Go look for the moon today and you won’t find it. With our only natural satellite roughly between Earth and the sun, it will be lost in the glare of our star as seen from our planet.
The new moon in September 2024 comes at 9:55 p.m. EDT on Monday, September 2, but it’s what it sets in motion that makes it special—a lunar eclipse and a solar eclipse.
Ring Of Fire
While the coming full moon, the “Harvest Moon” on September 17, will drift into the edge of Earth’s shadow in space to cause a partial solar eclipse, the following new moon on October 2 will obscure the center of the sun’s disk in as spectacular annular solar eclipse.
If the latter reminds you of what happened across North America on April 8, think again. While that was a rare total solar eclipse, this one is an annular type, better known as a “ring of fire.” Visible only in Easter Island and southern Chile and Argentina, solar eclipse glasses must be worn at all times.
Line Of Sight
The reason why solar eclipses can occur at all is because of a line-of-sight coincidence. The moon is about 400 times smaller than the sun, but the sun is about 400 times farther away. However, that’s not always true because the moon’s orbit around Earth is slightly elliptical. On October 2, the moon will be close to its monthly apogee—the farthest it gets from Earth each month—at the new moon. It will, therefore, be smaller in the sky than the sun, so it is unable to cover it completely. As it drifts in front of it, it will create a gorgeous ring eclipse, in this case, for a maximum of seven minutes and 25 seconds.
Mysterious Moai
The place to be for that will be Easter Island, also called Rapa Nui, where eclipse-hunters will hope for clear skies while touring the mysterious stone monolithic human figures called moai that date from the thirteenth century.
Eclipses happen because the moon’s orbital around Earth intercepts what astronomers call the ecliptic—the apparent path the sun takes through our daytime sky. The moon’s orbital path is slightly inclined to that ecliptic, about five degrees, so it intersects it twice monthly. These two points are called nodes. When the moon reaches one of those nodes at its new moon phase, it causes a solar eclipse. When that happens, it will also happen either two weeks before and/or after, causing a lunar eclipse.
‘Harvest Super Moon Eclipse’
First up this eclipse season is a partial lunar eclipse when, on September 17, a full “Harvest Moon”—also a supermoon—will mostly drift into the Earth’s outer penumbral shadow. At its peak, only 8.4% will enter its central shadow, the umbra. It will be no “Blood Moon,” instead creating merely a subtle shading of an otherwise bright lunar disk. It will be best viewed from the night side of the world—North America, South America, Europe and Africa—with an exact schedule for any location available from Timeanddate.
However, for eclipse-chasers, the eclipse season that today’s new moon sets up is all and only about the “ring of fire.”
Wishing you clear skies and wide eyes.
