It's their third space station actually.

The first station had three Shenzhou dockings, one uncrewed, two crewed (the first for 3 days, the second for 12). The second station also had dockings with the automated Tianzhou cargo module and was occupied for 26 days. Both of those stations were very small, with not much more pressurized volume than the Shenzhou capsules themselves.

Camera lenses are literally telescopes. The OP is using a 105mm lens which is equivalent to a small refracting telescope (4"). The diffraction limit on an aperture that size is around 1.5 arcseconds, which is enough to resolve most naked eye planets into multiple pixels. Jupiter is up to 50 arcseconds across, Mars is up to 25.

Many refracting telescopes have smaller apertures, and "good" amateur telescopes start out at not much larger (at 6" or 8" apertures). Of note, Galileo Galilei's telescopes had apertures of 15mm, 26mm, and 38mm, which he used starting in 1609, 1612, and 1620, respectively. Newton's pioneering reflecting telescope, built in 1668, had an aperture of 2 inches (50mm).

The main constraint is always going to be atmospheric seeing. Which is where digital photographic techniques and stacking comes into play. With a modern top tier astronomical observatory they would use adaptive optics to cancel out the effects of atmospheric distortion. If you don't have that option you can simply use lots and lots of individual exposures. Each exposure represents a snapshot of the atmospheric conditions at a particular moment. If you're lucky you can get a single frame or a part of a single frame where by chance the air happens to be just right to have a minimal amount of distortion and blurring. With enough frames you can use a computer to select the individual frames and portions of frames with the best seeing and digitally combine them together to improve the overall signal to noise ratio of the final image. This allows you to approximate the performance of the same optics without atmospheric distortion.

In Earthly experience quarks are confined within small particles such as protons, neutrons, and other more exotic but short lived particles. Under more extreme conditions quarks can instead exist in a more unconfined form in larger "chunks" than just protons or neutrons. One example being a quark-gluon plasma which requires very high temperatures but is potentially denser than nuclear matter because it can be more highly compressed. Theoretically there might be other states of "quark matter" which might be stable in conditions other than those required to sustain a quark-gluon plasma. This could include "strange matter" and other exotic collections of large numbers of quarks. We've studied quark-gluon plasmas experimentally but we have never created other forms of quark matter so they still remain the subject of speculation and research.

It may be possible that there are routes to creating a higher density object than a neutron star that don't involve a quark-gluon plasma but we don't know for sure. In any event, when a neutron star is crushed down enough (whether via creation of a quark-gluon plasma or through some other form of matter) an event horizon can form. Very early on you'll have a bunch of very high density matter which is still being pushed inward with incredibly force/speed due to collapse and this will feed directly into the event horizon causing it to grow. At some point the rotation of the star/black hole creates a little bit of a delay in how fast matter can fall into the event horizon as an accretion disk forms and that matter takes several seconds to fall in. The black hole feeding on ultra-dense matter in its near proximity releases a lot of energy through the glowing of the accretion disk and the formation of axial jets (due to tightly wound magnetic fields from the accretion disk), creating some of the most energetic events in the universe: gamma ray bursts.

In any event, like everything else in the universe black holes typically have some amount of rotation, which causes the event horizon to have an ellipsoid shape. When an event horizon is created it's sort of like a space-time relic of the gravitational fields of its progenitor. As matter falls into the black hole it basically encapsulates the old event horizon in a new larger event horizon.

We need to change the whole system of how research is conducted, especially the economics of it. This sort of thing (along with the whole reproducibility crisis) is caused by "publish or perish" norms. As long as there is intense pressure to not just get work done but get "the right" results then there are going to be individuals who give into the pressure and fudge things. The problem is that a great many folks are fudging things, cutting corners, jazzing up results, "p-hacking", etc. The vast majority of this is arguably not that serious, but when it's so prevalent it leads to a whole culture of focusing on the wrong things and a deterioration of rigor and intellectual honesty, which again will lead to the inevitable case of something squeezing out through the cracks in a way that is egregious enough to be a serious breach of ethics.

Orion is a crewed spacecraft designed for human missions to the Moon, it's not a space science vehicle designed with instruments for observation, all of its cameras are basically engineering cameras.

A "black hole" is three different things. There's the physical object that creates the black hole, and as far as we can tell in our universe this is usually an object that collapses beyond the density of a neutron star. Likely the extreme pressure from enough mass compresses the neutron star into something like a ball of quark-gluon plasma, but we don't have a ton of knowledge of materials in these conditions so it could be something else as well. When that collapses small enough to form an event horizon everything changes, you have the before times and the after times. After the event horizon forms the outside universe is cut off from the interior of the black hole. It's not only impractical for matter or light to escape the event horizon, it's impossible because there's no space-time trajectories that exist that make that connection, everything is one way, you can enter the event horizon but you can't leave it. At that point whatever the object had been before becomes merely historical trivia for the outside universe, the only thing that's relevant is the event horizon, a phenomenon of space-time. Within the black hole we don't entirely know exactly what happens, and we can't exactly check either so this is still the subject of a lot of ongoing theoretical physics work. Very likely we won't have a good understanding of what happens inside a black hole until we develop a theory of quantum gravity or something equivalent, and it doesn't look like that's going to happen anytime soon.

There is this idea of the information paradox of a black hole due to the fact that they "evaporate" through Hawking radiation. This happens on far too long a timescale to be relevant to human experience, but it's an interesting theoretical problem. In theory Hawking radiation should be uniform, which means that all the quantum information locked away inside the black hole (things like how many protons and electrons fell into it, which in theory are conserved quantities) could essentially get deleted, in seeming violation of conservation laws. There are some interesting theories about how to resolve this paradox, but they are still being developed and it'll be hard to verify them.

When a star exhausts a given fusion fuel in the core it'll undergo gravitational contraction. If the star is very light this might just be the end of things, eventually it'll just be a dead ball of fusion ash. Depending on the mass of the star this process can trigger subsequent eras of fusion reactions with heavier elements. Stars around the mass of our Sun will eventually fuse helium in their cores, and slightly more massive stars will fuse carbon as well, before ending their lives as a burnt out "white dwarf" husk that has lost the remaining hydrogen in the outer layers. Yet more massive stars will continue to fuse elements all the way to iron. And such stars are always so massive that if they can fuse elements up to iron they will also collapse to become either neutron stars or black holes.

When such massive stars (generally over 8 solar masses) near the end of their lives they begin fusing silicon into nickel (which decays into iron). After this point fusion doesn't release energy so it cannot create further heat which would resist gravitational contraction of the nickel and iron plasma core. At some point over the course of literally just a few days of silicon fusion this super dense core becomes large enough that the pressure at the center becomes higher than even electron degenerate "white dwarf" matter can withstand, so it begins collapsing into a neutron star (or even more exotic materials).

The dynamics of this situation are very complicated and depend on things like the spin of the star, the mass (of course), and the metallicity of the outer envelope. Metallicity (the abundance of elements heavier than hydrogen and helium) in the envelope greatly affects energy transport so it can make a huge difference in the evolution of the collapse. The neutron star forms at an enormous temperature as gravitational potential energy is converted into heat from the core contracting from over ten thousand kilometers across to just about 20 kilometers across or so. Beginning from a temperature of over a trillion degrees the neutron star material rapidly cools down via the Urca process through neutrino emission. Over a timescale of about 10 seconds an amount of energy is released in the form of neutrinos equivalent to the Sun's entire output multiplied by 800 billion years (which to be clear is much more energy than the Sun will ever produce). About 1% of that energy ends up deposited in the outer envelope of the dying star, which can heat it up enough that it blows off of the star in a supernova explosion.

If the star is heavy enough then the collapse into a neutron star continues and a neutron star is created that is too massive to resist further collapse into a form of matter dense enough to form a black hole. This could be because the core is too heavy, or it could be because the process of coupling neutrino energy to the outer envelope of the star is ineffective at blowing it away (either due to low metallicity or other factors). The envelope can then fall back onto the neutron star and crush it into a black hole.

This is still the subject of ongoing research but that's the general outline of how you can get a neutron star vs. a black hole.

Nothing escapes the event horizon. The area surrounding the event horizon still hosts extremely strong gravitational fields in a comparatively small volume, so it's a source of extreme events. Including superheated accretion disks which glow very brightly, strong magnetic fields, and axial jets of high energy plasma and particles. But all of these phenomena occur outside of the event horizon. People say that the jets come "from the black hole" though it's more accurate to say that they come from near the black hole, it's just the nature of language.

Pursuing the goal of making Earth multi-planetary, of creating pockets of human civilization which exist outside of Earth is not and never should be a replacement for taking care of Earth and making human habitation of Earth more sustainable. Indeed, such efforts should be and likely will be not just parallel to but complementary with improvements in how we live on and take care of Earth.

Yep. But whether it happens with burning coal that was buried forever or using sunlight that wouldn't have landed on Earth the result is the same. Replacing fossil fuel power generation with space based solar is net neutral with regard to direct heat production but avoids the generation of greenhouse gases which result in orders of magnitude more heating of the Earth (due to trapping heat that would otherwise have escaped), so it would be a huge win in that case.

Compared to where we are now, worrying about the impact of direct heating from human activities would count as a "nice problem to have".

Ultimately it doesn't matter how the transfer is made, it's the question of usage. Importing energy to Earth then using it would technically generate heat. But it's such a tiny amount compared to global warming heating that it's not worth worrying about at the current scale.

Oh yeah, it totally would, let's check the scale of the problem to see if it's a concern.

Annual global energy usage is about 500 million terajoules per year. If all of that energy is gathered off Earth and beamed to the planet that would ultimately end up being released in the form of heat, which would potentially heat up the Earth.

In contrast, the amount of excess heating due to human caused greenhouse gas emissions translates to about 24,000 million terajoules per year, which is fifty times more heating. So replacing any carbon emitting heat source with space based solar power would still be objectively vastly advantageous in terms of reducing global warming.

One thing people forget about is that water permeates through "solid" soil as well as just sitting on the surface in the form of lakes, rivers, and oceans. These sub-surface aquifers and water tables still exist today on Mars in the form of permafrost and sub-surface glaciers. The water that exists on the surface is mostly in the form of a small amount of water vapor in the atmosphere and ice in the polar caps. The rest of the water that used to exist on Mars has mostly been lost to space along with a, likely, heavier atmosphere at some point. The lighter planetary mass and lack of a magnetic field means that it's comparatively easy for molecules in the atmosphere to directly evaporate to escape velocity or to get dragged away by the solar wind. The same thing happened with much of the water on Venus, even though the gravity is much stronger there (but the planet is also much hotter).

The greenhouse effect as caused by atmospheric CO2 and methane traps heat like a blanket within the lower atmosphere. This has the adverse effect of causing cooling of the upper atmosphere, including the thermosphere which reaches into low Earth orbit. A cooler thermosphere reduces drag on satellites.

Solar activity results in a higher level of especially UV light which puffs out the outer atmosphere during solar max, but this is an external input not a change in how heat is distributed within the atmosphere which is what is going on with the greenhouse effect and climate change.

These details are all in the article, which I'm sure you read but forgot.

If it weren't hard to do someone they'd be doing it. Three space programs have recently built Mars rovers/landers (NASA, CNSA, and ESA), and none of them have had automated dust removal systems. If it were easy you'd think at least one would do it. Logically the conclusion should be that it's not as easy as it seems.

It's not brainstorming though, it's just dismissiveness of a kind. It's trying to put forward this narrative that it's an easy problem, and it's not. If folks are serious about coming up with a solution to the problem, that's great, but it's unlikely to result from someone with no expertise in the field spending 30 seconds thinking about it and then moving on.

Which is what a lot of the pushback against those solutions illustrates, is the lack of depth of thinking about the problem that folks who "found a solution" exhibit. There are helpful suggestions and then there are half-assed unhelpful suggestions, and almost universally the "ideas" put forward by randos are the latter. Which is unfortunate, because there is value to collaboration and wide open problem solving, but this is not that.

Even more than that it's easy to see the root of these comments as fundamentally unhelpful. The starting assumption is that people are being stupid (across three separate national/international space programs) are missing something obvious, which comes about from this bias toward personal superiority and intelligence. Someone who was actually heavily invested in trying to help find a solution to the problem would start off by asking questions not proposing solutions. They would ask what the constraints are, what the full details of the problem are, what solutions have been investigated and found unsuitable, and so on. Instead you get people who just ride high on all of their assumptions and ignorance and don't even have the self-awareness to realize that's a problem. Is it smart to assume that Martian dust and Earth dust is identical with identical properties? Probably not, but it's a very common assumption by the solution havers. It's really easy to pretend that lazy, unhelpful advice is being made in good faith but it's generally not, and it's not being made with any level of thoughtfulness or effort behind it.

A good little comparison point here comes from the movie Pulp Fiction. In one scene a character, "The Wolf", is brought in to solve a problem, and the first thing they do is ask a bunch of questions to identify the scope and details of the situation, and then they proceed from there. That's just standard practice for any situation, even if you are a subject matter expert. You need to learn first then you can try proposing solutions. And if you aren't a subject matter expert (in, say, the design and operation of interplanetary spacecraft) then you should probably spend some time learning some details there as well. With that in mind, ask yourself what it would look like if someone really, truly was trying to be helpful in solving this problem, and if they put more than a few seconds of half-assed work into it, and then ask yourself how often you see comments of that nature that are actually thoughtful, informed, and potentially helpful.

Sure, but then how are you going to make it work? You have to hit the whole panel, which probably means some kind of armature. That's not exactly trivial in terms of complexity, weight, etc. when you're talking about adding something to a spacecraft. And then anything like that you need to do testing on, already you're spending millions on something that may not work very well.

How do you pull it away? What mechanism is used? How do you test that the sheet doesn't reduce the amount of light received? How do you test that the sheet doesn't increase the rate of buildup of dust? Once you get into the nitty gritty you find out it's a huge engineering problem with lots of costs and time associated with getting it even remotely right, which is why of the three organizations which have recently built Mars landers/rovers they've all decided it's not worth the investment of trying to mitigate dust build up, at least not yet.

If it were easy they'd be doing it already (NASA, CNSA, ESA). So far the cost/benefit of putting in the legwork to do all the R&D to figure it out hasn't seemed worth it. That'll change at some point in the near-future, no doubt, the questions are when and why. It also may be that there are not really great low mass solutions and the only things that work well are bulky and cumbersome, but ultimately we don't really know. We know that the most obvious solutions (like wipers or brushes) are probably not as workable as they seem at first blush.

The ISS is huge. Also, you can't see any detail on the ISS with the naked eye, it just looks like a dot.

Go look at images of the ISS from the ground, the tech for that has gotten a lot better in recent years but there's still not much detail. Consider that the X-37B or China's spaceplane is about the size as a single module on the ISS and you start to understand why there aren't any public pictures of it.

Using large telescopes with special tracking capabilities or on orbit assets capable of taking photos of other satellites would make it possible to get decent imagery, but all that stuff is classified.

It's 9 meters long and three hundred kilometers away, moving at orbital velocity. You get a good picture of it if it's so easy.

What's fascinating is how close we came to having a serious military presence in human spaceflight. The US were planning on launching the "Manned Orbital Laboratory" (MOL) in the '60s but it ended up being sidelined by improvements in spysats as well as budget overruns before it was finally cancelled. The US continued dabbling with military uses of crewed spacecraft through Skylab and the Shuttle program but for the most part it was pretty boring stuff. Meanwhile, the Soviets launched the Almaz series of stations in response to the MOL program. However, out of 3 stations only one was able to operate successfully. Also, as in the US improvements in automated surveillance satellites undercut much of the program's justification for existence.

But then you get to the '80s. The US has the Shuttle which performs both civilian and military missions, of unknown scope. The Soviets decide they need a Shuttle too so they build their own (Buran). The Soviets also respond to the bluster of Reagan's announcement of the "Strategic Defense Initiative" to initiate a program to build weapons platforms in space, starting with an enormous 80 tonne military station replete with a laser canon. This vehicle, Polyus or "Skif-DM", ends up re-entering during launch due to a malfunction in 1987, completely changing the whole arc of spaceflight history. Meanwhile, the Buran, launched by the same heavy lift rocket Energia, launches a year later in an uncrewed flight. The Soviets slowly realize that there isn't some magic to the Shuttle and it's actually not that great of a vehicle (notwithstanding the cool factor) so they don't pursue the use of it much, then the following year the Berlin Wall falls, 2 years after that the Soviet Union collapses, and 2 years after that the Shuttle-Mir program begins, with Russian cosmonauts flying on the Shuttle, Shuttles visiting the Russian space station, and so on, as a prelude to the ISS.

Every exposure is 18 bits per pixel, each channel is a separate exposure. So a full image of one patch of the sky would be either 5 or 6 individual exposures for each color channel (plus a clear exposure) which would be equivalent to 90 or 108 bits per pixel.

There isn't a 1:1 match of filter channels to RGB colors but for just the 3 color channels closest to RGB that would be the equivalent of 54 bits per pixel, or 18 quadrillion colors.

It's 1 channel per image not RGB, this camera doesn't have a mosaic filter on the sensor itself the way consumer digital cameras do. Like almost all scientific imagers it instead is monochromatic but uses filters that can be rotated into place through an automated mechanism. This provides higher resolution for each color channel while also allowing for adjustments to the exposure timing for each channel depending on how much light it passes (which is much more desirable from a scientific standpoint). This particular camera will have 5 wideband color filters covering the visible through near-infrared bands but it won't have an exact match of red, green, and blue color channels.

So an exposure of a particular patch of the sky in all color channels will actually look like 5 successive exposures (or 6 if there is an unfiltered pass) through each of the filters.

It will have 18 bits per pixel of dynamic range.

Let's break this down, as far as we know the only way to get a neutron star is when the core of a very massive star collapses when it dies. The inner core is crushed to super high density electron degeneracy conditions (white dwarf star matter) and then a core of that matter builds up that is too heavy to resist further collapse, and then a neutron star forms. This would naturally lead to a minimum mass for neutron stars, at about 1.44 solar masses, which seems to be born out by observations, so far. This object appears to be a neutron star density but only 0.7 solar masses, which would put it more in the realm of what should just be a white dwarf.

One other issue is that neutron star material is not necessarily stable under less pressure, and would simply decay into atomic matter.

This raises the question of how this object got from point A (the core of some dying star, most likely) to B (a sub-stellar mass neutron star), and there are lots of possibilities. The possibility being floated here is that the object is not a neutron star per se but rather a "quark star" or a "strange star" where instead of being made up of mostly neutrons it's actually made up of an arrangement of quarks with a mixture of strange quarks in a configuration that allows it to be stable in that mass range. It's been proposed that it may be possible for "strange quark matter" to exist in forms which would basically catalyze the conversion of neutron star material into it at similar densities to neutron stars. It may be that this is an example of a fragment of a neutron star that underwent a conversion to a quark star and then lost some of its mass in some way, or it might be a more direct conversion of a white dwarf into a quark star. There are a zillion questions still to be answered and this is an intriguing piece of evidence, assuming it holds up to scrutiny.