Life on planet Gliese?

[Gustave5436]

Sorry, you can't do that, too many petawatt hours...

Also conservation of mass. The asteroid belt has far less mass than any terrestrial planet.

 

[Leifmk]

Wont work, at best you can create a heavy CO2 atmosphere which would at least allow humans to walk on the surface with just an oxygen mask. Any oxygen you can get into the atmosphere would get blown into space and another problem is if you can heat up mars enough for liquid water you will start to lose that water to space too. Mars is too small to hold onto an atmosphere with gravity alone.

It's too small to hold on to an atmosphere for billions of years, yes. Most folks who have done calculations on the subject agree that a terraformed Mars would gradually lose most of its atmosphere and water to space, over a period of millions of years.

Now, "millions of years" is rather enough time for human civilizations to rise, thrive, fall, nuke themselves back to the stone age, rise again, re-invent World of Warcraft, etc. hundreds of times. Long enough to evolve into a different species or three. No, it wouldn't last until the Sun leaves the main sequence and toasts the inner system, at least not without periodic maintenance. But that's not the kind of timescale it has to meet in order to be useful to humans.

 

[El_Machinae]

Making Mars habitable very much only needs to be a short-term affair. While more expensive than "Marsifying humans" (brute force), it's probably much simpler to do. We could get started within the decade, if we wanted. But humans are going to be leapfrogging to asteroids and comets pretty soon after we become a space-faring species, and once cheap fusion is cracked, hydrogen is going to be the main interest anyway.

If Panspermia was true, the fact that we're here could actually increase the chance of other life being nearby.

Panspermia doesn't need to be true, even. Earth's life increases the odds of life being elsewhere in our solar system, because Earth can be the source. Scores of kilograms of rock are transferred between Earth and Mars each year, for example.

 

[Eran of Arcadia]

Isn't it mostly from Mars to Earth, though?

 

[El_Machinae]

According to Natural Transfer of Viable Microbes in Space(2000), it's 'one or two orders of magnitude less' going from Earth to Mars

 

[Leifmk]

According to Natural Transfer of Viable Microbes in Space(2000), it's 'one or two orders of magnitude less' going from Earth to Mars

Yah, Mars has a much lower escape velocity to begin with, and once a bit of matter is spaceborne it'd take much less perturbation for something beginning out by Mars to get an orbit that intersects Earth's, than the opposite.

 

[El_Machinae]

I wonder how much rock we're sending to the gas giant moons that have water in them?

 

[ParadigmShifter]

Presumably it's easier to send debris towards the sun rather than away from it.

Jupiter is a big gravity sink anyway.

 

[El_Machinae]

Jupiter is a big gravity sink anyway.

Man, that sucks.

It would be cool if one of those ice moons had microbes from Earth.

 

[J-man]

Exciting news! earth like exoplanets are likely to be very common.

http://www.wired.com/wiredscience/2010/10/exoplanet-stats/

The people who did the research looked at a lot of star (stars that did have planets and star that don't). They did a statistical analysis and although we can't earth size planets yet they concluded they must common.

They found 33 planets around 22 of the stars, some of which had already been discovered and reported by other groups, and 12 candidate planets that still need to be confirmed. Because some stars were observed more often than others, the team included a “missing-planet correction” to account statistically for planets that would probably show up with more observations.

None of these planets was actually the same mass as Earth. Astronomers’ instruments aren’t yet sensitive enough to detect such small worlds.

“But what we can do is extrapolate,” Howard said. “It involves a little bit of speculation, but we’re comfortable with that uncertainty.”

In general, small planets turned out to be much more common than large ones. The researchers extended that trend down to planets about half Earth’s mass.

 

[ParadigmShifter]

Man, that sucks.

It would be cool if one of those ice moons had microbes from Earth.

Well it's probably saved us from a few comets in it's time, so it doesn't suck that bad

 

[Bluemofia]

Eating more food gains you nothing if you cant metabolize it... Chemistry IS physics.

Well, take it this way, because you clearly didn't get what I meant when I said quantity over quality.

You (as a human) can either eat a lot of candy (high energy density food in terms of calories per gram, equivalent to high quality molecules for energy), or lots more food like vegetables, bread, fruit, etc. (low quality)

Ignoring things like vitamins and minerals, (invoke vitamin pills w/e, the point is the calories) both do fine in terms of energy balance. The one eating the candy wouldn't have to eat as much or as often (that is technically detrimental to evolution, as they don't have as strong of a driving force to venture to dangerous places to eat food and have strong natural selection pressures) compared to the one eating fruit and vegetables, but both can fundamentally get enough energy via different approaches.

The same argument can be made for non-oxygen utilizing life. Instead of having oxygen fueled, high yield per molecule reactions, they take in a lot of low yield molecules and metabolize those.

 

[PlutonianEmpire]

Exciting news! earth like exoplanets are likely to be very common.

http://www.wired.com/wiredscience/2010/10/exoplanet-stats/

The people who did the research looked at a lot of star (stars that did have planets and star that don't). They did a statistical analysis and although we can't earth size planets yet they concluded they must common.

Way, way, way, WAY overly over-optimistic, and way, way, WAY over-confident.

I really don't think habitable planets are all that common as we'd like to believe.

 

[PiTiFUL]

When people whine about money spent on preventing problems 20 years down the road what makes you think they will remotely consider even a 10,000 year investment?

I dont, and if you had read my posts you would realize that I belive we will self destruct, all for an extra ten percent profit margin (greed), we are doomed because we worship the almighty dollar... I was just pointing out what I thought was a theoretical possibility.

It's too small to hold on to an atmosphere for billions of years, yes.

Its too small to hold an atmosphere for less time then that. Also it has virtually no atmosphere right now, so we have to add an atmosphere, and that atmosphere we try to add will get blown away as we are trying to build it up. Its not like we can snap our fingers and give Mars an instant atmosphere to slowly get blown away over hundreds of thousands of years.

The same argument can be made for non-oxygen utilizing life. Instead of having oxygen fueled, high yield per molecule reactions, they take in a lot of low yield molecules and metabolize those.

...and such lifeform will be very simple as all its energy and function will be totally devoted to surviving on low yield molecules, oxygen based lifeforms evolve into higher life forms because oxygen provides more energy then is needed to simply survive. Earth had billions of years for non-oxygen life to evolve and what happened, it stagnated, without the high energy oxygen system it hit an evolutionary wall.

PS on your food analogy, did you know that the current theory on our evolotion as humans states that the high energy yield of meat and our domestication of animals for food is the reason our current civilization happened. They found that all humans who did not take that route and survived on low energy vegetables or hunting alone never advanced, and you know why, because all thier time was spent on simply surviving, they had no free time to contemplate and advance thier society so it stagnated.

Way, way, way, WAY overly over-optimistic, and way, way, WAY over-confident.

QFT, seems the need to blow things way out of proportion, from poor judgement or the desire to be heard, has permeated our whole society.

 

[Bluemofia]

...and such lifeform will be very simple as all its energy and function will be totally devoted to surviving on low yield molecules, oxygen based lifeforms evolve into higher life forms because oxygen provides more energy then is needed to simply survive. Earth had billions of years for non-oxygen life to evolve and what happened, it stagnated, without the high energy oxygen system it hit an evolutionary wall.

Not necessarily. Evolution isn't anywhere near stagnant if you are on the borders of survival. Those that evolve fastest are those systems in high strain environments, because selection is strongest there. This is a very well supported concept, as pampered organisms do not evolve very quickly. Evolution isn't like energy points left over to be spent into evolving.

After oxygen came about, it pretty much nuked everything, causing microbes to either adapt to ignore it, use it, or die. It was a huge selection pressure to survive oxygen initially, not because it suddenly was a gift to allow complex metabolism. That came later after the survivors were competing for the edge amongst themselves.

PS on your food analogy, did you know that the current theory on our evolotion as humans states that the high energy yield of meat and our domestication of animals for food is the reason our current civilization happened. They found that all humans who did not take that route and survived on low energy vegetables or hunting alone never advanced, and you know why, because all thier time was spent on simply surviving, they had no free time to contemplate and advance thier society so it stagnated.

I wouldn't say domestication of animals for food, but rather a high enough degree of specialization in farming crops allowing the populace to specialize into non-food gathering jobs. (Aztecs did not have significant domestication of animals as far as I know, and yet they had a fairly vibrant civilization before the Spanish came)

Likewise, those that have domestic food animals don't always develop great civilizations, such as Egypt, whose rise to greatness started with abandoning large scale animal domestication with the desertification of Africa, and adopted a grain based agriculture.

 

[civ_king]

I dont, and if you had read my posts you would realize that I belive we will self destruct, all for an extra ten percent profit margin (greed), we are doomed because we worship the almighty dollar... I was just pointing out what I thought was a theoretical possibility.



Its too small to hold an atmosphere for less time then that. Also it has virtually no atmosphere right now, so we have to add an atmosphere, and that atmosphere we try to add will get blown away as we are trying to build it up. Its not like we can snap our fingers and give Mars an instant atmosphere to slowly get blown away over hundreds of thousands of years.



...and such lifeform will be very simple as all its energy and function will be totally devoted to surviving on low yield molecules, oxygen based lifeforms evolve into higher life forms because oxygen provides more energy then is needed to simply survive. Earth had billions of years for non-oxygen life to evolve and what happened, it stagnated, without the high energy oxygen system it hit an evolutionary wall.

PS on your food analogy, did you know that the current theory on our evolotion as humans states that the high energy yield of meat and our domestication of animals for food is the reason our current civilization happened. They found that all humans who did not take that route and survived on low energy vegetables or hunting alone never advanced, and you know why, because all thier time was spent on simply surviving, they had no free time to contemplate and advance thier society so it stagnated.



QFT, seems the need to blow things way out of proportion, from poor judgement or the desire to be heard, has permeated our whole society.

elephant cells are more efficient energy wise than mouse cells, therefore the other life could be more efficient

 

[Millman]

This is all great feedback. You can only talk about politics specifically for so long. And lets discontinue the name-calling. It's not so important to win an argument about astronomy on one forum.

If you have an idea, a philosophy, a math equation that gets us to the planet faster go ahead and post it. You'll bedazzle the scientific community if it works.

Since we're all speculating about life I would simply argue the right set of circumstances must be met whatever they might be.

There could be a simpler gas-like lifeform on a planet somewhere that didn't take as long to evolve. You kinda have to 'imagine' a feasible situation.

Mars, Venus, and parts of Earth and many other places prove infeasability. As far as we know we could have a solar system where all nine planets but the third have life. The third could be a gas we haven't identified that supplies the other eight with the sun's heat working with it.

Unless you want to believe all gas is hydrogen based. It's a combination of many complex factors already mentioned like orbits, moons, chemicals, etc.,.

Edit-specific. We don't have enough data to guess how life could form in other places in the universe unless someone is holding back on us.

We don't even know everything about our own planet and solar system.

 

[classical_hero]

We don't even know exactly how life formed on this planet. All attempts to try and reproduce life from nothing and other forms of abiogenesis have failed. The only prove life exists on earth because we see it around us. We have been looking everywhere and we have not found any forms of life, so the first thing that has to proven is how life began to exist here on this planet.

 

[Bluemofia]

We don't even know exactly how life formed on this planet. All attempts to try and reproduce life from nothing and other forms of abiogenesis have failed. The only prove life exists on earth because we see it around us. We have been looking everywhere and we have not found any forms of life, so the first thing that has to proven is how life began to exist here on this planet.

Absence of proof is not proof of absence. Just because we are unable to reproduce it with a test tube smaller than a planet with time scales less than billions of years doesn't mean it is impossible to do so.

And no, we have not been "looking everywhere" for life. The only places not on Earth we looked for life seriously is the Moon and Mars, in a few restricted places.

The Mars one was hardly a full planet survey, in addition to the Viking tests being shown to be inaccurate due to a presence of a particular compound in the soil invalidating the initial test results. (I don't recall the compound off the top of my head, but it might be Perchlorates of some sort.)

However, we have been looking everywhere on Earth for life, and we have found it everywhere. Buried inside rocks half a mile inside the continental crust, in massively acidic lakes more acidic than battery acid, nuclear reactors, in stasis inside salt crystals that have been dated to have formed in the Triassic period (and successfully revived), deep within the Antarctic ice, hydrothermal vents of temperatures greater than 100 degrees C, the list goes on. This is why life is believed to be rather probable in the universe. A "just right" situation is unnecessary for life.

 

[peter grimes]

We don't have enough data to guess how life could form in other places in the universe unless someone is holding back on us.

That's not quite accurate. There are many ideas concerning how life might arise somewhere else.

We don't even know exactly how life formed on this planet. All attempts to try and reproduce life from nothing and other forms of abiogenesis have failed. The only prove life exists on earth because we see it around us. We have been looking everywhere and we have not found any forms of life, so the first thing that has to proven is how life began to exist here on this planet.

Lots of misunderstanding in there...
As Bluemofia mentioned, just because we don't yet know the exact chemical events that lead to life on earth doesn't mean that we have no ideas about how it could have happened. In fact, I just spent a good part of last week lurking a conference sponsored by the NASA's astrobiology institute. There were at least a half dozen talks specifically dealing with the early chemistry that could give rise to the sort of life we see around us.

And you're also wrong to say that the only proof that life exists is what we see around us. This is limited to proving that the type of life we're looking for exists around us. Life that isn't based on DNA isn't going to show up unless they're looking for chemical emissions... and if you're not testing for the right emissions, you're going to miss the signal. This is what happened with Viking - they threw out the results because they weren't expecting them.

And don't forget - they recently re-analyzed the vials from the original Miller-Urey experiment and found tons more variety than the initial analysis.

My personal opinion is that life is just about inevitable if there are certain conditions such as a rich chemistry, energy gradient, etc. And I also expect that we'll find proof of non-terrestrial life within my lifetime. What I worry about most, actually, is that we'll find DNA-based life on Mars. That would be disappointing because it would seem likely to not be an independent instance of abiogenesis, but cross-contamination from impact debris exchange.

If you're interested in the talk I watched, I recommend it highly. And there's really no point in trying to argue against Abiogenesis without familiarizing yourself with the current state of research. Spending a few hours on the conference is a good way to come up to speed.

They recorded the event, but haven't apparently posted it yet. In any event, here's the link to the main page:
http://astrobiology.nasa.gov/nai/ool-www/