It makes me so mad we don’t just tell the flight industry that by date X no planes that use traditional fuel can be produced, and by date Y that they won’t be allowed to fly. Doesn’t even need to a global agreement, if the European market is closed, than that could be motivation enough. And it would focus innovation on efficiency instead of frivolous stiff like this.
Astronomy: “a natural science that studies celestial objects and the phenomena that occur in the cosmos”
I suppose anything that happens in the universe is technically “a phenomenon that occurs in the cosmos” but this seems more suited to !nasa, which could definitely use the content. Would you consider posting it there as well?
I’m not the biggest fan of Lemmyworld, I prefer thematic instances such as Mander.xyz. Maybe we can consider this community as broader than strict astronomy?
I also prefer thematic instances, but try to find appropriate communities within those instances. Just because it’s coming from NASA, doesn’t make it astronomy.
Depending on which aspects of the project you think are important and want to discuss there are a few communities here that might be relevant.
Earth Science includes environment, and environmental impact seems to be the most popular talking point so far.
Noise and other forms of pollution are public health issues and there is a local community for that, although I’m not sure it’s really a great fit there.
Physics might be another choice due to the fact that a lot of physics is going into the engineering of something that reduces sonic booms.
Or maybe you just need to find the right thematic instance. For example, I’m registered on slrpnk for my climate, energy efficiency, and anarchism fixes.
Wow, that’s not something I even considered could happen. It does raise an interesting question though – how many more of these could be out there? Seems like it would require a whole-sky survey just to detect them.
Are those… Philips screws? Looks like maybe two dots indicating JIS (shallower angle, less cam-out, and #1 cause of stripped screws on Japanese motorcycles) but I’d really like to know why a hex or torx screw wasn’t used
I was curious about that too. They look like Torq-set to me, being that the slots are offset from the center of the screw. If that’s the case they’re shouldn’t be any cam out at all.
In either case the fasteners that were stuck appear to be Hex head, and the phillips looking fasteners just held a protective cover in place (?)
I would imagine NASA would know better than to use Philips for anything lol.
By the way there is a link on the page to more images of the assembly
From my amateur understanding of space, it seems to be a galaxy made of just primordial hydrogen and helium, back before the first stars formed and started creating heavier elements due to the fusion reactions that power stars and the eventual supernovas that further dispersed and helped to create even more heavy elements.
Another cool theory is that the first stars are thought to have been much, much more massive, possibly up to around a thousand solar masses since they were made solely of hydrogen and helium. It’s estimated that current stars couldn’t get above a few hundred solar masses at most due to the existence of heavier elements in modern gas clouds. I don’t understand enough to explain why the existence of heavier elements limits star size so I’ll leave that to someone smarter than me.
Someone correct me if I got anything wrong, again I only have an amateur level of understanding about space.
I think the heavier elements exponentially speed up stellar death. In part, the fusion of elements makes the core denser and denser each step of the way. Going from hydrogen to helium is twice as dense, but helium is still a good fuel so it isn’t an issue. As fusion continues through carbon and oxygen, it shrinks but still burns. Iron is the tipping point though because it doesn’t work as a fuel at all - it triggers a core collapse, the surface falls into the void, and everything heavier than iron is instantaneously fused and thrown into the universe.
So I would guess the lesser abundance of heavier elements early on delayed that process compared to today’s standards. Sort of like making a snowman in fresh powder and having to melt/wet the snow to make it pack vs having a little rain and higher temps after the powder to wet it
The amount of heavy elements present in a star when it formed will be neglible to the amount that will be created over time through fusion.
You can actually detect this through spectroscopy because the initial amount of metals will be present in the outer layer of the star. Heavy elements made through fusion will be mostly in the core.
The reason stars formed from primordial gas, i.e. only consisting of hydrogen and helium, is that such a gas will fragment less as it cools and collapses. Less fragmentation means heavier stars.
I only have a high level knowledge of the process though.
astronomy
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