are tempted to collect ice from Antarctica, even with shipping today cheaper than it has ever been.
Assuming organisms adapted to live there, it would be harder for them to reach escape velocity to leave their planet. Is there a cut-off where known physics says it’s impractical to leave a planet? Ie the most powerful practical fuel wouldn’t be enough for any mass to reach escape velocity?
https://space.stackexchange.com/questions/14383/how-much-big...
There's a table in that link of how much reaction mass is needed to reach orbit. At 1.5g it requires about 500% as much rocket as Earth. At 2.5g the number is ... much larger.
There's a table in that link of how much reaction mass is needed to reach orbit. At 1.5g it requires about 500% as much rocket as Earth. At 2.5g the number is ... much larger.
What evolutionary changes would human beings need to adapt to 2.5g?
Id's say a stronger circulatory sistem.
Muscles and bone density will need to increase, but we do that as part of adaptation, evolution will favor the trait long term but regular use will already compensate in part or totally the need.
Possibly ankles and knees will need to get stronger as well
Muscles and bone density will need to increase, but we do that as part of adaptation, evolution will favor the trait long term but regular use will already compensate in part or totally the need.
Possibly ankles and knees will need to get stronger as well
We would only be adapting to 1.36g according to mamikonyana - this sounds more plausible. Because gravity is a function of size, mass and density. Not only mass.
It might be more feasible to remove a big chunk of matter from the planet in question
Thicker legs
same density, higher size does not mean 2.5 g.
Only some of that mass is below you. Some is to the front, right, back, left, where vectors in sum are zero.
Also, all the "extra" mass is further away from you, and gravitation is proprtional to distance cubed. Interesting.
Apparently surface gravity is proportional to mass/radius^2 [0]
Assuming constant density as per the grandparent, the mass increases with the cube of the radius.
Which simplifies to surface gravity being proportional to the radius of the planet.
[0] https://en.m.wikipedia.org/wiki/Surface_gravity
Apparently surface gravity is proportional to mass/radius^2 [0]
Assuming constant density as per the grandparent, the mass increases with the cube of the radius.
Which simplifies to surface gravity being proportional to the radius of the planet.
[0] https://en.m.wikipedia.org/wiki/Surface_gravity
This is incorrect, the decrease comes from being at a higher altitude from the center of the planet, see gauss' law for gravity. If you kept the altitude the same the force would be exactly proportional as expected.
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> completes an orbit around the star in just 2.7 days
I wonder if you feel centrifugal force spinning that fast around a sun?
I wonder if you feel centrifugal force spinning that fast around a sun?
The equator of the Earth is spinning much faster, on a much tighter radius. Do you "feel centrifugal force" when standing there?
It does actually affect your weight a bit, but if you mean what I think you mean that it would be something you perceptibly feel, it is not.
Moreover, this merely shows that the idea that the magnitude is significant isn't a good one. Even more importantly, you don't "feel" anything in an orbit ever, because when you're on a geodesic, you're in "zero g". You never "feel" anything in an orbit, no matter how fast it is. People on the ISS don't "feel centrifugal force", because they're in zero G.
(Except tides, if you're large enough, but a single person in this orbit is nowhere near large enough or sensitive enough to feel any tides.)
It does actually affect your weight a bit, but if you mean what I think you mean that it would be something you perceptibly feel, it is not.
Moreover, this merely shows that the idea that the magnitude is significant isn't a good one. Even more importantly, you don't "feel" anything in an orbit ever, because when you're on a geodesic, you're in "zero g". You never "feel" anything in an orbit, no matter how fast it is. People on the ISS don't "feel centrifugal force", because they're in zero G.
(Except tides, if you're large enough, but a single person in this orbit is nowhere near large enough or sensitive enough to feel any tides.)
> The equator of the Earth is spinning much faster, on a much tighter radius.
Centrifugal force is proportional to the radius, so a smaller radius actually decreases it, for the same angular velocity. The reason we associate smaller radiuses with increased force is actually because if the energy stays the same, reducing the radius increases the angular velocity (like in a pirouette), which then “feels” like a stronger force.
Centrifugal force is proportional to the radius, so a smaller radius actually decreases it, for the same angular velocity. The reason we associate smaller radiuses with increased force is actually because if the energy stays the same, reducing the radius increases the angular velocity (like in a pirouette), which then “feels” like a stronger force.
Isn't parent star flare star stripping atmosphere from any planet in habitable zone?
Amazing. Fantastic research continually coming out of ESO. Had the opportunity to chat with someone involved (not on this project). Super talented.
Wondering what the follow up opportunities to study this more are coming up.
Wondering what the follow up opportunities to study this more are coming up.
Planet-finding is (understandably) restricted to very extreme types of planets, those which influence their host star in a detectable manner. Certainly cool but I doubt the usefulness.
Does this or other discoveries give us any better estimates for terms in the Drake equation?
Phew! Found a new one just in time.
speculoo 2: electric boogaloo
They named their project, and thus this object, after the popular Belgian¹ speculoos cookie and backronymed it. I'm not sure how I feel about that. I don't dislike names with some pop culture basis, or even better, old sci-fi (given that there a more of those objects than we can dream up names for). On the other hand, naming it after a cookie seems frivolous.
1: Known as speculaas in Dutch.
1: Known as speculaas in Dutch.
Well, they've already rounded that corner a while ago with TRAPPIST:
> TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) is a project led by the Origins in Cosmology and Astrophysics group (OrCA) of the Department of Astrophysics, Geophysics and Oceanography (AGO) of the STAR Institute of the University of Liège (Belgium).
https://www.trappist.uliege.be/cms/c_5006023/en/trappist
> TRAPPIST (TRAnsiting Planets and PlanetesImals Small Telescope) is a project led by the Origins in Cosmology and Astrophysics group (OrCA) of the Department of Astrophysics, Geophysics and Oceanography (AGO) of the STAR Institute of the University of Liège (Belgium).
https://www.trappist.uliege.be/cms/c_5006023/en/trappist
Speculaas and Speculoos are somewhat different things. Speculaas is older and has more spices, apparently.
Another project from the same university is TRAPPIST. Named after Trappist beers.
https://en.wikipedia.org/wiki/TRAPPIST
https://en.wikipedia.org/wiki/Trappist_beer
https://en.wikipedia.org/wiki/TRAPPIST
https://en.wikipedia.org/wiki/Trappist_beer
Don't worry, it will soon be integrated in Stellaris like the TRAPPIST one, so it will become pop culture/sci-fi
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I don't see how pop culture is a-okay as a naming scheme but this lekker cookie isn't. It is in fact pop-culture in its own way.
Sci-fi names tend to be tiresomely similar since they overuse gods names and anglocentric concepts
Sci-fi names tend to be tiresomely similar since they overuse gods names and anglocentric concepts
I like silly backronyms like that[0].
[0] https://en.wikipedia.org/wiki/Speculoos