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

theguardian.com

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

#111

Post by wongarsu »

shafyy wrote: post #46
sandworm101 wrote: post #37

Earlier quoted context omitted.

Many forms of life may be detectable using telescopes. A jungle planet will look different in many ways than an ice world.l, ways that are detectable. A billion LED street lamps would similarly make the night side detectable.

Well only once you get to very very close to it.

For reference, this is Pluto as seen by the Hubble Space Telescope. Until the New Horizons flyby that was our best picture, and Pluto is right here in our solar system.

https://hubblesite.org/contents/news-releases/1996/news-1996...

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

#112

Post by atkailash »

_nalply wrote: 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

#113

Post by AnimalMuppet »

pharmakom wrote: post #69
dividedbyzero wrote: post #65

Earlier quoted context omitted.

> Then they might assemble something like a robotic attack army and send it over Why would they want to though? What do we have here that someone who could do the above couldn't get much easier otherwise?

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.

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

#114

Post by daveguy »

wongarsu wrote: post #97
daveguy wrote: post #93

Earlier quoted context omitted.

[flagged]

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

[flagged]

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

#115

Post by ducharmdev »

wfhBrian wrote: post #110
_nalply wrote: 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…

> Then they might assemble something like a robotic attack army and send it over after Violence is undeniably primitive behavior. It amazes me how many humans assume that other species would advance technologically to the point of interstellar travel while still holding on to primitive roots. It's extra surprising from a community like HN where an abundance mindset is the status quo.

You're setting up a binary between advanced/primitive; I would hesitate to speculate that they would conform to our ideas of these concepts.

The other thing to consider is, we might perceive some actions as violence, while the other species may not view it at violence at all. We may simply be materials that can be reallocated for other purposes, just like how humans often view living things in our environment.

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

#116

Post by throw1234651234 »

_nalply wrote: 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…

It's a complete myth that far-away planets can pick up our radio signals from background noise (especially from our own sun). We can't even talk to the nearest star system at 4ly.

https://space.stackexchange.com/questions/22617/can-we-commu...

This misconception fuels the false "why are we alone" question that implies we would have detected intelligent life if it's there. Not so fast.

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

#117

Post by konschubert »

kawzeg wrote: post #70
melvinmelih wrote: post #62

Earlier quoted context omitted.

How does one travel 1000 light years in a span of human lifetime (~80 yrs) if you’re not going faster than the speed of light?

Time dilation! Time is relative. For an outside observer, over 1000 years pass, but aboard the ship, much less time passes. There are calculators for this, e.g. at [0]. If you constantly accelerate at 1g, flip around at the halfway point and accelerate in the opposite direction for the rest of the journey, roughly 13 years would pass from the traveler's perspective. This site also has a "Newton's universe" mode, whic…

I am pretty rusty in special relativity, but IIRC, in the ship it basically seems like the distance is contracting as you accelerate. And from earth, it seems like time is going slower inside the moving spaceship.

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

#118

Post by sandworm101 »

shafyy wrote: post #46
sandworm101 wrote: post #37

Earlier quoted context omitted.

Many forms of life may be detectable using telescopes. A jungle planet will look different in many ways than an ice world.l, ways that are detectable. A billion LED street lamps would similarly make the night side detectable.

Well only once you get to very very close to it.

Not something like the "red edge" associated with plant life.

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

#119

Post by SiempreViernes »

Retric wrote: post #96
SiempreViernes wrote: post #90

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.

A thief doesn’t care about overall economic outcomes. Crimea may be worse off but that’s not necessarily relevant to Russia’s leadership.

Sure, leadership might gain via corruption but the parent I responded to was more likely speaking of the nation as a whole and not simply leadership.

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

#120

Post by pomtato »

CalRobert wrote: post #40
pomtato wrote: post #27

Earlier quoted context omitted.

so you're implying speed atleast 10x the speed of light? i think you'll have better luck increasing the human lifespan instead.

""" 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

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