I think we make a big mistake to think of life as only possible on a planet identical to our earth's mass and distance from the sun. Their can be a planet with 10x's the mass of earth but have the same gravitational attraction as our earth according to the the formula for computing gravity.
Have scientists found "a new earth"???
by Nathan Natas 24 Replies latest jw friends
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Elsewhere
I think we make a big mistake to think of life as only possible on a planet identical to our earth's mass and distance from the sun. Their can be a planet with 10x's the mass of earth but have the same gravitational attraction as our earth according to the the formula for computing gravity.
The only way that could be true was if G (The universal gravitational constant) was somehow different in the region of space in the planetary system.
Here is a GREAT website to explain how this works...
http://www.physicsclassroom.com/Class/circles/U6L3c.html -
Nathan Natas
Concerning the surface gravity - I think it would be less than ten times earth gravity - not fourteen times. This is because gravity decreases with the square of the distance. If the planet is about 2.4 times the diameter of earth, 1/r^2 = 0.7; 0.7 x 14 = 9.8.
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frankiespeakin
Else,
Mass and density have to be concidered together. for instance jupitor has 318x's the mass of earth but is not as densily packed so it only has 2.54 x's the surface gravity of earth. If jupitor was the same radious as earth it would then have 318 x's the gravity of earth on it's surface.
Also we have the assumption that life needs an identical conditions or alteast similar conditions to form or exist as the planet earth. I think that their is life in many forms we are not familar with. Hey for all we know the sun can be a life form.
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Elsewhere
Concerning the surface gravity - I think it would be less than ten times earth gravity - not fourteen times. This is because gravity decreases with the square of the distance. If the planet is about 2.4 times the diameter of earth, 1/r^2 = 0.7; 0.7 x 14 = 9.8.
This would be true if one were suspended above the surface of the planet, but since the surface of the planet extends out that distance, the gravity would increase accordingly. -
Nathan Natas
Elsewhere, I think you've neglected the fact that as the planet gets bigger, the surface of the planet is further from the center of the planet. That's the d^2 part of the formula you linked to.
Thought experiment - a planet as massive as earth, but made entirely of styrofoam, which is about 1/184 the density of earth. The planet would be very large, but the same mass as earth, yet you would weight about 1/8th of what you weigh on earth because you are further from the center of the mass.
cube root of 184 = 5.69 this is the increased diameter of planet styrofoam
5.69/2 = 2.845 this is the radius of planet styrofoam
2.845^2 = 8.09 this is d^2
0.123 is the value of 1/d^2
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frankiespeakin
Else,
This would be true if one were suspended above the surface of the planet, but since the surface of the planet extends out that distance, the gravity would increase accordingly.
Actually the bigger the radious the less the gravity. For instance if you could srink a marble small enough to a certain radious it would have enough gravity to be a black hole.
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Nathan Natas
Here's a couple more links on the earthlike planet orbiting muArae, designated "planet d"
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Dis-Member
Apparently not..
Two earlier discovered Earth-like planets do not exist, new study shows.
http://rt.com/news/170668-earth-planets-gliese-scientists/
Great comment:
The hubris of 'scientists' is comical. They have long since redefined and then abandoned the definition of 'science' and have plunged completely into the realm of fairy tales and speculation, needing no proof for their theories than the existence of their theories, proclaiming posit and conjecture as hard fact.
These 'scientists' have become religious zealots with no proof whatsoever of their beliefs. -
snare&racket
A perfect example of how science works.
New evidence denounces a hypothesis? Cool that makes the null hypothesis correct, mankind learned something about a body in our galaxy thanks to science. Peer review questioned the method, new research improved the mechanism of collecting data and we learned something new whilst removing something now unlikely to be true....Welcome to the scientific method.
I prefer this constructive comment.....
"Since their discovery, numerous investigations have disputed the existence of controversial planets. Their discoverers – Steve Vogt of the University of California Santa Cruz and Paul Butler of the Carnegie Institution for Science in Washington, DC – even had to publish another paper in 2012 to reaffirm the existence of Gliese 581g. They measured the colors on the violet end of the colour spectrum emitted by calcium in a star to do their corrections.
But in the new research Robertson instead measured hydrogen-emitted red color while analyzing data in Vogt and Butler's 2012 paper. He says for a cooler, low mass stars like Gliese 581 it works better, as they do not emit much blue light. In case of Gliese 581 the new measurement has shown that the system has 3 planets – a, b, and c, all of which appeared sharper – while d and g disappeared.
“I hope this research points the way toward finding exciting new planets hidden beneath stellar signals,” Robertson said."
These people are introducing data and information for mankind that will last forever, what was your last contribution to mankind and how long will it last for?
