Mercury core is molten!!!!

[3488]

Surprise Slosh! Mercury's Core is Liquid <br />By Ker Than<br />Staff Writer<br />posted: 03 May 2007<br />2:00 pm ET<br /><br />Kitchen physics dictates that a raw egg will spin slower than a hard-boiled one. Scientists using this same logic have discovered the planet Mercury has a fluid core of molten iron.<br /><br />The finding, detailed in the May 4 issue of the journal Science, solves a 30-year-old mystery but raises another.<br /><br />To figure out whether Mercury's core was liquid or solid, a team of scientists led by Jean-Luc Margot at Cornell University measured small twists in the planet's rotation. They used a new technique that involved bouncing a radio signal sent from a ground telescope in California off the planet and then catching it again in West Virginia.<br /><br />After 5 years and 21 such observations, the team realized their values were twice as large as what would be expected if Mercury's core was solid.<br /><br />"The variations in Mercury's spin rate that we measured are best explained by a core that is at least partially molten," Margot said. "We have a 95 percent confidence level in this conclusion."<br /><br />A polluted core<br /><br />Mercury, named after the Roman gods' fleet-footed messenger, is the closest planet to our Sun. One year there is equal to 88 Earth-days. Mercury is thought to consist of a thin silicate mantle encasing an iron core. Because it is so small-its mass is only 5 percent of Earth's-scientists thought it cooled rapidly early in its formation, essentially freezing any liquid core it had into a solid.<br /><br />But 30 years ago, a flyby of the planet by the Mariner 10 spacecraft detected a weak magnetic field, about 1 percent as strong as Earth's, within the planet. Magnetic fields are generally associated with a dynamic molten core.<br /><br />Margot and his team speculate that sulfur or some other light element got mixed with Mercury's iron core when the planet was forming and lowered its melting temperature.<br /><br />"If you had <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[lukman]

Hard to believe... radio signals from earth will not bounce any usable signal after travelling millions of kilometers through a rough, thick and rocky terain of Mercury surface. <div class="Discussion_UserSignature"> </div>

 

[dragon04]

If Mercury's core is molten, shouldn't it have a much more significant magnetic field around it?<br /><br />Due to its proximity to the Sun, I'd assume its makeup would be of the heavier elements, and therefore should have a whopping magnetosphere. <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[docm]

The explanation is the magnetosphere is weakened by the sulfur impurities in the core, which is going to take some figuring to explain how it got so close to the sun to be incorporated. I'm not so sure radial mixing floats my boat yet. <div class="Discussion_UserSignature"> </div>

 

[nexium]

Mercury's surface only turns about 20 miles per hour compared to a bit more than 1000 miles per hour for Earth's Equator. that should reduce the magnetic field by about 50 times. Perhaps the core of Mercury is mostly osmium, platimum, tungsten, gold and urainium all of which are non-magnetic and about 2.5 times more dense than iron. That follows from densest elements closest to the sun. Neil

 

[dragon04]

<font color="yellow">Mercury's surface only turns about 20 miles per hour compared to a bit more than 1000 miles per hour for Earth's Equator. that should reduce the magnetic field by about 50 times.</font><br /><br />Excellent point. I hadn't thought of that. Thanks for pointing it out!<br /><br /><font color="yellow">Perhaps the core of Mercury is mostly osmium, platimum, tungsten, gold and urainium all of which are non-magnetic and about 2.5 times more dense than iron</font><br /><br />Again, a notion that hadn't occurred to me, but a hypothesis that makes sense.<br /><br /><br /><br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[rhm3]

Perhaps Mercury itself formed further away and migrated inward? That's an alternative way to explain the sulfur presence...and it wouldn't surprise me given what we've seen in extrasolar systems.

 

[jimcolyer]

Now we know why Mercury's core is so dense.

 

[MeteorWayne]

Huh? What do we know? <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[newmoon]

"Perhaps the core of Mercury is mostly osmium, platimum, tungsten, gold and urainium all of which are non-magnetic and about 2.5 times more dense than iron."<br /><br />No way--those are very rare elements. In contrast, sulfur is common. It's the tenth most abundant element in the universe.