Earth-like Exoplanets - Discussions & Developments

[xXTheOneRavenXx]

Good evening all,

I thought I would start of the evening by beginning a topic that could last for quite some time. With recent developments in technology, (mainly the Kepler telescope) it is strongly believed that more and more earth-like exoplanets will be discovered. Some believe that earth is more "unique" in the universe. I personally believe otherwise. This topic can result in quite the debate, hence why I'd like to begin with HD 209458 b.

For those not familiar with this little fella, HD 209458 b is an extrasolar planet that orbits the Sun-like star HD 209458 in the constellation Pegasus every 3.5 days. Out of all other exoplanets discovered (other then Gliese 581c or d) this planet has been under more public scrutiny then any other with the announcement that Travis Barman at Lowell Observatory in Flagstaff, Arizona emission spectrum results turned up that the atmosphere of HD 209458 b contains water vapor. What is you thoughts on the possibility of this exoplanet being "earth-like"?

 

[bdewoody]

I to strongly believe there are probably thousands, if not millions, of "earthlike" planets in this galaxy. But if as most scientisits now believe we will never be able to travel at speeds greater than 0.1Xspeed of light it will make little difference to mankind's future day to day life. Maybe thousands of years in the future we will send colony ships to some of these worlds in an effort to preserve the human race.

On the other hand, if the speed of light ends up being (like the speed of sound) just an imaginary speed limit imposed by our current lack of knowledge of the big picture, mapping the location of stars that have rocky planets will be very important.

I really hope the second scenario turns out to be true but I am sure no one alive today will ever know

 

[dragon04]

What is you thoughts on the possibility of this exoplanet being "earth-like"?

With a 3.5 day orbit? Not very. With a mass of 220 Earths and a surface temperature of 1,000 degrees C? Not very. It's orbiting a "Sun-like" star at .047AU and is a gas giant with a radius about 35% greater than Jupiter. It couldn't be any less "Earth-like".

 

[xXTheOneRavenXx]

I don't normally, I guess I should know better then to copy & paste information from another site, lol. I was initially looking for another exoplanet that began with "H" that was believed to be habitable. At the moment I had forgotten it's name and at first glance I thought HD 209458 b was the one I was looking for. I did not read the entire article. So your quite right to have corrected me. Thank you.


Also, and update from the New York Times on the Gliese 581 planetary system indicates that Gliese 581 d, was initially thought to have an orbital period of 80 days, which would put it just on the outer edge of the habitable zone. Recent refinements of the data by Stephane Udry of Geneva University, show that it has an orbit of only 66.8 days, which places it well within the habitable zone. Because of its distance from Gliese 581, moreover, it must have a significant amount of water and other gases, he added. It could have oceans thousands of meters deep, he said. The team is continuing to monitor Gliese 581 in hopes that the orbital planes of the planets will bring them between the star and Earth, which will allow astronomers to learn more about their composition. Do you have anymore on this?

 

[Boris_Badenov]

In the Star Trek Universe, Vulcan orbited a Red Dwarf. Maybe we've found Vulcan after all.

 

[dragon04]

I don't normally, I guess I should know better then to copy & paste information from another site, lol. I was initially looking for another exoplanet that began with "H" that was believed to be habitable. At the moment I had forgotten it's name and at first glance I thought HD 209458 b was the one I was looking for. I did not read the entire article. So your quite right to have corrected me. Thank you.


Also, and update from the New York Times on the Gliese 581 planetary system indicates that Gliese 581 d, was initially thought to have an orbital period of 80 days, which would put it just on the outer edge of the habitable zone. Recent refinements of the data by Stephane Udry of Geneva University, show that it has an orbit of only 66.8 days, which places it well within the habitable zone. Because of its distance from Gliese 581, moreover, it must have a significant amount of water and other gases, he added. It could have oceans thousands of meters deep, he said. The team is continuing to monitor Gliese 581 in hopes that the orbital planes of the planets will bring them between the star and Earth, which will allow astronomers to learn more about their composition. Do you have anymore on this?

The only other thing I've seen about 581d is that it's estimated to be a minimum 7 Earth masses. According to an old article I read, 581 d would also be tidally locked with respect to the Primary.

 

[Robert Roy Britt]

The pace at which the various search programs are finding smaller planets farther from the host stars (i.e. in the habitable zone) has some astronomers now saying we're only a couple years away from detecting an Earth-mass world, though that might not be a habitable one because it'll likely be too close to its host star (thus easier to find). But that doesn't count Kepler, which ought to find an Earth-sized world in an Earth-like orbit before too many months or, well, what was the point of sending it up there?

But HD209458b is not habitable by life as we know it. It is just 4.4 million miles (7 million kilometers) from its star, or about 100 times closer than Jupiter is to our Sun and even closer than Mercury is to the Sun. The planet's atmosphere is thought to be about 18,000 degrees Fahrenheit (10,000 Celsius). At least 10,000 tons of material is lost every second.

More on it: http://www.space.com/scienceastronomy/s ... 30312.html

 

[xXTheOneRavenXx]

It's not an "earth-like planet, but it's a solar system around another star: http://exoplanets.org/55cnc5th.pdf
I think if full solar systems exist, then the chances of finding other "earth's" are that much better. We are finding that rocky planets do exist closer to their star then some of the Jupiter sized planets in some cases. The Jupiter size planets protect the inner planets much like our Jupiter does for us. A larger Jupiter might actually protect these rocky inner planets moreso, making the possibility of life existing that much greater.

 

[thnkrx]

Also, and update from the New York Times on the Gliese 581 planetary system indicates that Gliese 581 d, was initially thought to have an orbital period of 80 days, which would put it just on the outer edge of the habitable zone. Recent refinements of the data by Stephane Udry of Geneva University, show that it has an orbit of only 66.8 days, which places it well within the habitable zone. Because of its distance from Gliese 581, moreover, it must have a significant amount of water and other gases, he added. It could have oceans thousands of meters deep, he said. The team is continuing to monitor Gliese 581 in hopes that the orbital planes of the planets will bring them between the star and Earth, which will allow astronomers to learn more about their composition. Do you have anymore on this?

Gliese 581 D being within the habitable zone of its star is..not really accepted by those posting to the message board attached to the 'Extra-Solar Planets Encyclopedia'. Two of them ran calculations based on the new orbital period and distance and concluded it would be a frozen wasteland; a third was slightly more optimistic, citing an eccentric orbit that carried it to just barely in the fringes of the Habitable Zone. This is the only time I actually remember the people on that newsgroup having anything like a debate. If anybody is interested, I might post a link.

That said, I do see the occasional job offer posted on that site from the COROT team, apparently they are actively looking for qualified people to sift through the mountains of data collected by the satelite to confirm possible planets. The 'unoffical' claim is that COROT has discovered hundreds of planets, but a great deal of sifting remains to be done.

 

[xXTheOneRavenXx]

That might be a good link to post thnkrs. As I mentioned in the topic title, updates on these discoveries are always welcome. I know once a planet is discovered that may be another Earth, the real work begins to determine if it truly is in the habitable zone, and if it's mass, etc... make it a canidate. I know Gliese 581d has been under much debate. The last I hear was at least part of the planet could be habitable. But your information is probably more up to date then mine. Employment with CAROT eh, that could be a good career move for someone. lol, lots of paperwork though. I hear of many world observatories hiring people to sift through their data since 1996. I guess they were compiling all their data in one facility (from all the US sites), and getting people to go through it there. The main reason for the compilation was for Super Nova research. I read somewhere they were going to also check the data for exoplanets at the same time.

 

[thnkrx]

The message board attached to the Extra-Solar Planets Encyclopedia.

A word of caution - these people are the 'pros' when it comes to extra solar planets. They do not post often - sometimes a month has gone by with not no posts at all - and much of what they do post is highly technical. I read but do not post there.

http://listes.obs.ujf-grenoble.fr/wws/arc/exoplanets

 

[xXTheOneRavenXx]

Gliese 581 D being within the habitable zone of its star is..not really accepted by those posting to the message board attached to the 'Extra-Solar Planets Encyclopedia'. Two of them ran calculations based on the new orbital period and distance and concluded it would be a frozen wasteland; a third was slightly more optimistic, citing an eccentric orbit that carried it to just barely in the fringes of the Habitable Zone.

I read their debate. I think the jury is still out on Gliese 581d. They also use early Mars's location as an example to weather or not Mars is actually in the habitable zone. I believe in my study Mars actually is, however it was too small to maintain it's atmosphere, that and the lack of a satellite like our moon to help balance the poles. Because of the lack of a satellite, Mars periodically goes through erratic pole shifts. They should also consider these points as well. Many believe Mars may have actually been habitable if it wasn't for these issues.

 

[supn]

Endearing, how humanity discovers almost one exosolar planet per day.

The thought occurred to me: we have had space technology for 40 years, and we're already observing planets in our galaxy. Others in the universe with technology must have done the same.

 

[MeteorWayne]

Not quite correct. IF there are other intelligent species in the galaxy, they MIGHT have done the same. Anyone outside of our galaxy has probably already had their star die, and their civilization would almost certainly be toast by the time they could respond.

 

[supn]

In other words, we're the only technological civilization that is alive.

The Spitzer telescope, which will be dismantled soon, has ascertained that rocky planets are common in the galaxy.

Since our own little solar system already has 3-4 candidates for the existence of life (Earth, Mars, Titan, Europa), it would be absurd to think it wouldn't have happened around other stars, given the isotropy of the universe.

 

[silylene]

...The Spitzer telescope, which will be dismantled soon, has ascertained that rocky planets are common in the galaxy.....

Not really correct, a misleading choice of words.

Spitzer runs out of liq He coolant in a few days. This means that some of its infrared detectors will no longer function.
Other detectors will continue to function, as long as the scope orientation keeps them shadowed and its passive coolling design still works.

Spitzer will not be dismantled - it is far, far away in a trailing heliocentric orbit 0.1 a.u. distant from earth, and way outside of the reach of any astronauts or robot dismlantling craft. there would be no purpose to dismantle it anyways. It is better left to orbit in the solar system for the next several million years, and perhaps get visited by future space tourists.

 

[centsworth_II]

Spitzer will not be dismantled...

He probably meant the program, not the actual telescope. But as you point out, that's not correct either, as indicated by the last quote in the article:
"Spitzer: My cool years have been more than I could ask for, and I look forward to more adventures to come...."

 

[xXTheOneRavenXx]

You are quite correct. Spitzer still has some life in it yet, and for a few years anyhow.. I'm not sure I agree that we are the only intelligent species alive in the galaxy. There are numerous stars that we have detected that are in a similiar stage of their life as our own sun. I belive the only barriers between us "proving" other intelligent life exists is communication, detection & distance. As Kepler is the 1st stage in a string of new telescopes being developed, I think it's just a matter of time before another habitable planet is discovered.

 

[supn]

I agree, Raven. Now let's not see heaven from Earth, but let's see Earth from heaven.

Considering the prime youth of our technology, look at us from a distance (as from another planet). It seems obvious that we have been observed before we started staring back at the skies. Or has the galaxy started planetary observation 20 years ago?

 

[centsworth_II]

...I'm not sure I agree that we are the only intelligent species alive in the galaxy....I belive the only barriers between us "proving" other intelligent life exists is communication, detection & distance....

I think this sentiment is by far the most common one. The distance barrier may be insurmountable where communication is concerned, but not for detection. We should eventually be able to detect civilizations across the galaxy. The galaxy is (only) 100,000 light years in diameter, so most of it lies within 50,000 light years of us. Communication is a problem over those distances, but not detection (eventually).

Of course there is a window of opportunity for us to detect a civilization depending on its distance and lifespan, so no matter how good our methods get, we won't be able to detect all civilizations that have existed in the galaxy.

 

[xXTheOneRavenXx]

Unless we can somehow make a mass object become massless during transit, it will be even longer before we can travel to these other worlds without it taking decades to get there. But that's really the key to intergalactic travel isn't it. Only an object WITH mass cannot exceed the speed of light, but where will our technology in the next century take us? Who knows.

 

[centsworth_II]

Only an object WITH mass cannot exceed the speed of light...

Objects WITHOUT mass also cannot exceed the speed of light.

 

[porkchopsnapplesauce]

I might be way off, but hasn't Quantum entanglement thrown doubt on the above statement?

 

[xXTheOneRavenXx]

I might be way off, but hasn't Quantum entanglement thrown doubt on the above statement?

Yes, but however it is not quite known yet what the absolute results are. Is the speed of light actually exceeded or not.

Only an object WITH mass cannot exceed the speed of light...

Objects WITHOUT mass also cannot exceed the speed of light.

Then here is a question, inflation happened greater then the speed of light...volume-wise correct? Now carried within the inflation of space energy was carried along with it. Energy itself has no mass. I think it should be that we currently do not have the means to duplicate the driving force to break the speed of light limit with even a mass-less object or energy as it did during inflation.

 

[Mee_n_Mac]

I might be way off, but hasn't Quantum entanglement thrown doubt on the above statement?

I'm not sure that anyone understands the true nature of entanglement. Either the entangled pair operate as if they were not seperated (which I think is the leading theory) or the infomation is somehow passed between the 2 particles at much > FTL speeds. At least 10,000C if last years experiment is to be believed. This still doesn't, at least that I can see, open up a way for FTL transmission of information let alone use in some kind of space drive. I might rather hope that we could find a way to negate or reduce an objects inertia in order to more easily propel it to low C speeds (0.1 - 0.2 C). At which point Mr Sulu had better have raised some awesomely good sheilds.

http://www.nowpublic.com/tech-biz/entan ... scientists