This, however, does not mean that Mars does not have a magnetosphere; simply that it is less extensive than that of the Earth. Our entire planet is enveloped in a bubble of magnetism, which springs from …

by D. Russell Humphreys. The Moon has an external magnetic field of generally less than 0.2 nanoteslas, or less than one hundred thousandth that of Earth. The satellite has a thin oxygen atmosphere that includes O, … He grabs his gloves, parka, a fancy compass, hops on a plane and flies out over the Canadian arctic. Our planet's magnetic field is in a constant state of change, say researchers who are beginning to understand how it behaves and why. These electric currents are a result of the movement of iron.

Moon Had Its Own Magnetic Field That Died A Billion Years Ago: Study Moon lost its magnetic field billions of years ago which was probably even stronger than … Just like on Earth, the Moon's dynamo was generated by electric currents.

More secular confusion about moon’s former magnetic field www.nasa.gov Figure 1. Facts about Mars' magnetic field. The Moon does not currently have a global dipolar magnetic field and only has crustal magnetization likely acquired early in its history when a dynamo was still operating. Yes, Earth does have a magnetic tail. Above: The full Moon inside Earth's magnetic tail, March 2008.

The scientists believe that the moon was a lot closer to the Earth four billion years ago. Unlike the Earth, Mars has no inner dynamo to create a major global magnetic field. It is an extension of the same familiar magnetic field we experience when using a Boy Scout compass. The magnetosphere of Mars is far simpler and less extensive than that of the Earth. The moon appears to have lost its magnetic field after its internal dynamo ceased around one billion years ago, scientists have found. The meager magnetic field is buried within Jupiter's much larger magnetic field and would show only as a local perturbation of the field lines. A magnetic field is powerful by what is called a ‘dynamo'. This is the reason how earth's gravity helped the moon maintain its magnetic field back then. In 1969, Apollo 11 astronauts (Buzz Aldrin shown here) collected moon-surface basalt samples which turned out to have been magnetized in a magnetic field that was about as strong as earth’s. the magnetic fields would be too far away to interact (earth's magnetic field was what stimulated the moon to retain its until we got separated), but we'd get a similar magnetotail effect from deflected solar winds off of the moon, which might affect satellites, etc. A recent paper by Clèment Suavet et al. Every few years, scientist Larry Newitt of the Geological Survey of Canada goes hunting. If you picture a planet (or moon) as just a big chunk of minerals --some of them ferromagnetic-- you'd expect that planet to have a weak magnetic field, randomly distributed over its surface. The magnetic field of the Moon is very weak in comparison to that of the Earth; the major difference is the Moon does not have a dipolar magnetic field currently (as would be generated by a geodynamo in its core), so that the magnetization present is varied (see picture) and its origin is almost entirely crustal in location; so it's difficult to compare as a percentage to Earth. Ganymede's magnetic field is probably created by convection within its liquid iron core.