Green Baron

The giant iceberg A68 that broke off from the Larsen iceshelf in Antarctica last year, is preliminary finally drifting free. It cleared a part of seafloor that has been cut of from sunlight since ~120.000 years, the last interglacial. The part is assumed to have life conditions like in the deep ocean. It will be interesting to find out if, when and how life gets back, now that nutrients and sunlight have free access.

The door bell, of course

I feel urge to make a statement: I named the term "cannibalism" in reaction to @MinimumSky5's assumption that "The fact that we can differentiate between cooked antelope and cooked people is likely a unique trait to humans." to show that this is not the case. It is simple, preying on the own species is called "cannibalism", and the pros and cons are quite reasonably discussed in science, that's all. Sure, cannibalism has different connotations from people in large bronze cauldrons on engraved pictures of the 18th century ("Would you mind stirring with your feet ? You're about to overcook ...") to rationally supported assessments of its effects on evolutionary fitness and energy balance and shades in between. Hope that wasn't too impertinent now :-)

"Sabotage" was last shouted by Musk & Co. when their rocket popped on the pad. They even believed to know whom to blame and made that public without a deeper insight. I've never heard such a thing from Roscosmos or any other space manufacturer at all. Also, Roscosmos are up to now the only ones who reliably bring persons to space & back. Let us all hope that future vehicles will perform as reliable as the Soyuz family. While it is strange to have an apparently manually applied hole were none belongs, speculations lead to nothing except arguing. Se we better wait until the cause for the mistake is found, thinks me :-)

Hu ? It is a mid level cloud field ... not even sure if it led to rain at all.

I fear not. Only the trivial case for a single moon (like ours), being tidally locked to its planet, it is one orbit (~27 days) + the time earth moves around the sun during that period. In total that is one synodic period, time between oppositions of planet and moon towards the sun, if i am not erring. The lunar day so is considerably longer than its orbital period around its planet (wikipdeia says 29.5 days for our moon, but forgets to take it into account for Titan i see). For a non tidally locked moon, or if there are more than one moons in resonances or not it clearly goes over my head, i must pass.

Don't even ignore at all. :-)

Clear case for Kerbal Alarm Clock !

Yes, and the "food" has already split up some nutrients to integrate the food's food and spent energy in that process. The predator of the first food saves part of that energy that the food had to bring up to digest the food's food :-) And it is more complex as other costs (e.g. for procurement) might be involved. But this has all been taken care of and it boils down to the initial statement "energetic advantage/evolutionary disadvantage". May be useful in times of need, but generally not the first choice.

Nope. There is no such difference.

Yes, it is a slight energetic advantage, but can be an evolutionary disadvantage. https://www.sciencedirect.com/science/article/pii/S0022519303003370 and https://www.sciencedirect.com/science/article/pii/S0092824076800171 Back to the point: Humans are the only species who controls fire, but not the only species who differentiates in a prey relation between the own and other species.

Yeah, use of fire is very old, connected with Homo erectus ~2my ago. And i would not be surprised if somebody found traces of fire in conjunction with Homo habilis. Use on the one side and control of fire are regarded different things though, the latter being much younger, maybe less than a million of years, that's the official version. But some say that for humans to survive e.g. in European ar Asian climate the control of fire is a prerequisite. This is an open question, though. Every organism with a proper receptor and processing unit steps, flies or crawls away from a fire. But cannibalism is not rare in nature. In principle, the proteins and nutrients from the same species can be integrated with less energy than that from other species. So some organisms prey on their own species in time of acute need. Nevertheless, in the medium to long run, that's not an evolutionary "success story" for a population if it doesn't multiply very rapidly in times of plenty. In modern humans, the rare cases of cannibalism are mainly connected with cultural things, like rituals (disposal, conflicts, ...) or simply morbid individuals(*). But you are right, for the average human individual the perception of devouring another human is repellent, if cultural dictate doesn't call for it. Which is very rarely the case despite of horror stories from early explorators ! But, i must say, that there is no evidence that the differentiation is unique to humans. (*) and very few known isolated cases to avoid starving.

Education and in my own university were i'd just hang around as an eternal student and haunt the lectures and tease the lecturers. Incognito of course :-) Remains to say that having plans for an unlikely situation is something very different from actually being that situation.

Before or after taxes ?

Welding a thin aluminium sheet is not trivial. And such a spot could probably be seen from afar by the big bulge. The order of the hour was probably "make it invisible" not "seal it professionally" :-/ I am mean.

Terminal velocity is the velocity at which air resistance and gravity cancel each other out. Iow, the maximum velocity a free falling body reaches in the atmosphere. The formula involves calculating weight and drag, thus includes density and drag coefficient (~shape of the body) as variables and sounds like this: https://www.grc.nasa.gov/WWW/K-12/airplane/termv.html

sed :-) No, seriously. Neither is really intuitive and they can't deny their heritage as being not really screen oriented. I came late to Linux and the animosities between vi(m) and emacs don't bother me. But somehow emacs is too huge and slow imo if one doesn't use it regularly. I know one can do a lot with it up to an IDE. So, if i am in a terminal and > or | aren't enough it is nano for me as well, in which i regularly provoked the "grumblegrumble" message that was taken out just lately :-)

Hmmm .... they could be used as leak indicators. They'll float slowly towards the leak and seal it with their body. :-) Browsing up through the thread, kudos to @lajoswinkler who pointed this out before an official excuse came out.

No, i probably do not have an idea. But having studied prehistory and paleoanthropology, i honestly do feel a little bit with you. You are not alone here :-)

A ~300Wp panel weighs a fraction (1/3 to 1/2) of that actually, has >double the power output under optimal conditions, with framing and wiring. And costs little. And it has no moving parts and lasts many years without maintenance ;-) Edit: i mean the consumer grade mass product ... Editedit: You are not completely on the wrong track, @Cassel, wherever there is a temperature gradient a stirling engine would principally make sense. This would be the case in small geothermal (the hydro variant above) applications, it would be my first choice there because it is cheap then, small, easy to repair and maintain. But not in spacey applications, i guess. Solar power is the best choice there.

I have read this. A terrible loss. My apologies ! Cultural heritage, prehistory and history are at least as important as going into space.

Yeah, and if the thing it is mounted to is rotating in the sun, cooling and heating the sides alternating ? Because that was the original scenario which triggered the heating heating discussion, or am i wrong ?

Yeah, that's a different thing :-) We'll ask Elon if he would if he could. Be it as it may, i hope we have transported the notion that heat is carried away by radiation in vacuum, and that pretty effectively. This fact is actually (Science & Spaceflight !) an underlying working base of Astronomy :-)

I said a sheet of submillimeter. And the engine is a chunk of metal, that one huge difference.

The stirling engine is a pump. It would still need a motor and energy to get working ;-) Solar panels otoh panels are terribly effective for the use case. Actually, radiation can be much more effective than convection if the radiation area is large and differences huge. And the cooling curve is parabolic. That is what would make the thin metal sheet of the "car in space" radiate the first 100°C very quickla. Well, if you let it rotate and expose the one and other side to the sun in a perfect cycle of expansion and compression. But you won't get much power out of it ... A car's skin isn't a cm, it is less than a millimeter ;-)