Our Sun is located 24-26,000 light years from the center of the Milky Way. It circles the galaxy every 225-250,000 years, at a speed of 220 kilometers per second. The sun is a medium size star, a Yellow Dwarf, G type main sequence. It’s about one million times the size of planet Earth.
Core temperature:15,000,000 °C. Surface temperature: 5,500 °C.
The sun emits a steady stream of charged particles, the solar wind, at 450 km per second. It increases in strength during active periods, every 11 years or so. Active periods are marked by an increase in sunspots. Sunspots are Earth-sized regions where intense magnetic fields prevent hot gas from reaching the surface, driving temperatures down to around 4,000°C. They often correspond to active regions.
Where magnetic activity drives the formation of coronal loops, or prominences. Solar flares. And Solar tsunamis, technically “fast-mode magnetohydrodynamical waves.” In February 2009, the Stereo spacecraft detected one that rose to 100,000 km high, and raced outward at 250 kilometers per second. It was associated with an eruption of gas and magnetic fields called a coronal mass ejection.
A CME can blast a billion tons of matter out at 10 to 12 million kilometers per hour. A CME sends a pulse of solar plasma to the limits of the solar system, where it can impact planets or spacecraft. We see its arrival in spectacular aurora. They form when solar particles rain down on Earth’s atmosphere, causing oxygen and nitrogen atoms to glow.
