With the right tools, everyone can observe the sun

Bill Logan / For The Bulletin /


Published Nov 15, 2012 at 04:00AM / Updated Nov 19, 2013 at 12:31AM

Our sun is a huge, with a diameter 109 times that of the Earth. About 1.3 million Earths can fit inside the sun. The sun’s energy comes from nuclear reactions in its core.

And while the sun gives us life, it can also be harmful and needs to be monitored closely if we are to have the opportunity to forecast any changes that might affect us. The good thing about studying the sun is that anyone can do it. Solar astronomy is one of the few remaining areas of astronomy in which amateurs can make observations that are of use to professionals without the need for expensive equipment. To watch sunspots, all one needs is a good pair of binoculars or a small refractor telescope with a solar filter. (Never, ever look at the sun through binoculars or a telescope without a good solar filter, which are available online and at specialty stores. Irreversible eye damage will occur instantly without proper filters.)

If you want to spend a bit more, you may want to consider a special hydrogen telescope. With such a scope, you’ll be able to see the sun’s surface in detail.

All of the fossil fuels that we burn — wood, oil, gasoline, coal etc. — are stored energy from the sun. The sun is a middle-aged star at 4.5 billion years old. Although the sun consumes 655 million tons of hydrogen per second, it has enough fuel to last another 4.5 billion years. The sun rotates once every 25.38 days at its equator, but once every 30 days near the poles. This “differential rotation” is the primary cause of the sun’s electrical currents, electro-magnetic disturbances and coronal mass ejections that affect Earth’s climate, communications and electrical grid.

The sun is the brightest object in the sky, with an apparent visual magnitude of -27 (full moon: -13; Venus: -4). (Apparent visual magnitude is a measure of an object’s brightness as seen from Earth, adjusted to the value it would have with no atmosphere. The brighter an object appears, the lower the value of its magnitude.)

The surface of the sun is about 10,000 degrees, but the sunspots are relatively cold, with a temperature of only 7,000 to 8,000 degrees. At a distance of 93 million miles, if we could install a light switch on the sun, it would take eight minutes, 22 seconds to see it turn off.

In the meantime, it’s fun and educational to observe the sun, with the right tools.

Would you like to get solar storm alerts? Just send me an email and I’ll add you to my list.