On Oct. 14, 2023, an annular solar eclipse will occur across the Americas during which a part of the moon’s shadow will travel faster than 5,500 mph, greater than twice as fast as a bolt of lightning. It can also travel as slow as 1,250 mph, in regards to the same as a jet fighter.
All of it is determined by where on Earth the eclipse is occurring. “How briskly the eclipse travels is determined by the geometry — where on Earth the shadow is traveling, in addition to the distance to the moon and the moon’s orbital speed,” Dan McGlaun, an eclipse calculator and cartographer whose website Eclipse2024.org simulates exactly what observers will see through the annular solar eclipse, told Space.com.
Where the eclipse will move fastest
The incontrovertible fact that Earth is round makes an enormous difference to the speed of the eclipse. Because it first strikes the northern Pacific Ocean the moon’s antumbral shadow (inside which the “ring of fireside” will probably be visible) will move at an astonishing 198,842 mph, based on Xavier Jubier’s interactive eclipse map. Because it departs the planet 219 minutes later within the Atlantic Ocean it should accomplish that at 582,976 mph. “The shadow at all times moves fastest on the extremes of the trail, because at those locations, the axis of the shadow is more tangent to Earth’s surface,” said McGlaun.
Where the eclipse will move slowest
In the course of the trail — where a “ring of fireside” will appear for five minutes 17 seconds off the coast of Nicaragua — the eclipse will travel at a relative snail’s pace of just 1,251 mph. “In the course of the trail, the axis is essentially perpendicular to the surface,” said McGlaun. “So although the moon itself doesn’t slow, the intersection of the Earth and moon’s shadow does.”
How briskly the eclipse will move within the U.S.?
Nowhere within the U.S. will the shadow’s speed be at its fastest or slowest for this eclipse. Because it strikes the Oregon coast at 9:13 a.m. PDT the speed of the moon’s shadow may have already slowed down significantly to five,683 mph. Because it leaves the coast of Texas just 50 minutes later at 12:03 p.m. CDT it should have slowed right down to 1,772 mph. So during its passage southeast across the U.S., it should decrease in speed by 3,911 mph.
The moon’s shadows explained
When the moon is closest to Earth it may well completely cover the sun to create a complete solar eclipse. For the reason that moon is way smaller than the Earth it casts a tiny shadow across the Earth’s surface — the trail of totality — but that is not what’s happening on October 14. On that day it should be a bit farther away in its orbit so it won’t completely cover the sun. Nonetheless, as seen from a 125-mile wide path through eight U.S. states, it should go straight across its center to create a temporary “ring of fireside”.
The moon’s central shadow, its umbra, is cone-shaped. During a complete solar eclipse, the tip of that cone touches Earth. Nonetheless, during an annular solar eclipse that cone doesn’t quite touch the Earth in any respect. This creates an antumbra where the moon appears completely throughout the sun’s disk, based on GreatAmercianEclipse.com.