Do You Believe Aliens Have Visited Earth? (1 Viewer)

[Parrothead]

Has anyone made an immigration joke? I always think those are pretty funny political satire.

build a big wall around the atmosphere to keep them out

 

[chauncey]

http://www.astrobio.net/topic/solar-system/meteoritescomets-and-asteroids/scientist-suggests-comet-and-meteorite-impacts-made-life-on-earth-possible/

Scientist Suggests Comet and Meteorite Impacts Made Life on Earth Possible

By Astrobio - Nov 6, 2013

It has baffled humans for millennia: how did life begin on planet Earth? Now, new research from a Texas Tech University paleontologist suggests it may have rained from the skies and started in the bowels of hell.

Sankar Chatterjee, Horn Professor of Geosciences and curator of paleontology at the Museum of Texas Tech University believes he has found the answer by connecting theories on chemical evolution with evidence related to our planets early geology.

This is bigger than finding any dinosaur, Chatterjee said. This is what weve all searched for the Holy Grail of science.

Thanks to regular and heavy comet and meteorite bombardment of Earths surface during its formative years 4 billion years ago, the large craters left behind not only contained water and the basic chemical building blocks for life, but also became the perfect crucible to concentrate and cook these chemicals to create the first simple organisms.

He presented his findings Oct. 30 during the 125th Anniversary Annual Meeting of the Geological Society of America in Denver.

As well as discovering how ancient animals flew, Chatterjee discovered the Shiva Meteorite Crater which was created by a 25-mile-wide meteorite that struck off the coast of India. This research concluded this giant meteorite wreaked havoc simultaneously with the Chicxulub meteorite strike near Mexico, finishing the dinosaurs 65 million years ago.

Ironically, Chatterjees latest research suggests meteorites can be givers of life as well as takers. He said that meteor and comet strikes likely brought the ingredients and created the right conditions for life on our planet. By studying three sites containing the worlds oldest fossils, he believes he knows how the first single-celled organisms formed in hydrothermal crater basins.

When the Earth formed some 4.5 billion years ago, it was a sterile planet inhospitable to living organisms, Chatterjee said. It was a seething cauldron of erupting volcanoes, raining meteors and hot, noxious gasses. One billion years later, it was a placid, watery planet teeming with microbial life the ancestors to all living things.

Recipe for Living

For may years, the debate on the origins of life centered on the chemical evolution of living cells from organic molecules by natural processes. Chatterjee said life began in four steps of increasing complexity cosmic, geological, chemical and biological.

In the cosmic stage, a still-forming Earth and our solar system took a daily pounding from rocky asteroids and icy comets between 4.1 to 3.8 billion years ago. Plate tectonics, wind and water have hidden evidence of this early onslaught on our planet, but ancient craters on the surfaces of Mars, Venus, Mercury and our moon show just how heavy the meteorite showers once were.

Larger meteorites that created impact basins of about 350 miles in diameter inadvertently became the perfect crucibles, he said. These meteorites also punched through the Earths crust, creating volcanically driven geothermal vents. Also, they brought the basic building blocks of life that could be concentrated and polymerized in the crater basins.

After studying the environments of the oldest fossil-containing rocks on Earth in Greenland, Australia and South Africa, Chatterjee said these could be remnants of ancient craters and may be the very spots where life began in deep, dark and hot environments.

Because of Earths perfect proximity to the Sun, the comets that crashed here melted into water and filled these basins with water and more ingredients. This gave rise to the geological stage. As these basins filled, geothermal venting heated the water and created convection, causing the water to move constantly and create a thick primordial soup.

The geological stage provides special dark, hot, and isolated environments of the crater basins with the hydrothermal vent systems that served as incubators for life, he said. Segregation and concentration of organic molecules by convective currents took place here, something like the kinds we find on the ocean floor, but still very different. It was a bizarre and isolated world that would seem like a vision of hell with the foul smells of hydrogen sulfide, methane, nitric oxide and steam that provided life-sustaining energy.

Then began the chemical stage, Chatterjee said. The heat churning the water inside the craters mixed chemicals together and caused simple compounds to grow into larger, more complex ones.

Protecting Important Information

Most likely, pores and crevices on the crater basins acted as scaffolds for concentrations of simple RNA and protein molecules, he said. Unlike a popular theory that believes RNA came first and proteins followed, Chatterjee believes RNA and proteins emerged simultaneously and were encapsulated and protected from the environment.

The dual origin of the RNA/protein world is more plausible in the vent environments than the popular RNA world, he said. RNA molecules are very unstable. In vent environments, they would decompose quickly. Some catalysts, such as simple proteins, were necessary for primitive RNA to replicate and metabolize. On the other hand, amino acids, from which proteins are made, are easier to make than RNA components.

The question remains how loose RNA and protein material floating in this soup protected itself in a membrane. Chatterjee believes University of California professor David Deamers hypothesis that membranous material existed in the primordial soup. Deamer isolated fatty acid vesicles from the Murchison meteorite that fell in 1969 in Australia. The cosmic fatty bubbles extracted from the meteorite mimic cell membranes.

Meteorites brought this fatty lipid material to early Earth, Chatterjee said. This fatty lipid material floated on top of the water surface of crater basins but moved to the bottom by convection currents. At some point in this process during the course of millions of years, this fatty membrane could have encapsulated simple RNA and proteins together like a soap bubble. The RNA and protein molecules begin interacting and communicating. Eventually RNA gave way to DNA a much more stable compound and with the development of the genetic code, the first cells divided.

The final stage the biological stage represents the origin of replicating cells as they began to store, process and transmit genetic information to their daughter cells, Chatterjee said. Infinite combinations took place, and countless numbers must have failed to function before the secret of replication was broken and the proper selection occurred.

These self-sustaining first cells were capable of Darwinian evolution, he said. The emergence of the first cells on the early Earth was the culmination of a long history of prior chemical, geological and cosmic processes.

Chatterjee also believes that modern RNA-viruses and protein-rich prions that cause deadly diseases probably represent the evolutionary legacy of primitive RNA and protein molecules. They may be the oldest cellular particles that predated the first cellular life. Once cellular life evolved, RNA-viruses and prions became redundant, but survived as parasites on the living cells.

The problem with theories on the origins of life is that they dont propose any experiments that lead to the emergence of cells, Chatterjee said. However, he suggested an experiment to recreate the ancient prebiotic world and support or refute his theory.

If future experiments with membrane-bound RNA viruses and prions result in the creation of a synthetic protocell, it may reflect the plausible pathways for the emergence of life on early Earth, he said.

Pics or it didn't happen

 

[Jayrok]

I'm surprised at the poll results. I thought we had more Christians on this board. (God is not from earth. Jesus is God. How is Jesus not an alien?)

Hey, you can't prove that, Rusty.

 

[FUBAR]

If you believe in God, why couldn't God have created life on other planets too?

There may be many Gods who each created a planet for their junior high science fair project.

Ours got an A, others failed.

I'm surprised at the poll results. I thought we had more Christians on this board. (God is not from earth. Jesus is God. How is Jesus not an alien?)

Pretty sure I burst their bubbles over the years and set a lot of them straight.

homophobe

 

[Cliff Clavin]

If you believe in God, why couldn't God have created life on other planets too?

There may be many Gods who each created a planet for their junior high science fair project.

Ours got an A, others failed.

That is some easy grading. Earth should get no more than a D-.

 

[FUBAR]

If you believe in God, why couldn't God have created life on other planets too?

There may be many Gods who each created a planet for their junior high science fair project.

Ours got an A, others failed.

That is some easy grading. Earth should get no more than a D-.

He got bonus points for hiding bones which would confuse us, give us power, and cause war.

the instructor graded on a curve.

 

[Zow]

Oof, Jayrod.

Considering anyone's answer is based on preconceived ideas about the origin of the universe, do my comments surprise you?I think God gave us life. Without God there is no life. Science has yet to prove or even discover anything that says otherwise.

Are you a creationist?

Not in the literal 6000 years sense, but in the sense that I believe God, in some form or fashion created the universe and everything in it. I think creationist has come to mean someone who rejects the ideas of evolution and an old earth. I reject neither of those. But I have yet to see anything in abiogenesis research that has convinced me that life came from non-life by random chance.

I don't want to get into a religious debate and absolutely respect your beliefs but having said that, I never understood the notion that because we haven't found the scientific answer to "how was the universe created" it must be God. Seems like a cop-out. Who created "God"?

He's referencing the Prime-Mover Theory. That's the idea that there, logically, must be some initial creator. Theologians conclude that prime mover is God, since nobody created him.

 

[CowboysFromHell]

Oof, Jayrod.

Considering anyone's answer is based on preconceived ideas about the origin of the universe, do my comments surprise you?I think God gave us life. Without God there is no life. Science has yet to prove or even discover anything that says otherwise.

Are you a creationist?

Not in the literal 6000 years sense, but in the sense that I believe God, in some form or fashion created the universe and everything in it. I think creationist has come to mean someone who rejects the ideas of evolution and an old earth. I reject neither of those. But I have yet to see anything in abiogenesis research that has convinced me that life came from non-life by random chance.

I don't want to get into a religious debate and absolutely respect your beliefs but having said that, I never understood the notion that because we haven't found the scientific answer to "how was the universe created" it must be God. Seems like a cop-out. Who created "God"?

He's referencing the Prime-Mover Theory. That's the idea that there, logically, must be some initial creator. Theologians conclude that prime mover is God, since nobody created him.

"I don't know, so therefore God did it." That's fine, but he should be careful when his very next sentence uses the word "proof", since of course there is no proof of his, or any other, gods. I also have a problem with the assertion that any of this is "random chance."

 

[Apple Jack]

I would say 99.9% no if not for the Pyramids. Because of the Pyramids, I'll go 96.341% no. Their is definitely a lot of different life forms throughout the universe, some that we would consider intelligent, and some probably involving dimensions imperceptible to us.

Ancient Egypt has always fascinated me when talking about this topic. I'm not 100% believing that aliens built the pyramids. But there are too many stories told of beings from the sky. Like MT noted, Jesus himself came from the heavens. With so many tales of beings from the sky, it makes me think that someone/something has landed here from another planet at some point in time.

(As far as I know I'm not bat#### crazy)

The pyramids were able to be built well within the technology available at the time. They aren't the Burj Khalifa.

Not to mention Easter Island, Stonehenge and the Coney Island Cyclone.

 

[BroadwayG]

We haven't done anything noteworthy to be visited.

Have you seen the yoga pants thread?

 

[Tusken Raider]

Aliens have already assimilated into professional sports:

Proof

 

[B-Deep]

If you believe in God, why couldn't God have created life on other planets too?

he certainly could have

he also could have revealed himself to the ancient Aztecs as 15 different dieties whose names i cannot pronounce, but most christian mythology does not allow for that

certainly alien life does not eliminate god, but if WE are created in his image and they are different, are we their superiors by divine right? Do they have the original sin? Did jesus die for their sins? did another jesus come down and take their form?

it does raise a lot of questions, and I am fairly certain some religious groups would reject aliens as evil demons out of hand. But then some non religious groups would reject them as well....so take it for what it is worth

 

[B-Deep]

A PERSONAL NOTE TO Giorgio Tsoukalos, PLEASE NO ONE ELSE READ, thx

Spoiler

Girogio if you come in here don't believe a word of what i say. I am arguing to argue, of course I believe there were aliens among us, and we mistook them for divine beings. I still love you you fuzzy-headed *******. How about lunch on Sunday? you choose the place.

 

[Keith R]

Call me skeptical but I will not believe aliens have or are visiting Earth unless I personally observe it happen.

 

[KarmaPolice]

No, and I really don't believe alien life exists elsewhere either.

If there's not then this is the stupidest universe ever.

No doubt

 

[shadyridr]

No, and I really don't believe alien life exists elsewhere either.

If there's not then this is the stupidest universe ever.

No doubt

huge waste of space

 

[Fennis]

Spoiler

It's a cookbook!

 

[cstu]

No, and I really don't believe alien life exists elsewhere either.

If there's not then this is the stupidest universe ever.

No doubt

huge waste of space

Seems part of his lighting plan:[He also made] the stars. God placed them in the heavenly sky to shine on the earth, to rule by day and by night, and to divide between the light and the darkness. God saw that it was good.

 

[Amused to Death]

Aliens created Earth to be a computer designed to calculate the Ultimate Question. Of course we all know the answer to the Ultimate Question is 42.

 

[Yenrub]

We (humans) have visited other planets correct?

 

[3C's]

No, but I believe they've visited Uranus.

 

[Ignoramus]

We (humans) have visited other planets correct?

Thanks for clarifying! For a second there I thought you meant we, as in you and I.

 

[TheIronSheik]

We (humans) have visited other planets correct?

Not in person.

 

[TheIronSheik]

We (humans) have visited other planets correct?

Thanks for clarifying! For a second there I thought you meant we, as in you and I.

Wait. So you guys didn't?

 

[Amused to Death]

No, but I believe they've visited Uranus.

Professor Hubert Farnsworth: I'm sorry, Fry, but astronomers renamed Uranus in 2620 to end that stupid joke once and for all.

Fry: Oh. What's it called now?

Professor Hubert Farnsworth: Urrectum.

 

[MikeIke]

We (humans) have visited other planets correct?

Thanks for clarifying! For a second there I thought you meant we, as in you and I.

Wait. So you guys didn't?

Shhhhh! They weren't invited for a reason!

 

[Hooper31]

Intelligent life? No. Life? Yes.

Assuming you define alien as any non earth life form. Bacteria, simple cell organisms, etc. Intellegent or complicated life who knows.

This poll needs a "Smoo" choice.

Pretty obvious Smoo has visited planet earth.

Based on this important new information I would like to change my vote.

 

[CowboysFromHell]

If you believe in God, why couldn't God have created life on other planets too?

he certainly could have

he also could have revealed himself to the ancient Aztecs as 15 different dieties whose names i cannot pronounce, but most christian mythology does not allow for that

certainly alien life does not eliminate god, but if WE are created in his image and they are different, are we their superiors by divine right? Do they have the original sin? Did jesus die for their sins? did another jesus come down and take their form?

it does raise a lot of questions, and I am fairly certain some religious groups would reject aliens as evil demons out of hand. But then some non religious groups would reject them as well....so take it for what it is worth

This is a re-post from a while back in another thread, but relevant here, and still funny:

Creationist Ken Ham Says Aliens Will Go To Hell So Let's Stop Looking For Them

 

[Mr. Know-It-All]

Exist, but have not visited...

Earth is a grain of sand on the beach in the Universe.

This.There are billions of stars in our galaxy. There are billions of galaxies in our universe. It's even possible that there are billions of universes. We are not all that special.

Well, isn't your glass half empty.

 

[cstu]

For comparison to the bolded, Mars has a ESI of 0.64.

http://www.sci-news.com/astronomy/science-kepler-438b-most-earth-like-exoplanet-02387.html

Kepler-438b has an Earth Similarity Index of 0.88. Prior to its discovery, the two most Earth-like exoplanets known were Gliese 667Cc and Kepler-296e.

“With each new discovery of these small, possibly rocky worlds, our confidence strengthens in the determination of the true frequency of planets like Earth,” said team member Dr Doug Caldwell of NASA’s Ames Research Center at Moffett Field, California, who is a co-author of the paper accepted for publication in the Astrophysical Journal (arXiv.org preprint).

“The day is on the horizon when we’ll know how common temperate, rocky planets like Earth are.”

“This announcement is important because it shows that we are finding many planets in the habitable zone around other stars,” added Prof Lisa Kaltenegger of Cornell University and the Institute for Pale Blue Dots, who was not involved in the discovery.

“Now that we are probing the entire habitable zone around cool stars, we are starting to see the fascinating diversity of such potential Earths.”

According to the astronomers, Kepler-438b is 12 percent bigger than Earth and orbits its parent star, Kepler-438, once every 35.2 days.

The star, also known as KOI-3284, is a red dwarf located in the direction of the constellation Lyra, about 470 light-years away. It is smaller and cooler than our Sun.

To be in the habitable zone, an exoplanet must receive about as much sunlight as Earth. Too much, and any water would boil away as steam. Too little, and water will freeze solid.

Kepler-438b receives about 40 percent more light than Earth. In comparison, Venus gets twice as much solar radiation as our planet.

As a result, Dr Torres and his colleagues calculate it has a 70 percent likelihood of being in the habitable zone of its star. It has also a 70 percent chance of being rocky.

“Each result from the planet-hunting Kepler mission’s treasure trove of data takes us another step closer to answering the question of whether we are alone in the Universe,” said Dr John Grunsfeld of NASA’s Science Mission Directorate.

 

[Insein]

Cornell University and the Institute for Pale Blue Dots

Pale Blue? Is that like dry humping?

 

[ghostguy123]

Call me skeptical but I will not believe aliens have or are visiting Earth unless I personally observe it happen.

you must be skeptical about a whole heck of a lotta things

 

[Insein]

Call me skeptical but I will not believe aliens have or are visiting Earth unless I personally observe it happen.

you must be skeptical about a whole heck of a lotta things

I've never seen a lion except on TV. As far as I know it's just a made up creature.

 

[msommer]

Call me skeptical but I will not believe aliens have or are visiting Earth unless I personally observe it happen.

you must be skeptical about a whole heck of a lotta things

I've never seen a lion except on TV. As far as I know it's just a made up creature.

Where's you nearest Zoo?

 

[CowboysFromHell]

Call me skeptical but I will not believe aliens have or are visiting Earth unless I personally observe it happen.

you must be skeptical about a whole heck of a lotta things

I've never seen a lion except on TV. As far as I know it's just a made up creature.

Where's you nearest Zoo?

What are these things called "zoos" you speak of?

 

[Rohn Jambo]

Call me skeptical but I will not believe aliens have or are visiting Earth unless I personally observe it happen.

you must be skeptical about a whole heck of a lotta things

I've never seen a lion except on TV. As far as I know it's just a made up creature.

Where's you nearest Zoo?

What are these things called "zoos" you speak of?

You should come out of your alien spaceship once in a while.

 

[joffer]

http://www.sciencedaily.com/releases/2015/01/150115163529.htm

study by astrophysicists at the University of Toronto suggests that exoplanets -- planets outside our solar system -- are more likely to have liquid water and be more habitable than we thought.

"Planets with potential oceans could have a climate that is much more similar to Earth's than previously expected," said Jérémy Leconte, a postdoctoral fellow at the Canadian Institute for Theoretical Astrophysics (CITA) at the University of Toronto, and lead author of a study published today in Science Express.

Scientists have thought that exoplanets behave in a manner contrary to that of Earth -- that is they always show their same side to their star. If so, exoplanets would rotate in sync with their star so that there is always one hemisphere facing it while the other hemisphere is in perpetual cold darkness.

Leconte's study suggests, however, that as exoplanets rotate around their stars, they spin at such a speed as to exhibit a day-night cycle similar to Earth.

"If we are correct, there is no permanent, cold night side on exoplanets causing water to remain trapped in a gigantic ice sheet. Whether this new understanding of exoplanets' climate increases the ability of these planets to develop life remains an open question."

Leconte and his team reached their conclusions via a three-dimensional climate model they developed to predict the effect of a given planet's atmosphere on the speed of its rotation, which results in changes to its climate," said Leconte. "Atmosphere is a key factor affecting a planet's spin, the impact of which can be of enough significance to overcome synchronous rotation and put a planet in a day-night cycle."

Though astronomers are still awaiting observational evidence, theoretical arguments suggest that many exoplanets should be able to maintain an atmosphere as massive that of Earth. In Earth's case -- with its relatively thin atmosphere -- most of the light from the Sun reaches the surface of the planet, maximizing the effect of heating throughout the atmosphere and producing a more moderate climate across the planet. By creating temperature differences at the surface, between day and night and between equator and poles, the solar heating drives winds that redistribute the mass of the atmosphere.

The impact is so significant that it overcomes the effect of tidal friction exerted by a star on whatever satellite is orbiting it, much like Earth does on the Moon.

"The Moon always shows us the same side, because the tides raised by Earth create a friction that alters its spin," said Leconte. "The Moon is in synchronous rotation with Earth because the time it takes to spin once on its axis equals the time it takes for it to orbit around Earth. That is why there is a dark side of the moon. The tidal theory, however, neglects the effects of an atmosphere."

The researchers say that a large number of known terrestrial exoplanets should not be in a state of synchronous rotation, as initially believed. While their models show that they would have a day-night cycle making them much more similar to Earth, the duration of their days could last between a few weeks and few months.

The findings are reported in the paper "Asynchronous rotation of Earth-mass planets in the habitable zone of lower-mass stars" published today in Science Express. The work was supported by grants from the Natural Sciences and Engineering Research Council of Canada.

Story Source:

The above story is based on materials provided by University of Toronto. Note: Materials may be edited for content and length.

Journal Reference:

Jérémy Leconte, Hanbo Wu, Kristen Menou, Norman Murray. Asynchronous rotation of Earth-mass planets in the habitable zone of lower-mass stars. Science, 2015 DOI: 10.1126/science.1258686

 

[CowboysFromHell]

Creationist: "The parameters on Earth are so fine-tuned to support life, that's it's highly unlikely to have happened by random chance. God must have done it."

Scientist: "Life seems to spring up wherever the conditions are right. Of all the billions of possible environments available in the universe, we will likely find life wherever the conditions are right."

 

[renesauz]

No, and I really don't believe alien life exists elsewhere either.

None at all? Its possible alien life exists right in this solar system and I would wager we find it before my life is through. Then there are billions of galaxies with billions of stars and billions of solar systems. The possibilities are out there and they are not in short demand.I think at this point, its fairly certain that alien life exists. Intelligent or not would be the question, wouldn't it?

The question centers on how life comes into existence. Sure if you believe that life somehow just happened, then that makes some sense.But my issue is twofold:

1) no one really has a decent working theory for life coming from non-life

2) the parameters needed for life as we know it are actually very, very tight. There is a good possibility that there isn't really even a decent match to earth in the universe. I know billions and billions, etc....still a whole lot of things have to be just right. Slight deviations in either direction and then its impossible for carbon based life forms to survive.

The whole concept is really centered around your approach to #1. If you believe that life got here somehow so it has to be possible, then it makes sense to believe that it is probable to have happened elsewhere. If you believe that God created it, then it seems like God would have to be the one to make the life start elsewhere and there is no indication to us that he has. Doesn't mean that he didn't, but we don't have any indication of another physical world in existence. But then again, spiritual realms are a whole other world, so I guess I could say that I believe there is "life" elsewhere, but not as we know it here on earth.

we've discovered dozens of exoplanets in the goldilocks zone already, and we've barely started looking. A planet doesn't have to be a match for Earth to sustain the life that we know.

There is a big difference between a planet that we could exist on and a planet that could form sustainable life on its own. Atmosphere, water cycles, temperature ranges, light, air cycles, radiation, gravitational force, makeup of the planets surface, makeup of the planets core....there is a lot more than just being in the right distance from the nearest star.

We have found life in some of the least hospitable spots on this planet, and bacteria in particular have been found which can fuel themselves on all sorts of odd things. The parameters under which life can exist are not quite as tight as you seem to believe.

 

[Papa Georgio]

Probably been said but I doubt we have been visited. While scientist say the possibility for life on other planets is great, the distance from those planets and the age of the universe makes it doubtful. I don't think the technology is there yet for a 2 million light year journey.