On Mar. 20, the spring equinox arrived, although here in Saskatoon we may have a hard time believing winter is truly finished. The northern hemisphere can count on increased daylight hours until late June, so whether the air is cold or the ground is covered in snow, we can still enjoy the fact that the sunrise wakes us up before we need to leave for our morning class, instead of when class is already over. We’re going to be seeing a lot more of the sun these days, so why not get to know it?
The sun is actually a class G yellow dwarf star, meaning it has a lifespan of approximately 10 billion years — don’t worry, Earth is only 4.5 billion years old, so we still have some time. The sun is 150 million kilometres away from Earth, which is roughly 580,000 times the distance from Saskatoon to Regina. In the core of the sun, the hydrogen fusion fueled core operates at 15 million degrees Celsius. On the surface, the temperature cools to about 5,500 degrees Celsius — but the surface is constantly boiling and erupting, emitting solar wind particles that reach Earth in around 40 hours and interact with our atmosphere to cause the northern lights.
Current research in the field of potentially inhabited planets in other solar systems focuses on sun-like stars, since their long lifetimes paired with significant heating power for planets in their inner solar system could theoretically allow life to evolve on a planet similar to Earth. Kepler-186f, a NASA discovery announced in 2014, is an Earth sized planet orbiting a smaller star than our sun around 500 million light-years away in the constellation Cygnus, visible just above the north eastern horizon in Saskatoon every evening after dark.