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NASA plans to launch a spacecraft to Titan

theatlantic.com

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Re: NASA plans to launch a spacecraft to Titan

#171

Post by matteuan »

eindiran wrote: post #64
magnamerc wrote: post #44

Earlier quoted context omitted.

I find it kind of funny that you think AWS will still be around in a hundred years.

This paper company was founded 771 AD: https://www.shinise.ne.jp/j_kyoto/voices/vol/48/48-d.html It's not even the longest-lived company in the world. This construction company was founded in 578 AD and continuously operated until 2006 when it was bought by a larger company: https://en.wikipedia.org/wiki/Kong%C5%8D_Gumi 100 years ago was only 1919 -- here are some random companies from 1919 that I found on Wikipedia…

The italian bank Monte dei Paschi di Siena was founded in 1624, they even use some of the centuries old building as offices...it's not doing very well but it's still there

Re: NASA plans to launch a spacecraft to Titan

#172

Post by Sharlin »

thatcherc wrote: post #142
Sharlin wrote: post #62

Earlier quoted context omitted.

No fission reaction, just radioactive decay in Dragonfly's case. It will use an RTG (radioisotope thermoelectric generator) not unlike Curiosity and most missions to the outer planets to date.

Just a note - radioactive decay is is fission, since it involves a nucleus splitting apart.

No, not quite. One of the types of radioactive decay is spontaneous fission, but it's not relevant in the context of RTGs. Alpha decay (the emission of a 4He nucleus) might in principle be called "fission" but in practice is not. Beta decay involves no splitting whatsoever.

Re: NASA plans to launch a spacecraft to Titan

#173

Post by madaxe_again »

MereInterest wrote: post #80
AnIdiotOnTheNet wrote: post #57

Earlier quoted context omitted.

Mercury's whisper thin atmosphere won't be much use for cooling anything, though possibly the surface would be. However, the real problem is that Mercury isn't actually tidally locked anyway.

You could have the facility move constantly to keep the facility straddled across the sunlight line. At the equator, this would require constantly moving at about 7 mph, though you could reduce the speed necessary by moving to higher latitudes.

To add to the vein of sci-fi novels using this idea: Inverted World by Christopher Priest. Well, similar concept but weirdified in the 1970’s fashion.

Re: NASA plans to launch a spacecraft to Titan

#174

Post by gdrift »

gene-h wrote: post #132
martinald wrote: post #92

Earlier quoted context omitted.

Why is bandwidth so scare still? Satellites in geosynchronous orbit on earth can do terabit/sec of total capacity now. Obviously latency is going to be extremely high, but I can't really understand why data rates are still so low?

Spacecraft transmit power and antenna size is limited. This means the amount of power that arrives at earth is rather low because microwaves spread out quite a bit with distance. The other issue is that NASA only has so many big radio dishes in the deep space network[0] to gather this small amount of power and extract a signal. Technology has improved, but in order to get much higher bandwidth we'd need bigger dishes…

Maybe workaround transmission power by reflecting and modulating a signal over an existing power source. Like a very big mirror with an LCD pixel in front of it.

Re: NASA plans to launch a spacecraft to Titan

#175

Post by vonmoltke »

eloff wrote: post #97
eindiran wrote: post #64

Earlier quoted context omitted.

This paper company was founded 771 AD: https://www.shinise.ne.jp/j_kyoto/voices/vol/48/48-d.html It's not even the longest-lived company in the world. This construction company was founded in 578 AD and continuously operated until 2006 when it was bought by a larger company: https://en.wikipedia.org/wiki/Kong%C5%8D_Gumi 100 years ago was only 1919 -- here are some random companies from 1919 that I found on Wikipedia…

A company lasts just 11 years on average on the S&P 500 now. Companies are surviving for shorter time periods now then they used to.

First off, what is your source for that average? This report (https://www.innosight.com/insight/creative-destruction/) has a much higher average, and forecasts a fall to 12 years by 2027.

Second, that's average time in the S&P 500 index. As noted and n the report, there are many reasons besides going under that companies drop off the index. That number doesn't really say much about longevity of the company.

Re: NASA plans to launch a spacecraft to Titan

#176

Post by TheOtherHobbes »

whatshisface wrote: post #55
sandworm101 wrote: post #33

Earlier quoted context omitted.

No. >> The Pentagon is aware of a Russian test of a nuclear-powered cruise missile but the system is still under development and had crashed in the Arctic in 2017.[17][18][19] A RAND Corporation researcher specializing in Russia said "My guess is they're not bluffing, that they've flight-tested this thing. But that's incredible." https://en.wikipedia.org/wiki/Nuclear-powered_aircraft#Russi... https://en.wikipedia.org…

Why bother? Rocket fuel is cheaper than nuclear fuel and rocket missiles can already hit anywhere.

Cheaper, easier to mass produce, doesn't need an unusually special launcher, hard to distinguish from air to air and other defensive missiles, easier to disguise the number of warheads waiting in readiness, can take an indirect/stealthy course, hard to shoot down, can include smart tracking for moving targets like carrier groups.

Re: NASA plans to launch a spacecraft to Titan

#178

Post by tfha »

eindiran wrote: post #64
magnamerc wrote: post #44

Earlier quoted context omitted.

I find it kind of funny that you think AWS will still be around in a hundred years.

This paper company was founded 771 AD: https://www.shinise.ne.jp/j_kyoto/voices/vol/48/48-d.html It's not even the longest-lived company in the world. This construction company was founded in 578 AD and continuously operated until 2006 when it was bought by a larger company: https://en.wikipedia.org/wiki/Kong%C5%8D_Gumi 100 years ago was only 1919 -- here are some random companies from 1919 that I found on Wikipedia…

AWS is different from Amazon though. AWS is a cutting edge technology in a fast moving industry that is likely to be made obsolete in the next 20 to 30 years.

Re: NASA plans to launch a spacecraft to Titan

#180

Post by dredmorbius »

newsoul2019 wrote: post #141
cookingrobot wrote: post #77

Earlier quoted context omitted.

In certain regions on Mercury the temperature stays within 1 degree of room temperature less than a meter underground. http://einstein-schrodinger.com/Mercury_temperature.pdf It’s actually relatively habitable. http://einstein-schrodinger.com/mercury_colony.html

> In fact, if we delay until the distant future, or even 50 years or so, such an effort probably will become impossible. This is because us humans will consume the Earth's non-renewable energy and mineral resources almost completely within the next 50-100 years, severely reducing our discretionary income for costly activities such as space travel. I wonder when that was written...

Likely around 2013 by the Wayback Machine.
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