Interplanetary medium

[2][failed verification] The density of the interplanetary medium is very low, decreasing in inverse proportion to the square of the distance from the Sun.

[citation needed] In fact, both Fourier and Chapman's final predictions were correct: because the interplanetary medium is so rarefied, it does not exhibit thermodynamic equilibrium.

For example, it carries the Sun's magnetic field with it, is highly electrically conductive (resulting in the heliospheric current sheet), forms plasma double layers where it comes into contact with a planetary magnetosphere or at the heliopause, and exhibits filamentation (such as in aurorae).

The plasma in the interplanetary medium is also responsible for the strength of the Sun's magnetic field at the orbit of the Earth being over 100 times greater than originally anticipated.

High-energy particles from the solar wind impacting on the lunar surface also cause it to emit faintly at X-ray wavelengths.

A similar phenomenon centered at the antisolar point, gegenschein is visible in a naturally dark, moonless night sky.

Tufts University Professor of astronomy, Kenneth R. Lang, writing in 2000 noted, "Half a century ago, most people visualized our planet as a solitary sphere traveling in a cold, dark vacuum of space around the Sun".

[13] In 2002, Akasofu stated "The view that interplanetary space is a vacuum into which the Sun intermittently emitted corpuscular streams was changed radically by Ludwig Biermann (1951, 1953) who proposed on the basis of comet tails, that the Sun continuously blows its atmosphere out in all directions at supersonic speed" (Syun-Ichi Akasofu, Exploring the Secrets of the Aurora, 2002)

The heliospheric current sheet results from the influence of the Sun 's rotating magnetic field on the plasma in the interplanetary medium. [ 1 ]
The interplanetary dust cloud illuminated and visible as zodiacal light , with its parts the false dawn , [ 12 ] gegenschein and the rest of its band, which is visually crossed by the Milky Way , in this composite image of the night sky above the northern and southern hemisphere