At the North Carolina Science Trail, we are constantly looking for fun ways to help you find science education across the state. This week Ken Brandt at the Robeson Planetarium reached out to me about an eclipse theme, as this will be a big year for eclipses in our part of the world. Of course, I jumped at the chance to share eclipse education with all of you! Please join us each week for a new Eclipse Blog with lessons for how you can experience the partial eclipses coming our way.
Eclipse Blog by Ken Brandt, Robeson Planetarium and Science Center, Lumberton, NC
Back in school, somewhere, you were taught about Solar and Lunar eclipses. You were also taught about the phases of the moon. Hopefully, you were taught that eclipses dealt with shadows, and phases were determined by the apparent angle between the Earth, Moon, and Sun.
But angles are also crucial in the examination of eclipse geometry. In order for eclipses to happen, a precise alignment of Earth, Moon, and Sun must exist. The apparent angle between the earth, Moon, and Sun in a total solar eclipse is 0 degrees.
Image credits belong to: space.rice.edu/eclipse/; reiff@rice.edu
Additionally, the Moon must be on the node of its orbit around Earth. This is the primary reason that we don’t see eclipses every month. Most of the time, the Moon’s orbital tilt (5 degrees relative to Earth’s orbital plane) means that usually, the Moon’s shadow is projected into space above or below Earth. The node is that point where the Moon’s orbital plane intersects with Earth’s.
Approximate view of how we will see the partial eclipse from much of North Carolina.
Fortunately we are treated to two partial solar eclipses in the next eight months! Saturday, October 14th features a special kind of eclipse called an annular eclipse. Next week in this recurring blog post, we break down annularity, and the geometry required for this event. The next eclipse after that is a total eclipse, occurring on Monday, April 8th. For many school districts, this is the Monday following Spring Break, so students will be in school during this eclipse.
This is a fairly rare event. Our next opportunity for a partial eclipse here in NC will be in 2042.
From an event planning perspective, a partial solar eclipse is problematic for several reasons. First, all steps in the eclipse must be observed without looking directly at the Sun, safely. Also, there can be long stretches of inactivity during the eclipse. Other activities must be planned for the interim between the occasional look at the projected eclipse, or through those eclipse glasses.
This set of Solar eclipses is an opportunity to engage more potential visitors to your venue, and I’ll stress safe preparation techniques as we get closer to carrying off these events in our respective venues.
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Ken Brandt directs the Robeson Planetarium and Science Center in Lumberton, NC. He is a volunteer in NASA’s Solar System Ambassador Program. He is also a member of the 3rd cohort of NC Space Grant Ambassadors, and an Ambassador for the Mars Society.