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Perseverance Rover lands on Mars [video]

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Re: Perseverance Rover lands on Mars [video]

#411

Post by darkwater »

azernik wrote: post #259
twic wrote: post #216

Earlier quoted context omitted.

> Cruise Mass Balance Devices They put those in to make the probe seem higher-quality. They got the idea from Beats headphones.

We were doing that at Meraki back in the early 2010s (it turned out they were also useful as a heat sink and, because the metal was exposed to air, a radiator). Pretty sure Meraki got the idea from some Apple product or other.

Speaking of Meraki, I had an awful experience with those devices. Basically we were in building with TONS of other wifi networks around and Meraki network just went crazy from time to time until we fine tune it down to the channel for each AP. I mean, for something you pay $$$ to buy the devices and $$$ each month for the subscription is a pretty poor experience.

Re: Perseverance Rover lands on Mars [video]

#412

Post by natosaichek »

Koshkin wrote: post #327
natosaichek wrote: post #279

Earlier quoted context omitted.

The human retina is composed of cells that are responsive to different wavelengths of light. Color is the word that we use to describe the subjective sensations associated with certain patterns of stimulation of those cells. There is no "yellowness" in a bananna. We cannot construct an instrument capable of measuring "yellow" as such. What we can measure are the intensities of wavelengths of light. We can notice that…

> We cannot construct an instrument capable of measuring "yellow" as such. Of course we can. We can capture the signal sent through the optical nerve and then reproduce it as a stimulus which will make the brain “see” yellow color. Besides, humans are capable of distinguishing literally millions of colors, of which just a tiny fraction can be attributed to measuring particular wavelengths (or, more accurately, partic…

Well, the instrument wouldn't me measuring yellowness... it would be measuring electrical impulses that (in some individuals) correspond to the (verbally asserted) perception of "yellow". "Yellow" is not a characteristic of the world; it's a convenient label that humans apply to some bucketed sets of sensory perceptions.

I agree that there are sensory perceptions humans are capable of perceiving and labeling as colors that cannot be attributed to external physical phenomena, but those are largely artifacts of the way our brain processes signals. For example if you stare at a purple dot for some time, then look away, you'll perceive a yellow dot where there is no external set of photons corresponding to the wavelengths that normally trigger the sensation of yellow striking your retina.

This is just more explanation about how "yellowness" is a characteristic of our brains, not of the external world.

Or did you mean something other than what I'm referring to here? I think that for the vast bulk of humans, the vast bulk of the colors they perceive regularly are due to photons striking rods and cones in their eyes at various intensities, causing color sensations to occur in the brain. Do you think something else is happening?

You seem to understand how the eye works, and some neuroscience, so I don't understand how you can have the questions that you raise about whether we can build cameras that sense "color" instead of "light"

Re: Perseverance Rover lands on Mars [video]

#413

Post by saagarjha »

mongol wrote: post #390
JohnJamesRambo wrote: post #361

Earlier quoted context omitted.

I find it extremely hard to believe you could kill every human being on earth at this point. We’ve reached critical mass, we aren’t going anywhere. When we had that few thousand individuals population bottleneck in the past was when it was dicey. What sort of event could kill every human and end our species? I can only think of planet-wide extinction events like massive asteroid impacts that sterilized the whole eart…

I wonder what a huge Carrington solar storm would do to humanity. If electricity went out everywhere, transformers burned up all over, electronics fried. If this caused transport failures, mass starvation could follow. I really hope a severe solar storm would not be as bad as that and hopefully someone could enlighten me on this.

Killing literally every single human being is not easy. Sure, killing off half of humanity is pretty easy to conceive, but to kill all of humanity it takes a lot more work.

Re: Perseverance Rover lands on Mars [video]

#414

Post by jessriedel »

stargazer-3 wrote: post #404
jessriedel wrote: post #387

Earlier quoted context omitted.

Great video! I am also surprised by the fact that they bring that much mass just to jettison. In theory they could mounted some of the useful mass on a slider/rail system to achieve the necessary adjustment to the mass distribution without dropping mass overall, but apparently it wasn't worth the complexity/volume cost. I'm sort of surprised we don't yet have ML powered "de-accent-ization". His french accent isn't ha…

I, for one, would be uncomfortable with AI removing my accent. I understand it's for other people to understand me better - and I am fine with AI-generated subtitles - but altering the way I speak would reduce the amount of "me" in ways I'm not fully ok with.

You wouldn't need to use it on videos you produce if you don't want.

Re: Perseverance Rover lands on Mars [video]

#415

Post by jessriedel »

_-___________-_ wrote: post #408
jessriedel wrote: post #387

Earlier quoted context omitted.

Great video! I am also surprised by the fact that they bring that much mass just to jettison. In theory they could mounted some of the useful mass on a slider/rail system to achieve the necessary adjustment to the mass distribution without dropping mass overall, but apparently it wasn't worth the complexity/volume cost. I'm sort of surprised we don't yet have ML powered "de-accent-ization". His french accent isn't ha…

I’m amazed that people still say things like “de-accent” as if there was such a thing as “no accent”. You are asking for a button that makes his French accent more like your own. It’s a separate thing from native vs. non-native speakers - there are plenty of native English speakers with accents that you would also find challenging.

You are reading something into my comment that wasn't there in order to pick a boring fight. There is of course no such thing as no accent a priori, but there is such a thing as "accents understood by (vastly) more people" and "accents closer to the mean accent of native speakers". When I learn Russian, my English accent is not on the same footing as a Muscovite's; the intended notion of "de-accenting" the English accent on my Russian is obvious.

Consider responding to the substance of the comment instead.

Re: Perseverance Rover lands on Mars [video]

#417

Post by jonathanstrange »

fckthisguy wrote: post #264
Daho0n wrote: post #222

Earlier quoted context omitted.

S/he already did. We just don't know yet.

You can just say "they". (Not trying to be judgy. People just seem to forget about the gender neutral use of "they".)

I'm not a native speaker but the problem I have with it is that it has the wrong numerus. Although I have done so in papers recently, because it seems to be a trend, sentences like "If a person chose option B, they were categorized as a cautious assessor" seem ungrammatical to me. (In this case it's easy to reformulate the sentence in plural and simpler, but that's not always the case and I hope you get the point.)

Re: Perseverance Rover lands on Mars [video]

#418

Post by joe_91 »

m4rtink wrote: post #324
joe_91 wrote: post #68

Earlier quoted context omitted.

Haha, good point - we'll have to come back in 4-5 years time when SpaceX have touched down on the moon and mars and check the cost. Considering their low cost & speed at getting things into orbit these days and the plans they have for starship I hope that the data will prove me right in a few years

While this timeline might be optimistic, this is what came to my mind when I heard about the current timeline for Mars sample return - samples returning back to Earth in 2031 . https://en.wikipedia.org/wiki/Mars_sample-return_mission#NAS... Like it's nice to finally have a firmer timeline for that, but damn, 10 years from now. A SpaceX employee gathering the sample tubes into his backpack in a couple years time to be…

Yes, hopefully SpaceX can do it quicker than 10 years! Considering 15 years ago they started with their first rocket and how far they've come in that time I have high hopes.

I think Elon was hoping for a manned mission to Mars in 2024 back in 2017 but his latest projection is 2026. He's certainly optimistic :)

Re: Perseverance Rover lands on Mars [video]

#419

Post by mulmen »

thiht wrote: post #407
mulmen wrote: post #401

Earlier quoted context omitted.

“Human scales” meaning temperatures that won’t burn my skin or give me frostbite. 70 is nice. 60 is cool. 50 is cold. 40 is really cold. 80 is hot. 90 is really hot. 100 is potentially dangerously hot. I guess 20.5 is nice, 15.5 is cool, 10 is cold, 4.5 is really cold, 26.5 is hot, 32 is really hot and 37.7 is dangerously hot. It’s fine if you are used to it but I don’t really see a benefit. I was in a hotel room in…

> I guess 20.5 is nice, 15.5 is cool, 10 is cold, 4.5 is really cold, 26.5 is hot, 32 is really hot and 37.7 is dangerously hot. Or, you know, 20, 15, 5, 30 and 40 instead of the arbitrary decimals you chose to use to prove your point

Sure, you can pick even numbers in either scale that are awkward decimals in the other. I just prefer the ten degree bands of the Fahrenheit scale for these ranges.

Re: Perseverance Rover lands on Mars [video]

#420

Post by lmilcin »

spaetzleesser wrote: post #345
lmilcin wrote: post #251

Earlier quoted context omitted.

Actually, NASA uses metric system internally. Imperial units are probably used for general public convenience.

Considering that one of NASA's roles is to inspire young people to enter STEM I think it would be important to promote metric as much as possible.

I don't see how the choice here can promote STEM.

Do you think kids find it sexy to talk about meters, kilograms and degrees Celcius rather than feet, miles, pounds and Fahrenheit?

I can't fault for choosing what is more understandable to the target audience.

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