anindefinitearticle
@anindefinitearticle@sh.itjust.works
I firmly believe that a “crustless ice mantle” meets the definition of an ocean.
- Comment on Anon gets rid of crackheads 5 days ago:
That’s why you befriend them instead of scaring them away.
Until the fact that you befriended them gets you fired because it scares your coworkers.
- Comment on Checking in 1 week ago:
- Comment on Water 2 weeks ago:
The planet definition that excluded pluto was decided upon at the end of an IAU conference after most planetary scientists had left. As a result, only dynamicists are happy with it. Planetary geologists in particular HATE it and have always vocally pushed back.
- Comment on Water 2 weeks ago:
And if you want more, check out what I said last time this meme was posted.
As someone who worked as an astrophysicist for 9 years, I assure you that the question of “what is a planet?” is a nuanced discussion with a lot of diverse opinions and no clear answer that gets endlessly debated by students as they learn that these definitions aren’t as cut and dry as irresponsible science communicators made it seem during the disastrous and highly politically motivated demotion of Pluto to dwarf planet.
- Comment on Water 2 weeks ago:
IAU is well known for coming up with shitty arbitrary classifications about nomenclature that many astronomers don’t agree with. They are wrong here because they don’t take into account post-Cassini/Juno understanding of gas giant morphology. The IAU definition is outdated and highly misleading.
Copied from another reply I gave in this thread:
I’ve seen 13 MJ argued as a boundary, but it’s selected somewhat arbitrarily and based around idealized models of Deuterium fusion, which has never been observed, and which is a process these brown dwarves would only undergo for a brief flash in their early life. Deuterium isn’t abundant enough for its fusion to significantly alter the stellar morphology that has already become established for objects larger than Saturn. Saturn is our solarsystem’s example of an object that does not fit cleanly into one side or the other of a mass-based binary classification scheme for determining a hard boundary between “planet” and “star”. To understand what is a planet vs what is a star, study Saturn.
- Comment on Water 2 weeks ago:
Based on what criteria?
Jupiter is large enough for the hydrogen to become a plasma and dissolve the rocky “planetary” core that was once at the center. Morphologically, it has passed the transition from planet to star. Saturn appears to be somewhere along that transition and is harder to cleanly classify.
Morphologically, Jupiter is a star.
I’ve seen 13 MJ argued as a boundary, but it’s selected somewhat arbitrarily and based around idealized models of Deuterium fusion, which has never been observed, and which is a process these brown dwarves would only undergo for a brief flash in their early life. Deuterium isn’t abundant enough for its fusion to significantly alter the stellar morphology that has already become established for objects larger than Saturn. Saturn is our solarsystem’s example of an object that does not fit cleanly into one side or the other of a mass-based binary classification scheme for determining a hard boundary between “planet” and “star”. To understand what is a planet vs what is a star, study Saturn.
- Comment on Water 2 weeks ago:
It’s a Y-class brown dwarf star. Saturn likely is as well.
- Comment on Water 2 weeks ago:
Obligatory “what about Jupiter”
- Comment on Water 2 weeks ago:
You’re comparing them linearly, a comparison for which the statement is false.
The statement is true multiplicatively/logarithmically/unitarily.
Atomic radius is ~ 1e-10m
Light second is ~3e8m
As a ratio, your height can be measured as 1.8e10 atomic radii, and a light second can be measured using only 1.7e8 humans who are 1.8m tall.
Does that help?
- Comment on Anon goes to therapy 2 weeks ago:
Bad habit from middle school when we used “therapist.com” as bait for overzealous admins trying to crack down on internet use.
- Comment on Anon goes to therapy 2 weeks ago:
The whole “similarity of life experience” bit is the hard part if you’re an outsider without much in common with the liberal elites that make up the vast majority of the rapists.
It’s really not a surprise that the rapy is recommended pretty exclusively by people from the same demographic group as the rapists, nor that people who get excluded from the highly exclusionary and non-diverse liberal society tend to strongly dislike the profession.
- Comment on Anon's in trouble 3 weeks ago:
The atmosphere is big and heavy. Small pressure changes on order 1% means hurricane. 50% of an atmosphere pushing on something is a lot.
Note, this is all Earth’s atmosphere.
Titan’s atmosphere is energy-denser than ours at 1.5 atm. Titan is Saturn’s largest moon.
Venus has 96 atm. Absolutely crushing and hard to visit at all.
Mars varies from like 0.3-0.6% seasonally as significant portions of its CO2 atmosphere deposit onto the poles as dry ice glaciers in a runaway greenhouse style. CO2 snows out, temps drop, more snows. Keeps going till the sun comes back. Sunlight sublimates the ice back into the atmosphere in a similar runaway fashion. Like a deep breath in and out with the seasons. The weight of all that ice falling and leaving keeps that red lump beating every year. Don’t believe those who say Mars is dead. We don’t know yet. Don’t count out anything with a breath and a beat. What is life on a planetary scale, anyhow?
The gas giants have atmospheric pressures so high it kind of stops making sense to use these as comparisons, and instead we have to look to geology for analogues as deep within the earth we also approach these energy densities.
- Comment on Anon's in trouble 3 weeks ago:
Let’s convert to metric so we can tell.
15 ft is about 5 m.
Water pressure increases by 10,000 pa per meter (rhogh, rho=1000 kg/m^3, g~10m/s^2), so total pressure is 50 kpa, or 1/2 earth atmospheric pressure.
One side of that hole has ambient pressure of 1 atm. The other side has that plus water pressure totalling 1.5 atm.
A pressure is just an energy density. Multiply by the cross-sectional area of the interface to get the energy gradient across the interface. An energy gradient is a force. We don’t have a measure of the cross-sectional area of the hole, but if we expect a person to fit through let’s call it 1m^2.
50 kpa = 50 kJ/m^3, so total force felt across this opening is 50kN which is the equivalent weight of five metric tons.
I’d say this person is going to have a bad time with five metric tons pushing them towards that little hole.
- Comment on Pro-tip for this capitalistic hellscape 1 month ago:
That’s not carbs, that’s water weight.
Look at the source again, at the pie chart of “calories by source”. 80% protein, 16% carbs, 4% fat.
- Comment on I'm sure everyone remembers 1 month ago:
I read that there would be genetic markers of a manmade virus, and that this virus’s RNA matched a natural evolution.
Every action leaves some sort of trace.
- Comment on I'm sure everyone remembers 1 month ago:
Curious to know what you mean here.
What parts of a virus could they find to be racist about?
- Comment on So this is how liberty dies... 2 months ago:
What’s he gunna do with Cheney’s bunker under 1 Observatory?
He can spy on everyone’s couches at once!
- Comment on Science fact 3 months ago:
It absolutely depends on the context.
- Comment on Science fact 3 months ago:
They are!
Electromagnetically and gravitationally and chemically they act like stars.
Gas giant simulations are often performed by stellar codes such as mesa. Stellar physics and stellar simulations with fusion turned off. Morphologically, they are stars. We should move on from the cold war brain’s fusion chauvinism.
They are fundamentally different objects than planets. They have their own planetary systems. They’re stars, just unlit.
Juno gravity results imply Jupiter’s core is dissolved hydrogen plasma sludge, also known as the dilute core model. Kronoseismology (using saturn’s rings as a seismograph; Cassini read it like a DVD) implies the same is likely true for Saturn due to the discovery of g-mode waves mixing with the f-mode signal detected by ring occultations.
- Comment on Science fact 3 months ago:
Yes.
Y dwarf stars are a mix of what was previously classified under those mass classifications.
- Comment on Science fact 3 months ago:
dated 1997
Here they are on Wikipedia’s list of Y-class brown dwarves.
Jupiter and Saturn are in fact brown dwarves.
Stellar classes are OBAFGKMLTY, from most to least massive.
- Comment on Science fact 3 months ago:
Jupiter and Saturn are brown dwarves, and fit many definitions of “star”.
They are both large enough to have developed a hydrogen plasma core furnace that dissolves the rock and ice that was once their core. They are more than just a hydrogen atmosphere, down to the core they’re a big ball of plasma undergoing all of the same physics as stellar tissue, except the pressure at the center isn’t enough to ignite fusion.
Uranus and Neptune, meanwhile, are likely too small for this, and maintain a fluid ice layer and rocky core beneath their hydrogen envelopes. There is not enough hydrogen for it to take over these worlds. Therefore, they are planets, not brown dwarf stars.
Jupiter and Saturn, however, have grown large enough for the hydrogen to have turned to plasma and dissolved and supplanted their cores with a plasma furnace.
The solar system has three stars. We are not too early to explore other star systems. We know of many planets around Jupiter and Saturn. The extraterrestrial planet with most earth-like atmosphere and surface geology that we know of is Titan, and it’s in our neighboring (sub) star system. Huygens and Juice and Europa Clipper and Dragonfly are humanity’s first missions to planets around other stars.
- Comment on Gender 3 months ago:
No factory default due to data corruption, so I uninstalled it as bloat. Then I wrote a few of my own to play with, but instead of dynamically assigning at boot I set up hotswapping.
- Comment on 13 years ago, indicted New York City Mayor Eric Adams made a weird as hell video about searching your teenager's room for drugs and guns. 3 months ago:
It’s the fourth amendment, Eric, not the first.
- Comment on Mafs innit 3 months ago:
Is that what they call an upside-down cake?
- Comment on Rules 3 months ago:
Replace “makes” with “is correlated with” because we don’t have sufficient evidence to infer causality.
- Comment on Hey nerd 3 months ago:
That word is especially disgusting because we all know Bill Gates chose it so he could name his company after his penis.
- Comment on Lord of the SCIENCE 4 months ago:
No, even without an atmosphere you have to contend with the diffraction-limited resolving power through an aperture (pupil), which is related to the diameter of the aperture and the wavelength of light.
A diffraction process is, mathematically, a fourier transform. A fundamental mathematical feature of a fourier transform is what’s known as the uncertainty principle.
Side note: you’ve probably heard of the special case of an uncertainty principle encountered in quantum mechanics frequently misattributed to the head of the Nazi nuclear program (Heisenberg), but this mathematical principle was actually well known for centuries beforehand, and the misattribution is mostly because of Nazi propaganda. We see it anywhere a fourier transform is used, from optics to orbital dynamics to quantum particles. This mathematical phenomenon is frequently miscited as quantum “weirdness” even though there’s nothing quantum (or all that weird) about it.
The pupil restricts the possible positions of incoming photons. A restriction in position increases the variance of momenta (for a photon, speed never changes, but the momentum vector can still change direction). A smaller pupil is more restrictive and causes the image to be blurrier as the incoming photons from each object you are trying to resolve. If you want to be able to resolve smaller angular sizes (small objects at large distances), you need a large aperture that reduces position restrictions on incoming photons and therefore diffraction-induced blurring due to momentum uncertainties.
Look up Airy diffraction for the special case of a circular aperture (e.g. a pupil or telescope).
- Comment on Is linux actually gaming ready or is it just not for me? 4 months ago:
I searched “gtx 1660 vs amd” and saw that your card is usually compared to the rx 590 from amd on speed tests, with similar results. Price is also similar.
One example that includes the prices I was comparing. I have used neither card. I’m not familiar with that website. Do your own research before making a purchase,
- Comment on Is linux actually gaming ready or is it just not for me? 4 months ago:
What motivated you to switch branches? Did it solve another issue? Why were you not on the latest branch yesterday, ie, why did you roll back originally? Does one driver work better for some games, and another driver works better for others?
Nvidia drivers are jank. I honestly haven’t touched them since 2017. I remember having to reboot and switch drivers to switch games I was playing with friends and finding the whole experience annoying as hell. I realized that Linus Torvalds was right, fuck nvidia, AMD is the way to go. Have not had to touch anything with my drivers since switching. All of my interactions with nvidia since have confirmed that they are not a company deserving of my patronage.
