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Earth's Moon is a Rarity
Smivs writes "Scientists have concluded that moons like the Earth's are actually quite rare. Only 5-10% of planetary systems are likely to contain moons formed by planetary collisions. 'By the time the Earth's moon formed, when the Sun was 30 million years old, the planet formation process in our Solar System should have been approaching its end. In the latest study, Dr Gorlova's team looked at the heat signature of stars using the infrared. This allows astronomers to predict how much of that heat comes from the star itself and how much is re-emitted by dusty material encircling it.'"
This is exactly what I thought of- but I doubt a distinctive moon would be much help for future earth-hunters, since 5-10% of the entire galaxy is, um, quite a lot.
Not only are moons rare, but earth's moon is actually the fifth largest in our solar system. Considering how small our planet is and how big our moon is, I would say it's probably extremely rare to find similarities like this in the universe.
Full Tilt
I suggest you learn how to use these if you want anyone to actually attempt to read your drivel.
Seven puppies were harmed during the making of this post.
Theres 200 people in the room..10 to 20 of them have a birthmark on their left cheek... how RARE.
Theres 2000 people in the room..100 to 200 of them have a birthmark on their left cheek... how RARE.
Given distances between galaxies 5 to 10 percent seems rare, but if distance didn't matter then this percentage is hardly RARE considering the vastness of the universe, and number of galaxies.
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Not that I'm in the field, but I can't say I've heard of Earth being called a binary planet.
The centre of gravity of Pluto and its moon is somewhere between the two, so that I can understand is binary. But Earth and our moon? I'm pretty sure the centre of gravity is well beneath Earth's surface.
tl;dr version: could you provide a reference?
- RG>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
All in all I agree with your comments, they tend to be well thought out. However, you seemed to glance over the fact that mutations relevant to evolution occur during conception, not after birth.
:-P
Sure your body has lots of defenses against mutation, because like you said, if the cells just do what they want _after_ you are born, then, as you said, it falls apart very quickly.
But it is a different story when the body is still being "designed" when the DNA that makes up the new life has mutations, THAT's when evolutionary mutations occur. Radiation speeds this up as well (this is why when you get an x-ray they use led shielding to protect the family jewels).
Like I said, all in all you're on the mark, but just don't forget that we don't live in the world of teenage mutant ninja turtles where life just randomly mutates into other things after it's been born
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