Peninsula plans for solar eclipse

savwilliams@tidewaterreview.com

In less than a week, the sun and moon will work in a spectacular tandem that graces the area only once every several hundred years – but whatever you do, don't look.

Not without eye protection, that is.

The Aug. 21 total solar eclipse is set to pass diagonally through the United States, starting in Oregon and finishing in South Carolina. Viewers in James City and York counties will only be able to see a partial eclipse from this vantage point, but local organizations and residents are gearing up to watch the moon cover about 85 percent of the sun next week.

In this area, the moon will start to overtake the sun at 1:20 p.m., will reach its maximum coverage at 2:46 p.m., and will have finished its display by 4:05 p.m.

Chris Benner, a research professor emeritus at the College of William and Mary who got his bachelor's in astronomy and his doctorate in planetary sciences, packed to go view the eclipse in western Nebraska, in its path of totality. He said in that area, the eclipse will occur in the morning, and most storms there form in the afternoon, giving him good chances of an unobstructed view.

Because the moon follows an elliptical orbit, Benner said, its distance from the Earth can vary slightly. The difference in its size from our vantage point affects the size, or width, of the eclipse's shadow. Next week the moon will be closer to the Earth, so the eclipse's path will carve out a 70-mile-wide swath of the country — wider than usual, Benner said.

Benner said the last near-total eclipse that would have been visible from the Peninsula happened in 1984. In that instance, the moon was a distance from the Earth that brought it up to the verge of a possible total eclipse — but after Benner painstakingly prepared to conduct eclipse-related experiments in a Barhamsville farmer's backyard, a rainstorm rolled in and obscured the team's view of the event. Without visual data, Benner remains unsure of whether that occurrence qualified as a total solar eclipse.

According to NASA, the last total solar eclipse to cut through the United States happened in 1918.

One benefit of a total eclipse is that in the minutes where the moon completely blocks the sun, scientists and onlookers are treated to an uninhibited view of the sun's corona. The corona is the outer part of the sun that appears to form rays or loops. While the portion of the sun's gas that scientists refer to as the "surface" of the star is about 5,500 degrees Celsius, the corona is in the millions of degrees, Benner said. He said the corona is about 1 million times dimmer than the brightness of the sun's surface. Other than that, scientists don't know much about it.

"To this day, we don't know for sure why the corona is that warm. It's very strongly been suspected for a very long time, and almost certainly is correct, it has something to do with magnetic fields," Benner said. "The problem is you can't observe it, because you've got the sun sitting right next to it. Traditionally, the only way to view the corona is during a total solar eclipse. And the corona looks different in every eclipse."

Benner said amateur photographers are teaming up across the path of totality this month to photograph the corona over the course of several hours, as its viewing window shifts with the sun and moon, to learn about how quickly the rays stretch, bend or move.

"We don't have any idea how fast it changes," Benner said.

Viewers won't be able to see the sun's corona unless they travel to the eclipse's path of totality, the nearest part of which is in South Carolina, where on Aug. 15, Airbnb reported only 3 percent of the state's listings are still available for the night of Aug. 20.

Peninsula residents avoiding these historic crowds will still be treated to a spectacle. Some of the area's libraries and parks will be hosting eclipse parties, and on Tuesday, many organizers said there is still room to sign up and participate in events.

There are different ways to measure how much of the sun the moon will block.

"Magnitude is the convenient thing for astronomers to talk about," Benner said. "If you take the diameter of the sun, a line going through the center, it's how much of that diameter will be covered at maximum eclipse. But what you're really more interested in is what's called the obscuration — what fraction of the sun is covered. Because everything's round, circles and so forth, the two numbers are somewhat different."

An interactive map created by NASA provides both the magnitude and obscuration of the eclipse for any location in the United States, along with the time the eclipse will begin, peak and end at a viewer's exact coordinates. In Williamsburg, the moon's obscuration will reach about 85 percent and will peak around 2:45 p.m.

However, that's not all a person needs to know in order to watch the eclipse.

Looking directly at the sun without adequate eye protection is dangerous, except for the brief period of totality in the path of locations exactly opposite the moon from the sun. In eastern Virginia, there won't be a time on Aug. 21 that people can safely view the eclipse without solar glasses — and no, regular sunglasses won't cut it.

"It's the surface brightness of the sun that damages your eyes," Benner said. "If you take out 85 percent of the sun, the rest of it is just as bright on your eye and can do just as much damage as if you look at it without an eclipse. It's just, a smaller chunk of your eye is going to get fried."

NASA is urging particular caution in procuring solar glasses and viewing filters. According to NASA's website, counterfeiters are taking advantage of the eclipse glasses rush, and it's no longer sufficient to go on faith that every product touting the International Organization for Standardization (ISO) safety certification is genuine. Even if glasses appear to work by blocking out most visible light, counterfeit glasses do not protect a viewer from the sun's damaging ultraviolet and infrared radiation.

York River State Park, the James City County Library and the Tabb Library are hosting eclipse viewing parties where they will pass out safe glasses to participants. Williamsburg Eye Care on Bulifants Boulevard is also doling out free solar glasses starting Thursday, until they run out.

Williams can be reached by phone at 804-824-8289.

Experience the eclipse

Williamsburg Eye Care

Event: Solar glasses giveaway, limit 2 per family.

Time: 9 a.m. to 7 p.m. Thursday; 9 a.m. to 5 p.m. Friday.

Date: Aug. 17-18

Location: 101 Bulifants Blvd. Suite A, Williamsburg

Cost: free

York River State Park

Event: Eclipse viewing party with an eclipse-themed craft and a limited number off free solar glasses.

Time: 1:30-3:30 p.m.

Date: Aug. 21

Location: 9801 York River Park Rd., Williamsburg

Cost: $4 per car

James City County Library

Event: Eclipse viewing party with crafts and solar glasses for the first 50 children.

Time: 1 p.m.

Date: Aug. 21

Location: 7770 Croaker Rd., Williamsburg

Cost: free

Tabb Library

Event: Eclipse viewing party with a limited number of free solar glasses, a live-stream video of the eclipse, snacks and a sun-themed craft.

Time: 2-3 p.m.

Date: Aug. 21

Location: 100 Long Green Blvd., Yorktown

Cost: free

Jamestown Settlement

Event: Eclipse demonstration with historical narrative of the impact of celestial bodies on navigation. Learn to make eclipse projectors out of two cards and a thumbtack. *Do not look directly at the sun without proper eclipse viewing equipment.

Time: 2:30 p.m.

Date: Aug. 21

Location: 2110 Jamestown Rd., Williamsburg

Cost: $17 per adult. Free with proof of residency for James City County, York County and Williamsburg residents and College of William and Mary students.

American Revolution Museum

Event: Eclipse demonstration with historical narrative of the impact of celestial bodies on navigation. Learn to make eclipse projectors out of two cards and a thumbtack. *Do not look directly at the sun without proper eclipse viewing equipment.

Time: 2:30 p.m.

Date: Aug. 21

Location: 200 Water St., Yorktown

Cost: $12 per adult. Free with proof of residency for James City County, York County and Williamsburg residents and College of William and Mary students.

Online tools and information

NASA's interactive map

eclipse2017.nasa.gov/sites/default/files/interactive_map/index.html

Where to find ISO certified eclipse equipment

eclipse.aas.org/resources/solar-filters

ISO certified eclipse glasses

tse17.com/eclipse-shop/

explorescientificusa.com/search?type=product&q=eclipse

Are your pre-purchased eclipse glasses authentic?

eclipse.aas.org/eye-safety/iso-certification

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