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Seven earth-sized planets discovered circling a star 39 light years from Earth

nature.com

291–300 of 754 posts

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#291

Earlier quoted context omitted.

That actually sounds... more plausible than I would have expected. Like, doable with technology I can imagine being within reach in the next 50 years even if we don't achieve any currently-unforseen breakthroughs.

Which begs the question, why haven't we at least even tried to have done anything like this already? Do we really need to repeatedly spend comparable amounts of money on yet another dramatic TV special about humans traveling to Mars, as narrated by a favored celebrity? We really are running out of time. And it almost seems like it's pre-determined to happen. :\

The launch cost of launching the mass of the pyramids of gaza into orbit would bankrupt the richest economies. No your hypothetical engine won't be 100% efficient. This is completely unfeasible.

Low mass spacecraft are our only real options. A nano-sized solar sail craft powered by the sun or lasers from Earth can hit up to 20% lightspeed theoretically and its launch costs would be affordable, if not relatively cheap. We could have a spacecraft at Alpha Centauri in merely 20 years. Or simply launch them by the dozens or hundreds to various locations. Stephen Hawking has proposed this system in the past and we've had trial launches of solar sails via the planetary society and others. Its a solid and most likely doable concept at scale. Yes, your kids or grandkids will hear the results, but not you. Is that such a problem, especially when the alternatives are never launching a probe to those systems?

To be fair, the proposed Centauri mission would be within a person's lifetime. 20 years to get there then another 4 and half to get the data. So if we launch when you're in your 40s or even 50s, you'll still see the data.

We can even use this concept on heavier ships in the solar system to get to Mars quickly. How quickly? Three days quickly for a 100kg craft. This is a bit more pie-in-the-sky of course:

http://www.sciencealert.com/nasa-scientists-are-investigatin...

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#294

Earlier quoted context omitted.

But what if we are the first and no filter exists at all?

That's almost equally depressing. "Really, we're the best the universe has to offer?"

I expect the first species that is physically capable of colonising the stars will /only just/ be capable of it.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#295

Earlier quoted context omitted.

That actually sounds... more plausible than I would have expected. Like, doable with technology I can imagine being within reach in the next 50 years even if we don't achieve any currently-unforseen breakthroughs.

Which begs the question, why haven't we at least even tried to have done anything like this already? Do we really need to repeatedly spend comparable amounts of money on yet another dramatic TV special about humans traveling to Mars, as narrated by a favored celebrity? We really are running out of time. And it almost seems like it's pre-determined to happen. :\

NASA is not standing still. Europa just went to the next stage for exploration.

http://www.jpl.nasa.gov/news/news.php?feature=6755

It just takes a lot of time to plan and build ships for space travel.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#296

Earlier quoted context omitted.

A Russian billionaire is trying: https://breakthroughinitiatives.org/Initiative/3

I'm talking about establishing a self-sufficient colony somewhere other than Earth. We have a major crisis on our hands. And few are even willing to consider let alone research and confirm that we're talking about an extinction event much sooner than we thought, maybe on the order of just a couple years out. Problem is, we don't know. Bigger problem is, we're not doing anything about it.

If its affordable to send people to an off world colony then its affordable to bomb it when war on Earth breaks out. Fleeing isn't going to help in a wartime situation and the idea it will not be targeted by world powers is a little naive.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#297
post #134

Earlier quoted context omitted.

There has been and continues to be cross-contamination between Venus, Earth, and Mars, so it seems likely that planets much closer together, and passing each other more frequently would have more 'communication' of materials.

Continues to be...? Outside of human action, what's the vector?

https://en.wikipedia.org/wiki/Martian_meteorite

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#298

Earlier quoted context omitted.

> about...2,000 Saturn V rockets Or about 670 BFRs [1]. It would take 6 cycles of tripling size and/or performance to get a single system with enough thrust to meet your 7/42 year schedule. The Saturn V first flew in 1967 [1]; SpaceX plans to launch its Interplanetary Transport System (ITS) in 2022 or 2024 [2]. That's an expected 60 years to triple performance. [1] http://waitbutwhy.com/2016/09/spacexs-big-fking-rock…

To put that 60 years into perspective: It was 66 years between the first powered airplane flight and landing people on the moon.

These kinds of realizations make me sad that life is so relatively short.

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#299
post #194
post #131

Earlier quoted context omitted.

Very likely, since this happens between Mars and Earth: https://en.wikipedia.org/wiki/Martian_meteorite

Fascinating! Would vira or bacteria beable to survive travelling from Earth to Mars in or on a rock or vice versa?

Tardigrades do survive in space: https://en.wikipedia.org/wiki/Tardigrade

Re: Seven earth-sized planets discovered circling a star 39 light years from Earth

#300

Earlier quoted context omitted.

That's essentially what blueprint said. You didn't have any trouble figuring out what blueprint was saying, right?

What's wrong with begs the question? It's a regular part of my vocabulary and I'm a southern American.

"Begs the question" refers to a logical fallacy[1], though in modern language usually it's conflated with "invites the question" (which is what people generally mean when they say "begs the question" outside of a comment thread on Reddit).

[1]: https://en.wikipedia.org/wiki/Begging_the_question

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