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Perseverance Rover lands on Mars [video]

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Re: Perseverance Rover lands on Mars [video]

#501

Post by nickik »

L_226 wrote: post #396
jws wrote: post #344

Earlier quoted context omitted.

Early starships got me thinking: given the high likelihood of a failed starship landing, and maybe having the ability to send one before fully engineering a payload… What would you ballast a starship with for the practice missions? Useful materials which might survive a RUD and aim for someplace near a likely landing zone? If you crash the parts of a milling machine, a lathe, some tooling, some assorted metals stock,…

Soil? Though not sure it is prudent to potentially spread active biological material all over a pristine (eco)system.

Mars soil is usable for plants. Or should be at least. So no need to bring soil from earth.

Re: Perseverance Rover lands on Mars [video]

#502

Post by [deleted] »

thiht wrote: post #484
mulmen wrote: post #462

Earlier quoted context omitted.

It's not really identical though. Like I said, Fahrenheit is higher resolution at these scales so that is an advantage. It doesn't mean everyone should convert to F. Just that both systems have benefits. If I changed my perception of the world to C I wouldn't actually gain anything, personally, in the context of weather and HVAC. If I need to take measurements while boiling water or making ice then I would probably u…

It's exactly the same. The perception you have on Fahrenheit is exactly the same anyone using Celsius have, with multiples of 5 instead of 10

[deleted]

Re: Perseverance Rover lands on Mars [video]

#503

Post by mulmen »

thiht wrote: post #484
mulmen wrote: post #462

Earlier quoted context omitted.

It's not really identical though. Like I said, Fahrenheit is higher resolution at these scales so that is an advantage. It doesn't mean everyone should convert to F. Just that both systems have benefits. If I changed my perception of the world to C I wouldn't actually gain anything, personally, in the context of weather and HVAC. If I need to take measurements while boiling water or making ice then I would probably u…

It's exactly the same. The perception you have on Fahrenheit is exactly the same anyone using Celsius have, with multiples of 5 instead of 10

Five is not equal to ten so no, it is not the same. That's the entire point.

Re: Perseverance Rover lands on Mars [video]

#504

Post by mulmen »

bernulli wrote: post #489
mulmen wrote: post #465

Earlier quoted context omitted.

> But one of the systems does have an advantage because it stays in base 10, whereas the other doesn't. That's a benefit to humans, not to hardware, which was the context in which I was speaking. > But you can't if you just use the `intuitive unit', and that's the whole problem. How would you measure the amount of liquid fuel in, say, the small tank for an attitude control thruster of some probe? How does that add to…

Frankly, I can't even tell if you're just being sarcastic at this point.

I'm not being sarcastic.

I have gone much farther here than I normally would. I don't think I can constructively explain this to you any further.

Re: Perseverance Rover lands on Mars [video]

#506

Post by yellowapple »

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.

> If this caused transport failures, mass starvation could follow.

The good news is that a substantial chunk of the world's cargo transportation runs on diesel (or other combustion setups similarly not reliant on electronics), so in a pinch it could probably keep going. Same with agricultural machinery. Might need to replace or refurbish some ECUs, but I'm sure there are enough clever mechanics out there willing and able to bypass those in an emergency that we'd be back up and running pretty quick on that front.

ICE 1, electric 0 ;)

It's refrigeration that'd have me more concerned, since pretty much all modern refrigeration is electrically powered (last I checked). Diesel generators might come in clutch there, assuming the refrigeration units themselves don't rely on any fancy electronics.

Re: Perseverance Rover lands on Mars [video]

#507

Post by interestica »

SethTro wrote: post #481
interestica wrote: post #241

Earlier quoted context omitted.

NASA is making the raw images of everything available: https://mars.nasa.gov/mars2020/multimedia/raw-images/

You can see what this page looked like for Curiousity at https://mars.nasa.gov/msl/multimedia/images/?page=0&per_page... Can't wait till they start posting raw images :)

Thanks for that! I just found this especially awesome shot of Curiosity: https://mars.nasa.gov/resources/21929/curiositys-dusty-selfi...

It's very high res. You can see the holes/damage on the wheels -- Perseverance will have new wheels because of it. And also, won't have the 'morse code spelling' on the wheels either. It's amazing that this kind of damage/wear couldn't have been predicted in tests. The amount of dust that has settled on top in what appears to be predictable channels is also interesting.

Looks like they have more than 300 000 images on the raw site: https://mars.nasa.gov/msl/multimedia/raw-images/?order=sol+d...

Re: Perseverance Rover lands on Mars [video]

#508

Post by lmm »

mulmen wrote: post #389
lmm wrote: post #385

Earlier quoted context omitted.

> Do you mean checking conversion between meters and kilometers? Because sure, that’s easier but you could just do everything in meters instead and not run the risk of crashing a spacecraft because of unnecessary conversions or bad assumptions. But you'll have small distances and large distances and pieces from external sources who use measurements on a scale that makes sense to them. You can make your external sourc…

My bicycle doesn’t even have a speedometer so I’m not sure how the metric system is supposed to expand my world. I’m happy looking around and glancing at my watch. Miles per hour is literally a measure of distance over time. If I wanted to use my GPS I could very easily determine how far I can go in a given amount of time. I can do this equally well in the metric or imperial systems, without converting to feet or met…

Do you never ride somewhere where you don't know how far apart everything is beforehand? I can eyeball 100/200/300m and add those up into km. I could probably learn to eyeball 100/200/300 yards, but forget relating that to miles.

Re: Perseverance Rover lands on Mars [video]

#509

Post by thiht »

mulmen wrote: post #503
thiht wrote: post #484

Earlier quoted context omitted.

It's exactly the same. The perception you have on Fahrenheit is exactly the same anyone using Celsius have, with multiples of 5 instead of 10

Five is not equal to ten so no, it is not the same. That's the entire point.

Right.

Re: Perseverance Rover lands on Mars [video]

#510

Post by koheripbal »

DowsingSpoon wrote: post #405
cdelsolar wrote: post #357

Earlier quoted context omitted.

we are very screwed if they find life on Mars. It means life is incredibly common and thus the Great Filter theory is true and we only have a few years left as a species most likely.

Disagree. If there is a filter at all then it could easily be that we’ve already passed it. Maybe the filter is the formation of multicellular life, for example. Also, Earth and Mars have exchanged a lot of material. If we find Mars life, it would not at all be surprising to learn it is related to Earth life.

It's hard to imagine that the change from unicellular life to multicellular life is a great filter. Even single cell life has evolved to crazy complexity that blurs the lines between single and multicellular life.

> If we find Mars life, it would not at all be surprising to learn it is related to Earth life.

If it's DNA/RNA based, we might actually be able to determine the relationship and whether that's true or not.

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