Week of August 6-12, 2017
It's been quite a while since we in North America have enjoyed an eclipse of the sun — partial or otherwise. But one will occur on Aug. 21, and you won't want to miss it.
A solar eclipse occurs when the moon in its orbit passes between the Earth and the sun and temporarily blocks our star from view.
What you see, however, will depend on your location. Sky watchers throughout North America, for example, will see varying degrees of a partial solar eclipse, which is interesting and fun to watch but nothing terribly dramatic.
You can use this interactive map to find eclipse times and percentages for your location: eclipse2017.nasa.gov/sites/default/files/interactive_map/index.html. Simply zoom in and click on your location to see all the details you'll need. Keep in mind that the times presented here are in Universal Time, or UTC, and you'll need to convert them to your local time (earthsky.org/astronomy-essentials/universal-time).
Only those along a narrow strip of land from Oregon to South Carolina will experience a rare and spectacular total solar eclipse. If you plan to journey there — and I highly recommend it — keep in mind that tens of millions of others will be doing the same, so be sure to allow yourself a few extra days before and after Aug. 21.
Is it worth the effort? Well, consider that seeing even a 99 percent partial eclipse versus totality is like almost winning the lottery versus winning the lottery. Any questions?
Wherever you view the eclipse, eye safety must be your biggest concern. Looking at the sun unfiltered, even for an instant, can cause permanent eye damage or blindness. Never view the sun or partial eclipse phases with the naked eye, sunglasses, neutral density glass, double thickness of darkened film, smoked glass or other homemade filters.
You can find safe solar filters and eclipse glasses at suppliers listed here: eclipsewise.com/extra/equipment.html#Solar_Filters. Be sure to order them immediately, since supplies may be dwindling!
To use a solar filter with a telescope or binoculars, always make sure a large enough filter is fixed solidly in front of the optics, not behind them.
If you'll lie in the path of totality, keep in mind that you'll only need filters during the partial phases and you must remove all filters during totality, or you'll miss it.
You can view the partial phases indirectly as well by making a pinhole projector. Punch a pinhole in a piece of aluminum foil and use it to project an image of the sun onto a shaded sheet of paper a few inches or a foot away. The projected image will be tiny but perfectly safe to view without filters.
Another trick is to punch out a 1/4-inch hole in a piece of paper and tape the paper over a flat pocket mirror. Position the mirror to reflect the sun's image onto a distant flat surface, preferably inside a darkened room. Modeling clay can be used to hold the mirror steady. Be careful not to shine it into someone's eyes by accident.
Of course, my favorite option is to check with your local planetarium, science museum or amateur astronomy club about where they'll be set up that day for free public viewing through properly filtered telescopes and binoculars.
To learn more, check out these popular websites: mreclipse.com/MrEclipse.html#Sun, eclipse2017.org, eclipse2017.nasa.gov, greatamericaneclipse.com and eclipsewise.com/solar/SEnews/TSE2017/TSE2017.html.
Wherever you'll be on E-Day, be sure to enjoy the sky show and all the events surrounding it. The next solar eclipse visible throughout North America won't come until 2023.
Next week, I'll conclude my four-part series with some tips on eclipse photography. Anyone with a camera will want to check that out.
Visit Dennis Mammana at www.dennismammana.com. To read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.