|solar image spotless for the second time this month|
‘The sun goes blank again during the weakest solar cycle in more than a century’
Consequences of a solar minimum
Contrary to popular belief, solar minimum is not a period of complete quiet and inactivity as it is associated with numerous interesting changes. First, cosmic rays surge into the inner solar system with relative ease during periods of solar minimum. Galactic cosmic rays coming from outside the solar system must propagate upstream against the solar wind and a thicket of solar magnetic fields. Solar wind decreases and sun’s magnetic field weakens during solar minimums making it easier for cosmic rays to reach the Earth. This is a more dangerous time for astronauts as the increase in potent cosmic rays can easily shatter a strand of human DNA. Also, during years of lower sunspot number, the sun’s extreme ultraviolet radiation (EUV) drops and the Earth’s upper atmosphere cools and contracts. With sharply lower aerodynamic drag, satellites have less trouble staying in orbit— a good thing. On the other hand, space junk tends to accumulate, making the space around Earth a more dangerous place for astronauts.
Meteorologist Paul Dorian