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

nature.com

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

#441

Post by Arizhel »

kristopolous wrote: post #428
tim333 wrote: post #142

Earlier quoted context omitted.

Though that kind of performance is probably not going to come about from improvements to chemical rockets but moving to fusion. There are some promising developments on fusion reactors (see Breakthrough in Nuclear Fusion? - Prof. Dennis Whyte https://www.youtube.com/watch?v=KkpqA8yG9T4 ) Guess something like that with the 100 million C gas doing the propulsion maybe?

There may have to be some clever system where you don't take a lot of fuel with you. Imagine a type of particle accumulator and aggregator - call it cosmic flypaper. If you're going say 100 km/s, things seemingly insignificant and rare you may be able to collect a lot of pretty quickly.

It sounds like you're talking about the Bussard Ramjet. It collects interstellar hydrogen gas for use in fusion engines. The problem is that it's unlikely there's enough hydrogen floating around for it to really work.

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

#442

Post by K0SM0S »

tempestn wrote: post #399
blueprint wrote: post #312

Earlier quoted context omitted.

I said nothing about war..?

There's no other conceivable extinction event that could occur "a couple years out". If you're talking climate change, then I agree that's a major problem, but on the order of at least decades.

This is precisely what we don't know. If you're talking averages, then sure it takes decades to observe a meaningful change. However climate change of the sort we're anticipating now isn't about averages. It's about peaks, it's about records, and possibly major shifts in equilibrium.

Basically what we witness so far and will keep on seeing are spikes in all directions of the spectrums (e.g. record high temps, but also record lows; rain in the Death Valley and droughts in formerly wet areas). More critically, what little we've been able to gather on how fast climate eras shift from one to the next, it appears that whereas in-cycle change happens rather slowly (change within an era, because averages), climate era shifts could happen very quickly (because chain of events). We're talking going from a warm era to a glacial one within a few years, sometimes months even. A high speculation is that some thongs might upset the Gulfstream and you'd observe climate evolve from year to year.

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

#443

Post by maverick_iceman »

blueprint wrote: post #368
Spare_account wrote: post #367

Earlier quoted context omitted.

Elon Musk is working on that. http://www.spacex.com/mars

And you're certain enough that he's going to be able to do it in time and that he's doing it properly enough that you don't have to do anything about it. And you'll continue to go about doing the exact same things. Got it.

Are you a space activist of some sort?

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

#444

Post by acid__ »

Taniwha wrote: post #418

So how come when NASA tells us there are tiny invisible planets light years away we all applaud, but somehow when they point to the evidence of climate change right here right now it's all a big con?

This strikes me as a rather disingenuous question.

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

#445

Post by c-smile »

Therefore it appears as there are plenty of habitable planets out there. Numbers are big enough to conclude that other life is definitely out there somewhere so are the questions:

1. Where are they all?

2. How humanity will react on appearance of one of them? Will we finally stop our fights inside that sandbox and to focus on challenges that we are facing all together?

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

#446

Post by maverick_iceman »

blueprint wrote: post #217
semaphoreP wrote: post #203

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.

Lots of good reasons to establish a space colony, fleeing the earth is not one of them. By this sort of argument you actually discredit the idea of space exploration.

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

#447

Post by scardine »

gydfi wrote: post #400
tajen wrote: post #318

Earlier quoted context omitted.

At that distance, gravity must be really fun. Tides are not only for water, such tides can also change the height of mountains, the balance of high-rise buildings, infer on volleyball rules, make you fart because of changes in atmospheric pressure, or... be leveraged to generate electricity. Those guys have simili-infinite energy at human scale.

Would they? I mean, we can see geological features on our moon, and our tides are orders of magnitude away from being rock-tearing events. I mean, the moon is small, but... how close do these planets approach, anyway?

The moon is not that small, it is 27% of earth's size. Any other satellite in the solar system is way smaller compared to the planet they orbit. I dare to say that earth and moon are twin planets instead of a planet and a satellite.

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

#449

Post by maverick_iceman »

neaden wrote: post #301
blueprint wrote: post #72

Earlier quoted context omitted.

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. :\

Isn't part of the problem that any ship capable of interstellar travel is also capable of being turned into a WMD? I imagine a lot of people would get really nervous if someone for instance parked a bunch of radioactive material in low earth orbit, and even with fusion there would be the fear that someone could turn the ship around.

Jet planes can also be used to destroy skyscrapers. People don't seem to get really nervous about them.

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

#450

Post by mjevans »

vkou wrote: post #288
Someone1234 wrote: post #259

Earlier quoted context omitted.

Particularly in Voyager. They were either running extremely low early in the show or had a virtually infinite supply later in the show. No explanation given. Which is particularly troublesome given the plot of the Equinox episodes. Since on that ship they were harvesting creates to extend their dilithium crystal supply allowing them to travel faster/less efficiently. But even throughout those episodes they never disc…

Voyager spent most of the first season looking for deuterium, so that they could keep the ship moving forward. Presumably, at some point around episode ~15, someone in either engineering, or the writing team realized that it is the third most abundant element in the universe.

It doesn't just have to be common, it has to be worth harvesting.

It could be that it took them this long to locate and get to such a supply, or that they had to repair / construct equipment that normally wouldn't be expected to be used.

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