Facts about the US solar eclipse on August 21
On Monday, August 21, 2017 for the first time in 99 years, a total solar eclipse will march across the entire United States. The Great American Eclipse” will cast a shadow over the whole country, moving diagonally from Oregon in the northwest to South Carolina in the southeast.
Here are some facts on this eclipse, and what makes it so unique:
- This is the first eclipse to pass over the United States in the 21st century.
- It is the first total eclipse on American soil since 1991, when one was visible from the Big Island of Hawaii.
- Having a total solar eclipse move across entire the United States is quite rare and last time it happened was in 1918.
- Solar eclipses occur when the Moon moves between the Earth and the Sun, blocking light from the Sun.
- Total solar eclipses happen because the Sun’s diameter is 400 times wider than the Moon’s, but it is also 400 times farther away.
- When the two line up just right, the Moon obscures the entire Sun, and the skies go dark.
- These total eclipses happen every 12 to 18 months somewhere in the world, often over the open ocean since most of the Earth is covered by water.
- Unless it’s cloudy, Lincoln Beach, Oregon, will be the first location in the continental US to see the eclipse, beginning at 9:05 am (1605 GMT), according to NASA.
- The path of totality spans about 70 miles (113 kilometers) and will pass through 14 states. Parts of 14 American States Will Go Dark.
- “Its longest duration will be near Carbondale, Illinois, where the Sun will be completely covered for two minutes and 40 seconds,” says the US space agency.
- The total eclipse ends at 2:48 pm (1848 GMT) near Charleston, South Carolina.
- The entire eclipse will take a total of four hours, four minutes to make its way across the nation.
- Hundreds of millions of people will fall under the shadow of the eclipse, since the whole country will be darkened — some parts more than others.
- Researchers say the eclipse is important because it will enable astronomers to study the outer realm of the Sun, known as the corona.