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Moon Had Magnetic Field At Least a Billion Years Longer Than Thought, Says Study (theguardian.com)
While the moon has no global magnetic field nowadays, it did have one in the past and researchers believe it lasted at least a billion years longer than previously thought. The Guardian reports: Between 4.25 billion and 3.56 billion years ago, the lunar magnetic field was similar to that of the Earth. The field is thought to have been generated by the churning movement of fluids within the moon's molten core -- a sort of lunar dynamo. But scientists have long puzzled over when the magnetic field disappeared, with previous research unable to tell whether the field had disappeared completely by 3.19 billion years ago or had lingered on in a weaker form. Writing in the journal Science Advances, Sonia Tikoo, a planetary scientist and co-author of the research from Rutgers University, and colleagues from the University of California, Berkeley and Massachusetts Institute of Technology, describe how they set about unpicking the conundrum by analyzing a lunar rock brought back by the Apollo 15 mission in 1971. The sample contains fragments of basalt that had broken off larger rocks. According to a dating technique based on the ratio of different isotopes of argon, the basalt formed from lava flows about 3.3 billion years ago. These fragments are bound together in the sample by a glassy material, which the team say probably formed when some of the basalt melted following a meteorite impact. The researchers dated the formation of the glassy material to between 1 billion and 2.5 billion years ago. Crucially, the impact also melted iron-containing grains within the basalt. These crystalized again within the glassy material as it quickly cooled, capturing a record of the magnetic field of the moon at that time.
"The upshot, says Tikoo, is that the lunar dynamo was still going until somewhere between one billion and 2.5bn years ago."
Based on crystallized iron-grains in some glassy material, not very precised timing.
"Such a field is 1,000 times stronger than that measured at the moonâ(TM)s Apollo 15 landing site by astronauts, and far stronger than than would be expected from the influence of the Earthâ(TM)s magnetic field."
You are welcome.
According to the theory that the moon was formed by a collision between another planetoid (Theia) and Earth, the rotation speed of Earth was one complete revolution every 5 to 6 hours. Probably the Moon would be rotating even faster than Earth as well as being six times closer than it is now and being a glowing ball of magma.
Moonsanto
http://humansarefree.com/2015/03/is-moon-artificial-alien-base.html
http://wariscrime.com/new/the-moon-is-a-spacecraft/
just don't call it a dry run... spirit of creation provides more than enough of what we need without any greed/fear/ego motives.. how refreshing?
It had all magnetic field where I can't magnify it, a study can have get it.
"The researchers dated the formation of the glassy material to between 1 billion and 2.5 billion years ago. "
How do you go about dating something that doesn't have carbon, or layers of sediment to compare with? I'm sure there are other methods, but the article doesn't elaborate.
Just another day in Paradise
The moon doesn't have, nor has it ever had, global anything. "Global" refers to Earth, not the moon. "Lunar" refers to the moon - our moon.
The moon had a lunar magnetic field longer than we thought. It never had a global magnetic field.
You should remember to degauss your moons regularly. It's just a good maintenance habit.
If you go by conventional thinking, then magnetic fields no matter how weak, are going to do one of two things : attract, or repel.
If you subscribe to the idea that gravity alone controls the position of the moon around Earth, then the moon having a magnetic field, and yet being in orbit around the Earth for a billion years with it would mean that the magnetic field would be necessary to counteract the angular momentum around the Earth (rotating around Earth too fast) thus, magnetic attraction holding the moon in place.
Or else, the opposite, it rotates too slowly given its distance from the Earth, and magnetic repulsion prevented it crashing into Earth.
So to lose this force would mean either the moon would be pulled into the Earth, or the opposite, and fly off into the voids of space.
Only off by a billion years. Please tell me why the hell I would think they got it right THIS time if they keep missing the mark by such small numbers. They have the same problem with the earth's age. I swear in the last 30 years the earth has aged billions of years. Err its 200 million, no 1 billion, ooops its 3.5 billion, just joking guys really its 4.5 billion this time for reals.
If moon had magnetic field once, it could have had an atmosphere and perhaps ... life forms?
This deserves another, more detailed look. We are trawling Mars, because we are hoping it is not too late to find existing life there, and for Moon it almost certainly is too late, but if we could find evidence that once there were microbes on Moon, that would be a big deal.
Not widely known, but the popular theory is understood to be complete bullshit, even by the person who created the theory. As what no one is told is that the theory requires an exactly identical collision from the opposite direction and complementary angle to counter the imparted spin of the first collision. Which means, the theory everyone pushes is known to be completely wrong. It's pure fantasy. While plausible, it's pretty much improbable (impossible).
It's sadly comical that such an outlandishly impossible theory is accepted by mainstream. Really speaks to the sickness which has overtaken science and the peer review process.
"Moon Had Magnetic Field At Least a Billion Years Longer Than Thought"
But wait! How long is thought?
Garry Knight
Why do you need to counter the imparted spin? There's no particular reason to.
Besides, conservation of angular momentum and the gravitational effects of tidal bulges will both slow the spin and spiral the resulting moon outwards, as is still happening today.
... otherwise known as the double-whack theory. The same mischievous rocks comes back, and does it again!
The problem is, when all you have is gravity and collisions in your toolbox, you have to try and explain everything in terms of collisions and gravity. So when you come across a situation that you can't solve, hit it with a meteor / planetoid, and see what happens. If that doesn't work - hit it again! If that doesn't work, blame it on a black hole that's very small, and somehow disappeared now. I've heard that one before. But wait, it wasn't a black hole - it was lots of dark matter! Ah, that ol' chestnut. But they've discounted dark-matter last year. So maybe it was the illusory black hole all along? It was just cruisin' through the solar system. Ya'know. takin' care of business. Then left as quickly as it arrived.
I think we need better rational explanations than the ones offered by mainstream astronomy / astro-physics today.
So, just how long has the Moon been sentient?
I am the unwilling control for my Origin.