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Are we alone in the Galaxy?

#21

#19
"Why no aliens have ever stopped here to say hi?"

  • The nearest star Proxima Centauri is 4 light years away.
#19 "Why no aliens have ever stopped here to say hi?" * The nearest star Proxima Centauri is 4 light years away.
#22

https://youtu.be/XJwDlLiQpS4?si=Ayslt233dj1Lh6hM

https://science.nasa.gov/astrophysics/programs/habitable-worlds-observatory/

https://youtu.be/_1mpHBAXh1c?si=xdD40wz9PeIUInJF

https://science.nasa.gov/mission/webb/science-overview/science-explainers/spectroscopy-101-introduction/

https://www.skyatnightmagazine.com/news/kepler-discovers-earth-2-0

https://youtu.be/XJwDlLiQpS4?si=Ayslt233dj1Lh6hM https://science.nasa.gov/astrophysics/programs/habitable-worlds-observatory/ https://youtu.be/_1mpHBAXh1c?si=xdD40wz9PeIUInJF https://science.nasa.gov/mission/webb/science-overview/science-explainers/spectroscopy-101-introduction/ https://www.skyatnightmagazine.com/news/kepler-discovers-earth-2-0
#24

Even a strong, e.g. commercial broadcast, non-directional radio signal's strength deteriorates badly after a few dozen light years due to the inverse square law. In order for us to pick up a signal it would require an extremely powerful transmitter to be pointed at us, at the right time in our technological evolution for us to receive the message.

The odds of Earth being targeted at random and in time (for reception) are incredibly low, even if there are a 100 human-equivalent civilisations scattered across the galaxy at this moment.

Even a strong, e.g. commercial broadcast, non-directional radio signal's strength deteriorates badly after a few dozen light years due to the inverse square law. In order for us to pick up a signal it would require an extremely powerful transmitter to be pointed at us, at the right time in our technological evolution for us to receive the message. The odds of Earth being targeted at random and in time (for reception) are incredibly low, even if there are a 100 human-equivalent civilisations scattered across the galaxy at this moment.
#25

We are not alone , God is with us.xxx

We are not alone , God is with us.xxx
#26

@tpr said in #8:

It is possible, but unlikely.
Earth is close enough to the Sun to receive enough energy, but not too close so as not to overheat like Mercurius or Venus.
Earth has a Moon to sweep away incoming asteroids.
Earth has a magnetic field to keep us safe from cosmic radiation.
Earth has an ozone layer to keep us safe from ultraviolet radiation.
Earth has water.

You are "only" talking about the solar system though. The question was about the galaxy. The galaxy is big. You just won't believe how vastly, hugely, mind-bogglingly big it is.

@tpr said in #8: > It is possible, but unlikely. > Earth is close enough to the Sun to receive enough energy, but not too close so as not to overheat like Mercurius or Venus. > Earth has a Moon to sweep away incoming asteroids. > Earth has a magnetic field to keep us safe from cosmic radiation. > Earth has an ozone layer to keep us safe from ultraviolet radiation. > Earth has water. You are "only" talking about the solar system though. The question was about the galaxy. The galaxy is big. You just won't believe how vastly, hugely, mind-bogglingly big it is.
#27

@CSKA_Moscou said in #20:

There is a paradox. If life flourishes in the Universe, why we don't see any, or communicate with any, even sending radio signals? Why no aliens have ever stopped here to say hi? Or am I missing something?

They may be more evolved than us and, in that case, deliberately choose not to interfere with our planet.

They may be less evolved or as evolved as us and lack the technology for space travel and light speed.

They may be extinct, and we may not have received or deciphered their messages.

They may not be the same life forms as those on Earth, or they may be in the early stages of evolution (bacteria, fungi).

Another solution rests on the observation that the Universe is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. So even if there are plenty of alien civilisations out there, they might be so far away from us that the chances of them bumping into us by sheer luck are astronomically low.

@CSKA_Moscou said in #20: > There is a paradox. If life flourishes in the Universe, why we don't see any, or communicate with any, even sending radio signals? Why no aliens have ever stopped here to say hi? Or am I missing something? > > They may be more evolved than us and, in that case, deliberately choose not to interfere with our planet. > > They may be less evolved or as evolved as us and lack the technology for space travel and light speed. > > They may be extinct, and we may not have received or deciphered their messages. > > They may not be the same life forms as those on Earth, or they may be in the early stages of evolution (bacteria, fungi). Another solution rests on the observation that the Universe is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. So even if there are plenty of alien civilisations out there, they might be so far away from us that the chances of them bumping into us by sheer luck are astronomically low.
#28

@SimonBirch said in #25:

We are not alone , God is with us.xxx

God doesn't exist.

@SimonBirch said in #25: > We are not alone , God is with us.xxx God doesn't exist.
#29

Over 100 billion stars in the Galaxy, over 100 billion planets, we are almost becoming interplanetary.

The fermi paradox says: If life forms naturally in the universe, then why, with so many planets and stars, aren't there species flying around, saying "hi" to us, being interstellar and multiplying themselves?

There are 3 answers. Each one of them is cientifically possible, and intrigues me right now:

1 - Life is extremely unlikely and rare. So we are probably the most intelligent life-form in the entire Galaxy of 100 billion stars.

Arguments:

There are in average 1-2 planets per star, and our solar system has 9 (considering the Hearted Pluto, which will always be a planet!), Jupiter protects us from meteorites, our moon does that aswell. This is extremely rare, to have such a big planet shielding us, a moon, and at the same time, our planet has a medium size, which allows our gravity to be average, and allow life-formation.

Only 6% of the stars are similar to the sun. Another luck.

Abundance of water. Not all planets have that.

Magnetism.

The right distance from the Sun...

Over 100 billion stars in the Galaxy, over 100 billion planets, we are almost becoming interplanetary. The fermi paradox says: If life forms naturally in the universe, then why, with so many planets and stars, aren't there species flying around, saying "hi" to us, being interstellar and multiplying themselves? There are 3 answers. Each one of them is cientifically possible, and intrigues me right now: 1 - Life is extremely unlikely and rare. So we are probably the most intelligent life-form in the entire Galaxy of 100 billion stars. Arguments: There are in average 1-2 planets per star, and our solar system has 9 (considering the Hearted Pluto, which will always be a planet!), Jupiter protects us from meteorites, our moon does that aswell. This is extremely rare, to have such a big planet shielding us, a moon, and at the same time, our planet has a medium size, which allows our gravity to be average, and allow life-formation. Only 6% of the stars are similar to the sun. Another luck. Abundance of water. Not all planets have that. Magnetism. The right distance from the Sun...
#30

There are 3 answers. Each one of them is cientifically possible, and intrigues me right now:

2 - Life is not rare, but the events that trigger self-destruction of an intelligent specie are common, so we are probably one of the smartest living beings on the Galaxy, because smarter ones erradicated themselves, that's why there are nobody visiting us.

This is probably the dominant scientific argument, nowadays. Very negative, it considers things like AI, nuclear weapons, global warming, environmental depletion, loss of biodiversity, as examples that we, as an intelligent specie, by conflicting with each other, we can trigger our own extinction, and we become more and more powerful, more and more capable, this knowledge can lead us to our own extinction, so we would very likely, in that case, end up like all the other evolving species in the cosmos: eliminating ourselves.

I've always believed in love, and that we can reverse damages and create life. The risks are greater, but I think we can surpass them. I don't believe in this explanation, that is the most accepted scientific view, to be the actual truth for the species, and the answer for the Fermi Paradox. I believe some species can trigger self-destruction when love is not present.

I'll go for the final possibility that I'll raise here in this topic. Number 3:

There are 3 answers. Each one of them is cientifically possible, and intrigues me right now: 2 - Life is not rare, but the events that trigger self-destruction of an intelligent specie are common, so we are probably one of the smartest living beings on the Galaxy, because smarter ones erradicated themselves, that's why there are nobody visiting us. This is probably the dominant scientific argument, nowadays. Very negative, it considers things like AI, nuclear weapons, global warming, environmental depletion, loss of biodiversity, as examples that we, as an intelligent specie, by conflicting with each other, we can trigger our own extinction, and we become more and more powerful, more and more capable, this knowledge can lead us to our own extinction, so we would very likely, in that case, end up like all the other evolving species in the cosmos: eliminating ourselves. I've always believed in love, and that we can reverse damages and create life. The risks are greater, but I think we can surpass them. I don't believe in this explanation, that is the most accepted scientific view, to be the actual truth for the species, and the answer for the Fermi Paradox. I believe some species can trigger self-destruction when love is not present. I'll go for the final possibility that I'll raise here in this topic. Number 3:

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