consider the lunar eclipse. Here, totality isn’t particularly important. Nothing special happens during a lunar totality. Not a single strange phenomenon materializes. Indeed, many consider the visually optimum view to happen when the Moon is roughly 95% eclipsed, because then a single brilliant white spot of sunlight illuminates the moon’s edge while the rest of the moon is an eerie red. That may be more dramatic then when the Moon is completely red at totality.
A penumbral lunar eclipse
But sometimes the Moon doesn’t even go into Earth’s main dark shadow. The eclipse is then neither total nor even partial. Instead it has ventured into our planet’s outer, skimpy, penumbral shadow. When such a “penumbral eclipse” occurs, the full moon usually appears unchanged. You want your money back.
A partial penumbral lunar eclipse
Could an eclipse even get worse than that? Definitely. Sometimes the moon doesn’t even manage to fully penetrate our barely-there penumbral shadow. It grazes it, so that a piece of the Moon is in the ever-so-slightly-darker penumbral shadow while most of the Moon stands in full sunlight. At such times, not even the greatest astronomers who ever lived could tell an eclipse was happening. It’s visually a non-event. But surely such a strange, skimpy type of eclipse must be rare. Will we ever even get such an event in our lifetimes?
The June 5 partial penumbral lunar eclipse
Time for our amazing revelation. This year, 2020, there was just such a “partial penumbral lunar eclipse” on January 10. And this week we will have another on Friday, June 5! They had in common that the Moon never even fully got into the anemic penumbral shadow. But wait! Yet another partial penumbral lunar eclipse will happen a month from now, on July 5. And, hold on, there be still another one on November 30.
That’s right. Four partial penumbral lunar eclipses in 2020. Four! It’s simply unbelievable.
No comments:
Post a Comment