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NASA says distant exoplanet could have rare water ocean, possible hint of life

theguardian.com

121–130 of 156 posts

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#121

Earlier quoted context omitted.

I don't think Russia gained materially from that. While they ruthlessly exploited whatever resources they could get hold of in the Donbas, that of course that leaves the region much poorer so the have just concentrated wealth, not creates more of it overall.

I thought Crimea was about warm water ports?

I'm not sure how important the physical ports were, if they were important I suspect it mainly their symbolic importance.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#122

Earlier quoted context omitted.

""" Time dilation is the difference in elapsed time as measured by two clocks, either due to a relative velocity between them (special relativity) or due to a difference in gravitational potential between their locations (general relativity). When unspecified, "time dilation" usually refers to the effect due to velocity. """ https://en.wikipedia.org/wiki/Time_dilation

wow thanks! this was super fun, do you happen to have some souce about the calculations that go into determining the time dilation based on different velocity? i'm aware about black holes being capable of well, doing time dilation thingy due to their massive gravitational force but nothing else. edit: souce as in something a regular average joe can make sense of haha

Well, depending on your preferred format there's a great book called A Brief History of Time - https://en.wikipedia.org/wiki/A_Brief_History_of_Time , or lots of videos about it at https://www.youtube.com/results?search_query=time+dilation

More broadly, the series Cosmos with Carl Sagan was excellent, and is worth a view. The bit about time dilation is at https://www.youtube.com/watch?v=kWgEzxi_A0w . The more recent one with Neil Degrasse Tyson is also good (but while I enjoy both, I think I prefer the older one)

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#123
post #61

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway. 2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (as…

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Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#124
post #61

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway. 2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (as…

> Perhaps we could retaliate and send something back, but probably the odds are bad.

Only took 60 years from first flight to man on the moon.

300 years is plenty long time.

Suppose we crack true general artificial intelligence, nuclear fusion, ability to design self-assembling beings with DNA compilers, advanced material synthesis then we could very well launch a retaliating attack.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#125

Earlier quoted context omitted.

To ensure that we don’t do the same.

"They might be hostile. So lets send an army of robots to wipe them out." But if the army of robots fails, then they'll definitely be hostile. That's... putting a lot of trust in your robots to win when faced with completely unknown conditions.

the dark forest requires a relatively simple cheap and effective way of sterilizing a stat system. if there is an easy way to do that then a first strike becomes a more reasonable first contract option.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#126

Earlier quoted context omitted.

If they are used to propaganda where every enemy is stupid and ever allied plan works they don't. But in real life you can be genius and a bad person at the same time

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Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#127
post #124
post #61

1. I looked up the phase diagram of water. If the mass is 10 times the earth, their athmospheric pressure might be one hundred times of ours. At that pressure, water boils at about 300°C. If ambient temperature is about 200°C then their chemistry would be completely incompatible with ours. And with hydrogen athmosphere anyway. 2. Re the Dark Forest hypothesis: maybe. They will discover our radio in about 60 years (as…

> Perhaps we could retaliate and send something back, but probably the odds are bad. Only took 60 years from first flight to man on the moon. 300 years is plenty long time. Suppose we crack true general artificial intelligence, nuclear fusion, ability to design self-assembling beings with DNA compilers, advanced material synthesis then we could very well launch a retaliating attack.

In principle yes, it is enough time, however it is important not to underestimate our novel hostility to doing anything both meaningful and new.

Re: NASA says distant exoplanet could have rare water ocean, possible hint of life

#130

Earlier quoted context omitted.

"They might be hostile. So lets send an army of robots to wipe them out." But if the army of robots fails, then they'll definitely be hostile. That's... putting a lot of trust in your robots to win when faced with completely unknown conditions.

the dark forest requires a relatively simple cheap and effective way of sterilizing a stat system. if there is an easy way to do that then a first strike becomes a more reasonable first contract option.

Hopefully there is no way to drop a contaminant into a star to affect its output. A +/-10% change in brightness over a sustained period would probably neutralize us.
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