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.
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.
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
That’s frustrating. Anyways, SpaceX! Turnaround record of 3 hours! Something fails, learn from it and launch another one. The ULA invests so much money and time, it makes every mechanical or propulsion failure seem catastrophic.
Obviously NASA engineers don't ever go to Youtube, I'm sure looking up "asteroid sampler stuck" there would have been a number of hack DIYers who showed a variety of techniques they've used.
Intriguingly, the two structures are at the same distance from Earth, near the constellations of Boötes the Herdsman, raising the possibility that they are part of a connected cosmological system.
Not only that, but they look suspiciously concentric when plotted out on the sky. I know that's jumping pretty far out there into speculation land, but it'd really blow our theories a new one if there are patterns in the cosmos this large. Neat stuff.
astronomy
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