Potentially habitable planet found

[Shadowrun]

http://news.yahoo.com/s/ap/20070425/ap_on_sc/habitable_planet

Highlights:

The planet is just the right size, might have water in liquid form, and in galactic terms is relatively nearby at 120 trillion miles away. But the star it closely orbits, known as a "red dwarf," is much smaller, dimmer and cooler than our sun.

Based on theory, 581 c should have an atmosphere, but what's in that atmosphere is still a mystery and if it's too thick that could make the planet's surface temperature too hot, Mayor said.

However, the research team believes the average temperature to be somewhere between 32 and 104 degrees and that set off celebrations among astronomers.

Until now, all 220 planets astronomers have found outside our solar system have had the "Goldilocks problem." They've been too hot, too cold or just plain too big and gaseous, like uninhabitable Jupiter.

Before you get your hopes up:

"You need more work to say it's got water or it doesn't have water," said retired NASA astronomer Steve Maran, press officer for the American Astronomical Society. "You wouldn't send a crew there assuming that when you get there, they'll have enough water to get back."

The new planet's star system is a mere 20.5 light years away, making Gliese 581 one of the 100 closest stars to Earth. It's so dim, you can't see it without a telescope, but it's somewhere in the constellation Libra, which is low in the southeastern sky during the midevening in the Northern Hemisphere.

Hawking:

"I expect there will be planets like Earth, but whether they have life is another question," said renowned astrophysicist Stephen Hawking in an interview with The Associated Press in Orlando. "We haven't been visited by little green men yet."

[thylacine]

FWIW another link:

http://news.bbc.co.uk/2/hi/science/nature/6589157.stm

[SNOWBALL]

Why are they calling this planet "relatively close"? if it's 20.5 light years away? It wouldn't be possible for any human to travel there.

[A_C_Slater]

[ QUOTE ]
Why are they calling this planet "relatively close"? if it's 20.5 light years away? It wouldn't be possible for any human to travel there.

[/ QUOTE ]

It is still in relative (cosmic) terms very very close to Earth. And it could be possible some day. And if so this may be our first destination or possibly Alpha Centauri (closest star) since it's only 4 light years away. The following link is about warp drive speculation.

http://www.nasa.gov/centers/glenn/research/warp/warp.html

[thylacine]

[ QUOTE ]
Why are they calling this planet "relatively close"? if it's 20.5 light years away? It wouldn't be possible for any human to travel there.

[/ QUOTE ]

If you shrunk the observable universe down to the size of the Earth, then this 20.5 light years would correspond to about 5 millimeters. So "relatively close" is a pretty reasonable expression.

[Metric]

[ QUOTE ]
Why are they calling this planet "relatively close"? if it's 20.5 light years away? It wouldn't be possible for any human to travel there.

[/ QUOTE ]
Within 100 to 200 years (and possibly less) we may be re-defining what constitutes "human" anyway. I agree it would be prohibitively expensive (at least) to send any humans there as of right now.

[AlexM]

[ QUOTE ]
Why are they calling this planet "relatively close"? if it's 20.5 light years away?

[/ QUOTE ]

The Milky Way is approximately 100,000 light years from edge to edge. Compared to that, 20.5 is most definitely "relatively close," and that's just our galaxy.

[ill rich]

if the universe is infinate in sice 10^6000 light years away is relatively close.

[AlexM]

[ QUOTE ]
if the universe is infinate in sice 10^6000 light years away is relatively close.

[/ QUOTE ]

Luckily, astronomers don't believe the universe to be infinite.

[Sephus]

[ QUOTE ]
if the universe is infinate in sice 10^6000 light years away is relatively close.

[/ QUOTE ]

in the same sense that any distance is relatively close.

[hmkpoker]

They have WMD's. The time to attack is NOW!

[A_C_Slater]

[ QUOTE ]
if the universe is infinate in sice 10^6000 light years away is relatively close.

[/ QUOTE ]

When these scientists are discussing habitable planets and their locales their scope of concern are only planets relegated to our own galaxy, the Milky Way. And within our own galaxy this planet is very very close to us.

[vhawk01]

[ QUOTE ]
if the universe is infinate in sice 10^6000 light years away is relatively close.

[/ QUOTE ]

If the universe is a fruitcake we're all nuts.

[cbh]

If life is discovered there what would the new theistic position be?

[Johnny Drama]

does the size of a planet meaningfully affect the habitability? I realize that a huge planet would have a stronger gravitational pull, but wouldn't any life forms on the planet adapt to the stronger gravity?

[cbh]

[ QUOTE ]
does the size of a planet meaningfully affect the habitability? I realize that a huge planet would have a stronger gravitational pull, but wouldn't any life forms on the planet adapt to the stronger gravity?

[/ QUOTE ]

I left chemistry behind me last semester, but I think greater gravity would distort pressure, which may affect some necessary elements for life, like water. I might be wrong.

[JuntMonkey]

How do we know how big the Milky Way is and when did we find out?

[A_C_Slater]

[ QUOTE ]
does the size of a planet meaningfully affect the habitability? I realize that a huge planet would have a stronger gravitational pull, but wouldn't any life forms on the planet adapt to the stronger gravity?

[/ QUOTE ]

Yes. If the gravity was strong enough some theoretical humanoid aliens would be built like the Incredible Hulk. And if it was low gravity they would be built like twigs.

[JuntMonkey]

[ QUOTE ]
If life is discovered there what would the new theistic position be?

[/ QUOTE ]

This would only be a problem for extreme literal Bible interpreters.

[theweatherman]

[ QUOTE ]
[ QUOTE ]
does the size of a planet meaningfully affect the habitability? I realize that a huge planet would have a stronger gravitational pull, but wouldn't any life forms on the planet adapt to the stronger gravity?

[/ QUOTE ]

I left chemistry behind me last semester, but I think greater gravity would distort pressure, which may affect some necessary elements for life, like water. I might be wrong.

[/ QUOTE ]

Seems like you are wrong.

Life exists at the bottom of the ocean on earth, a place with literally hundreds of tons of pressure.

[FortunaMaximus]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
does the size of a planet meaningfully affect the habitability? I realize that a huge planet would have a stronger gravitational pull, but wouldn't any life forms on the planet adapt to the stronger gravity?

[/ QUOTE ]

I left chemistry behind me last semester, but I think greater gravity would distort pressure, which may affect some necessary elements for life, like water. I might be wrong.

[/ QUOTE ]

Seems like you are wrong.

Life exists at the bottom of the ocean on earth, a place with literally hundreds of tons of pressure.

[/ QUOTE ]

Debatable, if only because life in those regions didn't necessarily develop there, but adapted to the conditions of the enviroment.

Whether life can arise with those initial conditions is another thing. There exists now at least an opportunity to find that out.

20.5 light years? Today, it'd be like a non-Sherpa trying to climb Everest in a loincloth. In a century, who knows.

[Rodney_King]

[ QUOTE ]
[ QUOTE ]
If life is discovered there what would the new theistic position be?

[/ QUOTE ]

This would only be a problem for extreme literal Bible interpreters.

[/ QUOTE ]

It obviously wouldn't be a problem for most, since they would just twist whatever is said in the Bible to the new evidence.
Here's a situation:
We go to this planet. There is life. It is extremely intelligent, and does not believe in God. Would this change theistic views at all? For one, it seems incredibly unfair that while humans got the benefit of Jesus Christ the Savior...these beings were never visited by him. Could they go to heaven? Most Christians seem to be of the position that if there is life on other planets, it is extremely similar to us. Incredibly illogical. Many even claim these other planets probably got visited by someone similar to Jesus.

[MaxWeiss]

If my grandma had wheels, she'd be a trolley.

[Insp. Clue!So?]

[ QUOTE ]
[ QUOTE ]
if the universe is infinate in sice 10^6000 light years away is relatively close.

[/ QUOTE ]

Luckily, astronomers don't believe the universe to be infinite.

[/ QUOTE ]

Some folks think it's pretty damn big nonetheless. As in 10^10^14.

Notice the lack of units. For a number that big it doesn't much matter whether you're talking inches or light years.

In any event what we can see with Hubble is just a tiny fraction of what's out there.

[MegaloMialo]

How many years would it take to reach that planet with our current spaceships?
What is the maximum speed that we can travel atm?

[Insp. Clue!So?]

[ QUOTE ]
How many years would it take to reach that planet with our current spaceships?
What is the maximum speed that we can travel atm?

[/ QUOTE ]

"Current spaceships" meaning off the shelf, I'd guess something like 100,000 miles/hour, in which case you're talking about a trip of tens of thousands of years (and of course we have no current way of making something that could reliably function for such a length of time). With some effort we could probably increase that by an order of magnitude or so in a couple of decades. There are likely some better solutions for the people of 2100 but it is still a very daunting project w/o some serious massive breakthroughs in propulsion technology, not to mention many potential unknowns.

Here's what Bob Park of the APS had to say in his "What's New" column last week:

THE HABITABLE ZONE: THE GOOD NEWS IS THEY'RE NOT COMING HERE. Humans,
fragile self-replicating chemical factories, are trapped on a tiny planet for a few dozen orbits about an undistinguished star among countless other stars in one of billions of galaxies. And yet, these insignificant specks have the audacity to imagine they can figure it all out - and maybe they can. The most compelling scientific quest is to find life to which Earthlings are not related. The first great discovery of this Century was to confirm that other stars have planets - lots of them. This week European astronomers found a planet in the habitable zone of Gliese 581, a red dwarf in the constellation Libra. The public was thrilled. We can learn a lot from here, and it's going to be exciting. Each year I ask my class of freshman physics majors if they think humans will visit another star someday. Most say yes, so we take a few minutes of each class to plan the mission. What's the closest star? How long are you prepared to travel? How big will the spaceship have to be? How will you pass the time? Anyway, we'll be able to travel much faster some day, so maybe 50 years. There's always one that insists there's gotta be a basketball court. Near the end of the semester they calculate the kinetic energy of the spacecraft to make the trip in 50 years. Hmmm, the velocity is squared. Maybe, they conclude, we could just find a way to exchange e- mails.

[CORed]

The fact that this planet orbits a red dwarf is quite significant. Red dwarfs are the most common and longest lived type of star. If habitable planets commonly orbit red dwarfs, life could be quite abundant in the universe.

[vhawk01]

[ QUOTE ]
How many years would it take to reach that planet with our current spaceships?
What is the maximum speed that we can travel atm?

[/ QUOTE ]

Neil deGrasse Tyson was on Colbert last night talking about this, and he said that the fastest ship we've ever built would take ~400,000 years to reach it.

[thylacine]

[ QUOTE ]
[ QUOTE ]
How many years would it take to reach that planet with our current spaceships?
What is the maximum speed that we can travel atm?

[/ QUOTE ]

Neil deGrasse Tyson was on Colbert last night talking about this, and he said that the fastest ship we've ever built would take ~400,000 years to reach it.

[/ QUOTE ]

If you wait, say, ten years for the technology to improve, then there'd probably be a ship that could do it in ~300,000 years.

(etc.)

[PairTheBoard]

What you need for these kinds of trips is really good mass to energy conversion and the ability to direct that energy into a propulsion system. Currently our mass to energy conversion technology is pretty primitive. Nuclear bombs only convert a tiny amount of the mass in the fissionable or fusionable material into energy. If you could convert tons of mass into energy for driving an equally massive spaceship then you could build a nice comfortable 1-g spacecraft that accelerates at a constant 1-g. It could get up to speeds approaching light speed and take advantage of the relativistic effects of slower aging for the travelers.

According to the chart here:

1-g Spacecraft (http://musr.physics.ubc.ca/~jess/p200/str/str13.html)

You could do a flyby to the OP star system 20 light years away in just 4 years onboard time. Even better, you could go 1000 times further in just 11 years onboard time. However, communication with Earth would be something else again.

PairTheBoard

[vhawk01]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
How many years would it take to reach that planet with our current spaceships?
What is the maximum speed that we can travel atm?

[/ QUOTE ]

Neil deGrasse Tyson was on Colbert last night talking about this, and he said that the fastest ship we've ever built would take ~400,000 years to reach it.

[/ QUOTE ]

If you wait, say, ten years for the technology to improve, then there'd probably be a ship that could do it in ~300,000 years.

(etc.)

[/ QUOTE ]

Right, I understand that. Someone asked for an estimate on how long it would take to get there, I figured basing one on current technology was as good as any. If we go the speed of light it takes considerably shorter, if we walk considerably longer.

[2OuterJitsu]

[ QUOTE ]
What you need for these kinds of trips is really good mass to energy conversion and the ability to direct that energy into a propulsion system. Currently our mass to energy conversion technology is pretty primitive. Nuclear bombs only convert a tiny amount of the mass in the fissionable or fusionable material into energy. If you could convert tons of mass into energy for driving an equally massive spaceship then you could build a nice comfortable 1-g spacecraft that accelerates at a constant 1-g. It could get up to speeds approaching light speed and take advantage of the relativistic effects of slower aging for the travelers.

According to the chart here:

1-g Spacecraft (http://musr.physics.ubc.ca/~jess/p200/str/str13.html)

You could do a flyby to the OP star system 20 light years away in just 4 years onboard time. Even better, you could go 1000 times further in just 11 years onboard time. However, communication with Earth would be something else again.

PairTheBoard

[/ QUOTE ]

Nice link.

I’ve worked out the math of travel like this some time ago (a 1-g ship could make it to Mars in ~two weeks instead of the current 6 months projected). I like his chart but I wish he included how much “earth time” passed as well. I’ll assume by maintain 1-g he’s fudging for the increase in mass as the ship approaches c. I guess I’m one of his hyper-curious “misanthropists” not interested in socializing (lol). My biggest issue with this hypothetical, is space debris. As empty as space is, I’m sure you’ll run into something inside of 25 light years. Running into a pubic hair at .05c will pretty much annihilate any material known to man.

Using E = (1/2) mass × speed^2:

A .45 (230 grain) caliber bullet traveling at 872ft/sec (265.79 m/sec) will impact with ~500 Newtons

A one gram pubic hair at .05c ~224 billion Newtons!

[Borodog]

[ QUOTE ]
A one gram pubic hair

[/ QUOTE ]

Man I do not want to meet the chick that came off of.

[CORed]

[ QUOTE ]
I agree it would be prohibitively expensive (at least) to send any humans there as of right now.

[/ QUOTE ]

Given that we have yet to send humans to Mars, I think it's safe to say you're right about that.

[MegaloMialo]

[ QUOTE ]
[ QUOTE ]
What you need for these kinds of trips is really good mass to energy conversion and the ability to direct that energy into a propulsion system. Currently our mass to energy conversion technology is pretty primitive. Nuclear bombs only convert a tiny amount of the mass in the fissionable or fusionable material into energy. If you could convert tons of mass into energy for driving an equally massive spaceship then you could build a nice comfortable 1-g spacecraft that accelerates at a constant 1-g. It could get up to speeds approaching light speed and take advantage of the relativistic effects of slower aging for the travelers.

According to the chart here:

1-g Spacecraft (http://musr.physics.ubc.ca/~jess/p200/str/str13.html)

You could do a flyby to the OP star system 20 light years away in just 4 years onboard time. Even better, you could go 1000 times further in just 11 years onboard time. However, communication with Earth would be something else again.

PairTheBoard

[/ QUOTE ]

Nice link.

I’ve worked out the math of travel like this some time ago (a 1-g ship could make it to Mars in ~two weeks instead of the current 6 months projected). I like his chart but I wish he included how much “earth time” passed as well. I’ll assume by maintain 1-g he’s fudging for the increase in mass as the ship approaches c. I guess I’m one of his hyper-curious “misanthropists” not interested in socializing (lol). My biggest issue with this hypothetical, is space debris. As empty as space is, I’m sure you’ll run into something inside of 25 light years. Running into a pubic hair at .05c will pretty much annihilate any material known to man.

Using E = (1/2) mass × speed^2:

A .45 (230 grain) caliber bullet traveling at 872ft/sec (265.79 m/sec) will impact with ~500 Newtons

A one gram pubic hair at .05c ~224 billion Newtons!



[/ QUOTE ]

Indeed interesting link.
So a pubic hair coming in contact with the ship at that speed will destroy it.
How can you possibly avoid space debris?
What kind of risks exists with ships in orbit?

[FortunaMaximus]

[ QUOTE ]
So a pubic hair coming in contact with the ship at that speed will destroy it.

[/ QUOTE ]

Yeah. Chuck Norris.

[ QUOTE ]
How can you possibly avoid space debris?

[/ QUOTE ]

You don't. It's gonna be useful stuff. Matter > energy. If it's gonna hit the ship anyway, might as well convert it.

Wiki - Bussard Ramjet (http://en.wikipedia.org/wiki/Bussard_ramjet)


[ QUOTE ]
What kind of risks exists with ships in orbit?

[/ QUOTE ]

tl;dr, both in transit and in orbit. There's a genre devoted to exactly that tho.

[PairTheBoard]

[ QUOTE ]
I wish he included how much “earth time” passed as well.

[/ QUOTE ]

I think there are other links on the same subject you can google that may do this. But I believe you can guestimate it a little, figuring the 1-g craft gets close the speed of light for most of the trip. So if it's a 20,000 light year trip it will take somewhat more than 20,000 earth years to make it.

[ QUOTE ]
I’ll assume by maintain 1-g he’s fudging for the increase in mass as the ship approaches c.

[/ QUOTE ]

For the craft and its crew, there is no change in mass. They experience near light speed in relation to earth exactly the same as if they were starting out. The same energy is needed to propel the ship so that a 200 pound man feels like he weighs 200 pounds. It's only from the Earth's time frame do they measure the onboard relativistic effects. That's why the craft never actually achieves light speed in relation to Earth.

[ QUOTE ]
My biggest issue with this hypothetical, is space debris.

[/ QUOTE ]

For the Matter-to-Energy Ram Jet FM talked about, you would need some kind of Force Field projected out in front of the craft to collect the debris. A physical Scoop would have problems when debris hit its edges.

PairTheBoard

[FortunaMaximus]

[ QUOTE ]
For the Matter-to-Energy Ram Jet FM talked about, you would need some kind of Force Field projected out in front of the craft to collect the debris. A physical Scoop would have problems when debris hit its edges.

[/ QUOTE ]

An EM field would do nicely, maybe a ring of lasers. This would mainly be the defense system, and would have little relevancy in regards to propulsion. It's protium hydrogen out there mostly, and it's not the most efficient of the hydrogen isotopes with regards to fuel usage.

I'd wager a guess the first voyages aren't gonna be at c anyway, or an appreciable majority fraction of it.

Our first interstellar incursions will be a fraction of that. Probes before people, I guess.

Propulsion methods would be interesting tho.

[illini43]

Suppose a ship could be built that would be able to travel to a distant star while carrying life in a reasonable time period, lets just say theoretically 1 year or less.

Wouldn't the Theory of Relativity effect the voyage? Let's say the people sent to a faraway planet were able to return; would Earth be completely different, would anyone still be alive who was there for the launch of the voyage?

[PairTheBoard]

[ QUOTE ]
Suppose a ship could be built that would be able to travel to a distant star while carrying life in a reasonable time period, lets just say theoretically 1 year or less.

Wouldn't the Theory of Relativity effect the voyage? Let's say the people sent to a faraway planet were able to return; would Earth be completely different, would anyone still be alive who was there for the launch of the voyage?

[/ QUOTE ]

A 1-g ship couldn't go too far in 1 year. But in 20 years of onboard time it could make a round trip of thousands of light years. Which means thousands of years would have passed on Earth by the time it got back.

PairTheBoard

[illini43]

So what is the point of trying to visit these places if no one will be on Earth if/when the travellers reach the planet?

[PairTheBoard]

[ QUOTE ]
So what is the point of trying to visit these places if no one will be on Earth if/when the travellers reach the planet?

[/ QUOTE ]

Adventure. Curiousity. And people may very well survive on Earth long into the future. It might be fun communicating with the people who will be living 10,000 years from now. What a view of Future History you would get by travelling on that ship. You would stay in continuous communication the whole way. Your Spacecraft evening news report would would cover Events of several Earth Years. You could watch a new Presidential Election every night. Think of all the Blogs you could read. Might be tough keeping up with the Scientific Journals though.

PairTheBoard

[PairTheBoard]

You know, if you skillfully managed your investments back on Earth while on the trip you could be awfully rich when you got back.

PairTheBoard

[thylacine]

[ QUOTE ]
[ QUOTE ]
So what is the point of trying to visit these places if no one will be on Earth if/when the travellers reach the planet?

[/ QUOTE ]

Adventure. Curiousity. And people may very well survive on Earth long into the future. It might be fun communicating with the people who will be living 10,000 years from now. What a view of Future History you would get by travelling on that ship. You would stay in continuous communication the whole way. Your Spacecraft evening news report would would cover Events of several Earth Years. You could watch a new Presidential Election every night. Think of all the Blogs you could read. Might be tough keeping up with the Scientific Journals though.

PairTheBoard

[/ QUOTE ]

And each new president would launch a new expedition, with improved technology, to overtake the previous one and beat them to the planet. /images/graemlins/grin.gif

[PairTheBoard]

[ QUOTE ]
[ QUOTE ]
[ QUOTE ]
So what is the point of trying to visit these places if no one will be on Earth if/when the travellers reach the planet?

[/ QUOTE ]

Adventure. Curiousity. And people may very well survive on Earth long into the future. It might be fun communicating with the people who will be living 10,000 years from now. What a view of Future History you would get by travelling on that ship. You would stay in continuous communication the whole way. Your Spacecraft evening news report would would cover Events of several Earth Years. You could watch a new Presidential Election every night. Think of all the Blogs you could read. Might be tough keeping up with the Scientific Journals though.

PairTheBoard

[/ QUOTE ]

And each new president would launch a new expedition, with improved technology, to overtake the previous one and beat them to the planet. /images/graemlins/grin.gif

[/ QUOTE ]

Maybe. But they wouldn't have as pleasant a trip if they go faster than 1-g. On the other hand, they could send ahead supplies for you. Maybe even seed the planet.

PairTheBoard

[thedude4life]

since radio transmissions travel at the speed of light i doubt we will have constant updates from the crew. or are we assuming new technology that bypasses this?