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Four Earth-sized planets detected orbiting the nearest sun-like star

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Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#81

Post by glenstein »

ceejayoz wrote: post #41
baron816 wrote: post #37

Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…

Humans manage to live in the Sahara, the Himalayas, tolerate being a hundred pounds overweight fairly well, Alaskans deal with weird day/night cycles, etc. I don't think we're quite as sensitive as you make us out to be.

Also, consider the context within which we are considering such a trip: survival of the species long term. Maybe adjusting to the gravitation and day/night cycle of a new planet is absolutely terrible. Choosing that over extinction is still the easiest choice in the universe.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#82

Post by vanattab »

radicaldreamer wrote: post #40
baron816 wrote: post #37

Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…

We could try with a much more doable planet like Mars. We could find out if long term survival is impossible, very difficult, possible but difficult, or doable with the right technologies. It's shocking how little appetite there is for redirecting 50% of the budget which is currently allocated to the military to space exploration. I understand that the military is partly a large welfare program which doesn't compete…

>It's shocking how little appetite there is for redirecting 50% of the budget which is currently allocated to the military to space exploration.

50% for the military? All the figures I can find say it's 16% of federal spending.

Edit: As others have pointed out. OP may have been suggesting we redirect 50% of the military budget to space not that the military budget is 50% of the national.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#83

Post by wyager »

baron816 wrote: post #37

Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…

As they say of NYC, "if you can make it here, you can make it anywhere".

People living in large urban centers are essentially 100% disconnected from any sort of natural day/night light cycles, but they still manage (with, admittedly, some negative health effects). Same deal with gravity; the human body can support people who way 2x the average for their demographic, so I don't think 10% different gravity will matter much.

In the worst case, we could probably do genetic modification or just use exogenous hormones to help adapt to weird sleep cycles.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#84

Post by pc86 »

vanattab wrote: post #82
radicaldreamer wrote: post #40

Earlier quoted context omitted.

We could try with a much more doable planet like Mars. We could find out if long term survival is impossible, very difficult, possible but difficult, or doable with the right technologies. It's shocking how little appetite there is for redirecting 50% of the budget which is currently allocated to the military to space exploration. I understand that the military is partly a large welfare program which doesn't compete…

>It's shocking how little appetite there is for redirecting 50% of the budget which is currently allocated to the military to space exploration. 50% for the military? All the figures I can find say it's 16% of federal spending. Edit: As others have pointed out. OP may have been suggesting we redirect 50% of the military budget to space not that the military budget is 50% of the national.

They're saying cut the military's budget in half and put the rest toward space exploration.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#85

Post by pgwhalen »

vanattab wrote: post #82
radicaldreamer wrote: post #40

Earlier quoted context omitted.

We could try with a much more doable planet like Mars. We could find out if long term survival is impossible, very difficult, possible but difficult, or doable with the right technologies. It's shocking how little appetite there is for redirecting 50% of the budget which is currently allocated to the military to space exploration. I understand that the military is partly a large welfare program which doesn't compete…

>It's shocking how little appetite there is for redirecting 50% of the budget which is currently allocated to the military to space exploration. 50% for the military? All the figures I can find say it's 16% of federal spending. Edit: As others have pointed out. OP may have been suggesting we redirect 50% of the military budget to space not that the military budget is 50% of the national.

I believe he's just saying 50% of what is currently allocated for the military, so by your math, 8% of the federal budget.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#86

Post by pc86 »

kowdermeister wrote: post #72
jcadam wrote: post #49

Earlier quoted context omitted.

Good, the folks on the faster ship can arrive ahead of us 'poor guys' on the first ship and get stuck with all of the hard work of establishing the colony and performing any necessary terraforming before we arrive.

It would still suck to arrive at a supposed to be human free planet just to realize they have a 2000 years of history :) On the other hand, they would probably have beer.

If they don't, I'm going back home.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#87

Post by ceejayoz »

Pigo wrote: post #43
baron816 wrote: post #37

Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…

I'm left wondering these same kind of issues every time there's a Mars habitation post. Having a third the gravity, microscopic dust, and a complete lack of nature (or Internet) seems to be trivial to some people.

> Having a third the gravity

Sounds fun!

> microscopic dust

Found on earth! I change my HVAC filters regularly.

> and a complete lack of nature

There's plenty of nature on Mars. Not much life, but we'll bring that with us. I'd suspect early colonists will have more plant life in their quarters and living areas than your average NYC resident.

> or Internet

I'd fully expect a solution along the lines of Netflix's edge caches for this by the time we're seriously considering building a base. Daily snapshots of Reddit, StackOverflow, major news sites, etc.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#88

Post by vinchuco »

baron816 wrote: post #37

Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…

Weird question. Can we make Earth a spaceship by somehow manipulating the orbit of the moon?

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#89

Post by Tossrock »

gpderetta wrote: post #71
jballanc wrote: post #55

Earlier quoted context omitted.

Even at 50% the speed of light, adding in a fudge factor for acceleration/deceleration, you're still talking about a trip time of 50 yrs. Even if you go all Neon Genesis and send 15 year olds on the journey, they'll be at retirement age by the time they arrive. In other words, you'd almost definitely have to send a generation ship. Which means you'd have to have already figured things like artificial gravity, giving…

Interestingly, while on earth 50 years will have elapsed, because of time dilation on the ship only about 40 years will have elapsed. It will get exponentially closer to 0 elapsed time as the speed approaches c. At 90% c only about 20 years will have elapsed [1]. Equivalently, as the travelers approach c, the distance to the destination will appear shorter. [1] disclaimer: I didn't do the math, i just googled the tab…

The math is actually quite simple to do yourself, your dilation factor is just 1 / sqrt(1-x^2), where x is a percentage of c from 0 to 1. So at 0c, your factor is 1 (obviously), at .5c it's 1.15, and at .9c it's 2.294.

Divide the elapsed time in the stationary reference frame by the dilation factor and you get values that roughly agree with yours.

Re: Four Earth-sized planets detected orbiting the nearest sun-like star

#90

Post by eggpy »

vinchuco wrote: post #88
baron816 wrote: post #37

Ok, let's assume we find a warm, watery planet like Earth's within ~20 light years, and we figure out a way to travel >= 50% the speed of light, making it somewhat reasonable to get there. If the planet's gravity is greater than 10% different from Earth's, or its Day/Night cycle is much different from Earth's, wouldn't it still be a nightmare to live on. Anatomically modern humans have lived on Earth for 200,000 year…

Weird question. Can we make Earth a spaceship by somehow manipulating the orbit of the moon?

We'd have to figure out how to get the earth spinning beyond the escape velocity of the Sun. So, probably not just by manipulating the orbit of the moon.
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