The Moon has a weak magnetic field. ... That the Sun's magnetic field plays a large role in the current state of the Moon's field is demonstrated by the similarities (general correspondence) in the Β magnetic field vector onboard an Earth-orbiting Explorer 35 and simultaneous measurements on the ground at the Apollo 12 site.
One clue is that the Earth's magnetic field is getting
weaker. Which leads one to guess that some event caused
the Earth to gain a field, and now it is decaying.
"Right now, historic records show that the strength of the magnetic field is declining very rapidly. From a quick back-of-the-envelope prediction, in 1,500 years the field will be as weak as it's ever been and we could go into a state of polarity reversal," says Singer.
http://www.sciencedaily.com/releases/20 ... 105021.htm
The strength of the Earth's magnetic field has decreased 10 percent over the past 150 years, raising the remote possibility that it may collapse and later reverse, flipping the planet's poles for the first time in nearly a million years, scientists said Thursday.
At that rate of decline, the field could vanish altogether in 1,500 to 2,000 years, said Jeremy Bloxham of Harvard University.
http://www.space.com/scienceastronomy/e ... 31212.html
Earth's magnetic field is fading. Today it is about 10 percent weaker than it was when German mathematician Carl Friedrich Gauss started keeping tabs on it in 1845, scientists say.
http://news.nationalgeographic.com/news ... field.html
Lloyd wrote:* Keeha, at that link Lizzie said, "The Earth is hollow and has an interior sun." The first part is plausible, that the Earth has a hollow center, but probably not very large. The crystal core, also mentioned there, is also plausible, like in the center of geodes, in case Earth and other planets are formed like geodes. The idea of the interior sun that's nuclear powered and was called the black sun is highly unlikely, because geodes do not have central plasma, nor do stars very likely have central nuclear furnaces, and because the black sun clearly referred to Saturn in ancient times.
* If you found an explanation in her post of how craters reduce the magnetic field in an area, such as on Mars, please quote relevant parts. Comets likely do not form craters, but meteors, comets and asteroids can attract electrical discharges between the ionosphere and ground that result in craters on the ground. Si?
Earth's solid-iron inner core is "anisotropic"...
"Hexagonal crystals have a unique directionality," says Stixrude, "which must be aligned and oriented with Earth's spin axis for every crystal in the inner core." This led Stixrude and Cohen to try a computational experiment. If all the crystals must point in the same direction, why not one big crystal? The results, published in Science, offer the simplest, most convincing explanation yet put forward for the observed seismic data and have stirred new thinking about the inner core.
Could an iron ball 1,500 miles across be a single crystal? Unheard of until this work, the idea has prompted realization that the temperature-pressure extremes of the inner core offer ideal conditions for crystal growth. Several high-pressure laboratories have experiments planned to test these results. A strongly oriented inner core could also explain anomalies of Earth's magnetic field, such as tilted field lines near the equator.
"The fact that regions of strong magnetic field cover whole basins antipodal to the point of impact makes the hypothesis that the magnetism has something to do with these large impacts seem much firmer." These regions of strong magnetic field also create their own miniature magnetospheres several hundred kilometers across, akin to the much larger magnetospheres that surround planets like Earth and block the solar wind.
Familiar text book images that illustrate a flow of hot and highly electrically-conducting fluid at the core of the Earth are based on conjecture and could now be rendered invalid. As the flow of fluids at the Earth’s core cannot be measured or observed, theories about changes in the magnetosphere have been used, inversely, to infer the existence of such flow at the core of the Earth.
While Ryskin’s research looks only at long-term changes in the Earth’s magnetic field, he points out that, “If secular variation is caused by the ocean flow, the entire concept of the dynamo operating in the Earth’s core is called into question: there exists no other evidence of hydrodynamic flow in the core.”
Users browsing this forum: No registered users and 3 guests