And there was a comprehensive story in
New Scientist magazine this past October on “The new age of sail,” as it was headlined. The subhead: “We are on the cusp of a new type of space travel that can take us to places no rocket could ever visit.”
The article began by relating 17
th Century astronomer Johanne Kepler observing comets and seeing “that their tails always pointed away from the sun, no matter which direction they were traveling. To Kepler, it meant only one thing: the comet tails were being blown from the sun.”
Indeed, “the sun produces a wind in space” and “it can be harnessed,” said the piece. “First, there are particles of light streaming from the sun constantly, each carrying a tiny bit of momentum. Second, there is a flow of charged particles, mostly protons and electrons, also moving outwards from the sun. We call the charged particles the solar wind, but both streams are blowing a gale”—that’s in the vacuum of space.