Total solar eclipse completes trek across Mexico, United States, eastern Canada

April 8 (UPI) -- A rare total solar eclipse, the first in seven years and the last in two decades over the continental United States, completed its trek Monday across parts of Mexico, 15 states and eastern Canada.

Tens of millions of people watched throughout the day as the moon blocked-out the sun's light and warmth, plunging parts of the country into temporary darkness. A total eclipse can cause as much as a nine-degree drop in temperature, eliciting reactions from plants and animals.

Spectators in Matzatlan, on Mexico's Pacific Coast, were the first to view Monday's total eclipse. Those along the Atlantic coast of Newfoundland, Canada were the last to view totality before the arc of the eclipse moved out to sea.

At the start of the day, the path of totality crept from Mexico through Texas before continuing northeastward.

Fredericksburg, Texas, experienced more than four minutes of total darkness as a crowd, gathered at an outdoor stage, shouted and cheered. Planetary Society chief executive officer Bill Nye, who hosted the event, called it "magical."

"I am just so happy to be sharing this with you all," Nye shouted.

Michigan, Arkansas, Oklahoma, Ohio, Pennsylvania, Vermont, New York, New Hampshire, Ohio, Missouri, Indianapolis, Kentucky, Texas, Maine and Illinois all saw a swath of their states plunged into darkness Monday.

The eclipse began before 1 p.m. local time in Missouri with its duration lasting until after 3:15 p.m.

The University of Arkansas was full of spectators excited for the impending spectacle, as well.

Residents in Kentucky prepped with their own spectacles just as in western Pennsylvania near Erie and the Cleveland, Ohio, areas. In Maine, the total solar eclipse started at around 3:28 p.m. local time.

"This might be the most-watched solar eclipse ever," Michelle Nichols, director of public observing at the Adler Planetarium, told NBC Chicago.

Thousands also gathered to watch the eclipse at the only NASA facility inside the path of totality, at the NASA Glenn Research Center in Cleveland, where certified eclipse glasses or solar viewers were encouraged or provided.

"Total(ly) stunning. Breathtaking views of the total solar eclipse as seen from Cleveland," NASA's Glenn Research Center wrote Monday in a post on X.

The total eclipse began as the sun rose and eventually became visible over the Pacific Ocean. It was first visible in the continental United States in Bell County, Texas, at 1:27 p.m. CDT, and culminated in Maine at 3:35 p.m. EDT.

Not everyone in the path of the full eclipse witnessed the event equally. Earlier in the day in Texas, organizers of a Burnet County eclipse festival were forced to cancel their gathering because of severe weather.

San Antonio, Austin and Dallas were some of the biggest cities in Texas that were in the path of the total eclipse. Little Rock, Indianapolis, Cleveland and Buffalo were also well-positioned to see the rare astronomical event.

People living along the path of the total solar eclipse were able to view the cosmic event for two to four minutes with the use of protective eyewear.

Anyone experiencing vision problems or discomfort after viewing Monday's eclipse were encouraged to see an eye doctor, according to Ronald Benner, an optometrist and president of the American Optometric Association.

"For most people, it's an alteration of color vision," Benner said. "The next morning, colors just don't look right, or it may be bleached out or just kind of hazy all the time. For others, it may be that they actually have holes in their vision."

While the path of totality was limited, millions of others throughout the United States were able to see a partial solar eclipse, depending on local weather conditions.

Texas has not seen a total solar eclipse for 146 years, which recently promoted authorities to declare a state of emergency in some areas ahead of an expected massive influx of tourists. State officials in Bell County, Texas, prepared for a surge of onlookers along a 480-mile stretch of road directly in the path of the total solar eclipse.

Montreal was the biggest Canadian city in the path of the total eclipse. The Canadian city of Gander in Newfoundland and Labrador were the last major hubs to see the moon pass between Earth and the sun.

Other cities, such as Cleveland, hosted viewing parties, while Major League Baseball pushed back the start times for several Monday games because of the eclipse.

For those who were not able to travel to see the eclipse in person, NASA live-streamed the event. The three-hour program showcased the eclipse from several different locations.

Astronauts aboard the International Space Station presented science experiments related to the eclipse during the NASA live stream.

In another science-related move, NASA followed the entirety of the eclipse path using jets, while collecting data on the sun and Earth's atmosphere. The space administration affixed spectrometers and other instruments to its WB-57 twin-engined reconnaissance aircraft to help make observations of the sun's corona and Earth's atmosphere. The planes first entered service with the U.S. Air Force in 1953 and are part of NASA's high-altitude research program.

Monday's eclipse "provides scientists a unique opportunity to study this mysterious region of the sun," NASA said in a recent blog post.

Those who did not see the NASA live feed or watch the eclipse in person will have to wait decades until the next path of totality re-appears over the continental United States.

A pair of total solar eclipses will appear in 2044 and 2045.

The 2044 total eclipse will be visible in North Dakota, South Dakota and Montana, while parts of the Canadian provinces of British Columbia, Alberta and Saskatchewan will also be in the path of totality.

The most recent total eclipse took place on Aug. 21, 2017. People in Oregon were the first to see the partial eclipse, which began around 9:04 a.m. PDT. The full eclipse became visible 72 minutes later and lasted for a full minute.

At the outset in Oregon, people in Portland sat in silence before bursting into applause as the darkest period began, eventually igniting fireworks and sending them spiraling into the temporarily darkened sky.

People in Carbondale, Ill., home to Southern Illinois University, were subject to the longest extended period of total darkness with 2 minutes and 38 seconds. The university's Saluki Stadium was packed to its 15,000-person capacity for a viewing party and related pre-eclipse festivities. Weather did not cooperate that day, with heavy low cloud cover obstructing all but five seconds of the total solar eclipse.

Crowds also packed sold-out stadiums in St. Louis, Nashville and Charleston, S.C., to watch the event. Dozens of U.S. Army Reserve members watched it from a military cargo plane.

The full eclipse lasted for just over 1 minute and 40 seconds in South Carolina, the last state able to see it.