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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

#221

Post by dylan604 »

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 you would need to start slowing down halfway there?

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

#224

Post by jacobsenscott »

not_a_cop75 wrote: post #151
chenning wrote: post #115

A very quick search suggests that earth will become uninhabitable somewhere between 500 million and 2 billion years from now. If we shot a probe to this life-friendly alien planet with some sort of primordial soup, even traveling at the speed of light it would take 4 billion earth years to get there. Do I have that right? Basically we'll never even come close to being around when it finally arrives, if it ever arrive…

It seems like it would be much easier to terraform the real estate around us than try to opt for something 100 light years away. Mars has a leaky atmosphere - sure it's a real fixer upper. But we have a better chance of fixing it, or even correcting the orbit of our planet so that in 500 million years it's still livable.

Even easier is to stop digging stuff up and burning it. But we can't even do that.

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

#225

Post by jackvalentine »

Swizec wrote: post #218
peteretep wrote: post #180

Earlier quoted context omitted.

I mean that sounds pretty awesome if you invested your funds well. I'd definitely be willing to be the first person who did that.

Where can you invest that would still recognize those funds as yours after 222 years?

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.

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

#226

Post by nealabq »

Thrymr wrote: post #186
vonmoltke wrote: post #163

Earlier quoted context omitted.

A constant acceleration of 1g would cause the ship to hit c in about one ship year.

The ship will never hit c .

If the ship travels tens of billions of light years will it eventually be traveling away from it's starting point at greater than c due to the dark-energy expansion of space itself? Or will the ship just red-shift more and more but never disappear from an observer with a very good telescope who stayed home?

And what if you drove your ship straight into a super-massive black hole?

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

#227

Post by [deleted] »

Simon_says wrote: post #210
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…

> taking the square root to get velocity growth rate This is your mistake. It's an approximation that works well only at low speeds.

[deleted]

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

#228

Post by [deleted] »

brownbat wrote: post #220
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

> Being in the “habitable zone” doesn’t mean a planet is habitable True. Being a spooky near twin of Earth isn't necessarily enough. The air inside popcorn factories is basically identical to the Earth's atmosphere, but breathing in diacetyl, a butter flavor you'll find in that air, will kill you a few months or years later. Popcorn lung really undermined my naive view that we would one day be able to run a scan or a…

[deleted]

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

#229

Post by [deleted] »

dylan604 wrote: post #221
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 you would need to start slowing down halfway there?

[deleted]

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

#230

Post by narrator »

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…

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 anything much at all. Besides, when we get faster than light travel we can just pick up exoplanet research where we left off and it will actually be practical and probably far more efficient with the computers and such we will have developed by then.

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