IN THE KNOW: Solar eclipses

A solar eclipse happens when the moon moves between the earth and the sun, thus blocking the sun’s light and casting its shadow on earth.

A partial eclipse happens when the moon does not completely cover the sun. When the moon obscures the sun’s entire surface, that is known as a total solar eclipse.

A total solar eclipse usually occurs every 18 months or so, while a partial solar eclipse occurs more frequently.

The Aug. 21 total solar eclipse will not be visible in the Philippines, but will be seen in Hawaii, the Americas (except the southern parts of South America), westernmost Europe and West Africa.  It will also be the first time for a total solar eclipse to cross the United States coast to coast since 1918.

This eclipse is celebrated as well because its path stretches over land for about an hour and 30 minutes, giving scientists an unprecedented opportunity to make scientific measurements from the ground, the National Aeronautics and Space Administration (Nasa) said in its website.

Most eclipses are visible over land for only a short time, because the earth’s surface is mostly ocean. —Inquirer Research

Sources: nasa.gov, pagasa.gov.ph, timeanddate.com, Inquirer Archives