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Mercury May Have Molten Hot Magma at its Core
mattatwork writes "According to ScienceDaily, NASA has come to the conclusion that the planet Mercury may have a molten core after all, based on high-precision planetary radar readings. You may (or may not) remember the Mariner 10 probe making 3 passes by Mercury between March 29th, 1974, September 21st 1974 and March 16, 1975."
Mercury May Have Molten Hot Magma at its Core
Excellent. This means they'll be able to serve McDonald's apple pies when they put the first restaurant on Mercury.
The theory of relativity doesn't work right in Arkansas.
Buy the new Mercury Bar, with a molten caramel core!
No more hard frozen Mars Bars. Let the chocolatey warmth flow through you.
"Magma: Molten rock beneath the surface of the earth." http://www.google.com/search?q=define%3A+magma "Molten hot magma" If it's magma, it's molten, molten rock is pretty much definately hot.
it is quite odd that mercury has a liquid metal core but a very weak magnetic field- planetary magnetic fields form when currents flow through a liquid core- the rotating core sustains the field as on earth, the sun and jupiter but mercury's is very weak- apparently it isn't rotating much
Sigs are too short to say anything truly profound so read the above post instead.
This is compared with the recent discovery of mud-like sludge in the core of Uranus.
You know, Scott. I've been a frickin' evil doctor for 30 frickin' years, OK? Cut me some "frickin'" slack. You forget Scott. We're in a volcano. We're surrounded by liquid hot magma.
Shouldn't the title be, "Mercury May Mask a Molten Middle"?
Don't listen to this guy. Mercury is not tidally locked with the sun, but rotates very slowly at about 3 rotations for every 2 revolutions around the sun. And even more, an ocean does not act as any sort of a buffer against gravitational forces from the sun. There's just not a significant enough amount of water even on Earth to do so.
Mercury is not tidally locked with the sun, but rotates very slowly at about 3 rotations for every 2 revolutions around the sun.
I forgot my Mercury trivia; they used to think it was locked before they found the 3/2 resonance. Since the resonance is stable, rotational energy is not being affected anymore. But then that means tidal forces are still heating Mercury over a 1400 hour cycle. The heat loss from friction is probably coming out of the orbital energy making the orbit unstable.
And even more, an ocean does not act as any sort of a buffer against gravitational forces from the sun. There's just not a significant enough amount of water even on Earth to do so.
OK, so the water transmits zero torque until there's how much of it then?
Most of the torque being applied to slow the earth down is transmitted at two hydrosphere/lithosphere boundaries: the one between the inner and outer core, and the one between the crust and the oceans. This is because unlike solid rock, fluids are free to slosh around horizontally. The outer core has more mass but the moment arm and surface area are both bigger for the oceanic boundary.