Can we handle not being alone?

[Nightwing]

In reading recent posts and seeing what France is doing to peoples right to practice freedom of religion, I'm not sure we could handle another world.

What kind of bigotry or hatefulness would a being from onother world find here. To bad we won't find out in our life time. This is exciting news however. Just think of dicussing creation or philosophy with a creature so distant from our world.
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In search of Earth, new class of planets found
By Michael Coren
Tuesday, August 31, 2004 Posted: 7:27 PM EDT (2327 GMT)


Astronomers on Tuesday announced the discovery of a new -- and possibly abundant -- class of planets that has more in common with Earth than the uninhabitable gas giants previously discovered.

"We are closer to answering the question, 'Are we alone in the universe?'" said Anne Kinney, director of NASA's Universe Division, Science Mission Directorate. "We aim to answer that question by looking for planets, eventually imaging them and ultimately diagnosing the presence of life on those planets."

Astronomers found the two planets, among the smallest ever detected, orbit different stars less then 50 light years from Earth. One planet circles a red dwarf star, the most abundant in our Milky Way galaxy, igniting hope that the discoveries may just be the beginning.

"We would like to make these discoveries routine and eventually push into the 'super Earth' regime," said Geoffrey Marcy of the University of California at Berkeley, who discovered a planet orbiting working with R. Paul Butler at the Carnegie Institution of Washington.

With evidence of smaller, rocky planets growing, finding another Earth seems more likely.

"It appears that most if not the majority of the remaining 100 billion stars [in the Milky Way galaxy] have some sort of planets orbiting around them," said Butler. "We are edging closer and closer to planet systems that are like our own solar system."

Using a technique that measures the "wobble" of a star caused by a planet's gravitational pull, astronomers inferred the existence of the two extraterrestrial worlds, or exoplanets, as well as traits such as their mass, orbit and speed. The star's movement, or wobble, is found by measuring the Doppler effect on light. The wavelength of the star's light lengthens, or stretches, as it moves with the gravitational pull of the planet reveals much about the planet itself..

The announcement follows on the heels of another by Swiss planet hunters who claimed to discover another planet even smaller than the one announced on Monday. That would add another instance to the new class of planets, although astronomers at Tuesday's conference said recognition of the claim would first require acceptance by a peer-reviewed journal.

There has been an explosion in the number of astronomers scanning the skies for the telltale wobble of distant worlds. Already, about 135 large exoplanets have been discovered. By refining their methods, astronomers can now detect objects even smaller than Saturn. Eventually, they have their sights set on discovering a world the size of our own.

Both of the recently discovered planets are slightly larger than Earth, about the size of Neptune, or about 17 times the size of our planet. Because they are so close to their star, they race through an extraterrestrial "year" in a matter of days.

Beyond that, astronomers can't speculate much about their appearance. They may consist of spheres of gas like Jupiter or look like Neptune itself with a core of rock and ice surrounded by a thick atmosphere of hydrogen and helium.

Given their proximity to the sun, they could also be like a scorched rock resembling Mercury.

The first planet orbits a cool, reddish dwarf star called Gilese 436 in the Leo constellation. Meticulous observation of the star began in July 2003 and detected the planet believed to be at least 21 times the size of Earth. It completes its orbit at the blazing rate of just 2.64 days instead of Earth's 365 days.

The second planet orbits a yellow star like our own, called 55 Cancri in the constellation Cancer, and is part of the first four-planet solar system ever discovered. It is estimated to be about the size of 18 Earths in mass, orbits in 2.81 days and lies about 41 light-years from Earth.

"It's the closest analog we have for our own solar system," said Barbara McArthur, investigator of the study from the University of Texas at Austin.

The planets were discovered using ground-based observations from the W.M. Keck Observatory in Hawaii, the Lick Observatory in California and the McDonald Observatory in Texas. Archived data from the Hubble space telescope was also used.

Both studies will appear in the Astrophysical Journal in December.

NASA will launch a series of missions to find more planets in the future including the Kepler Mission, the Space Interferometry Mission and the Terrestrial Planet Finder to seek out Earth-like worlds.

"These are the three missions that NASA designed to find that pale blue dot orbiting a yellow star that might harbor life," Butler said.

[Jonas Strider]

"...finding another Earth"

Hmm, wondering if that's our problem. We are looking for something LIKE our planets. Maybe there are other planets with sentient life YET different than ours. It takes one to know another. May be by NOT being discriminating and opening up our minds to allow the unknowns and unfamiliars, may be then we will find others UNLIKE our own. Just a thought.

[Nightwing]

We could only hope.

[Donut]

Originally posted by Nightwing: In reading recent posts and seeing what France is doing to peoples right to practice freedom of religion, I'm not sure we could handle another world.

Isn't this what happens in US schools? Religion isn't allowed in schools there is it?

[Nightwing]

No, religon isn't allowed in public schools, but there is no ban on religious clothing or outward signs. However most Public school districts are making rules as to what kids can wear. It all started with the Gang boom in the 80s and it got wheels from there. The state is not passing any laws of this nature to my knowledge however.

[Grojlach]

I wonder... If I were to start a topic about the economical benefits of equipping bananas with zippers, how long would it take before it's derailed into yet another topic about religion?

[Jonas Strider]

Originally posted by Grojlach: I wonder... If I were to start a topic about the economical benefits of equipping bananas with zippers, how long would it take before it's derailed into yet another topic about religion?

Haha! Well I have heard of Holy Bananas around my office here.

[LordKathen]

Originally posted by Grojlach: I wonder... If I were to start a topic about the economical benefits of equipping bananas with zippers, how long would it take before it's derailed into yet another topic about religion?

Most likely.

[Oblivion437]

I'll make a few points about being 'alone' as it were, at least as it relates to me:

It's comfortable for certain reasons. A certainty we're alone says we're not about to be subject to random-fire from God-knows-what from God-knows-where, at any time. This is our space, and we can roam it or do stuff in it as we wish, without fear of stumbling upon something we weren't supposed to.

The problem is, it makes the universe incredibly cold. It's a prison as much as anything else if you're a solipsist. Never mind that to ingenuously arrive at such a conclusion one must be so morally bankrupt as to have lost all perspective and objectivity.

There's not much point in living, save what you choose to give it.

However, there are certain rational precepts which force this view upon us:

1. No positive proof of the contrary

2. No moral code is universal

3. No ultimate retribution

4. Bad guys can win

These things are very painful to arrive at if you don't believe in God, like me, but it's a pain you have to overcome...

[frudi_x]

there are actually some good reasons to assume only Earth-like planets could sustain life.

for one, carbon is the only element that can produce the great abundance of different complex molecules that seem to be necessary for complex life to evolve. iirc known organic compounds outnumber known unorganic compounds by about 10:1. the only other element, that could theoreticly produce a similar multitude of compounds is silicon (which has the same number of valence electrons as carbon, so they are chemically quite similar), however long chains of silicon atoms are typicly a lot more unstable than carbon chains. we can therefore reasonably assume evolution will preffer carbon based organisms to theoretical silicon based ones. luckily carbon is one of the most abundant elements in the universe, so there's enough of it around in most solar systems.

the problem is however, that most organic molecules break apart at higher temperatures, higher in this case meaning 50+°C, so this sets the limit on the surface temperature of a planet that we can expect to support carbon based life. temperatures also can't be too low, or complex organic compounds cannot form, though i don't really remember what 'too low' is in this case. there is however another sensible lower limit for temperature - the freezing point of water. running water is considered to be one of the basic requirements for life, as it's an excelent solvent for most unorganic and many organic compounds, catalysing chemical reactions between them. it is also one of the rare compunds that has it's liquid phase in the temperature range that is suitable for formation and existance of organic compounds and of those it is by far the most common (as oxygen and particularly hydrogen are both very abundant in the universe) and uniquely useful.

so, what else do we need besides carbon, water and a temperature in the 0-50°C range? well, for one we need the temperature to be in that range for enough time for complex life to develop. our only estimate for that is the time it took here on earth, so let's use a rough figure of a few billion years. that eliminates the more massive stars as the more massive the star is the faster it uses up it's nuclear fuel and dies. stars are ranked into spectral classes based on their surface temperature (which depends on mass) - O B A F G K M - ranging from the hottest and most massive O class to the coldest and smallest M class. as only F class stars and smaller live for more than a billion years it's unlikely that life could develop on O B and A class stars (which by the way, are very rare anyway).
but, a star also can't be too small as then for the planet to be sufficienlty warm it would have to be so near the star that it's rotation would be slowed down because of tidal forces. this happened to Mercury, which only turns around it's axis one and a half times in the time it takes for it to go around the Sun once. the result are extremly high temperatures on the day side and extreme cold on the night side. this eliminates M and some K class stars as candidates for life bearing planets. that's a shame, as most stars in the universe are M class.

so, we want a planet with enough carbon and water, orbiting an F, G or K class star at a right distance (so the surface temperature is in the 0-50° range). there are also further possible requirements, like the presence of a Jupiter-like gass giant that will clean up all the debris left over from the formation of the solar system (debris that would otherwise regularly hit the planet, reseting the evolutionary clock to zero), no companion stars or migrating giant planets that would perturb the orbits of the planets...

finding these planets is the ultimate goal of the planet-hunting astronomers, but our current instruments are not precise enough to find them yet. it's even doubtful that the current method for finding planets can ever be made precise enough to find other Earths. however, if NASA's and ESA's plans for the following 20 years become realised, we will have space based systems of telescopes capable of directly detecting the light from these worlds.