461–470 of 475 posts
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Was a hole actually punched in the wing, or was it just the tiles that were knocked off (and then the heat melted the leading edge of the wing)?
It was a hole punched in the reinforced carbon-carbon panel that made up the leading edge of the wing. They didn’t use tiles on highly curved parts of the Shuttle, like the nose and the wing leading edges. Those areas were structural heat shields, so not tiles at all.
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> because we risk contaminating Mars with organic stuff coming from the Earth. What is the alternative, not go to Mars?
Do actual science. Send robots there, like Curiosity and Perseverance. And over all: start recognising that there is no point in sending humans to Mars other than "uh uh it's cool we sent someone there and they came back alive". I have nothing against the fact that it is cool. And I watched Artemis enthusiastically because it is really, really cool. What I hate is when people seem to be so sure that this is "the new…
Fair point but if you want to inspire other humans you need to send humans not robots.
Glad that they're safe and sound. It's worth pointing out that this is the first extremely public, widely acknowledged high risk mission NASA has done in over 50 years. The Shuttle was risky, but it wasn't thought of or acknowledged by NASA as being risky until very late in its lifecycle. According to NASA's OIG, Artemis acceptable crew mortality rate is 1 in 30. Roughly 3x riskier than the shuttle. There genuinely i…
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Do actual science. Send robots there, like Curiosity and Perseverance. And over all: start recognising that there is no point in sending humans to Mars other than "uh uh it's cool we sent someone there and they came back alive". I have nothing against the fact that it is cool. And I watched Artemis enthusiastically because it is really, really cool. What I hate is when people seem to be so sure that this is "the new…
> start recognising that there is no point in sending humans to Mars Fair point but if you want to inspire other humans you need to send humans not robots.
Do you really think that the job is completely different for workers between building a rocket sending a robot and building a rocket sending humans? Do you think that it was easy to send Curiosity or Rosetta, and that the employees found it boring?
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> start recognising that there is no point in sending humans to Mars Fair point but if you want to inspire other humans you need to send humans not robots.
I disagree. Look at how many people work in robotics versus how many people are astronauts... Do you really think that the job is completely different for workers between building a rocket sending a robot and building a rocket sending humans? Do you think that it was easy to send Curiosity or Rosetta, and that the employees found it boring?
We need both.
I had to explain to my wife and kids (not that I'm in this field, but I also have to remind myself) that we are able to pinpoint where the craft will land, when it will land down to the minute, because of ... just ... math. And we're able to get them there and back because of science. It all boils down to equations that describe the world accurately, and a way of experimentation, iteration, thinking that gets us all…
I'd add a caveat to this. We can do this because of war. We know where it will land accurately because that maths and physics has been sharpened with butt loads of data. Even the reentry blackout has links to war in Plasma Stealth[0]. That data was mostly obtained because we want to know where our ICBM warheads will land. And where the enemies ICBM warheads will land so we can work on the problem of shooting them dow…
Kinzhal is just an air-launched version of Iskander with a bit better energetics because of not launching stationary from the ground. It's not a magic superweapon.
Its terminal manoeuvring is hardly new, Pershing II was doing that back in the 70s.
The top speed of a ballistic missile (that you're citing) is not the same as its speed in the interception-relevant section of the flight, because atmosphere gets denser and slows missiles down (and manoeuvring slows MARVs down even further). The Ukrainian operators claim that the observed speed was close to Mach 3.6.
The primary interceptor for the higher energy Kinzhal would be THAAD, not PAC-3. Sadly, Ukraine didn't get THAAD.
"Plasma stealth" is a sci-fi fabrication. The US had no problem tracking ICBM RVs with their much higher speeds close enough for a direct hit during a Sprint test back in the 70s.
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Jared? Sounds familiar, is it a friend of yours? If yes should you not disclose it? The casual first name use basis is a tell. You wouldn't say "glad Bill is cooking something up" about Gates. This kind of parasocial familiarity with billionaires is how PR becomes indistinguishable from fan fiction. Isaacman is a space tourist, not an astronaut. He is the CEO of Shift4 Payments, which processes payments for SpaceX. M…
Almost everything you said is false, but to pick on a couple of issues, on Polaris Dawn he did the same tests and reported results just like the spacesuit engineer that flew with him to test the spacesuits in space. That transparent review was enough to convince skeptical experts, journalists and the astronauts that the issues were understood and the work arounds adequate. I think your projection is the beam in your…
You claim the Artemis II review convinced skeptical experts.What actually happened was Isaacman ( or shoud I say Jared? ) convened a January meeting to present NASA rationale for flying a heat shield they already knew was flawed.
CNN was denied access, only two journalists were invited, largely off the record. Isaacman own words afterward, that the meeting "only reaffirmed my confidence", tell you the conclusion preceded the review and show a level of manipulative representation, that hint he will go far in the current administration.
The most qualified skeptic in the room, Charlie Camarda, a former NASA astronaut, heat shield research engineer, and member of the first shuttle crew to fly after Columbia, walked out unconvinced. He said NASA "definitely does not have the data to show that it's safe" and that the agency was using "the same flawed thinking and crude analysis tools, similar to Columbia, similar to Challenger." He wrote an open letter to Isaacman warning that this "exhibits the same patterns that preceded past catastrophes." He estimated 1-in-20 odds of disaster. Danny Olivas was a man on the payroll, Charlie Camarda no.
On Polaris Dawn you say Isaacman, did the same tests and reported results just like the spacesuit engineer. You are making my point for me. The spacesuit engineer was Sarah Gillis, a Lead Space Operations Engineer at SpaceX who spent 11 years training astronauts, including the NASA crews for Demo-2 and Crew-1. She was there because she helped build and develop what was being tested. Isaacman was there because he paid for the mission.
Following test procedures that SpaceX engineers wrote, on hardware SpaceX engineers designed, inside a spacecraft SpaceX engineers built, does not make you an engineer. It makes you a test subject with a checkbook. A patient in a clinical drug trial also "does the same tests and reports results" as the researchers but that does not qualify them to run the FDA.
Which brings us to the question you seem to have avoided.
Why was Isaacman selected as NASA Administrator? He is the CEO of Shift4 Payments, which has a five year global payment processing deal with SpaceX's Starlink.
He has no aerospace engineering background, no government management experience, no science credentials. During his confirmation hearing, when Senator Markey asked about his ties to Musk, Isaacman claimed they were not close :-)) and that he had not discussed his NASA plans with Musk...
But when Markey asked whether Musk was present at his interview with Trump, a simple yes or no question... Isaacman refused to answer.
A payments CEO with financial ties to SpaceX, nominated by a president who received hundreds of millions from Musk, who can't say whether Musk was in the room when he got the job... If you don't see the problem, you either are not looking or dont want to look.
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> Doesn’t change the fact that each coin toss is still 50/50. That assumes a fair coin. The fact is you don't know what the odds were of getting heads or tails for that particular coin, all you know is that you got 3/4 heads. And in this analogy, a few hundred coins have every been made, in maybe a dozen styles, none of which have been fair, so you have no good reason to believe that this particular coin should have…
But the idea we're exploring is that the coin is fair (i.e. the 1/1000 estimate is correct, and the Apollo missions were unlucky).
We are not dealing with the tautologically true statement that we are assuming the 1/1000 estimate is correct and thus the odds are 1/1000 no matter what we measure. We are dealing with whether or not we can safely reject the hypothesis that the true odds are 1/1000 based on the actual observation of 1/12.
Billions of coins have been minted, and flipped a countless number of times, and we can do the physical analysis of coins such that we know the odds of a coin not being fair, without deliberate intervention to make them such, are astronomically low. As such no one is going to reject the hypothesis that a coin is fair based off of a small number of coin tosses. Hell even if you got 10 heads in a row, while the odds of that sequence is 1 in 1024, we would probably conclude it was luck rather than that the coin was flawed.
For spaceships on the other hand, those priors don't exist. We need to look at just the data from this particular test. The odds of a 1/1000 event occurring in the first 12 attempts is 1 in 84. For rejecting the hypothesis that a mass produced coin is fair, those odds aren't bad; but for rejecting the null hypothesis that the apollo capsules were just unlucky it's way over the reasonable threshold.
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I disagree. Look at how many people work in robotics versus how many people are astronauts... Do you really think that the job is completely different for workers between building a rocket sending a robot and building a rocket sending humans? Do you think that it was easy to send Curiosity or Rosetta, and that the employees found it boring?
A robot travelling on moon or mars is not the same thing as a man walking on moon or mars. We need both.
What for?
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A robot travelling on moon or mars is not the same thing as a man walking on moon or mars. We need both.
> We need both. What for?
Human missions drive public interest and funding. A human putting a country's flag is 1000 time better than a rover putting a country's flag.