121–130 of 152 posts
One of the engineers said that the parachute's patterns was both for visually determining the orientation (with computer vision), but also hinted there was some secret message in it. (at 19:34 in the livestream)
10-bit encoding via the three rings of colored panels; spells out "DARE MIGHTY THINGS".
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Nothing about "interplanetary streaming" needs to be invented. The limiting factor is the size and power of the transmitter on Mars (or wherever). The MRO orbiter for instance is the highest bandwidth probe we've sent to Mars and it maxes out at about 4Mbps when Mars is closest to Earth. When Mars is farther it can only do about 500Kbps. That relatively prodigious rate requires the use of 34m receiving antennas on Ea…
Maybe that's what Elon has planned for the back side of the Starlink v2.0 satellites - to create an Earth-sized massively distributed phased array and get a super-high-bandwidth downlink from Mars.
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If only. >The minimum safe lower limit for the partial pressures of oxygen in a gas mixture is 0.16 bars (16 kPa) absolute. https://en.wikipedia.org/wiki/Partial_pressure If it was 20% that would be survivable with just an oxygen mask fwiw. Humans can go down to 16% atm pressure safely if they breathe 100% oxygen. The rest of the body can easily handle the pressure difference (1 full atm of pressure is equivalent to…
Uh....10 msw is roughly 2 atm. It’s an additional atmosphere. On top of...the one we live in at sea level. Also 100% O2 anything past about 4 msw will kill you. The MOD of pure o2 is 13 feet. Which is about 3.9 msw
There's a myth that at low atm of pressures you pop and such. This is not true. You may need to breathe in/out to adjust but pretty much every part of the body can handle 1atm of pressure difference just fine. The 10meters below was intended as a reverse example but the point holds.
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The more impressive part is that the sky crane shot pictures, video and data and had to download everything to the rover before it was cut loose. As soon as the rover wheels touched ground, the tether was cut and the lander flew away.
I'd like to know how they cut/released the tether, and if there's any fallback in case 1st release attempt fails. The entire mission is fucked if the tether release failed, or if the sky crane tries to fly away while still tethered.
Observations Open source bits and shout out: - The rover has an Intel-based PC running Linux. - The video is compressed using FFmpeg. - https://youtu.be/gYQwuYZbA6o?t=4027 Images and Video and Data! - 30GB of data. 23 000 images - https://youtu.be/gYQwuYZbA6o?t=562 Cam Fail on Descent: - 1 of 3 cameras failed when the mortar/parachute fired. - Some other items were damaged/disrupted during the firing as well – not de…
In future, please don't put prose in code blocks, particularly links. You have a lot of good info here, but it's hard to read and non-trivial to follow the links on mobile. Thanks.
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In future, please don't put prose in code blocks, particularly links. You have a lot of good info here, but it's hard to read and non-trivial to follow the links on mobile. Thanks.
Ugh Didn't realize HN converted lines like that. I was trying to make it a bit more readable. Thanks for the heads up! (Too late for an edit)
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I'd like to know how they cut/released the tether, and if there's any fallback in case 1st release attempt fails. The entire mission is fucked if the tether release failed, or if the sky crane tries to fly away while still tethered.
They use explosive bolts that attach the tether to the deck of the rover. They're almost 100% fool proof. Here's a Wikipedia entry, they're called pyrotechnic fasteners and NASA uses a lot of them. https://en.wikipedia.org/wiki/Pyrotechnic_fastener
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Uh....10 msw is roughly 2 atm. It’s an additional atmosphere. On top of...the one we live in at sea level. Also 100% O2 anything past about 4 msw will kill you. The MOD of pure o2 is 13 feet. Which is about 3.9 msw
As in if you go 10meters underwater your orifices experience 1atm of pressure difference. In the reverse to space but the point being you can handle this just fine. There's a myth that at low atm of pressures you pop and such. This is not true. You may need to breathe in/out to adjust but pretty much every part of the body can handle 1atm of pressure difference just fine. The 10meters below was intended as a reverse…
Its why in SCUBA you have to calculate MOD for nitrox. Because the partial pressures of oxygen will kill you. We only breath about 21% oxygen in air. And after rec depths, you often using different mixtures and take on decompression obligations, trimix, heliox etc. At certain pressures, things like HPNS will also have an effect.
You definately cant survive in a vacuum either with just a mask. Its why pressure suits are a thing.
As it got closer to the ground, it seemed really hard to get a sense of scale with that downward camera. It felt like the ground just kind of "appeared" right before the sky crane did its thing. How big are the rocks under it? It felt like they were either big (1+ meter) or just little pebbles. I really couldn't tell. Either way, this is seriously the coolest video I think I've ever seen. I cannot wait for more.
Hah, totally agree. I assume the thinner atmosphere causes the dust to behave as if our view is much closer to the ground than it actually is.