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New telescope as big as Earth itself!
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jefhatfield:
I think you missed the point of my first post. I was wondering why you think that the discovery of an alien civilization would "show that there is a god or at least a higher power in the universe". I'll try to make myself more clear next time
Just because an alien civilization exists, it doesn't mean that they were put there by a god or a higher power. Perhaps they evolved, in that same way that many people believe life on Earth evolved.
jefhatfield:
I think you missed the point of my first post. I was wondering why you think that the discovery of an alien civilization would "show that there is a god or at least a higher power in the universe". I'll try to make myself more clear next time
Just because an alien civilization exists, it doesn't mean that they were put there by a god or a higher power. Perhaps they evolved, in that same way that many people believe life on Earth evolved.
Re: question
That's just a matter of convention really. Both mostly originate in science fiction. "Earthlings" was generally used in older SF, usually by highly advanced aliens as a condescending identifier for humans. "Terrans" is a little more dignified, but it remains to be seen what people would actually use.
The definition of "planet" is necessarily ambiguous. Planetary science is in its infancy, but I don't think atmosphere is part of the qualification. Such a restriction might disqualify Pluto, which only has a faint atmosphere near perihelion. For much of its orbit, Pluto's atmosphere condenses and freezes on the surface. And what we call an "atmosphere" on Mercury is composed mostly of atoms blasted from the surface by solar radiation, which are fairly quickly swept into space. The best current definition of "planet" I could find was "an object orbiting a star which is not itself a star but is bigger than an asteroid." This definition doesn't settle the matter if you want to bring the notion of binary planet systems into it.
This actually just isn't true. The Earth and the Moon are "tidally locked," which is an interesting phenomenon caused by the gravitational attraction the two bodies have for each other. Their size and proximity means that the gravitational forces on the "near" sides of the bodies are much stronger than the forces on the "far" sides. This has the effect of slightly "stretching" both bodies along their common axis and making the near sides heavier relative to each other. To oversimplify, think of a dart. You can spin it end over end in the air, but it's going to land point-down. In the planetary case, the same forces that cause that alignment are also causing the "heavy end." It takes time for gravity to overcome angular momentum, but in the case of the Moon, that has already happened.
But that isn't to say that the Earth/Moon system has reached equilibrium. The same forces are also acting upon the Earth. You can observe oceanic tides easily, but tides also occur in the solid parts of the Earth's crust and interior. The gravitational effect of the moon is gradually slowing the rotation of the Earth. It just takes longer because the Earth is more massive. Eventually this effect will cause the Earth's rotational period to match the Moon's period of revolution, and the Earth will always present the same face to the Moon, just as the Moon always presents the same face to the Earth. After that point you'd have to add energy to the system to force a further slowdown in the rotation of either body.
That's just a matter of convention really. Both mostly originate in science fiction. "Earthlings" was generally used in older SF, usually by highly advanced aliens as a condescending identifier for humans. "Terrans" is a little more dignified, but it remains to be seen what people would actually use.
The definition of "planet" is necessarily ambiguous. Planetary science is in its infancy, but I don't think atmosphere is part of the qualification. Such a restriction might disqualify Pluto, which only has a faint atmosphere near perihelion. For much of its orbit, Pluto's atmosphere condenses and freezes on the surface. And what we call an "atmosphere" on Mercury is composed mostly of atoms blasted from the surface by solar radiation, which are fairly quickly swept into space. The best current definition of "planet" I could find was "an object orbiting a star which is not itself a star but is bigger than an asteroid." This definition doesn't settle the matter if you want to bring the notion of binary planet systems into it.
This actually just isn't true. The Earth and the Moon are "tidally locked," which is an interesting phenomenon caused by the gravitational attraction the two bodies have for each other. Their size and proximity means that the gravitational forces on the "near" sides of the bodies are much stronger than the forces on the "far" sides. This has the effect of slightly "stretching" both bodies along their common axis and making the near sides heavier relative to each other. To oversimplify, think of a dart. You can spin it end over end in the air, but it's going to land point-down. In the planetary case, the same forces that cause that alignment are also causing the "heavy end." It takes time for gravity to overcome angular momentum, but in the case of the Moon, that has already happened.
But that isn't to say that the Earth/Moon system has reached equilibrium. The same forces are also acting upon the Earth. You can observe oceanic tides easily, but tides also occur in the solid parts of the Earth's crust and interior. The gravitational effect of the moon is gradually slowing the rotation of the Earth. It just takes longer because the Earth is more massive. Eventually this effect will cause the Earth's rotational period to match the Moon's period of revolution, and the Earth will always present the same face to the Moon, just as the Moon always presents the same face to the Earth. After that point you'd have to add energy to the system to force a further slowdown in the rotation of either body.
"This actually just isn't true. The Earth and the Moon are "tidally locked," which is an interesting phenomenon caused by the gravitational attraction the two bodies have for each other. Their size and proximity means that the gravitational forces on the "near" sides of the bodies are much stronger than the forces on the "far" sides. This has the effect of slightly "stretching" both bodies along their common axis and making the near sides heavier relative to each other. To oversimplify, think of a dart. You can spin it end over end in the air, but it's going to land point-down. In the planetary case, the same forces that cause that alignment are also causing the "heavy end." It takes time for gravity to overcome angular momentum, but in the case of the Moon, that has already happened.
But that isn't to say that the Earth/Moon system has reached equilibrium. The same forces are also acting upon the Earth. You can observe oceanic tides easily, but tides also occur in the solid parts of the Earth's crust and interior. The gravitational effect of the moon is gradually slowing the rotation of the Earth. It just takes longer because the Earth is more massive. Eventually this effect will cause the Earth's rotational period to match the Moon's period of revolution, and the Earth will always present the same face to the Moon, just as the Moon always presents the same face to the Earth. After that point you'd have to add energy to the system to force a further slowdown in the rotation of either body."
A couple of questions about your comments.
1: I was under the impression that the moon had stopped rotating (on it's own axis) because of the earth's gravitational force. Therefore it always presents the same face to the earth. Are you saying that eventually the earths rotation arounds it's axis will slow to match the pace at which the moon orbits the earth and the two will spin (or seemingly tumble) as if joined by a straight line between them, around the sun?
2: If this is the case then would we not be able to test this theory as the earth would be experiencing measurably longer days (and nights) as it's rotation slowed? At what point will we have to adjust our calendars to account for this lunar induced slowdown of the earth, or what effect does this have on our current (Gregorian) calendars? If any? Is our recorded history long enough to have even seen the effects of this, however slight?
Coitus
But that isn't to say that the Earth/Moon system has reached equilibrium. The same forces are also acting upon the Earth. You can observe oceanic tides easily, but tides also occur in the solid parts of the Earth's crust and interior. The gravitational effect of the moon is gradually slowing the rotation of the Earth. It just takes longer because the Earth is more massive. Eventually this effect will cause the Earth's rotational period to match the Moon's period of revolution, and the Earth will always present the same face to the Moon, just as the Moon always presents the same face to the Earth. After that point you'd have to add energy to the system to force a further slowdown in the rotation of either body."
A couple of questions about your comments.
1: I was under the impression that the moon had stopped rotating (on it's own axis) because of the earth's gravitational force. Therefore it always presents the same face to the earth. Are you saying that eventually the earths rotation arounds it's axis will slow to match the pace at which the moon orbits the earth and the two will spin (or seemingly tumble) as if joined by a straight line between them, around the sun?
2: If this is the case then would we not be able to test this theory as the earth would be experiencing measurably longer days (and nights) as it's rotation slowed? At what point will we have to adjust our calendars to account for this lunar induced slowdown of the earth, or what effect does this have on our current (Gregorian) calendars? If any? Is our recorded history long enough to have even seen the effects of this, however slight?
Coitus
Coitus:
To an outside observer, the moon rotates once per orbit around the earth. For a better explaination, go here: http://www.badastronomy.com/bad/misc/moon_spin.html
We already have to adjust our calenders. The deceleration is approximately 0.7 seconds per year. Source: http://www.badastronomy.com/bad/misc/tides.html
To an outside observer, the moon rotates once per orbit around the earth. For a better explaination, go here: http://www.badastronomy.com/bad/misc/moon_spin.html
We already have to adjust our calenders. The deceleration is approximately 0.7 seconds per year. Source: http://www.badastronomy.com/bad/misc/tides.html
Re: question
Who says that there is always only one "intelligent" race on a planet? Human thinking is so self-centered and narrow-minded, that most people expect another planet with intelligent life being exactly the same way the earth is "organized": One stupid race that is controlling (at least they think that) everything. Besides co-existing "intelligent" races (nothing else was going on in Europe with the Neanderthaler and the early home sapiens) there could be other forms of civilization, like a symbiotic constellation between different intelligent life-forms, benefitting from each other without dominating.
I guess it is very human to think that there is just "one to rule them all"! It's the same reason why we always think that Aliens would look somehow human (or why do all the species from SF-shows look human in 98% of the cases?). We can't imagine things that we didn't experience or saw somehow before. Evolution is a process with infinite variables so that the outcome of the "equation" is somehow unpredictable. Considering that the environmental factors on another planet would be definately different compared to the earth (gravity, pressure, elements, temperature, pressure, etc...) it is almost impossible that life from another planet would look similar to ours in any way.
And at least it is somehow arrogant to think that potential Aliens would be only interested in the "intelligent" race on a planet and the rest doesn't count. I am pretty sure the wouldn't call us anything that disrespects the other species on earth. So if they would talk about "terrans", they probably would mean all the species from our planet.
So more likely would be a name that includes the term how the call the planet and a term that describes our species in their own language. They couldn't care less how we call ourselves. But since their way to think, their language (including grammar) and their values are probably so different to ours that we are not even able to understand the basics, we won't get at least an idea of how they would call us before we meet one... But even then, who says that we can actually hear them (again we take the human abilities to detect sound and light as a reference) or are able to communicate with them at all without technical aid like translation computers?
And maybe we don't even want to know how they call us!
groovebuster
Who says that there is always only one "intelligent" race on a planet? Human thinking is so self-centered and narrow-minded, that most people expect another planet with intelligent life being exactly the same way the earth is "organized": One stupid race that is controlling (at least they think that) everything. Besides co-existing "intelligent" races (nothing else was going on in Europe with the Neanderthaler and the early home sapiens) there could be other forms of civilization, like a symbiotic constellation between different intelligent life-forms, benefitting from each other without dominating.
I guess it is very human to think that there is just "one to rule them all"! It's the same reason why we always think that Aliens would look somehow human (or why do all the species from SF-shows look human in 98% of the cases?). We can't imagine things that we didn't experience or saw somehow before. Evolution is a process with infinite variables so that the outcome of the "equation" is somehow unpredictable. Considering that the environmental factors on another planet would be definately different compared to the earth (gravity, pressure, elements, temperature, pressure, etc...) it is almost impossible that life from another planet would look similar to ours in any way.
And at least it is somehow arrogant to think that potential Aliens would be only interested in the "intelligent" race on a planet and the rest doesn't count. I am pretty sure the wouldn't call us anything that disrespects the other species on earth. So if they would talk about "terrans", they probably would mean all the species from our planet.
So more likely would be a name that includes the term how the call the planet and a term that describes our species in their own language. They couldn't care less how we call ourselves. But since their way to think, their language (including grammar) and their values are probably so different to ours that we are not even able to understand the basics, we won't get at least an idea of how they would call us before we meet one... But even then, who says that we can actually hear them (again we take the human abilities to detect sound and light as a reference) or are able to communicate with them at all without technical aid like translation computers?
And maybe we don't even want to know how they call us!
groovebuster
groovebuster!!
where in my post did i say that humans were the only intelligent race on the planet? I never did, all i asked is what we would be called in respect to a race from mars being called martian by us, what would they call us earthling or terran. however i do agree with you that there very well may be other intelligent life on earth, as a matter of fact i believe that dolphins and whales are as intelligent as us if not more so, just because we cannot decipher their language or know whats going on in their heads does not mean they are not intelligent. I would rather be called a terran, earthling does seem dismissive in a way, "you puny earthlings" blah anyway i don't believe that all humans are intelligent to begin with, we are still a very primitve race, definitely not ready to join the interstellar community, if one exists. there are a ton of things that need to be overcome b4 we can call ourselves enlightened. also i just made a startling comparison, steve from those stupid dell commercials, could that be mike dell's way of making fun of our beloved steve jobs?
where in my post did i say that humans were the only intelligent race on the planet? I never did, all i asked is what we would be called in respect to a race from mars being called martian by us, what would they call us earthling or terran. however i do agree with you that there very well may be other intelligent life on earth, as a matter of fact i believe that dolphins and whales are as intelligent as us if not more so, just because we cannot decipher their language or know whats going on in their heads does not mean they are not intelligent. I would rather be called a terran, earthling does seem dismissive in a way, "you puny earthlings" blah anyway i don't believe that all humans are intelligent to begin with, we are still a very primitve race, definitely not ready to join the interstellar community, if one exists. there are a ton of things that need to be overcome b4 we can call ourselves enlightened. also i just made a startling comparison, steve from those stupid dell commercials, could that be mike dell's way of making fun of our beloved steve jobs?
Part of this question was answered by "PCUser". If you now understand that the moon rotates once approximitely every 2 weeks the cycle of the moon then you can also understand what will eventually happen to the earth. Eventually it will become tidally locked with the Sun so that only one face faces the sun. But before that happens something big will probably hit us screwing up the orbit and spin and everything.
Re: groovebuster!!
Since I am located in Germany I never saw the Dell commercials... what are they about?
groovebuster
Since I am located in Germany I never saw the Dell commercials... what are they about?
groovebuster
Forget about alien races from other planets and what they'd be called. If the human race colonizes other planets (Mars, the Moon, Moons of Jupiter, etc.) the people who get born and raised there will be called Martians, Moonlings or what ever is decided by the people at the time. As for people on earth, well, we'll have to wait until a distinction is necessary. Until then, we're all humans, as far as I see it.
D
D
We will always all be called humans unless we choose to genetically alter ourselves to better suit our environment on another planet. If we are simply just living on another planet someone who is born there will still be human because that is there species but there race will be based on where they are from. I.E. Asians are from Asia but are still humans.
I agree, but my point was that there really isn't any need right now to make the distinction, so the names shouldn't really be an issue. Science Fiction and popular culture have pretty much made us Earthlings and in a few cases Terrans (calling the Earth - Terra). But no one uses Terra when refering to the planet - well, probably very few. And that's the english name - what about all the other languages and their names for the Planet?
Another reason to worry about it when we get there.
D
Another reason to worry about it when we get there.
D
Agreed. This is a useless train of thought that's on the verge of derailing after hitting a car at a crossing.
But back to topic, StarryNightPro (and all the other Starry Night Astronomy Software) is coming out with an OSX upgrade - 4.X - I've been waiting for this, pretty much the only other app that I need in OSX to never have to use OS9 again.
I use MicroProjects Equinox. It seems really good and even has a feature for night use that turns the screen red if you're out in the field with your laptop. On the other hand I think StarryNight is pretty good I'm just too cheap to pay for it so I use Equinox.
StarryNight has the red screen feature as well. Its great, I've used it maybe 4-5 times when I'm looking for something especially difficult. Its been great. The new version should also have some nice enhancements.