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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

#461

Post by maverick_iceman »

Arizhel wrote: post #415
blueprint wrote: post #374

Earlier quoted context omitted.

You're familiar with the fact that there is no proper, substantial, accepted model or principle of both gravity and EM that unify them, correct? And we don't knowingly have the ability to build technology that manipulates gravity (trivial interpretations aside). And we also don't know how our actions actually affect the dynamic field that is gravity. Cause the stress-energy tensor says it is dynamic. Or perhaps I'm j…

What exactly are you saying? That once we really figure out gravity, faster-than-light travel will become possible? I've been saying that for years, and I'm no physicist. It's fairly obvious that gravity is not well understood by our physics. All we really know is that it correlates to the presence of mass: lots of mass (like a planet) equals a noticeable amount of gravity. Unlike electromagnetism, where we have the…

General relativity gives a very solid and accurate understanding of gravity.

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

#462

Post by rybosome »

noobermin wrote: post #88
JumpCrisscross wrote: post #34

Earlier quoted context omitted.

> are there...hazards simply due to the proximity of a dim star Tidal locking [1]. Similar to how our moon shines at us ass first all the time, the planets around TRAPIST-1 would be expected to have one face locked to their star. Instead of an equatorial belt bookended with loops of temperate zones, as we have on Earth, we should expect, climatically, an "equatorial" face and a "polar" face separated by a tropic-to-t…

Of course, #askNasa didn't win me a question, but could any astrobiologists comment on this question: Tidal locking means the planets would always have a side facing the star, leading to very different thermodynamics in terms of climate and weather on the planet, not to mention radiation. Doesn't that very much hurt the chances for life on those planets?

I'm not a biologist, but here's a fascinating article on the subject: http://m.nautil.us/blog/forget-earth_likewell-first-find-ali...

TL;DR is that there may exist a band around the planet where the two zones meet that is habitable. I think it's a reasonable supposition that most of the rest of the planet would be uninhabitable.

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

#463

Post by Taniwha »

acid__ wrote: post #444
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.

why? either you think NASA is good at science or you don't, you can't pick and choose depending on whether or not you like the results

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

#464

Post by maverick_iceman »

blueprint wrote: post #330
matwood wrote: post #295

Earlier quoted context omitted.

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.

You're completely missing my point. We've known about climate change for a long time. Since the 60s/70s, no? But nobody has been able to realize what it really is, because scientists do not understand gravity yet. I've been begging people to confirm this for themselves instead of believing what others say about it. If people really knew what global warming was they would have started working on ships decades ago. My…

Scientists understand gravity very well, pick up any book on general relativity.

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

#465

Post by ConceptJunkie »

ccozan wrote: post #427
gydfi wrote: post #400

Earlier quoted context omitted.

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?

So it possible to see Avatar like suspended rocks ? Somewhat orbiting some lagrangian point, which is very close to surface.

The Moon is about 2% of Earth's mass, not 27%.

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

#466

Post by nikdaheratik »

jonshariat wrote: post #177

This news is very interesting but how is this different than any of the recent planet discoveries? Anyone mind explaining the significance of this discovery over the others?

The number (as mentioned) is one huge difference. Not necessarily for purposes of exploration, but as something else to consider for part of the Drake equation. It's also another avenue of detection because it's such a small star, that means we can use different methods than just detecting the "wobble" to figure out whether there are planets around the star.

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

#467

Post by ConceptJunkie »

dekhn wrote: post #283
flexie wrote: post #194

Earlier quoted context omitted.

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

Short answer: almost certainly yes, although i presume this is an improbable event.

It's not that improbable. They've found meteorites on Earth that have been identified as having come from Mars based on their mineral contents.

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

#468

Post by maverick_iceman »

drzaiusapelord wrote: post #291
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. :\

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…

You are assuming that this mass will be launched using today's chemically powered rockets. But using nuclear propelled rockets will bring down the launch costs by orders of magnitude.

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

#469

Post by maverick_iceman »

wallace_f wrote: post #128
kcorbitt wrote: post #47

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.

Is it plausible for anything we'd build to travel .998c and survive the journey?

You can look up Project Daedalus's report online. They considered all these issues in great detail and came up with an affirmative answer.

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

#470

Post by maverick_iceman »

elastic_church wrote: post #169
kcorbitt wrote: post #47

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.

All about funding. NASA, for example, is about 35 years behind schedule by my math, solely from funding. Now whether throwing money at a public agency would have made advancements in lensing, transistor along with propulsion technology happen quicker. Thats a tougher question that leans towards the "unlikely".

Funding is not the only issue. Their planning was also a disaster. The Space Shuttle wasted so much money with very little return. If NASA continued with Project Orion and NERVA a Mars colony would have been well established by now.
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