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Water found on a potentially life-friendly alien planet

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

#93

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...

Or we could shift to an other side of the universe by "inverting" the mass of the ship where the speed of light is much higher[1].

Cosmology is so cool... too bad we do not have time for that: we cannot even cure the common cold!

[1]: https://januscosmologicalmodel.com/pdf/2014-ModPhysLettA.pdf Cosmological bimetric model with interacting positive andnegative masses and two different speeds of light,in agreement with the observed acceleration of the Universe

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

#94
post #74

I say let's go. Now, whether you believe it or not, it is a fact that the US government has acquired alien technology and yet continues to keep it hidden by being stuck in a cold war mindset of, "well, we can't let the Chinese or Russians get their hands on this". That is the ultimate expression of narrow thinking, especially when there is a whole universe out there! Bring on the downvotes but history will vindicate…

Evidence?

The government has been studying UFO's at the highest levels since at least 1947 and likely prior. You don't study something closely for 7 decades and not learn anything.

https://www.cia.gov/library/center-for-the-study-of-intellig...

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

#95
post #4

Earlier quoted context omitted.

It's 111 light years away. For all intents and purposes, that's a one way trip right there; irregardless of the rocket equation. Even at relativistic speeds, you can't come home anymore.

But that's assuming you're traveling at the speed of light, right? In reality it would take much much longer than 111 years.

The fastest man-made object: https://en.wikipedia.org/wiki/Parker_Solar_Probe

Travelling at that speed (0,00064c - no relativistic effects) would take ~170,000 years.

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

#96

Earlier quoted context omitted.

You can make the trip arbitrarily small from your perspective (in theory at least :) ). The issue is that by the time you've made it back home, it's 222 years later. Hence "you can't go home anymore". :)

If you put some money in an interest-bearing account you could at least buy a new home when you got back.

Or maybe a meal at a nice restaurant?

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

#97
post #21
post #4

Earlier quoted context omitted.

It's 111 light years away. For all intents and purposes, that's a one way trip right there; irregardless of the rocket equation. Even at relativistic speeds, you can't come home anymore.

The fastest spacecraft humans have produced is the Parker Solar Probe which when it zips around the sun will reach 430,000 mph. At that speed it would take 173,000 years to reach this planet.

It is also the slowest spacecraft. Speed is relative. To get it going that 'fast' when close to the sun the other half of its orbit is correspondingly slower than earth. When launched it accelerated away from earth at speed, but from the perspective of the sun is was actually decelerating, and was moving much slower that it was when attached to the earth.

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

#98
post #43
post #30

Earlier quoted context omitted.

Great! , do that gravity assist a few more hundred times around the sun and we are there in 500 years.

You can't do a gravity assist around the sun once you've reached solar escape velocity, because you won't be visiting the sun again. If we could pull that trick so easily, we already would have.

Well... you could wrap around another star, or two, and come back to this sun for another assist a la Rendezvous with Rama.

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

#99
post #92

Isn't it odd to think that one day, there will be a top post on Hacker News: "Alien Life Discovered on Nearby Planet (430 points)".

One would like to think that it would get more points than that :-)

But if it gets more than 430, it will have 430 at some point.

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

#100
post #71

Earlier quoted context omitted.

Theoretically, you can. At 0.99c 111 light years take about 15 years of ship time to travel.

Which would put you in your 50s to 60s if all you did was go there and back.

And? Seems unlikely that we would send a small number of people on a 30 year trip. Given 30 years in a tin can with little to do, I'd expect the age range on departure to be ~18+ (with some people knowingly making a one way trip), and the age range on arrival back at Earth to be 0+, due to new additions to the crew mid-flight.
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