interesting. are these aliens the ones behind the New World Order?

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I used to think it was out of the question but after googling what the closest stars to earth were, the nearest is only 4 light years away and there are 26 total within 11 light years of earth. I know that's hella far but it's not out of the question for an advanced civilization. If mankind could develop the technology for long term journeys, I believe it would only take 12 years at a constant acceleration of 2G to reach the speed of light (or 99.9% of it)

12 years to reach the speed of light + fewer than 4 years of travelling at that speed will get you to the nearest star. Thats a 28 year round trip including 9 years of decelleration back to earth. 28 years is well within the lifespan of mankind..and aliens might live to be 500..so it could be well worth the sacrifice for them to make the journey for scientific curiosity.

Of course time travels much slower for those moving at extreme speeds and their planet will have aged 6000 years by the time they get back which makes it somewhat pointless, but still.

Damn I love this shit..time dilation blows my mind.

why is the closest star relevant? surely you mean closest planet in another solar system? i dont care how advanced the aliens are, they don't live on the sun

edit: ive just found out that the nearest known Exo-planet, Epsilon Eridani b, is 10.5 lightyears from earth. i have no idea but im guessing its not habitable.

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Last edited by pkcRAISTLIN on Apr-21-2009 at 09:53

We still don't have good technology for detecting planets. We actually don't do it by sight, but by the minor gravitational effects they have on their suns. I read that in order to detect a planet, it needs to be at least the mass of Jupiter and at a fairly close distance to the star we are observing. Thats a pretty strict criteria that means all mars/earth/venus/saturn-sized planets are invisible to our technology..even from 4 light years away.

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Originally posted by Capitalizt We still don't have good technology for detecting planets. We actually don't do it by sight, but by the minor gravitational effects they have on their suns. I read that in order to detect a planet, it needs to be at least the mass of Jupiter and at a fairly close distance to the star we are observing. Thats a pretty strict criteria that means all mars/earth/venus/saturn-sized planets are invisible to our technology..even from 4 light years away.

Its getting a little better

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NASA Planet Hunter Rockets Into Space NASA planet hunter rockets into space on historic voyage to find other Earths By MARCIA DUNN The Associated Press CAPE CANAVERAL, Fla. NASA's planet-hunting spacecraft, Kepler, rocketed into space Friday night on a historic voyage to track down other Earths in a faraway patch of the Milky Way galaxy. It's the first mission capable of answering the age-old question: Are other worlds like ours out there? Kepler, named after the German 17th century astrophysicist, set off on its unprecedented mission at 10:49 p.m., thundering into a clear sky embellished by a waxing moon. Its mission will last at least 3 1/2 years and cost $600 million. The goal is to find, if they're there, Earth-like planets circling stars in the so-called habitable zone — orbits where liquid water could be present on the surface of the planets. That would mean there are lots of places out there for life to evolve, said Kepler's principal scientist, Bill Borucki. On the other hand, "if we don't find any, it really means Earths are very rare, we might be the only extant life and, in fact, that will be the end of 'Star Trek.' " Once it's settled into an Earth-trailing orbit around the sun, Kepler will stare nonstop at 100,000 stars near the Cygnus and Lyra constellations, between 600 and 3,000 light years away. The telescope will watch for any dimming, or winks, in the stellar brightness that might be caused by orbiting planets. Astronomers already have found more than 300 planets orbiting other stars, but they're largely inhospitable gas giants like Jupiter. Kepler will be looking for smaller rocky planets akin to Earth. Kepler is designed to find hundreds of Earth-like planets if they're common and, perhaps, dozens of them in the habitable zone, Borucki said. The telescope is so powerful that from space, NASA maintains, it could detect someone in a small town turning off a porch light at night. It won't be looking for signs of life, though. That's for future spacecraft. NASA was counting on a successful launch to offset the loss 1 1/2 weeks earlier of the space agency's Orbiting Carbon Observatory. That environmental satellite ended up crashing into the Antarctic because of rocket failure. It was a different type of rocket than the one used for Kepler. ——— On the Net: NASA: http://www.nasa.gov/kepler

I really would like to know.... before I die. honestly it would be choice to even find another earth like planet. Mars is all cool and shit, but Earth Like..... that would be cool.

Good read AnotherWay83, I find the UFO topic interesting also. It would be a little sad to think that we are alone in our vast universe but judging by the number of people who over the last few hundred years (actually thousands) who have reported strange objects it may not be so sad after all.

I tend to look at it from a probability angle as there could be many explanations as to why so many people have reported UFO's.

The universe has all the ingredients to produce and sustain life. How advanced another "life" form is if it exists is anyone's guess but again I am looking at the probability angle.

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I really would like to know.... before I die. honestly it would be choice to even find another earth like planet. Mars is all cool and shit, but Earth Like..... that would be cool.

Absolutely 100% agree with you. Here is a long but very good read on the probability of life outside from ours (Earth).


The Drake Equation


The Drake equation (also known as the Green Bank equation) is a famous result in the speculative fields of xenobiology and the search for extraterrestrial intelligence.

This equation was devised by Dr. Frank Drake in the 1960s in an attempt to estimate the number of extraterrestrial civilizations in our galaxy with which we might come in contact. The main purpose of the equation is to allow scientists to quantify the uncertainty of the factors which determine the number of extraterrestrial civilizations.

The Drake equation is closely related to the Fermi paradox (for which, see below).

The Drake equation states that

N = R* � fp � ne � fl � fi � fc � L

where:

N is the number of extraterrestrial civilizations in our galaxy with which we might expect to be able to communicate and

-- R* is the rate of star creation in our galaxy

-- fp is the fraction of those stars which have planets

-- ne is average number of planets which can potentially support life per star that has planets

-- fl is the fraction of the above which actually go on to develop life

-- fi is the fraction of the above which actually go on to develop intelligent life

-- fc is the fraction of the above which are willing and able to communicate

-- L is the expected lifetime of such a civilisation

Considerable disagreement on the values of most these parameters exists, but the values used by Drake and his colleagues in 1961 are: R* = 10/year, fp = 0.5, ne = 2, fl = 1, fi = fc = 0.01, and L = 10 years. The value of R* is the least disputed. fp is more uncertain, but is still much firmer than the values following. Confidence in ne was once higher, but the discovery of numerous gas giants in close orbit with their stars has introduced doubt that life-supporting planets commonly survive the creation of their stellar systems.

In addition, most stars in our galaxy are red dwarfs which have little of the ultraviolet radiation that has contributed to the evolution of life on Earth. Instead they flare violently, mostly in X-rays - a property not conducive to life as we know it (simulations also suggest that these bursts erode planetary atmospheres). The possibility of life on moons of gas giants such as Europa adds further uncertainty to this figure.

What evidence is currently visible to humanity suggests that fl is very high; life on Earth appears to have begun almost immediately after conditions arrived in which it was possible, suggesting that abiogenesis is relatively "easy" once conditions are right. But this evidence is limited in scope, and so this term remains in considerable dispute. One piece of data which would have major impact on this term is the controversy over whether there is evidence of life on Mars. The conclusion that life on Mars developed independently from life on Earth would argue for a high value for this term.

fi, fc, and L are obviously little more than guesses. fi has been impacted by discoveries that the solar system's orbit is circular in the galaxy, at such a distance that it remains out of the spiral arms for hundreds of millions of years (evading radiation from novae). Also, Earth's very large, unusual moon appears to aid retention of hydrogen by breaking up the crust, inducing a magnetosphere by tidal heating and stirring, and stabilizing the planet's axis of rotation.

In addition while it appears that life developed soon after the formation of the earth, the Cambrian explosion in which a large variety of multicelluar life came into being occurred considerable after the formation of the earth, which suggests the possibility that special conditions were necessary for this to occur. In addition some scenarios such as the Snowball Earth or research into the extinction events have raised the possibility that life on earth is relatively fragile. Again, the controversy over life on Mars is relevant since the finding that life did form on Mars but cease to exist would affect estimates of these terms.

The well known astronomer Carl Sagan has speculated that all of the terms except for the lifetime of a civilization are relatively high, and the determining factor in whether there are large or small numbers of civilizations in the universe is the civilization lifetime, or in other words the ability of technological civilizations to avoid self-destruction. In Sagan's case, the Drake equation has been a strong motivating factor for his interest in environmental issues and his efforts to warn against the dangers of nuclear warfare.

(Note, however, that in the year 2001 a value of 50 for L can be used with exactly the same degree of confidence that Drake had in using 10 in the year 1961.)

The remarkable thing about the Drake equation is that by plugging in apparently fairly plausible values for each of the parameters above, the resultant expectant value of N is generally often >> 1. This has provided considerable motivation for the SETI movement. However, this conflicts with the currently observed value of N = 1, namely ourselves. This conflict is often called the Fermi paradox, after Enrico Fermi who first publicised the subject, and suggests that our understanding of what is a "conservative" value for some of the parameters may be overly optimistic or that some other factor is involved to suppress the development of intelligent space-faring life.

Other assumptions give values of N that are << 1, but some observers believe this is still compatible with observations due to the anthropic principle: no matter how low the probability that any given galaxy will have intelligent life in it, the galaxy that we are in must have at least one intelligent species by definition. There could be hundreds of galaxies in our galactic cluster with no intelligent life whatsoever, but of course we would not be present in those galaxies to observe this fact.

Others regard the anthropic principle as controversial, and consider the N << 1 case puzzling from the viewpoint of the Copernican principle.

Some computations of the Drake equation, given different assumptions:

R* = 10/year, fp = 0.5, ne = 2, fl = 1, fi = fc = 0.01, and L = 50 years

N = 10 � 0.5 � 2 � 1 � 0.01 � 0.01 � 50 = 0.05

Alternatively, making some more optimistic assumptions, and assuming that 10% of civilisations become willing and able to communicate, and then spread through their local star systems for 100,000 years (a very short period in geologic time):

R* = 20/year, fp = 0.1, ne = 0.5, fl = 1, fi = 0.5, fc = 0.1, and L = 100,000 years

N = 20 � 0.1 � 0.5 � 1 � 0.5 � 0.1 � 100000 = 5000

Estimates of the Drake equation parameters This section attempts to list best current estimates for the parameters of the Drake equation. Please list new estimates for these values here, giving the rationale behind the estimate and a citation to their source.

R*, the rate of star creation in our galaxy

Estimated by Drake as 10/year

fp, the fraction of those stars which have planets

Estimated by Drake as 0.5

ne, the average number of planets which can potentially support life per star that has planets

Estimated by Drake as 2

fl, the fraction of the above which actually go on to develop life

Estimated by Drake as 1

In 2002, Charles H. Lineweaver and Tamara M. Davis (at the University of New South Wales and the Australian Centre for Astrobiology) estimated fl as > 0.33 usng a statistical argument based on the length of time life took to evolve on Earth. fi, the fraction of the above which actually go on to develop intelligent life

Estimated by Drake as 0.01. Solar systems in galactic orbits with radiation exposure as low as Earth's solar system are more than 100,000 times rarer, however. fc, the fraction of the above which are willing and able to communicate

Estimated by Drake as 0.01

L, the expected lifetime of such a civilisation

Estimated by Drake as 10 years.

A lower bound on L can be estimated from the lifetime of our current civilization from the advent of radio astronomy in 1938 (dated from Grote Reber's parabolic dish radio telescope) to the current date. In 2002, this gives a lower bound on L of 64 years.

In an article in Scientific American, Michael Shermer estimated L as 420 years, based on compiling the durations of sixty historical civilizations. Using twenty-eight civilizations more recent than the Roman Empire he calculates a figure of 304 years for "modern" civilizations. Note, however, that the fall of most of these civilizations did not destroy their technology, and they were succeeded by later civilizations which carried on those technologies, so Shermer's estimates should be regarded as pessimistic.

References:

-- Charles H. Lineweaver and Tamara M. Davis, Does the Rapid Appearance of Life on Earth Suggest that Life is Common in the Universe?, arXiv:astro-ph/0205014 v1 2 May 2002

-- Michael Shermer, Why ET Hasn't Called, Scientific American, August 2002, page 21


http://www.redorbit.com/education/r.../189/index.html

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Originally posted by Capitalizt We still don't have good technology for detecting planets. We actually don't do it by sight, but by the minor gravitational effects they have on their suns. I read that in order to detect a planet, it needs to be at least the mass of Jupiter and at a fairly close distance to the star we are observing. Thats a pretty strict criteria that means all mars/earth/venus/saturn-sized planets are invisible to our technology..even from 4 light years away.

For sure, but that still isn't reason enough to assume there are any planets closer than the one already mentioned.

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After locating more than 340 planets orbiting other stars, astronomers have identified two that are the most similar to Earth so far. The most recently discovered one is almost twice as large as Earth, making it the smallest exoplanet -- for extra-solar planet -- found to date. The second one was found in 2007, but new observations have shown that it is the only exoplanet to date that orbits its star in the so-called habitable zone, where water remains a liquid. Thus, it is the only exoplanet discovered that is likely to have oceans. Intriguingly, both orbit the same star, a dwarf 20 light-years from Earth called Gliese 581, European researchers said Tuesday. The identification of the small planet "is a remarkable discovery and bodes well for our eventual discovery of a true Earth-like, habitable planet," astronomer Alan Boss of the Carnegie Institution of Washington wrote in an e-mail. It "is the most exciting discovery in exoplanets so far," added astronomer Geoffrey W. Marcy of UC Berkeley via e-mail. "It shows that nature makes such small planets, probably in large numbers." The small planet is the fourth discovered circling Gliese 581 by a team of astronomers working with the European Southern Observatory's 3.6-meter telescope at La Silla, Chile. They identified the planets by detecting and analyzing slight wobbles in the star's path as the planets orbit it. The small planet, called Gliese 581 e, has an estimated mass equal to 1.9 Earths and orbits its sun every 3.15 days, the team reported at an astronomical meeting at the University of Hertfordshire in Britain. Because it is so close to Gliese 581, it is blisteringly hot and any gases or liquids that it might have carried have long since dissipated, leaving only uninhabitable rock. In February, French astronomers said they had discovered an even smaller planet, called CoRoT-Exo-7b, that has an estimated mass equal to 1.7 Earths, circling a different star. But experts said the data for Gliese 581 e is more convincing. The other three planets in the Gliese system have masses of 16, five and seven Earths. The one with a mass of seven Earths, called 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, however, show that it has an orbit of only 66.8 days, which places it well within the habitable zone, astronomer Stephane Udry of Geneva University told the meeting. 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.

http://www.latimes.com/news/science...0,5993692.story

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Originally posted by pkcRAISTLIN For sure, but that still isn't reason enough to assume there are any planets closer than the one already mentioned.

Hmm, there are probably more pluto-sized planetettes in our own solar system we dont know about. dont see why assuming there are tons of planets within 10 light years is unreasonable

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Originally posted by Sunsnail Hmm, there are probably more pluto-sized planetettes in our own solar system we dont know about. dont see why assuming there are tons of planets within 10 light years is unreasonable

because assumptions are silly. you work with the best information that you have at the time, and at this moment in time the closest exo planet is 10.5 lightyears away

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