181–190 of 236 posts
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What does this mean? Surrounded by thousands of dead solar systems? Like nearby (dark) stars?
Maybe a tangentially related question, what happens if you form a system very much like our solar system, but the central body never actually ignites and it just remains a dark ball of hydrogen. Would the system still be called a solar system?
Growing up I absorbed all the space stuff I could find. But it wasn't until recently that I realized that the solar system didn't just form into some static natural state where it largely didn't change until say the sun was finished with it's lifespan. Rather it evolves, changes, planets are habitable, then not, moons are formed and break up, even frozen planets are geologically active and are changing, Saturn's ring…
What's mindblowing is the search for planet 9...once you start to realize that we are surrounded by thousands of dead solar systems (brown dwarfs that very likely were red dwarfs before) in our immediate neighborhood. Imagine what we could accomplish by mining their resources!
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The planet might be ok after us, but still might not be able to birth another potentially space faring civilization, dooming earth life to extinction. Look at how: - no other earth based space faring civilization has evolved before us. - other intelligent species do not seem well equipped to do so, as it's hard to evolve tools without hands / prehensile organs (cetaceans), or when your lifespan is short or you're not…
Considering the industrial revolution had been in full swing for a century before the use of fossil fuels became widespread I think you make a poor argument. Just because we were the first doesn't mean we'll be the last. A billion years is a very very very long time, and there are multiple billions of years in the Earth's future.
I don't understand what you mean about it having been in full swing for a century before that.
Growing up I absorbed all the space stuff I could find. But it wasn't until recently that I realized that the solar system didn't just form into some static natural state where it largely didn't change until say the sun was finished with it's lifespan. Rather it evolves, changes, planets are habitable, then not, moons are formed and break up, even frozen planets are geologically active and are changing, Saturn's ring…
What's mindblowing is the search for planet 9...once you start to realize that we are surrounded by thousands of dead solar systems (brown dwarfs that very likely were red dwarfs before) in our immediate neighborhood. Imagine what we could accomplish by mining their resources!
This is incorrect. Red dwarfs will end their lives as black dwarfs. However, no black dwarfs are currently expected to exist because the universe is not old enough yet. Red dwarfs, in particular, are expected to have lifespan of trillions of years.
Growing up I absorbed all the space stuff I could find. But it wasn't until recently that I realized that the solar system didn't just form into some static natural state where it largely didn't change until say the sun was finished with it's lifespan. Rather it evolves, changes, planets are habitable, then not, moons are formed and break up, even frozen planets are geologically active and are changing, Saturn's ring…
I'm not sure how old you are, but a lot has changed , recently, in our knowledge of Earth, its evolution, the solar system, and astronomy. One of the books I had growing up was a Patrick Moore juvenile book on astronomy, probably Seeing Stars (1970). That had a ... pretty good ... description of the state of knowledge at the time, but it was published only about five years after the 4.5 billion year figure for the ag…
We should NEVER accept a hypothesis as fact because that makes people stop thinking or searching for answers. And there’s no way we can even definitively say something that happened tens of millions of years ago actually happened.
I personally think it was an asteroid too, but I never want to be arrogant enough to think it’s a closed case now. For example, it could have been the switching of the poles causing cosmic radiation to cause mass extinction, similar to why the Neanderthals disappeared and there would be no way for us to know.
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Maybe a tangentially related question, what happens if you form a system very much like our solar system, but the central body never actually ignites and it just remains a dark ball of hydrogen. Would the system still be called a solar system?
That'd be more of a rogue planet with moons.
(But i guess our moon could have moons so it's moons all the way down)
Earlier quoted context omitted.
I'm not sure how old you are, but a lot has changed , recently, in our knowledge of Earth, its evolution, the solar system, and astronomy. One of the books I had growing up was a Patrick Moore juvenile book on astronomy, probably Seeing Stars (1970). That had a ... pretty good ... description of the state of knowledge at the time, but it was published only about five years after the 4.5 billion year figure for the ag…
Very good point. I'm in my 30s and it's even come a long way since I was a kid. We didn't know until recently that there were planets orbiting other stars. We suspected that there might be, but we didn't know. The idea that there could be other "earth-like planets" was a hopeful guess. When the headlines started coming in from Kepler, that was huge. Very exciting and huge.
That is going to be huge news if we find it (I suspect we'll get a lot of other results first though and a ton of new interesting work looking for alternative photosynthetic chemistries).
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But the outer planets have excesses of hydrogen, so round trips could help there? The upside is, of water aka H2O that we need, the 2 H atoms are the lighter component, specifically: 2H = 2 * 1.67 * 10(-24) grams 1O = 1 * 2.65 * 10(-23) grams So hydrogen is 11% of water, and oxygen is 88%; meaning every kg hydrogen can combine with 8kg oxygen to give 9L water. So all the Oxygen already being there (in CO2) is good.
If we were capable of planetary-scale transportation of materials, we wouldn't really need to live on planets anyway - it'd be a rather moot point.
Early stage terraforming need not be too fussed about collateral damage from multiple extinction-events (and the footage I presume would be spectacular).
And it could be again... I wish we would plan ahead and try a solar shield at L1. If we cooled the planet sufficiently, the CO2 would solidify and we could get to work processing it. Venus is far more interesting than the dusty little rock we keep probing. Sure, it may take a millenium, but the sooner we start, the sooner we finish.
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Very good point. I'm in my 30s and it's even come a long way since I was a kid. We didn't know until recently that there were planets orbiting other stars. We suspected that there might be, but we didn't know. The idea that there could be other "earth-like planets" was a hopeful guess. When the headlines started coming in from Kepler, that was huge. Very exciting and huge.
The big news we're looking for from James Webb is the possibility of grabbing evidence of chlorophyll fringes in the IR spectra of other planets. That is going to be huge news if we find it (I suspect we'll get a lot of other results first though and a ton of new interesting work looking for alternative photosynthetic chemistries).
https://www.jwst.nasa.gov/content/forScientists/faqScientist...