"Russia to drop out of International Space Station after 2024"
I can't say that is surprising. It's been a nice surprise that we've had international cooperation on it for so long. MIR2 incoming.
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A fascinating summary and overview of the fast and furious science being done with JWST's new data and images
One of JWST’s much-touted abilities is the power to look back in time to the early universe and see some of the first galaxies and stars. Already, the telescope — which launched on Christmas Day 2021 and now sits 1.5 million kilometers from Earth — has spotted the most distant, earliest galaxy known.
Two teams found the galaxy when they separately analyzed JWST observations for the GLASS survey, one of more than 200 science programs scheduled for the telescope’s first year in space. Both teams, one led by Rohan Naidu at the Harvard-Smithsonian Center for Astrophysics in Massachusetts and the other by Marco Castellano at the Astronomical Observatory of Rome, identified two especially remote galaxies in the data: one so far away that JWST detects the light it emitted 400 million years after the Big Bang (a tie with the oldest galaxy ever seen by the Hubble Space Telescope), and the other, dubbed GLASS-z13, seen as it appeared 300 million years after the Big Bang. “It would be the most distant galaxy ever found,” said Castellano.
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Absolutely stunning space photos by Judy Schmidt, thanks to James Webb Telescope data
Credit to Judy Schmidt, an amateur space image processor (that's what BoingBoing called her, which brought her work to my attention.) The post's link is to her Flickr account with this and many more amazing pictures she's created.
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I think I used to know this. But being reminded of it, especially with James Webb giving us amazing images of the depths of space makes it all the more mind blowing.
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Interview with Jane Rigby about scheduling James Webb's workload
“Give me a telescope, and I can come up with something good to do with it,” says Jane Rigby, an astrophysicist at NASA’s Goddard Space Flight Center who serves as the agency’s operations project scientist for the $10-billion James Webb Space Telescope, the largest and most powerful off-world observatory yet built by humankind.
Later in the interview she delves into the need for thrust for the JWTS, which I knew was a thing, but hearing the in-depth answer is absolutely fascinating
Photons striking Webb’s sunshield apply torque. Now, we could orient the sunshield to cancel out the torques—but we want to point the telescope at targets, not get the sunshield perfectly balanced by sunlight. So the photons hit the sunshield, they apply torque, and Webb’s reaction wheels spin up to counteract this effect and keep the telescope pointed. But the reaction wheels can only spin so fast. They occasionally have to dump their angular momentum. In low-Earth orbit, Hubble just couples the reaction wheels to the Earth’s magnetic field to slow them down. That doesn’t work out in deep space, so instead Webb fires thrusters to push against the spin of the reaction wheels. We do these momentum dumps periodically, each time using little propellant. But, as you mentioned, at this stage we have enough propellant to get into the 2040s, so Webb’s longevity is more likely to be limited by how long components last…. Honestly, though, it feels weird to be plotting the nursing-home days of this telescope when it’s still a newborn just opening its eyes!
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Dissolving the Fermi Paradox (2018)
Due to the discussion I dove into around the quantum communication, I was pointed to this 2018 mathametics paper which seeks to disprove the Fermi paradox. Here's their first paragraph of the introduction:
While working at the Los Alamos National Laboratory in 1950, Enrico Fermi famously asked his colleagues: ”Where are they?” He was pointing to a discrepancy that he found puzzling: Given that there are so many stars in our galaxy, even a modest probability of extraterrestrial intelligence (ETI) arising around any given star would imply the emergence of many such civilizations within our galaxy. Further, given modest assumptions about their ability to travel, to modify their environs, or to communicate, we should see evidence of their existence, and yet we do not. This discrepancy has become known as the Fermi paradox, and we shall call the apparent lifelessness of the universe the Fermi observation.
And then from the paper's conclusion, the bracketed segment is my filling in context:
When we update [the Drake equation's point estimates with probability distributions] in light of the Fermi observation, we find a substantial probability that we are alone in our galaxy, and perhaps even in our observable universe (53%–99.6% and 39%–85% respectively). ’Where are they?’ — probably extremely far away, and quite possibly beyond the cosmological horizon and forever unreachable.
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Mathematical calculations show that quantum communication across interstellar space should be possible
The reddit thread for this article notes that this is not breaking the speed of light for communications, instead it is about the distance that could be communicated. Rather than the weakening radio signals, etc.
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Astronomy Is About to Get Way More Exciting Because of the James Webb Telescope
For astronomers, being here on the cusp of a bold new understanding of things is like trying to fall asleep the night before Christmas. (They’re certainly less stressed out than they were on the actual night before Christmas, in 2021, in the hours before Webb launched to space on December 25.)
Next week’s lineup includes an assortment of subjects that are meant to demonstrate Webb’s range as an all-purpose space telescope that can show us the universe in infrared, a wavelength invisible to our eyes.
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There are more galaxies than even Carl Sagan imagined - Big Think
But when it comes to the number of galaxies that are actually out there, we’ve learned a number of important facts that have led us to revise that number upwards, and not just by a little bit. Our most detailed observations of the distant Universe, from the Hubble eXtreme Deep Field, gave us an estimate of 170 billion galaxies. A theoretical calculation from a few years ago — the first to account for galaxies too small, faint, and distant to be seen — put the estimate far higher: at 2 trillion. But even that estimate is too low. There ought to be at least 6 trillion, and perhaps more like 20 trillion, galaxies, if we’re ever able to count them all.
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How Many Decimals of Pi Do We Really Need?
For JPL's highest accuracy calculations, which are for interplanetary navigation, we use 3.141592653589793. Let's look at this a little more closely to understand why we don't use more decimal places.
Up to now, I have only ever memorized 3.14159 as that is plenty accurate for any calculation I might need to do. But knowing that NASA uses just ten more digits is a good motivation that I should memorize that far in case I ever need to calculate space travel.
Give the article a read as it goes into great depth as to why fifteen digits is more than enough for NASA.
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James Webb telescope reaches its final destination, 1 million miles away
What an amazing achievement. I cannot wait to see what it starts to see and what we start to learn from it.
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Is the surface of the sun solid
/u/Solestian asked:
This might seem like a stupid question, perhaps it is. But, let's say that hypothetically, we create a suit that allows us to 'stand' on the sun. Would you even be able to? Would it seem like a solid surface? Would it be more like quicksand, drowning you? Would you pass through the sun, until you are at the center? Is there a point where you would encounter something hard that you as a person would consider ground, whatever material it may be?
/u/VeryLittle gave this excellent answer:
Before anyone goes mocking this question, it's actually very clever. Let me explain.
The sun is fluid, all the way through, even if that fluid is very different than any you might be used to on earth. It's a plasma, meaning that the electrons are separated from the nuclei (though the level of ionization varies with temperature and depth). This traps light, specifically photons, which bounce back and forth between charged particles.
The deeper you go, the denser this plasma gets, as it gets compressed by all the weight on top of it. The outer most layers of the sun that you see, 'the photosphere', is just the part where this plasma has such a low density that photons can escape from it. But it's actually a layer about 300 km thick, because the average distance a photon can travel here before bumping into a charged particle is a few 100 km. This means they escape, shining off into the solar system. This does a good job of giving the sun an apparent 'surface,' but it is by no means solid, and the sun extends well above the photosphere.
So if you were invincible, impervious to the incredible heat of the sun, what would happen if you tried to stand here? Well, you'd fall like a rock. The density of plasma in the photosphere is far less than the density of earth's atmosphere- you'd fall as if there's almost no drag. It would be like freefall- very, very hot freefall.
So would you ever stop falling? Yes! Why? Bouyancy, from your relative density. Denser things sink, like rocks in water, but less dense things float, like helium balloons in air. And remember, the sun gets denser as you go down. The core is a hundred times denser than you, so if I tried to put you there, you'd float up. Wherever you start, you'd eventually stop when you reach the part of the sun that is just as dense as you, about 1 g/cm3. Coincidentally, that's halfway down through the sun.
Needless to say, I don't know how you're planning to get yourself out of this mess, but I hope you brought some spare oxygen tanks.
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Light Years Ahead | The 1969 Apollo Guidance Computer
The YouTube algorithm knows me well. It gave me an hour long lecture that discusses the amazing engineering of the computer that drove the Apollo mission to the moon. Dense and well communicated, I quite enjoyed it.
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I ask any American, what happened in 1492. They will tell me, 'well Columbus sailed in 1492' and that is correct, he did, but that is not the only thing that happened in 1492. In 1492, England and France signed a peace treaty. In 1492 the Borgias took over the Papacy. In 1492 Lorenzo de Medici, the richest man in the world, died. Okay. A lot of things happened. If there had been newspapers in 1492, which there weren't, but if it had, those would have been the headlines. Not this Italian weaver's son taking a bunch of ships and sailing off to nowhere.
Okay, but, Columbus is what we remember. Not the Borgias taking over the papacy. Okay? Well, 500 years from now, people are not going to remember which faction came out on top in Iraq. Or Syria. Or whatever. And who was in and who was out. And, you know... but, they will remember what we do to make their civilization possible.Okay? So this is the most important thing we could do.
The entire clip from Dr. Zubrin's talk is worthwhile, but I especially love the above segment. I haven't fact checked him or anything he said, I don't know if those things did happen in 1492. I have no reason to not believe him, but it's the Internet so giving a bit of warning. But his answer on why going to Mars is so important is just excellent.
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NASA Perseverance rover has Twitter account. Here's what it's saying.
A look at the team behind Perseverance's social posts.
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Incredible
I watched the entire stream leading up to the landing, and grew increasingly nervous as everything went perfectly. I was afraid of some mysterious event and the loss of signal. With no clear way to know what happened. But instead it went smoothly and to plan. Simply incredible.
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I have turned on the Mars mission's stream on YouTube and will be watching to follow Perseverance's attempted landing. I am incredibly nervous, this would be an amazing engineering and science feat if it works.
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'Any evidence for Planet Nine is gone': Scientists dispute probability of mystery planet
I remember the idea of Planet X as a kid. I assumed it wasn't real since we never got real evidence of it, but part of me always wondered if maybe it was out there. It seems the answer is no. Maybe it was a large comet that briefly got snagged by gravity but is gone now? No idea. An interesting read.
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