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Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

arxiv.org

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Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#101

Post by marginalia_nu »

moloch-hai wrote: post #100
marginalia_nu wrote: post #97

Earlier quoted context omitted.

> Mercury is literally the only body in the whole solar system in any sort of more complicated "lock". So, no, it really is about word games. How would you even begin to demonstrate this is true? There are so many bodies in the solar system, and we're still fairly frequently discovering new minor planet moon-systems..

Find another. It would not change anything.

Dunno man. It's very hard to draw statistical inferences based on a solar stellar system. It would even require significant motivation to argue that the measurements are independent.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#102

Post by moloch-hai »

maxamillion2020 wrote: post #74
moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

Yes, but our planet detecting tools can only currently detect planets that are 1. close to their stars and 2. smallish, so that self-selects for tidally locked planets.

As I said.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#103

Post by [deleted] »

moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

[deleted]

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#104

Post by moloch-hai »

rich_sasha wrote: post #92
moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

I was reading about "eyeball planets", which are possibly suitable for life, and match this description (vaguely, IANAAstrophysicist). Basically, the idea is that a planet of right size and roughly in the right distance to its star is tidally locked in a 1:1 resonance, so one side is always pointing at the star, and one always poiting away. Now, the perpetual noon point is very hot, and the perpetual midnight point i…

The water remains frozen on the dark side. Maybe there is so much water that enough sublimates to rain out at the terminator? Still, it is poor pickings.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#105

Post by moloch-hai »

marginalia_nu wrote: post #101
moloch-hai wrote: post #100

Earlier quoted context omitted.

Find another. It would not change anything.

Dunno man. It's very hard to draw statistical inferences based on a solar stellar system. It would even require significant motivation to argue that the measurements are independent.

The topic here is the word game defrost and now you promote. Does "tidal lock", absent further detail, imply 1:1? Yes.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#106

Post by koheripbal »

rich_sasha wrote: post #92
moloch-hai wrote: post #40

None of these "habitable" planets is really plausibly habitable. In particular, orbiting so close, they are all tidally locked 1:1 to their star, presenting always the same face. If they have any water, it is frozen on the dark side. But they might have no water anyway because they (might!) have no magnetic field to fend off the solar wind that would take away all their hydrogen, as happened to Venus. Earth has its b…

I was reading about "eyeball planets", which are possibly suitable for life, and match this description (vaguely, IANAAstrophysicist). Basically, the idea is that a planet of right size and roughly in the right distance to its star is tidally locked in a 1:1 resonance, so one side is always pointing at the star, and one always poiting away. Now, the perpetual noon point is very hot, and the perpetual midnight point i…

The problem is that over time the atmosphere would vaporize into space from the hot side so you will get a barren rock like Mercury.

There's always a liiiiitle rotation, so even any frozen gases on the cold side would eventually rotate into the sun and be heated to escape velocity.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#107

Post by marginalia_nu »

moloch-hai wrote: post #105
marginalia_nu wrote: post #101

Earlier quoted context omitted.

Dunno man. It's very hard to draw statistical inferences based on a solar stellar system. It would even require significant motivation to argue that the measurements are independent.

The topic here is the word game defrost and now you promote. Does "tidal lock", absent further detail, imply 1:1? Yes.

The meaning of a word is conventional.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#108

Post by moloch-hai »

koheripbal wrote: post #106
rich_sasha wrote: post #92

Earlier quoted context omitted.

I was reading about "eyeball planets", which are possibly suitable for life, and match this description (vaguely, IANAAstrophysicist). Basically, the idea is that a planet of right size and roughly in the right distance to its star is tidally locked in a 1:1 resonance, so one side is always pointing at the star, and one always poiting away. Now, the perpetual noon point is very hot, and the perpetual midnight point i…

The problem is that over time the atmosphere would vaporize into space from the hot side so you will get a barren rock like Mercury. There's always a liiiiitle rotation, so even any frozen gases on the cold side would eventually rotate into the sun and be heated to escape velocity.

There is always a little sublimation, anyway.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#109

Post by moloch-hai »

marginalia_nu wrote: post #107
moloch-hai wrote: post #105

Earlier quoted context omitted.

The topic here is the word game defrost and now you promote. Does "tidal lock", absent further detail, imply 1:1? Yes.

The meaning of a word is conventional.

And of exactly zero interest.

The original topic, so cleverly but pointlessly derailed, was the viability of planets we can just barely detect in extremely close orbit around a dim star, in 1:1 tidal lock, with permanently hot and a cold sides, and, likely, no magnetic field. That merited discussion.

Re: Wolf 1069B: Earth-mass planet in the habitable zone of a nearby, low-mass star

#110

Post by Dylan16807 »

moloch-hai wrote: post #70
Dylan16807 wrote: post #67

Earlier quoted context omitted.

It's not about word games, it's about how high the prevalence of 1:1 locking is. Especially when you use words like "all" and "can't spot". Looking at the moons in our solar system is evidence but not definitive.

Looking at the hundreds of moons defines "locked" without qualification to imply 1:1. Mercury is literally the only body in the whole solar system in any sort of more complicated "lock". So, no, it really is about word games.

If you don't care about "word games", I suggest you stop arguing about "locked" and focus on the actual point, which I rephrased for you. The actual point is about prevalence.

> hundreds of moons

> literally the only body

They are all moons, not planets, and not in different star systems. That's not enough to make conclusive statements about exoplanet spin.

That statistic is more relevant to the word games but I'm not here for word games either. It doesn't matter if "lock" implies 1:1.

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