Are We Alone in the Universe?

[alang1216]

How many cows can live on Mars?

Do you mean today or in the future?

I've always thought Venus would be a better terraforming target.

 

[Foxfyre]

I think some combination may be the most likely scenario, if the technology becomes possible: unmanned ships sent out to do original explorations, followed by human crews to places of particular interest or where some sort of colonization/terraforming seems possible.

Population issues may end up pushing space exploration and human interstellar travel in the future.

That is my vision. Obviously Planet Earth cannot sustain an unlimited population of anything let alone resource gobbling humans. So as we humans learn to live in peace and to value and preserve life, the concept of finding new worlds to explore and populate is very appealing. And I would like to think possible.

NA$A

For millennia, Earth's human population has expanded without running into permanent limits; there's no reason it can't continue that way. For example, if Alaska had the population density of New Jersey, where the people are not packed together like sardines, Alaska would hold 700 million people. The only thing preventing that is advancement in cold-weather technology, which we should put our money in instead of childish Trekkie escapism.

Limited resources are a bigger issue in population growth than anything like cold weather technology.

That's for sure. All land area is not equal when it comes to its ability to sustain life. In Kentucky that has well watered pasture and plenty of it year round, the land can sustain about 1 cow per acre with no supplemental feeding. On the high desert of New Mexico, the ratio is generally about 12 cows per section or 1 cow for every 60 acres with no supplemental feeding. In the enormous desert area of ANWR in Alaska there are virtually no resources--little surface water, the land is not arable, little or no wildlife. Not a place anybody would want to live. There is probably some oil to be tapped there though.

But if we crowd several billion people into the most hospital places on Earth, all those places will soon be buildings and pavement and that will further deplete the resources we have. So, I am all in favor of us keeping working on technology for space travel and finding places to move to when we outgrow our wonderful planet. And considering how quickly we are developing technology now, I won't be at all surprised if that is possible within the next 100 years.

How many cows can live on Mars?

None. But visiting Mars would add much to our data base of information as well as expand our technology to make longer, more adventurous space travel more feasible and more safe. There are some who say why waste time and resources in such a venture that likely won't benefit anybody here and now. And I say what if all human species had so little curiosity about what was beyond the horizon they could see? The idea of new possibilities, new adventures, new exploration is exciting to me. I always wanted to live in the 19th Century when that was happening on a large scale. And I wish I could live in the 22nd Century when I expect all that to be happening again.

 

[Montrovant]

That is my vision. Obviously Planet Earth cannot sustain an unlimited population of anything let alone resource gobbling humans. So as we humans learn to live in peace and to value and preserve life, the concept of finding new worlds to explore and populate is very appealing. And I would like to think possible.

NA$A

For millennia, Earth's human population has expanded without running into permanent limits; there's no reason it can't continue that way. For example, if Alaska had the population density of New Jersey, where the people are not packed together like sardines, Alaska would hold 700 million people. The only thing preventing that is advancement in cold-weather technology, which we should put our money in instead of childish Trekkie escapism.

Limited resources are a bigger issue in population growth than anything like cold weather technology.

That's for sure. All land area is not equal when it comes to its ability to sustain life. In Kentucky that has well watered pasture and plenty of it year round, the land can sustain about 1 cow per acre with no supplemental feeding. On the high desert of New Mexico, the ratio is generally about 12 cows per section or 1 cow for every 60 acres with no supplemental feeding. In the enormous desert area of ANWR in Alaska there are virtually no resources--little surface water, the land is not arable, little or no wildlife. Not a place anybody would want to live. There is probably some oil to be tapped there though.

But if we crowd several billion people into the most hospital places on Earth, all those places will soon be buildings and pavement and that will further deplete the resources we have. So, I am all in favor of us keeping working on technology for space travel and finding places to move to when we outgrow our wonderful planet. And considering how quickly we are developing technology now, I won't be at all surprised if that is possible within the next 100 years.

How many cows can live on Mars?

None. But visiting Mars would add much to our data base of information as well as expand our technology to make longer, more adventurous space travel more feasible and more safe. There are some who say why waste time and resources in such a venture that likely won't benefit anybody here and now. And I say what if all human species had so little curiosity about what was beyond the horizon they could see? The idea of new possibilities, new adventures, new exploration is exciting to me. I always wanted to live in the 19th Century when that was happening on a large scale. And I wish I could live in the 22nd Century when I expect all that to be happening again.

And who knows what might be found on Mars to actually benefit humanity now? That's part of the excitement of exploration.

 

[Foxfyre]

How many cows can live on Mars?

Do you mean today or in the future?

I've always thought Venus would be a better terraforming target.

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly. In contrast daytime temperatures on Mars are pretty moderate and we could cope with the minus 100 temperatures at night--far more hospitable than the temperatures on our own moon where there is 400 degrees between light and shadow.

 

[alang1216]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

 

[Foxfyre]

How many cows can live on Mars?

Do you mean today or in the future?

I've always thought Venus would be a better terraforming target.

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly. In contrast daytime temperatures on Mars are pretty moderate and we could cope with the minus 100 temperatures at night--far more hospitable than the temperatures on our own moon where there is 400 degrees between light and shadow.

 

[alang1216]

How many cows can live on Mars?

Do you mean today or in the future?

I've always thought Venus would be a better terraforming target.

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly. In contrast daytime temperatures on Mars are pretty moderate and we could cope with the minus 100 temperatures at night--far more hospitable than the temperatures on our own moon where there is 400 degrees between light and shadow.

800+ on the surface, much more hospitable at altitude.

 

[Foxfyre]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

 

[Foxfyre]

How many cows can live on Mars?

Do you mean today or in the future?

I've always thought Venus would be a better terraforming target.

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly. In contrast daytime temperatures on Mars are pretty moderate and we could cope with the minus 100 temperatures at night--far more hospitable than the temperatures on our own moon where there is 400 degrees between light and shadow.

800+ on the surface, much more hospitable at altitude.

I don't know about that. Anyway, if we're going to go, I want to get down to the surface to see what is really there.

 

[task0778]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

 

[Windparadox]

`
While I like science fiction and am a voracious sponge when it comes to cosmic and/or quantum physics (as far as I can understand it), I give scant thought to sentient beings beyond our own. I like thinking we biped humans are the predominant life form in this galaxy.
`

 

[alang1216]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

If the bacteria could grow and reproduce exponentially they would remove the majority of the CO2 in a very short time. Once the greenhouse is under control the planet would be warmer than Mars and have plenty of oxygen derived from the CO2. Tee shirt and shorts.

 

[alang1216]

`
While I like science fiction and am a voracious sponge when it comes to cosmic and/or quantum physics (as far as I can understand it), I give scant thought to sentient beings beyond our own. I like thinking we biped humans are the predominant life form in this galaxy.
`

Quite the ego you have there.

 

[task0778]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

If the bacteria could grow and reproduce exponentially they would remove the majority of the CO2 in a very short time. Once the greenhouse is under control the planet would be warmer than Mars and have plenty of oxygen derived from the CO2. Tee shirt and shorts.

Uh-huh. It might eventually be doable but I remain a bit skeptical. Consider this:

Venus is the hottest world in the solar system. Although Venus is not the planet closest to the sun, its dense atmosphere traps heat in a runaway version of the greenhouse effect that warms Earth. As a result, temperatures on Venus reach 870 degrees Fahrenheit (465 degrees Celsius), more than hot enough to melt lead. Probes that scientists have landed there have survived only a few hours before being destroyed.

Venus has a hellish atmosphere as well, consisting mainly of carbon dioxide with clouds of sulfuric acid, and scientists have only detected trace amounts of water in the atmosphere. The atmosphere is heavier than that of any other planet, leading to a surface pressure 90 times that of Earth. Incredibly, however, early in Venus' history the planet may have been habitable, according to models from NASA researchers at the Goddard Institute for Space Studies.

The surface of Venus is extremely dry. During its evolution, ultraviolet rays from the sun evaporated water quickly, keeping it in a prolonged molten state. There is no liquid water on its surface today because the scorching heat created by its ozone-filled atmosphere would cause any to boil away. Roughly two-thirds of the Venusian surface is covered by flat, smooth plains that are marred by thousands of volcanoes, some which are still active today, ranging from about 0.5 to 150 miles (0.8 to 240 kilometers) wide, with lava flows carving long, winding canals up to more than 3,000 miles (5,000 km) in length, longer than on any other planet.

Planet Venus Facts: A Hot, Hellish & Volcanic Planet

 

[alang1216]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

If the bacteria could grow and reproduce exponentially they would remove the majority of the CO2 in a very short time. Once the greenhouse is under control the planet would be warmer than Mars and have plenty of oxygen derived from the CO2. Tee shirt and shorts.

Uh-huh. It might eventually be doable but I remain a bit skeptical. Consider this:

Venus is the hottest world in the solar system. Although Venus is not the planet closest to the sun, its dense atmosphere traps heat in a runaway version of the greenhouse effect that warms Earth. As a result, temperatures on Venus reach 870 degrees Fahrenheit (465 degrees Celsius), more than hot enough to melt lead. Probes that scientists have landed there have survived only a few hours before being destroyed.

Venus has a hellish atmosphere as well, consisting mainly of carbon dioxide with clouds of sulfuric acid, and scientists have only detected trace amounts of water in the atmosphere. The atmosphere is heavier than that of any other planet, leading to a surface pressure 90 times that of Earth. Incredibly, however, early in Venus' history the planet may have been habitable, according to models from NASA researchers at the Goddard Institute for Space Studies.

The surface of Venus is extremely dry. During its evolution, ultraviolet rays from the sun evaporated water quickly, keeping it in a prolonged molten state. There is no liquid water on its surface today because the scorching heat created by its ozone-filled atmosphere would cause any to boil away. Roughly two-thirds of the Venusian surface is covered by flat, smooth plains that are marred by thousands of volcanoes, some which are still active today, ranging from about 0.5 to 150 miles (0.8 to 240 kilometers) wide, with lava flows carving long, winding canals up to more than 3,000 miles (5,000 km) in length, longer than on any other planet.

Planet Venus Facts: A Hot, Hellish & Volcanic Planet

The issue is CO2, remove that and the greenhouse effect goes away and viola, you have a much more temperate world. The sulfuric acid can also be converted to sulfur and O2.

 

[Foxfyre]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

Actually I don't think it likely that there is another hospitable planet/moon/whatever in our solar system. I think Planet Earth is probably it--uniquely placed at the precisely beneficial distance from the sun and protected from most incoming by the larger planets out there.

That's why when I learned that warp speeds were not only scientifically obtainable but probable at some point in our future, that we would have the capability to explore outside our solar system where other planets more like Earth would likely be.

 

[Foxfyre]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

If the bacteria could grow and reproduce exponentially they would remove the majority of the CO2 in a very short time. Once the greenhouse is under control the planet would be warmer than Mars and have plenty of oxygen derived from the CO2. Tee shirt and shorts.

It sure would be interesting to find out.

 

[task0778]

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

If the bacteria could grow and reproduce exponentially they would remove the majority of the CO2 in a very short time. Once the greenhouse is under control the planet would be warmer than Mars and have plenty of oxygen derived from the CO2. Tee shirt and shorts.

Uh-huh. It might eventually be doable but I remain a bit skeptical. Consider this:

Venus is the hottest world in the solar system. Although Venus is not the planet closest to the sun, its dense atmosphere traps heat in a runaway version of the greenhouse effect that warms Earth. As a result, temperatures on Venus reach 870 degrees Fahrenheit (465 degrees Celsius), more than hot enough to melt lead. Probes that scientists have landed there have survived only a few hours before being destroyed.

Venus has a hellish atmosphere as well, consisting mainly of carbon dioxide with clouds of sulfuric acid, and scientists have only detected trace amounts of water in the atmosphere. The atmosphere is heavier than that of any other planet, leading to a surface pressure 90 times that of Earth. Incredibly, however, early in Venus' history the planet may have been habitable, according to models from NASA researchers at the Goddard Institute for Space Studies.

The surface of Venus is extremely dry. During its evolution, ultraviolet rays from the sun evaporated water quickly, keeping it in a prolonged molten state. There is no liquid water on its surface today because the scorching heat created by its ozone-filled atmosphere would cause any to boil away. Roughly two-thirds of the Venusian surface is covered by flat, smooth plains that are marred by thousands of volcanoes, some which are still active today, ranging from about 0.5 to 150 miles (0.8 to 240 kilometers) wide, with lava flows carving long, winding canals up to more than 3,000 miles (5,000 km) in length, longer than on any other planet.

Planet Venus Facts: A Hot, Hellish & Volcanic Planet

The issue is CO2, remove that and the greenhouse effect goes away and viola, you have a much more temperate world. The sulfuric acid can also be converted to sulfur and O2.

What about the surface pressure 90 times that of Earth? And the thousands of volcanoes and lava flows? Still skeptical.

 

[Foxfyre]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

If the bacteria could grow and reproduce exponentially they would remove the majority of the CO2 in a very short time. Once the greenhouse is under control the planet would be warmer than Mars and have plenty of oxygen derived from the CO2. Tee shirt and shorts.

Uh-huh. It might eventually be doable but I remain a bit skeptical. Consider this:

Venus is the hottest world in the solar system. Although Venus is not the planet closest to the sun, its dense atmosphere traps heat in a runaway version of the greenhouse effect that warms Earth. As a result, temperatures on Venus reach 870 degrees Fahrenheit (465 degrees Celsius), more than hot enough to melt lead. Probes that scientists have landed there have survived only a few hours before being destroyed.

Venus has a hellish atmosphere as well, consisting mainly of carbon dioxide with clouds of sulfuric acid, and scientists have only detected trace amounts of water in the atmosphere. The atmosphere is heavier than that of any other planet, leading to a surface pressure 90 times that of Earth. Incredibly, however, early in Venus' history the planet may have been habitable, according to models from NASA researchers at the Goddard Institute for Space Studies.

The surface of Venus is extremely dry. During its evolution, ultraviolet rays from the sun evaporated water quickly, keeping it in a prolonged molten state. There is no liquid water on its surface today because the scorching heat created by its ozone-filled atmosphere would cause any to boil away. Roughly two-thirds of the Venusian surface is covered by flat, smooth plains that are marred by thousands of volcanoes, some which are still active today, ranging from about 0.5 to 150 miles (0.8 to 240 kilometers) wide, with lava flows carving long, winding canals up to more than 3,000 miles (5,000 km) in length, longer than on any other planet.

Planet Venus Facts: A Hot, Hellish & Volcanic Planet

Very true which is why I think visiting there not a good idea. However, alang is thinking outside the box in how that hellish world could be altered with the introduction of innovative bacteria, assuming those bacteria could survive those conditions. In time it could change Venus into a much more hospitable place.

Meanwhile I hope we keep looking for other "Class M" (Star Trek) planets out there that the next generation or two might have capability to visit.

 

[task0778]

I don't know. The average daytime temperatures on Venus are thought to be 800+ fahrenheit. That would bar-b-que a steer pretty quickly.

true enough but we will soon have designer bacteria that can turn CO2 into carbon and oxygen, powered by the sun. put a small number into the Venusian atmosphere and stand back

Hmmm. That would be intriguing to watch wouldn't it. All we have to do is determine that there is no sentient life on Venus that we would be interfering with and it could be a really fun experiment.

Yeah but it could be a really long movie. Took us 3 billion years or so to evolve I think. I really don't think Venus would be a suitable place for us to colonize. Mars or a few of those moons around Jupiter or Saturn that might have water might be better choices.

Actually I don't think it likely that there is another hospitable planet/moon/whatever in our solar system. I think Planet Earth is probably it--uniquely placed at the precisely beneficial distance from the sun and protected from most incoming by the larger planets out there.

That's why when I learned that warp speeds were not only scientifically obtainable but probable at some point in our future, that we would have the capability to explore outside our solar system where other planets more like Earth would likely be.

Well, I dunno - there's a lot of work going on to build an outpost of some kind on Mars, and some people think we'll have a station there:

What do we mean when we say an environment is “habitable”? When referring to exoplanets, the term “habitability” is usually equated to whether or not liquid water can exist on the planet’s surface. But that doesn’t always answer the question of whether humans can inhabit a given environment. After all, Earth’s South Pole doesn’t have liquid water on the surface. Neither does low-Earth orbit. Yet resourceful humans have been inhabiting both locations for decades.

What about Mars? Mars is on the outer boundary of our solar system’s habitable zone, and we know what looks like briny, liquid water can exist on the surface for short periods of time. But does that really make Mars habitable? From a practical standpoint, the answer depends on what technologies we bring there to create our own artificial habitable zones on the surface.

Long-term habitation on Mars will require us to master the conversion of raw Martian materials into resources we can use to survive. Fortunately, Mars has a wealth of these materials, making it arguably the most human-habitable place in the solar system, other than the Earth itself.

Is Mars habitable? With the right technologies, yes

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Then there's Europa, one of Jupiter's moons:

NASA scientists believe that one of Jupiter's moons is the most likely place in the universe beyond the Earth that could harbour life. Europa, the sixth closest moon to the planet, is far more likely to be habitable than desert-covered Mars which has been the focus of recent US exploration, they say. It's ocean, thin shelf of ice and the presence of oxidants on Europa make it far more likely to be home to a life form than the red planet.

Read more: Jupiter's Europa moon is 'most likely to support life than the deserts of Mars', claim NASA scientists | Daily Mail Online

----

And Enceladus:

Today Earthlings came one very giant step closer to finding life elsewhere in our solar system. In the final months of its 20-year mission, the spacecraft Cassini delivered its most noteworthy revelation yet: the ocean of Enceladus, a moon of Saturn, is releasing hydrogen, an energy source for some microorganisms. In other words, that ocean is inhabitable. “Enceladus,” says Cornell University astrophysicist Jonathan Lunine, “is the place to go to look for life.”

The ocean—made of liquid water and resembling a hybrid of the Atlantic Ocean, a desert mineral lake and the fluid found near hydrothermal vents—covers the entire surface of this moon. A thick shell of ice surrounds the entire body of water, though, leaving it dark and frigid. But something happening inside that ocean is strong enough to break through those miles of ice. At the moon’s southern pole, a geyser-like plume spews water vapor, ice, salt and a mix of gases hundreds of miles into space at a force of 800 miles per hour.

Cassini spacecraft delivers biggest revelation yet: A moon of Saturn is habitable