astronomy

DriftingDeep, rok temu w Neptune and Uranus seen in true colours for first time

InB4 “Uranus seen in true colors for first time.”

Really though, I don’t know why it never crossed my mind that the picture of Neptune was so… saturated. It’ll take a little bit to reconcile this new perspective of a “light bluish-green” Neptune. It’s just so jarring to alter a belief held since my childhood.

clearedtoland, rok temu w Neptune and Uranus seen in true colours for first time

First they take away Pluto and now they’ve come for Neptune! My childhood was a lie.

Xariphon, rok temu w A Bizarre State of Matter Exists Deep Inside Large Neutron Stars

Would it be a yes-or-no thing, or more of a continuum?

At stellar mass x there's Some quark soup but it's mostly ordinary neutronium, at 50x there's More, at 10,000x there's Pretty Much All Of It, etc?

Or is it a critical mass kind of thing where at stellar mass x there's No Soup For You and at x+3 it's a veritable soup buffet?

MartianSands, rok temu

The latter, I suspect. That’s certainly how forming a neutron star works in the first place, because if a star gets so dense that it can form neutronium then the neutronium (which is far more dense than the core was before) can easily keep making more.

It’s a similar story with black holes. Get past the threshold at which it forms, and the process runs away and swallows the whole star.

If a quark soup is more dense than neutronium, then it would be fairly all-or-nothing

elucubra, rok temu w ESA's tiny pinhole thruster is ready for production

Nobody expects the Spanish propulsion

Vqhm, rok temu w Should Astronauts Be Allowed to Eat Each Other If They’re Starving?

Wouldn’t be the first time and prolly won’t be the last time.

Jamestown.

Jamestowne is home to the ruins of the first permanent English settlement in North America.

104 settlers but only 38 survived

Despite writing describing cannibalism:

“Haveinge fedd upon our horses and other beastes as longe as they Lasted, we weare gladd to make shifte with vermin as doggs Catts, Ratts and myce…as to eate Bootes shoes or any other leather,” he wrote. “And now famin beginneinge to Looke gastely and pale in every face, thatt notheinge was Spared to mainteyne Lyfe and to doe those things which seame incredible, as to digge upp deade corpes outt of graves and to eate them. And some have Licked upp the Bloode which hathe fallen from their weake fellowes.”

Direct evidence of cannibalism at Jamestown, the oldest permanent English colony in the Americas was elusive until recently finding “bones in a trash pit, all cut and chopped up, it’s clear that this body was dismembered for consumption.”

smithsonianmag.com/…/starving-settlers-in-jamesto…

LibsEatPoop, rok temu w Should Astronauts Be Allowed to Eat Each Other If They’re Starving?

This is freaking hilarious. I might buy this book just to read more of this:

“Imagine you’re stranded on the Red Planet with three crewmembers,” Seedhouse, a professor at Daytona Beach’s Embry-Riddle Aeronautical University wrote. “You have plenty of life-support consumables but only sufficient food to last one person until the rescue party arrives. What do you do?.. One day, while brewing coffee for breakfast, you realize there are three chunks of protein-packed meat living right next to you.”

… the biggest of the Mars explorers should sacrifice themselves first because they “both consume and provide the most food.” He went on to provide a “weirdly detailed look” at how to cut up one’s fellow humans if necessary.

“We don’t know where Seedhouse would fall in the buffet line because we couldn’t find his height and weight online,” the authors wrote, “and honestly we’re scared to ask.”

In “Survival and Sacrifice”… readers will also find… a photo of ten astronauts smiling in space alongside the caption: “In the wrong circumstances, a spacecraft is a platform full of hungry people surrounded by temptation. Is it wrong to waste such a neatly packaged meal?”

Great marketing.

Artyom, rok temu w Are we living in a baby universe that looks like a black hole to outsiders?

I used to think this idea was kinda silly and based on flimsy and handwavey justification, but then I saw a colloquium by a famous black hole physicist on it. Now I REALLY think this idea is silly and made up!

TauZero, rok temu w Black holes could come in 'perfect pairs' in an ever expanding universe

Oh! They don’t mean that black holes must come in perfect pairs! The headline makes it sound like it’s about wormholes across vast distances. No! What they’ve found is a stable “orbit” solution for the two-body problem. Normally when you place two bodies anywhere in an empty universe, they will gravitate towards each other until they collide. But in a universe with dark energy, there is some perfect distance between them, where the accelerating expansion perfectly counterbalances the accelerating attraction. They’ve used general relativity math to actually calculate such an arrangement.

The “stable” orbit in this case is the same kind of stable as a pencil balanced on its sharp tip - if it tilts even slightly one way it will fall out of control. Although they tantalize the idea that they might be able to make it truly stable against small perturbations once they finish their spinning black hole solution.

I would like to have known some specific numbers examples! Like if you have as much dark energy as our universe, and two 10-solar-masses stellar black holes, how far apart would that be? Is it like 1Ly or 1MLy? How far for two 10-million-solar masses supermassive black holes? The formulas they created should give the exact answer but I am not skilled enough to substitute the correct numbers for the letters.