General Discussion
Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region ForumsDear Beings in the multiverse, Could you PLEAAAAASE stop using Earth for
dumping off all your undesirables? Whatever we on this small blue marble have done to offend you, we promise to try to fix it, as soon as you tell us what it was.
I can only imagine that it must have been truly heinous, to saddle us with the orange thing, the russian monster, the christofascists, the misogynists, and all their assorted mental and emotional ilk.
This planet might not be much in the vast scheme of things, but it is our home, at least for the moment, and some of us are rather fond of it, however odd that may seem.
Thank you in advance for your prompt and thoughtful consideration of this matter.
Cordially,
Sane Earth Citizens
dweller
(23,562 posts)the island of broken toys
😐
✌🏻
niyad
(112,435 posts)in2herbs
(2,942 posts)sentiment -- from the 70s.
niyad
(112,435 posts)electric_blue68
(14,623 posts)Leith
(7,802 posts)The clue is in the name of the cult.
niyad
(112,435 posts)keithbvadu2
(36,369 posts)D'ya suppose aliens lock their doors when passing by Earth?
niyad
(112,435 posts)Bernardo de La Paz
(48,789 posts)Caption: You fools! It's getting away!
niyad
(112,435 posts)PoindexterOglethorpe
(25,750 posts)but the chances of alien beings being here is essentially zero. Sorry. Think real hard about the enormity of interstellar distances, and consider that something 85% of stars in our galaxy, (and in the rest of the Universe) are Red Dwarfs, which means conditions on planets around Red Dwarfs would be vastly different from conditions around a star like ours, the possibility of alien beings who might be remotely like us is pretty close to zero.
Yeah, this is our only planet and we should be taking a lot better care of it.
Bernardo de La Paz
(48,789 posts)Conceivably, possibly, an advanced civilization may have found a Warp Drive to bust the speed limit of light, but there is large possibility that it can't be busted at all. (See Fermi Paradox link at end)
I am sure that there are dozens of intelligent life forms around the universe and easily could be millions among the trillions of galaxies that contain billions of stars.
Out of 5,000 or so discovered exo-planets, we have found one that seems to have a watery atmosphere and may be in the liquid water zone around its star. For a long time we thought that few stars might have planets.
N = R? · fp · ne · fl · fi · fc · L
where
N = the number of civilizations in our galaxy with which communication might be possible (i.e. which are on our current past light cone)
R? = the average rate of star formation in our Galaxy
fp = the fraction of those stars that have planets
ne = the average number of planets that can potentially support life per star that has planets
fl = the fraction of planets that could support life that actually develop life at some point
fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations)
fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space
L = the length of time for which such civilizations release detectable signals into space[5][6]
As many skeptics have pointed out, the Drake equation can give a very wide range of values, depending on the assumptions,[52] as the values used in portions of the Drake equation are not well established.[27][53][54][55] In particular, the result can be N ≪ 1, meaning we are likely alone in the galaxy, or N ≫ 1, implying there are many civilizations we might contact. One of the few points of wide agreement is that the presence of humanity implies a probability of intelligence arising of greater than zero.[56]
As an example of a low estimate, combining NASA's star formation rates, the rare Earth hypothesis value of fp · ne · fl = 10?5,[57] Mayr's view on intelligence arising, Drake's view of communication, and Shermer's estimate of lifetime:
R? = 1.53 yr?1,[19] fp · ne · fl = 10?5,[33] fi = 10?9,[38] fc = 0.2[Drake, above], and L = 304 years[48]
gives:
N = 1.5 × 10?5 × 10?9 × 0.2 × 304 = 9.1 × 10?13
i.e., suggesting that we are probably alone in this galaxy, and possibly in the observable universe.
On the other hand, with larger values for each of the parameters above, values of N can be derived that are greater than 1. The following higher values that have been proposed for each of the parameters:
R? = 1.53 yr?1,[19] fp = 1,[22] ne = 0.2,[58][59] fl = 0.13,[60] fi = 1,[40] fc = 0.2[Drake, above], and L = 109 years[49]
Use of these parameters gives:
N = 3 × 1 × 0.2 × 0.13 × 1 × 0.2 × 109 = 15,600,000
Monte Carlo simulations of estimates of the Drake equation factors based on a stellar and planetary model of the Milky Way have resulted in the number of civilizations varying by a factor of 100.[61]
If we use the last set of parameters and then instead of applying a billion years, apply only a thousand years, you still get about 16 civilizations, currently, in only the Milky Way.
But of course we must also consider the Fermi Paradox.
PoindexterOglethorpe
(25,750 posts)First off is that most galaxies are already so far away we could never possible travel to them. Or anyone from those galaxies would ever get here.
My son is working on a PhD in astronomy and doing exo-planet research. It turns out that pretty much every star we look at has planets. However, so far we haven't found one that is remotely earth-like. They're mostly gas giants close to their suns. Hot Jupiters. Any life that might develop there would be so vastly different from what we have here that we might not even recognize it as life. Plus, a significant percentage of stars in our galaxy are simply too close to the center of it for planetary conditions remotely like ours to exist. Stars very close together, lots and lots of deadly radiation.
The Drake Equation ignores the fact that conditions on this planet are, so far as we can tell, unique, possibly unduplicated anywhere in our galaxy. Our large moon is a huge factor in life developing here. It gives us the tides that helped life evolve here.
Again, some 85% of stars are red dwarfs. So conditions on an otherwise earth-like planet with a red dwarf sun, would be very different from what we had here. It also took several billion years from the time life first showed up here, to multi-cellular life to evolve, and then eventually all the vast forms of life we now have on the planet.
But okay, on the fringes of the galaxy, away from the worst of the deadly radiation, there might well be any number of stars like ours, and some of those may well have a truly earth-like planet or two. However, if they are on the opposite side of our galaxy, so about 100,000 light years away. Again, an insurmountable distance.
Even if there is a technological civilization within 50 light years, we wouldn't be able to tune in to their radio or TV signals. Heck, you can't even watch TV on the moon. The signals simply don't go that far, let alone many light years.
Keep in mind that the SETI project (Search for Extra-Terrestrial Intelligence) does not attempt to listen to ordinary broadcast bands, but to something that we ourselves are definitely not broadcasting on.
Bernardo de La Paz
(48,789 posts)Generic Brad
(14,270 posts)I shudder at the thought.