Witnessing scientific history during the Great American Eclipse on Monday, Aug. 21

Outside of astronomy, an eclipse is defined as a loss of significance in relation to another thing. Ironically, the Great American Eclipse that will occur on Monday, Aug. 21, will find great significance in scientific history.

A total solar eclipse occurs when the moon passes between Earth and the Sun, temporarily obscuring the Sun’s prominence with a shadow.

The darkest part of the moon’s shadow, known as the umbra, will form the path of totality as it sweeps across 12 states. Only observers in that 70-mile path will experience a total solar eclipse.

Everyone in the United States, save the northeastern corner of Maine, will experience at least a 50 percent partial eclipse.

The total eclipse will make landfall in Oregon at 10:15 a.m. PST, and leave South Carolina for the Atlantic at 2:49 p.m. EST.

The National Aeronautics and Space Administration interactive eclipse map reports that the start of the partial eclipse in Ritzville will be at 9:11 a.m., building to a maximum of a 93 percent obscuration (by comparison, a total eclipse is 100 percent obscuration) at 10:25 a.m.

The end of the partial eclipse for Ritzville will occur at 11:45 a.m.

Those in the path of totality will witness the full effect of the eclipse.

Kristen Thompson, assistant professor of physics at Davidson College, explained, “You’ll see this shadow racing towards you… It can be described as almost a black curtain that is rising up out of the Earth and just shielding you in darkness.”

However, the conditions of a full eclipse, including complete darkness and complete observations of the Sun’s atmosphere, are only observable from the path of totality.

“The sky will certainly appear very strange under

conditions,” explains Jay Ryan on American Eclipse USA’s website, adding, “But the Sun is not extinguished at anything less than 100 percent obscuration.”

Ryan reported, “Even at 99 percent obscuration, the Sun is still 10,000 times brighter than it would be during totality!”

It is important to note that protective eclipse viewing glasses, cameras, binoculars, or welder goggles are necessary to prevent eye damage while viewing a partial eclipse, as well as a total eclipse before and after it reaches 100 percent obscurity.

Regardless of whether or not viewing within the path of totality is possible, witnessing the event in any capacity will be taking part in scientific history.

Noting the rarity of the event, Thompson said, “This will be the first total solar eclipse to pass through the United States since 1979.”

“What’s even more remarkable,” she added, “is it’s been 99 years since a total solar eclipse has passed coast to coast through our country, from the Pacific to the Atlantic.”

Further, the Great American Eclipse is named for the fact that it will only occur on American soil. The last time a total eclipse had this distinction was in 1257.

Although witnesses in South America will be able to watch a total solar eclipse in July of 2019, those interested in an exclusively American total solar eclipse will have to wait until 2316.

The rarity of the total solar eclipse is due to the specific requirements that must be present.

There must be a new moon near a lunar node, points where the orbital planes of Moon-to-Earth and Earth-to-Sun intersect. Additionally, the Moon, Earth, and Sun must be aligned in a straight line, and the Moon must be near its lunar perigee (its closest point in orbit to Earth).

Based on these conditions, it was astrophysicist Neil Degrasse Tyson who said, “I look up at the sky and I know that we are part of this universe, we are in this universe, but perhaps more important than both of those facts is that the universe is in us.”

His words are especially true during historical celestial events.

Community members have the opportunity to witness scientific history and grow closer to the universe with the coming of the Great American Eclipse on Monday, Aug. 21.