People who look skyward in the Portland area on Monday at 2:45 p.m. will be able to see more than half the sun blocked out by the moon – if the sky is clear and they have approved glasses.

It’s expected to be the most-watched solar eclipse in human history, but for residents who haven’t scored a set of special eclipse glasses yet, it may be too late. Many retailers are sold out and questions are being raised about counterfeit glasses that don’t offer proper protection from the sun’s rays.

“We have a lot of people asking us for eclipse glasses, but they are very hard to procure for love or money,” Edward Gleason, the manager of the Southworth Planetarium at the University of Southern Maine, said on Monday. “We had 1,000, and when we tried to restock them, our supplier laughed at us.”

But the planetarium is offering options. It plans to set up a telescope outdoors for viewing and is hosting a live feed from NASA inside starting at 1:45 p.m., for those who call to make reservations.

Other viewing parties are being organized in Monument Square by the Portland Public Library and in Freeport at L.L. Bean.

As for the weather, forecasting a week out can be tricky, but the National Weather Service in Gray expects conditions to improve after some rain Sunday.

A solar eclipse occurs when the moon passes between Earth and the sun. Viewed from Earth, the image of the sun is totally or partially blocked, depending on where you are during that period.

Monday’s total solar eclipse will be visible in totality within a 70-mile wide band across the entire contiguous United States. The last time that happened was 1918.

The path of totality will pass through 14 states, starting in Oregon and ending in South Carolina. North and south of that narrow corridor, anywhere from 20 to 99 percent of the sun will be covered by the moon.

Gleason said the planetarium has been getting calls from people who have seen or read the flood of national media stories about the eclipse, and wonder if they can see a total eclipse in Maine. The answer is no. Maine will experience a partial eclipse.

In Boston, 63 percent of the sun will be blocked. Coverage will fall off to 58 percent in Portland and 49 percent in Presque Isle. In Portland, the eclipse will start at 1:29 p.m., peak at 2:45 p.m. and end at 3:57 p.m.

DEARTH OF GLASSES

It’s unsafe to view a partial eclipse without the proper eyewear, because the intense ultraviolet and infrared rays can damage the eyes. Sunglasses, X-ray film and various other filters don’t do the job. Safe eclipse-viewing glasses must meet international certification standards, according to the American Astronomical Society.

The group has a list of reputable vendors on its website.

The unprecedented demand for eclipse glasses apparently has led some sellers to offer glasses, especially over the internet, that don’t meet industry standards and aren’t known to be safe. In recent days, Amazon has announced it will offer refunds to customers who bought suspect glasses from its website.

Some stores have been identified as selling approved glasses, including Walmart and Lowe’s Home Improvement. But there’s no easy way to know if they’re locally available, based on interviews Monday with managers.

The Walmart Supercenter in Scarborough said it didn’t have them in the store, only online. Lowe’s in Scarborough said they were sold out. The Sanford Lowe’s was shipping the ones they had to another store.

One way to have the right glasses is to attend a sanctioned viewing event.

The Portland library will give away glasses at its Monument Square event, according to its website. A similar event is planned for the back lawn of the Auburn Public Library.

At Bean, the event will be led by Ron Thompson, director of Southern Maine Astronomers. A telescope will project the image on a screen, to make it easier for a large crowd to witness. Looking at the stars is a popular activity when people are camping or away from city lights, Bean spokesman Eric Smith said, and the company often hosts night sky viewing parties when there is a big astronomical event.

“This is just one of those big astronomical events that happens during the day, with our own closest star,” Smith said.

All the planning and anticipation will be futile if its a rainy or cloudy day. But Andy Pohl, a meteorologist at the Gray office, said his review of the next week’s weather patterns indicates a system moving offshore Sunday and being replaced by high pressure on Monday. It’s too early to know, he said, if the system will move as quickly as expected. If it does, Pohl said he’s forecasting a 20 percent cloud cover with clearing as the day goes on.

Personally, Pohl isn’t going to be at the whims of Maine weather. He grew up in Nebraska and is heading home to watch the total eclipse, in a part of the country where clear skies are common on a summer afternoon.

Whatever the weather, Gleason said publicity about the eclipse has value. It makes people curious about science and the natural world, and reminds us that we are all floating in a void, out in the universe.

And if things don’t go well for Monday’s partial eclipse, Gleason is buoyed by the knowledge that Maine will be in the path of totality for an upcoming solar eclipse, April 8, 2024.

“As funny as it may sound, we’ll start preparing in a couple of years,” he said. “And we’re going to be stockpiling glasses.”

Tux Turkel can be contacted at 791-6462 or

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