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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

#271

Post by blencdr »

skrebbel wrote: post #267
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…

As a startup founder, I learned the hard way to not assume progress will ever be exponential.

As a guy who lives in a finite world where energy comes mainly from fossil fue in a way or another, I do not assume that any constant progress in energy supply is something achievable.

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

#272

Post by [deleted] »

SRTP wrote: post #268
ddingus wrote: post #257

Earlier quoted context omitted.

I am reading big space operas right now. What we know of this reality is so limiting compared to what we can imagine. Good dreams. Many of us have them. I also like to dream the knowable remains much larger than the currently understood too.

Any book in particular you'd recommend?

[deleted]

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

#273

Post by Jorge1o1 »

SRTP wrote: post #268
ddingus wrote: post #257

Earlier quoted context omitted.

I am reading big space operas right now. What we know of this reality is so limiting compared to what we can imagine. Good dreams. Many of us have them. I also like to dream the knowable remains much larger than the currently understood too.

Any book in particular you'd recommend?

The Baen Free CD has always been a great source of free sci fi books for me

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

#274

Post by tachyonbeam »

blencdr wrote: post #271
skrebbel wrote: post #267

Earlier quoted context omitted.

As a startup founder, I learned the hard way to not assume progress will ever be exponential.

As a guy who lives in a finite world where energy comes mainly from fossil fue in a way or another, I do not assume that any constant progress in energy supply is something achievable.

No, and traveling near lightspeed is likely hardly possible. However, fusion will likely become a reality within our lifetimes, and if we can build fusion powered spaceships, we could likely reach a fraction of the speed of light, say, 0.2c. I don't think it's that crazy to think we could do that a few centuries from now. That still means it would take over 1000 years to reach that planet.

Personally, I think that if humanity progresses that far technologically, without destroying itself, we probably won't care that much about habitable planets or planets with water. We'll just live in space and harvest the energy and resources that are available nearby. There are a lot of other planets much closer to us than K2-18b. We could just build bases in orbit around those stars, harvest asteroids for minerals and hydrogen for fusion power.

Alpha Centauri would "only" take 22 years to reach at 0.2c (plus some time for acceleration and deceleration). You could leave earth and live to see that solar system, and you could travel there on a ship that is basically a large city that will just park itself in orbit around the star on arrival, acquire resources, and start building something bigger.

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

#275

Post by vermilingua »

SRTP wrote: post #268
ddingus wrote: post #257

Earlier quoted context omitted.

I am reading big space operas right now. What we know of this reality is so limiting compared to what we can imagine. Good dreams. Many of us have them. I also like to dream the knowable remains much larger than the currently understood too.

Any book in particular you'd recommend?

Anything in the Culture series by Iain M. Banks;

The Expanse series by James S. A. Corey;

The Commonwealth and Void trilogies by Peter F. Hamilton, and the Night’s Dawn trilogy also by Peter F. Hamilton;

The Dune saga by Frank Herbert.

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

#276

Post by tunesmith »

skrebbel wrote: post #267
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…

As a startup founder, I learned the hard way to not assume progress will ever be exponential.

Over any timeframe, the rate of progress between the beginning and ending of the timeframe can be phrased as exponential for some exponent. It's just a matter of accurately estimating what that exponent is.

I take your point though - hypergrowth cannot be sustained - and estimating that exponent is fairly valueless if volatility is too high. This is all just math fun that won't be valuable if we bump along for hundreds of years and then all of sudden make a massive discovery.

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

#277

Post by tunesmith »

quickthrower2 wrote: post #265
tunesmith wrote: post #264

Earlier quoted context omitted.

No, it assumes you start and end at whatever that maximum velocity is that we've been able to achieve. That'd be fun to add, though. I'm not really sure what human-safe acceleration is - people here assume it's in the 1g-3g range. (That seems like a lot to me though, particularly for a long period of time - I think anything more than a fraction of g would be wildly uncomfortable.)

Wouldn't 1g be perfect? I've been enjoying it for a few years now on this planet.

I took it as 1g of acceleration. I don't know. Wouldn't plain old 1g mean no acceleration at all?

Edit: Oh... I guess not. :) I got confused with the extra g's we'd need to escape earth, but that's so short-term that it can be ignored. Yeah, I think 1g would be perfect.

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

#278

Post by radeklew »

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…

As others have said, E=mv^2/2 only holds at very small fractions of the speed of light. I believe the equation you need is E=mc^2/sqrt(1-v^2/c^2)-mv^2.

https://en.wikipedia.org/wiki/Kinetic_energy#Relativistic_ki...

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

#279

Post by ddeck »

vermilingua wrote: post #275
SRTP wrote: post #268

Earlier quoted context omitted.

Any book in particular you'd recommend?

Anything in the Culture series by Iain M. Banks; The Expanse series by James S. A. Corey; The Commonwealth and Void trilogies by Peter F. Hamilton, and the Night’s Dawn trilogy also by Peter F. Hamilton; The Dune saga by Frank Herbert.

I'll add the Ancillary (Imperial Radch) series by Ann Leckie to these good suggestions.

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

#280

Post by SirHound »

vermilingua wrote: post #275
SRTP wrote: post #268

Earlier quoted context omitted.

Any book in particular you'd recommend?

Anything in the Culture series by Iain M. Banks; The Expanse series by James S. A. Corey; The Commonwealth and Void trilogies by Peter F. Hamilton, and the Night’s Dawn trilogy also by Peter F. Hamilton; The Dune saga by Frank Herbert.

Hamilton’s The Reality Dysfunction was the stupidest book I’ve ever read and took hundreds of pages to expose itself. Are his others any more grounded (like your other suggestions)?
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