The Astronomy Thread
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AladainAF
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I remember watching some show that was really interesting, talking about the planet hunters, and the methods they use, and the wild thing was that based on at least what they are finding out there so far, our solar system is actually much more the odd-man-out than the norm. The fact that all the planets have decent/not unusual orbits, and things are not overly chaotic. Apparently the "norm" is for a total shitshow, basically.
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Cybsled
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The physics should be reasonably straight forward: the speed of the blades generates a difference in pressure above and below the blade. This translates into a downward force. That downward force offsets gravity allowing the helicopter to go up.
Without doing the full calculations, I can do a rough estimate for you quickly:
- Gravity on Mars is 38% of Earth's sea level gravity, so you need 62% less lift to hover. (This is totally engineering approximation rather than mathematical science, but whatever)
- Helicopters on earth can fly as high as 40,000' (when heavily modified) before the atmosphere is too thin to generate enough lift to offset their weight.
- The atmospheric pressure on the surface of Mars is roughly equivalent to the pressure at 90,000' - 187,000' on Earth
So yeah, a heavily modified (read: super light with high power to weight ratio) craft should be able to generate sufficient lift at some altitudes on Mars, but probably not for the altitudes of places like Mons Olympus (equivalent of 187,000'). One workaround would be to make a hybrid dirigible-drone. My thinking is that the reduced air resistance would mean that balloon would not generate as much drag, and the thinner atmosphere would make He volume required minimal, but I haven't done the calculations on mass of gas ratio to balloon skin to know what size is required to generate lift, so this may be a red-herring.
Thank you for generating a fun thought experiment for me this morning!
[1] How strong is the gravity on Mars? | Cool Cosmos
[2] https://www.quora.com/Whats-the-highest-altitude-an-average-helicopter-can-fly
[3] Earth Altitude with Equivalent Pressure to Mars
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Ukerric
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Which is why you get dirigibles as martian transports in this (old but always good) video:
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meStevo
I think your wife's a bigfoot gus.
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khorum
Murder Apologist
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FYI they got that guy to make the opening sequence for the first season of The Expanse.
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Dandain
Trakanon Raider
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Blurb says there is 200,000 stars in that image. Which is crazy.
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Brahma
Obi-Bro Kenobi-X
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Be sure to watch this in 2160p60.
That spew 5 secs in...How large you think that was?
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meStevo
I think your wife's a bigfoot gus.
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AladainAF
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This is a funny article. Ariane group whining about SpaceX being so cheap.
Ariane chief seems frustrated with SpaceX for driving down launch costs
It also gives a great insight to how the Europeans think, and why America kicks their ass at everything.
Ariane chief seems frustrated with SpaceX for driving down launch costs
It also gives a great insight to how the Europeans think, and why America kicks their ass at everything.
Article said:
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BrutulTM
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Cry more Frenchy.
On a slightly related note, a guy I grew up with is currently living in Russia as a consultant on a giant cattle ranch over there where they are trying to raise American style beef. He says a lot of people back home have given him shit for developing competition for American beef but he says don't worry, Russia will never be a threat to the US beef industry. He says everything is designed around employing as many people as possible and nobody cares about efficiency for anything. He had a picture of 7 people replacing a leaking hydraulic line on a squeeze chute. He also said that they have to fire people daily for being drunk at work or just not doing anything. Socialism rules.
On a slightly related note, a guy I grew up with is currently living in Russia as a consultant on a giant cattle ranch over there where they are trying to raise American style beef. He says a lot of people back home have given him shit for developing competition for American beef but he says don't worry, Russia will never be a threat to the US beef industry. He says everything is designed around employing as many people as possible and nobody cares about efficiency for anything. He had a picture of 7 people replacing a leaking hydraulic line on a squeeze chute. He also said that they have to fire people daily for being drunk at work or just not doing anything. Socialism rules.
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Oldbased
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Not to sound like a socialist liberal but it seems SpaceX which is clearly the leader now got into it to make a profit but more for the love of awesomeness. Some of these companies were hoping to make massive bankroll on a monopoly scale using NASA/Gov spending as a guide to how much they could rape companies for. This is one war I am glad Elon is winning because when it comes to SpaceX, near perfection and the impossible never seems just good enough.
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Ukerric
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I worked next door to Arianespace back in the 90s. And by next door, I mean, I just had to go thru a pair of doors and I would be in their main office. The VIP launch lounge was kickass (never got invited to see one).
I saw first hand how the space agencies worked. I knew that day the french would never launch a man in space. Ever.
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Big Phoenix
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Took out the telescope for a glance at Jupiter and what do I see? Io getting its weekly gang bang;
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Cybsled
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Tuco
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Ive heard multiple times thst the cowboy culture of thr United states produces exceptional beef thst is hard to beat.
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khorum
Murder Apologist
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Good sentiment but wrong.
Japanese beef is some kinda fucking ZEN bushido witchcraft beef dude.
But the best is Spanish. They do aged beef better than anyone else and they do some kinda totally batshit thing where they pamper the bulls for FOURTEEN YEARS before butchering them for a totally different flavor. Not even Kobe/Wagyu comes close:
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