- The Total Solar Eclipse Its Path Across the United States Since 1918
- On August 21, 2017, a total solar eclipse was visible across the entire contiguous United States since June 8, 1918.
The path of totality touched 14 states, although a partial eclipse was visible in all 50 states. The area of the path of totality was about 16% of the area of the United States.
The event's shadow began to cover land on the Oregon coast as a partial eclipse at 4:06 p.m. UTC (9:06 a.m. PDT), and its land coverage ended as a partial eclipse along the South Carolina coast at about 6:44 p.m. UTC (2:44 p.m. EDT). Visibility as a partial eclipse in Honolulu, Hawaii began with sunrise at 4:20 p.m. UTC (6:20 a.m. HST) and ended by 5:25 p.m. UTC (7:25 a.m. HST).
Future total solar eclipses will cross the United States in April 2024 (12 states) and August 2045 (10 states).
Scientists have been very excited about this eclipse.
Total solar eclipses are marvelous opportunities to study Earth’s intimate relationship with the sun.
Eclipses happen about once every 18 months. But because Earth’s surface is covered mostly by water, they tend to occur over remote locations that are difficult for scientists to reach with advanced equipment for observation. For most American scientists it is perhaps the most accessible total solar eclipse since the last one to touch the lower 48 states in 1979. And in those 38 years, their equipment and ability to study the phenomena have greatly improved.
Scientists have long been puzzled by the sun’s corona, the thin plasma veil that encases the star, because it burns more than a million degrees hotter than the sun’s surface. Only during totality is the corona visible from Earth.
That’s when astronomers and citizen scientists across the total eclipse’s 3,000-mile long path will focus their attention on the white, wispy crown. They will observe it with telescopes, some as a part of the Citizen CATE project which aims to film totality for 90 minutes across the country. A few scientists will even be collecting images of the corona from airplanes soaring about 45,000 feet in the air.
Another headliner is Earth’s ionosphere, the electrically charged layer of the upper atmosphere through which communication and navigation signals move. Scientists will use radio waves from ham radios, GPS sensors and giant radars to investigate how this layer is affected by the sudden darkening caused by the eclipse.
- source : New York Times