Entropian

The primary consequence of warm sensors is a higher read noise across the entire sensor (which, keep in mind, is tiny) and less so local artifacting on parts of the sensor. If there's any frames available with a completely dark environment at the same exposure, you can do a field subtraction to eliminate some of the noise. I think that this is largely a nonissue at least compared to the wildly out-of-focus image, which is causing far more data loss than read noise.

The sheer number of channels posting this garbage in the quantities I see is highly concerning to me - a lot of young people these days consume media through places like YouTube and I can't help but worry that these kinds of things are poisoning the waters for future astrophysicists 10-20 years down the line.

I believe butyl is used in KF joints as an O-ring polymer, so it'll be a damn sight better than vinyl. Aside from something like Viton, butyl should be in the upper tier of polymers you'd want to use. An air maintenance program is a necessity, but that doesn't mean you can just wave away any air loss mechanism with it. Vinyl in particular is a serious offender when it comes to outgassing, and you'd want to avoid it at nearly all costs. Sure, it's pretty easy to apply, but I'm sure the smart dudes at NASA or some other group would be able to come up with a method for a lower-outgassing polymer. The paint-based idea is much closer to what I had in mind. One can just spray a substrate on the walls, then cover it with a stronger sealant, like some kind of epoxy perhaps. In my experience, epoxy cured under vacuum has pretty low outgassing at least.

Very late to the party here, but vinyl won't work. Most polymers have a very high porousness to air, and thus undergo an effect called "outgassing." Air inside the chamber will slowly move through the vinyl into the rock fractures over time, but the more surface area you have, the faster it'll be. Incidentally, this is one of the primary reasons that the highest-vacuum joints entirely avoid polymers; instead, they cut annealed copper to form a joint that doesn't outgas, unlike polymer O-ring seals. If you're interested, you can look into "Conflat" and "KF" vacuum joints.

Keep in mind that if you pull energy out of a star's core, it will just shrink until hydrostatic equilibrium is reachieved. If you somehow reduce it to a gas cloud, I'm pretty sure that the mass and density would put it above the Jeans mass, which means that it would just re-collapse into a star. The time it would take to collapse is definitely a lot longer than a human timescale, but is still very short in the grand scheme of things (Kelvin-Helmholtz timescale).

AGB evolution is outside my field of study, but I'm pretty sure that with the little data we have about the helium reignition, the luminosity surge would be far from what's necessary to deconstruct the planet. I do believe that there's evidence for pulsational mass loss in AGBs, perhaps from the reignition, so maybe the ejected mass would ablate away the planet over a long enough time? Ultimately, granular data on AGB evolution is scarce and the mass loss mechanisms in them is also largely unknown, at least empirically.

You'd need to define "little pieces" more rigorously in order for this question to make sense. Keep in mind that if you don't gravitationally unbind the planet, the little pieces will simply coagulate back into a single, slowly-cooling object, leaving you back where you began. "Thermal pulse" is a little vague. If we're talking about the core collapse of a massive star, the ejecta can and likely will annihilate any nearby planets. Let's assume that the progenitor star collapses and the resultant SN reaches a peak luminosity of order 109 solar luminosities (slightly below 2023ixf's IIRC). At a Uranian radius from the collapse, the flux would be about 7.5*1019 watts per meter squared. Assuming the planet is nonreflective (completely absorbs the light) and we approximate the cross-section as a circle with the same radius as Uranus, the absorbed power is about 1.5*1035 watts. Compared with the gravitational binding energy I estimated earlier (~1034 joules), the luminosity of the SN alone would be enough to dump a full gravitational unbinding energy into the planet every 15th of a second or so. So yeah, at least from a very rough estimate, a planet like Uranus would definitely be destroyed.

Keep in mind that that's just the energy to vaporize it. If you want to destroy the planet you need to overcome its gravitational binding energy, which is of order 1034 J assuming constant density. The energy to vaporize is 3 orders of magnitude smaller, which is essentially negligible. Also FWIW, supernovae deal with significantly larger energies of order 1050 to 1051 ergs. 1034 joules is nothing compared to core collapse SNe at least.

I highly suggest you take a course in, or read a book about planetary astrophysics in this context (e.g. Lane-Emden equation/polytropes, basic equations of state) and really get an idea of how unrealistic the planets are. This seems like a minimization of a pretty serious aphysicality IMO. You're trying to physically justify a low-order approximation to reality; an outcome like "black holes that miraculously balance themselves" is totally expected when one takes such a path.

The whole astrophysics community is dying for a few of those - with JWST up and running now, aperture fever is at an all-time high

They very much released information within the last 20 years - it's just that they found that the thing doesn't work at all and the idea is fundamentally flawed.

Rockets are flying. These hypersonic aircraft are not. I think it is incredibly naive to presume that a novel system will go from not even having a single flight test to "obsolete" a flight-proven design... all by the end of next year. It could happen, but certainly not over such a minuscule timescale.

The rocket is called "Superheavy." I highly doubt he has a problem prefixing the word "super" to things

This chain has really made me uncertain about my expectation value for relevance, now I'm not sure what diraction this is going to go...

This is what amateur astrophotographers do - the process is called "stacking." There's many, many ways to eliminate unwanted pixels from individual images before stacking. In professional astronomy, stacking is less prevalent for a variety of reasons (mostly because temporal information is lost), but the data analysis and sorting is far more advanced generally.

Merely having one, or even multiple satellites in an image does not mean that it's "destroyed." It may look unsightly, but the area of the image covered by the satellites is generally small. Most often, the object you actually care about is missed entirely by the satellite(s), and even if it isn't, you can simply remove the (small amount of) pixel data saturated by the satellite and use data from another image. While this is certainly true, actually building and operating space telescopes is expensive, which doesn't match well with the small amount of funding the astronomical sciences generally get. I'd love it if ground-based astronomy was shunned in favor of space-based astronomy, but ultimately the capacity and funding for it isn't present yet for it to even begin to become feasible.

I'd like to point out that there are many professional astronomers who have no real concern about Starlink, mostly because it's not "destroying" ground-based astronomy. Even in fields where satellites are having an impact, there are systems both in place and in development for minimizing their effect.

Early observation, photometry, and spectroscopy of supernovae is very much a growing field and has only recently become more common. I'm sure a lot of people would really appreciate more detailed photometry of eruptions like that, but ultimately the systems for automatic detection and response have only come up in recent years. To somewhat back up my words, I actually work in research on data collection and analysis of young supernovae.

It's only around 800 parsecs away; if SNEWS ever actually triggers for once, then it'll be in a case like this.

I did some photometry on it in H-alpha, OIII, and SII a while back. I'm not sure if I still have the data, so I'll pick up some more when it's clear here so that once it goes nova I can get a nice rise and plateau light curve. Hopefully the weather here will be good when it does actually outburst.

I have been testing and triple-checking all my equipment for tomorrow. All systems are go and I hope the eclipse gods smile upon me. GL to everyone!

I'm in Montreal now, looks pretty clear to me. Weather has me driving out east for 3ish hours past Sherbrooke, but it's looking good.

I was in Bend, Oregon for 2017 and now I'm off to Montreal for this one; I had my eyes on Dallas but after these forecasts, Montreal is looking a hell of a lot more promising. Hopefully it will go as well as 2017 did. I'm hauling along 7 years of accumulated equipment with me, so I really hope I won't have to wait until 2026.

Talk about beating a dead horse - at this point y'all are knocking on a skeleton Last I checked, SpaceX was doing perfectly fine without needing to check arbitrary boxes set by not-SpaceX on SpaceX's own missions.

Yeah. Well I was already interested in spaceflight since I had seen the launch of STS-125 in person, but my dad is somewhat of a disappointed physicist. He graduated top of his class at one of the best universities in the world for physics, but is in a different field now (life happens, etc.), so he was able to teach me a lot. It's not just about him though; I have a younger brother and after some help from me he was able to dock independently when he was 7. So far as I can tell it really just boils down to interest and effective teaching. I have really strong spatial reasoning so I assume that's the main reason. I'm not sure if maneuver nodes were even a thing then though, it was ages ago.