Re-evaluating Bode's law of planetary magnetism
Abstract
THE popularity of the so-called magnetic Bode's law for the magnetic dipole moments of the planets1-4 persists despite the lack of any physical justification for such a law. The magnetic Bode's law takes the form of a plot of the log of the magnetic moment of a planet against the log of its angular momentum. On this plot, the planetary moments lie roughly along a straight line. But the dimensions of the planets vary widely and both the magnetic moment and angular momentum depend on high powers of these dimensions, so that the apparent correlation of the two quantities should not be surprising. On the positive side, this display illustrates the relative strengths of the magnetic moments of the planets without invoking a particular physical mechanism for the source of those fields, and thus has the advantage of being `noncontroversial'. We shall here bring up to date the magnetic Bode's law based on recent analysis of the moments of the terrestrial planets.
- Publication:
-
Nature
- Pub Date:
- March 1978
- DOI:
- 10.1038/272147a0
- Bibcode:
- 1978Natur.272..147R
- Keywords:
-
- Magnetic Moments;
- Planetary Magnetic Fields;
- Angular Momentum;
- Dipole Moments;
- Earth-Moon System;
- Jupiter (Planet);
- Lunar and Planetary Exploration; Planets;
- PLANETS;
- MAGNETIC MOMENTS;
- MAGNETIC PROPERTIES;
- EARTH;
- JUPITER;
- MERCURY;
- VENUS;
- MARS;
- EARTH-MOON SYSTEM