The magnetic boundary between the Earth’s field and the solar wind, named the magnetopause, has a bullet-shaped front, gradually changing into a cylinder. Its cross-section is approximately circular.Distances in the magnetosphere are often measured in Earth radii (RE), with one Earth radius amounting to 6371 km or 3960 miles. In these units, the distance from the Earth’s center to the “nose” of the magnetosphere is about 10.5 RE and to the flanks abreast of the Earth about 15 RE, while the radius of the distant tail is 25-30 RE. By way of comparison, the moon’s average distance is about 60 RE.
When solar wind flows past the Earth, it applies pressure to the magnetic field of the earth. The brunt of the solar wind pressure is exerted on the field, compressing it. Only the restorative pressure of the magnetic field pushes against the solar wind, and a rough balance of these pressures occurs. Like imaginary football scrimage line, this balance moves towards the earth when the solar wind pressure increases, and it moves outwards toward the sun as the solar wind pressure . This scrimage line is called the magnetopause boundary.
Distances in the magnetosphere are often measured in Earth radii (RE), with one Earth radius amounting to 6371 km or 3960 miles. In these units, the distance from the Earth’s center to the “nose” of the magnetosphere is about 10.5 RE and to the flanks abreast of the Earth about 15 RE, while the radius of the distant tail is 25-30 RE. By way of comparison, the moon’s average distance is about 60 RE.
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