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There's a penumbral lunar eclipse in about three weeks. That's two weeks before the total solar eclipse. Both of these eclipses have favorable times and geometries for observers in North American longitudes.

There's an unsung property of lunar eclipses that's especially worth remembering for a penumbral eclipse,which otherwise is mostly a non-event: The Moon is brightest in terms of surface brightness (magnitudes per square minute of arc) just as it's entering the penumbra due to the "opposition surge" which makes the Moon much brighter when its angle from the Sun is very close to 180°, meaning just outside the Earth's shadow for us terrestrial observers. The overall or total brightness of the Moon this time around will be less than the maximum possible since this Full Moon is smaller than average in apparent diameter. March 25 is near apogee which makes the Moon small on that date but guarantees a big Moon for excellent solar eclipse geometry at perigee two weeks later on April 8). Nonetheless the "glow" of the Moon's face --that's surface brightness-- is dazzling just as the Moon enters the penumbra. And this is noticeably brighter than "average" Full Moons when the Moon misses the shadow by up to five degrees.

I started looking at this a couple of years ago and thought I might be onto something that had never made it into print, at least in popular articles, but of course the prolific author and computer of all things astronomical, Jean Meeus, wrote about it a quarter century ago in his book "More Mathematical Astronomy Morsels". And yet it's still not widely enough known. The Moon is a brilliant beacon just as it enters the penumbra.

Frank Reed
Clockwork Mapping / ReedNavigation.com
Conanicut Island USA