April Solar Eclipse

iss_eclipse
Time lapse exposure of space station in silhouette against the Sun as seen from Earth on August 16, 2003
Credit: Roland Stalder

Solar eclipses are grand cosmic events that no nature-watcher wants to miss — and an opportunity to see one will occur for most of the southern United States on Friday afternoon, April 8th.

This will be only a partial eclipse, which is not nearly as spectacular as a total one. The Sun will never be completely blacked out by the Moon crossing in front of it, and daylight in the U.S. will not dim noticeably. But the eclipse will still provide a fine celestial spectacle — for those who know how to watch it safely.

The farther southeast you are, the deeper the eclipse will be. Along a line from Philadelphia to San Diego, only a slight, barely perceptible dent will appear in the Sun’s left edge. But from South Carolina through Texas, the Moon will take a substantial bite out of the Sun. The eclipse will be total along a thin line crossing the South Pacific and annular (a ring of bright Sun completely encircling the dark silhouette of the Moon) along a line crossing parts of Costa Rica, Panama, Colombia, and Venezuela.

SOHO_SUN_ART
Spectacular science from the solar observatory, or SOHO.
Credit:SOHO

The eclipse will also be partial across all of Central America and much of South America.

The partial eclipse will last anywhere from just a few minutes to more than an hour, depending on your location. You’ll need to know when it begins, when it reaches maximum, and when it ends at your site. SKY & TELESCOPE has computed a timetable for many cities and towns across North America. It is available as a PDF file, which you can download from the online version of this press release (see link below) and open on any computer using the free Adobe Reader software.

During a partial or annular eclipse, some of the bright Sun always remains in view. Warning: You should never look at the Sun (partially eclipsed or not) without proper eye protection! Examples are special "eclipse glasses" properly designed for the purpose, a #14 rectangular arc-welder’s filter, or special astronomers’ solar filters. Staring at the bright Sun can burn your retina, leaving a permanent blind spot in the center of your vision. The only reason a partial eclipse poses a special danger is because it can prompt people to look directly at the Sun, something they wouldn’t normally do.


Related Web Pages

SOHO15 : Coronal Heating Workshop
Solar and Heliospheric Observatory
TRACE
Solar and Magnetospheric Theory Group, St. Andrews
Surviving Halloween Solar Scare
Our Typical Dwarf Star