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Water found on a potentially life-friendly alien planet

nationalgeographic.com

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Re: Water found on a potentially life-friendly alien planet

#241

Post by temporalparts »

tunesmith wrote: post #204

I got into the Wait Calculation[1] a few weeks back and made a Jupyter notebook out of it. At our current max speed (692,000 km/hr, stated max speed of Parker Space Probe), it would take about 173,000 years to get to that planet. We could instead choose to Wait and grow our tech. By picking a constant annual growth rate and then doing some calculus to find the minimum, we can calculate the shortest possible time it w…

Does this take into consideration that your mass increases as you travel closer to the speed of light?

Re: Water found on a potentially life-friendly alien planet

#242

Post by gisely »

vermilingua wrote: post #238
narrator wrote: post #230

Earlier quoted context omitted.

Progress in physics was much faster in the early 20th century when it wasn't so fascinated with deep space. Yes, you needed to observe eclipses to verify relativity, but that was a tool, not the end in itself. Cosmology involves distances that are so great that it seems like it's pouring a whole bunch of smart people's efforts down the drain in an ultimately futile waste of brain power that will never amount to anyth…

> when we get faster than light travel FTL requires numerous things to be true about our universe, that all signs say are not.

The speed of light is just a compute constraint imposed on the physics simulation that is our universe. If we can just get the gods who are running that simulation to give us a little extra compute time in our neck of to woods then we can all be galactic explorers.

Re: Water found on a potentially life-friendly alien planet

#243

Post by dodobirdlord »

solipsism wrote: post #199
saagarjha wrote: post #193

Earlier quoted context omitted.

The point is finding planets aside from our own .

Sometimes N=2 is extremely different from N=1. Specifically when we have N=1 and we suspect that it might be unique, or extremely rare to the point that you wouldn't expect to find instances. Sometimes N=2 is not that different from N=1 though. Specifically when you don't think the situation is necessarily that rare, you just don't have a big population to choose from. That's the situation here. Astronomers expect to…

In this case N=2 is very different from N=1. The probability of detecting further Earth-like planets is not influenced by the existence of Earth, because what we're actually measuring is the conditional probability of detecting Earth-like planets given the existence of Earth, which already factors Earth in. In this case N=1 is a lot more like N=0 and N=2 is a lot more like N=1.

Re: Water found on a potentially life-friendly alien planet

#244

Post by solipsism »

dodobirdlord wrote: post #243
solipsism wrote: post #199

Earlier quoted context omitted.

Sometimes N=2 is extremely different from N=1. Specifically when we have N=1 and we suspect that it might be unique, or extremely rare to the point that you wouldn't expect to find instances. Sometimes N=2 is not that different from N=1 though. Specifically when you don't think the situation is necessarily that rare, you just don't have a big population to choose from. That's the situation here. Astronomers expect to…

In this case N=2 is very different from N=1. The probability of detecting further Earth-like planets is not influenced by the existence of Earth, because what we're actually measuring is the conditional probability of detecting Earth-like planets given the existence of Earth, which already factors Earth in. In this case N=1 is a lot more like N=0 and N=2 is a lot more like N=1.

That's silly. The type of world we're interested in is ones that could support life as we know it. We knew one of those exists. We're trying to find more.

Re: Water found on a potentially life-friendly alien planet

#245

Post by gremlinsinc »

lachlan-sneff wrote: post #213
ryacko wrote: post #206

Earlier quoted context omitted.

If we can simulate wetware perfectly, we would also be able to solve any health condition. This is all presumptive of the preferences of individual humans. It may be that the giant extrasolar Earth-type planets could be dismantled and rebuilt into smaller Earths located at various Lagrange points.

For sure, maybe future humans won't want to do that. The important takeaway is that they'll have the opportunity to do so if they wish. They could even clone them back on the other end and install the preexisting mind, basically teleportation.

You're assuming that we'll have a means to send data across Galaxy faster than the speed of light. If not then it'll take 111 years to upload your mind.

Re: Water found on a potentially life-friendly alien planet

#246

Post by vermilingua »

gisely wrote: post #242
vermilingua wrote: post #238

Earlier quoted context omitted.

> when we get faster than light travel FTL requires numerous things to be true about our universe, that all signs say are not.

The speed of light is just a compute constraint imposed on the physics simulation that is our universe. If we can just get the gods who are running that simulation to give us a little extra compute time in our neck of to woods then we can all be galactic explorers.

Just for the sake of argument, let's run with that.

If we're in a physics simulation, we don't experience at the rate that the simulation is processed. One "tick" of the simulation could be processed in one second of the host universe, or one hour: and we wouldn't feel the difference. We are processed at the same tickrate as the rest of the universe, so we experience the passage of time at the same rate that the simulation flows.

The speed of light isn't just the speed of light, it's the speed of causality. It just so happens that light moves pretty well at that "speed limit" (in a vacuum). We could ask our computational hosts to increase or decrease c, and we still wouldn't be able to travel any faster than it.

Re: Water found on a potentially life-friendly alien planet

#247

Post by [deleted] »

nothis wrote: post #173
transreal wrote: post #2

With a planet this large, visiting it would be a one way trip due to the "The Tyranny of the Rocket Equation" [0]. I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). [0] - https://www.nasa.gov/mission_pages/station/expeditions/exped...

> I'm looking forward to the day we start finding exo-planets that are closer to Earth in size and which could potentially have space-faring races (and which we could leave if we were ever to visit them). I just realized I have no real concept of how many stars there even are within, say, a 100 light year radius of our sun (I guess that's a more realistic thing to find out than the number of planets). A quick search…

[deleted]

Re: Water found on a potentially life-friendly alien planet

#249

Post by petre »

manicdee wrote: post #134

Some caveats per Marina Koren https://twitter.com/marinakoren/status/1171873631808438273 1. This planet probably doesn’t have a solid surface 2. Being in the “habitable zone” doesn’t mean a planet is habitable 3. The detection is of water molecules, chances are the water only exists as vapour in the atmosphere of this small gas giant. 4. If you ask 10 astronomers about this you will get 11 opinions

It isn't habitable even if it's a super Earth because the gravity would be 8g if it's 8x the mass of Earth.

Re: Water found on a potentially life-friendly alien planet

#250

Post by jaco8 »

Swizec wrote: post #239
jackvalentine wrote: post #225

Earlier quoted context omitted.

You'd have to form some kind of trust, the "Swizec is in space for 200 years trust" to handle your investments for you with a constitution that lays out how long it is expected for you to be gone. You might come back to discover that after several generations without oversight your trust has invested in bombing children and enriching the fund managers. I dunno.

You still get in trouble I think. Have any political regimes been stable enough in the past 222 yaers for the trust to survive? All of Europe has gone through multiple revolutions, USA was only 30 years old back then so you wouldn’t have considered it ... that leaves what, the UK? Any parts of Asia that survived since 1797?

With travel time that long , you have to consider technological advancement at home. Just imagine that you look out of your window after travelling for 70 years and there is this other ship overtaking yours with ease.
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