Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Extreme supersonic winds measured on a planet outside our solar system

phys.org

Post reply on HN
Print view View original

41–50 of 63 posts

Re: Extreme supersonic winds measured on a planet outside our solar system

#41

Post by asdff »

ZaoLahma wrote: post #19
davedx wrote: post #17

Earlier quoted context omitted.

But there are also 7500 known exoplanets within a few tens of thousands of light years of Earth. There are almost certainly multiples more than that we cannot see. The "Goldilocks Zone" is also highly anthropomorphised: there are extremophiles that live in all sorts of crazy environments on Earth. I'm coming around to the Dark Forest theory, personally, as terrifying as it is.

> I'm coming around to the Dark Forest theory, personally, as terrifying as it is. If you're silent with the intent of remaining hidden, then that behavior must have been learned. Either you evolved from a prey type of species, or a non-apex predator. It would be strange of humanity is the only apex-ish predator intelligent-ish life form in the universe that blasts signals into space without consideration of who migh…

No it is not necesarily learned. Even among species on earth a lot of behaviors are not learned but inherent. In other words, selection acts on a spectrum of behaviors and those with some fitness advantage you are likely to see more frequently in the next generation of offspring, extending until lineages of that offspring with that behavior are potentially all there is.

A dark forest planet need not learn to be a dark forest planet in the same way an earth colored beetle need not learn to perfectly mask itself against the dirt from a bird; the fitter mutation given the context of the environment won out.

Re: Extreme supersonic winds measured on a planet outside our solar system

#42

Post by asdff »

thrance wrote: post #22
davedx wrote: post #17

Earlier quoted context omitted.

But there are also 7500 known exoplanets within a few tens of thousands of light years of Earth. There are almost certainly multiples more than that we cannot see. The "Goldilocks Zone" is also highly anthropomorphised: there are extremophiles that live in all sorts of crazy environments on Earth. I'm coming around to the Dark Forest theory, personally, as terrifying as it is.

IMO the dark forest hypothesis leads to fun books but makes little sense. If a civilization is capable of the unimaginable feat of interstellar travel, surely their basic needs are well met and they aren't driven by base animal instincts anymore. They can probably engineer their own psyche. We humans will soon hit a population peak too, no exponental growth on the horizon. Also, I don't think the timescales make sens…

That is if you assume the aliens will board a ship with conventional forces and enact a human style invasion.

Now what if the alien was not even sentient. A giant configuration of some structure of chemistry just floating through interstellar space, catalyzing reactions when inputs are met, lying in wait otherwise. It might not “die” in the sense that any other mass of atoms doesn’t “die.” When faced with some input it might swell up in size, divide and diffuse elsewhere. Akin more to a random chemical interaction among a few molecules in pure solvent than life as we know it.

Chemical structures like this could potentially be the wildfire patrolling the universe for fuel vs some spacefaring roman empire.

Re: Extreme supersonic winds measured on a planet outside our solar system

#43

Post by krick »

I don't understand. How can wind be supersonic? Isn't wind essentially a super-low frequency sound? Well, ok, not exactly, but still, it moves pretty much like sound. For it to be supersonic, air mass behind needs to move faster, than air mass in the front of it can be pushed, which seems kinda self-inconsistent. It doesn't make any sense.

Re: Extreme supersonic winds measured on a planet outside our solar system

#44

Post by jajko »

Earw0rm wrote: post #8

Not an original thought, but I wonder if the answer - or part of it - to the Fermi paradox is that we don't know all the ways it's possible for a planet in the Goldilocks Zone to be otherwise hostile to life. Liquid water and.. chemistry leading to an ambient pH of 2 or 12. Liquid water and.. radiation environment such that proto-RNA strands get immediately smashed to bits by high-energy rays. Liquid water and.. bomb…

Things can hide in bigger depths with little to worry how surface of some massive ocean behaves.

There are proper life filters but this isnt one of them. Folks just have to stop looking at survival and evolution in terms of 'if we dont have this pleasant spring stable situation life is doomed and has no chance'.

Challenge breeds adaptation, thats how our ancestors made it, environment was brutal and extremely hostile. Didnt matter, not for us at least.

Re: Extreme supersonic winds measured on a planet outside our solar system

#45

Post by Evidlo »

krick wrote: post #43

I don't understand. How can wind be supersonic? Isn't wind essentially a super-low frequency sound? Well, ok, not exactly, but still, it moves pretty much like sound. For it to be supersonic, air mass behind needs to move faster, than air mass in the front of it can be pushed, which seems kinda self-inconsistent. It doesn't make any sense.

The speed of sound on earth at sea level

Re: Extreme supersonic winds measured on a planet outside our solar system

#46

Post by dbspin »

semi-extrinsic wrote: post #39
RandomBacon wrote: post #33

Earlier quoted context omitted.

> I'm coming around to the Dark Forest theory, personally, as terrifying as it is. Perhaps it's just that advanced technology is extremely rare given another comment's supposition that there could be other intelligent life, just unable to make advanced technology, or along those lines: if they have the appendages to do so, maybe their environment doesn't have the resources. If you couple the above with the idea that…

> the idea that FTL communication/travel is difficult or impossible Not just FTL. My hypothesis is that any type of substantial interstellar travel is going to be so enormously expensive, complicated and time consuming, an advanced civilisation will only do it once in a billion years. In the form of mass exodus when there are no more habitable planets in their system or their star is going nova. As this never gives e…

But that's simply not the case. We likely very close to the technology needed to get tiny objects to a decent fraction of lightspeed using laser arrays. Assuming genuine AGI is possible and miniaturisation continues, there's no physical reason a digital intelligence couldn't rapidly (on interstellar time scales) colonise the galaxy.

Source - https://breakthroughinitiatives.org/initiative/3

Re: Extreme supersonic winds measured on a planet outside our solar system

#47

Post by octubre »

krick wrote: post #43

I don't understand. How can wind be supersonic? Isn't wind essentially a super-low frequency sound? Well, ok, not exactly, but still, it moves pretty much like sound. For it to be supersonic, air mass behind needs to move faster, than air mass in the front of it can be pushed, which seems kinda self-inconsistent. It doesn't make any sense.

I think wind is not like a sound, it's the bulk movement of the air itself instead of the propagation of a pressure wave (where there could be no average bulk movement). That's why wind can be different speeds and sounds are always the same speed (in the same air...)

Re: Extreme supersonic winds measured on a planet outside our solar system

#48

Post by thrance »

asdff wrote: post #42
thrance wrote: post #22

Earlier quoted context omitted.

IMO the dark forest hypothesis leads to fun books but makes little sense. If a civilization is capable of the unimaginable feat of interstellar travel, surely their basic needs are well met and they aren't driven by base animal instincts anymore. They can probably engineer their own psyche. We humans will soon hit a population peak too, no exponental growth on the horizon. Also, I don't think the timescales make sens…

That is if you assume the aliens will board a ship with conventional forces and enact a human style invasion. Now what if the alien was not even sentient. A giant configuration of some structure of chemistry just floating through interstellar space, catalyzing reactions when inputs are met, lying in wait otherwise. It might not “die” in the sense that any other mass of atoms doesn’t “die.” When faced with some input…

One might argue encountering something like this would be more akin to a natural catastrophe (like a killer meteor) rather than an alien invasion.

Stephen Baxter wrote a novel in which galaxies would be regularly wiped out by a natural phenomena, and that explains why there are no aliens in his universe. It's "Manifold: Space" if you're interested.

Re: Extreme supersonic winds measured on a planet outside our solar system

#49

Post by chasil »

davedx wrote: post #17
Earw0rm wrote: post #8

Not an original thought, but I wonder if the answer - or part of it - to the Fermi paradox is that we don't know all the ways it's possible for a planet in the Goldilocks Zone to be otherwise hostile to life. Liquid water and.. chemistry leading to an ambient pH of 2 or 12. Liquid water and.. radiation environment such that proto-RNA strands get immediately smashed to bits by high-energy rays. Liquid water and.. bomb…

But there are also 7500 known exoplanets within a few tens of thousands of light years of Earth. There are almost certainly multiples more than that we cannot see. The "Goldilocks Zone" is also highly anthropomorphised: there are extremophiles that live in all sorts of crazy environments on Earth. I'm coming around to the Dark Forest theory, personally, as terrifying as it is.

The oxygen in our atmosphere has been prominent for millions of years, highly visible.

Anyone who is curious is already here, or has been here.

Re: Extreme supersonic winds measured on a planet outside our solar system

#50

Post by ridgeguy »

metalman wrote: post #23

there is a good chance that the "measurement" is recording some other phenominon, as this can only be an interpretation of albedo changes, and could be the signal from say, low orbiting small moons or a planetary ring,atmospheric electrical discharges in any case, it is most definitly not an actual wind speed measurement, plus strictly speaking "wind" can only happen in air, and this, again, can only be something els…

This isn't measurement of albedo changes. It's measurements of spectra that exhibit Doppler effect, which permits measurement of wind velocity. From the abstract:

"We studied the transmission spectrum of the hot Jupiter WASP-127 b during one transit in the K band with CRIRES+."

They acquired spectra for H2O and CO with hi-res transmission spectroscopy as the planet transited its star.

https://www.aanda.org/articles/aa/full_html/2025/01/aa50438-...

Post reply on HN