Solar eclipse sights might vary on the edge of totality: report

a solar eclipse with a bit of sun peeking through the edge of the moon's shadow
The Baily's Beads effect as seen from Madras, Oregon, during the Aug. 21, 2017, total solar eclipse. (Image credit: NASA/Aubrey Gemignani)

If you plan to watch the solar eclipse April 8 at the edge of the totality path, you might want to move further into the shadow.

New amateur calculations of the solar eclipse path suggest that variations in the local terrain might change if you see a total eclipse, or how long the eclipse is experienced, compared to older estimates. The work, first reported in Forbes, is not peer-reviewed, however. So take the findings with a dose of caution.

The next solar eclipse will happen in parts of the United States, Mexico and Canada. An eclipse of the sun happens when the moon passes in front of our solar neighbor. Because the moon is so small, its shadow is narrow indeed and that means totality may only last a few seconds, or minutes, in a tiny part of the Earth's surface.

Related: April 8 total solar eclipse could bring uptick in fatal car crashes, scientists caution

Amateur John Irwin, on the Besselian Elements website, re-examined the eclipse path with "adjustments that account for the topographic elevation, both around the limb of the moon and on the surface of the Earth." 

While you can click on the embedded map to see the details, Forbes identified 15 areas that may see some differences of the eclipse totality path.

On their Facebook page, the Besselian team describes themselves as "a team of dedicated amateur astronomers, passionate about solar eclipses", which means their work hasn't been fact-checked by scientists as you'll see in areas like professional journal publications.

EarthSky, another astronomy publication, asked C. Alex Young, associate director for Science in the heliophysics science division of NASA Goddard Spaceflight Center, about the new findings

Young didn't explicitly endorse Besselian's work, but said he will have a peer-reviewed paper coming out shortly showing the sun is slightly larger than expected. He told EarthSky that finding was uncovered during a previous U.S. total solar eclipse in 2017. That work, he added, may influence future eclipse mappings.

If you're looking for a takeaway solution, the best idea is to move as far into the region of shadow as you can to avoid any hiccups. And when you're observing the solar eclipse, make sure you have the right tools to do so. 

Our guide on how to observe the sun safely guide tells you what you need to know to look at the sun. We also have a guide to solar eclipse glasses, and how to safely photograph the sun if you'd like to get practicing before the big day.

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Elizabeth Howell
Staff Writer, Spaceflight

Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 specializing in Canadian space news. She was contributing writer for Space.com for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, "Why Am I Taller?" (ECW Press, 2022) is co-written with astronaut Dave Williams. 

  • bolide
    "variations in the local terrain might change if you see a total eclipse, or how long the eclipse is experienced"

    Sorry, but this is gibberish. If you guys can't afford to employ an editor, maybe you could at least have the writers check on each other's work?
    Reply
  • billslugg
    "variations in the local terrain might change if you see a total eclipse..."

    The calculations for where the edge of the eclipse is assume a billard ball shaped Earth. Your elevation above or below that mean sphere alters the location of that line. A few thousand feet of elevation might shift the line a few hundred feet. Also, mountains on the Moon move the terminator according to how high they are. The line can defy prediction by hundreds or thousands of feet.
    Reply
  • Helio
    I'd bet the umbral shadow is actually off by more than 10 miles, if you count the height of cloud cover. ;)
    Reply
  • Classical Motion
    I was gona hang a pin hole sheet on the back porch. But they say it's gona be cloudy here in Roanoke. So no sheet hanging. I have experience tree shade before, but my tree hasn't leafed yet. But I have a pine tree. If it clears a bit, I want to see what a pine leaf eclipse looks like.

    We have a hex on us. We have plenty of sunshine but when a skyward event occurs.....we get clouds, day or night. Worse place in the world for a star/sun gazer. Haven't seen anything up there since 2001.
    Reply
  • billslugg
    I feel yolur pain Bro. I lived near Scranton, PA for 8 years back in the 70's. We were under the jet stream, a few hundred miles east of the Great Lakes, on a 1,000 foot elevation rise. We could easily go two weeks without a speck of blue sky. Comet West came and went without one single clear night.
    Reply
  • bolide
    Helio said:
    I'd bet the umbral shadow is actually off by more than 10 miles, if you count the height of cloud cover. ;)
    Why should the height of cloud cover have any effect?
    Reply
  • billslugg
    Helio is the Sun God, we do not question the Sun God.

    PS - note the "winky eye" next to the sentence.
    Reply
  • Helio
    bolide said:
    Why should the height of cloud cover have any effect?
    Yeah, I was just joking about the fact that there's no umbral shadow (ignoring the darkening) below the clouds, but above them.
    Reply
  • Helio
    billslugg said:
    Helio is the Sun God, we do not question the Sun God.
    Bless you my son. :p
    Reply
  • Questioner
    Eventually as the moon gets further from Earth we will never again see total Solar eclipses because the Moon's disk will be too small.

    Enjoy total Solar eclipses while they last...
    Reply