This week, the moon is in it’s last quarter, and the evening sky is dark.  I’ll still be spending some time trying to hunt down Iridium Flares, but there’s another strange light in the sky as well – zodiacal light.

Zodiacal Light from the Pantenal, European Space Observatory, 2009, Wikimedia Creative Commons

Zodiacal Light is a ghostly, pyramid-shaped white glow visible just after evening twilight ends or before morning twilight begins.  It’s most easily seen at northern latitudes, in the winter, on a dark night when the ecliptic is almost straight up.  The pyramid extends from the horizon up through the constellations of the zodiac (Taurus, Gemini…).

This glow is actually the glow of a disk of interplanetary dust, orbiting our sun along with the planets, asteroids, and everything else, and it lies in the ecliptic.  (Remember the ecliptic?  The plane where the planets orbit, aligned with the constellations of the zodiac.)

Apparently, this dust, viewed from afar, is the second brightest thing in our solar system, after the sun itself, but viewed from within, it’s not very apparent to us.  It’s there, though, another mysterious phenomenon we don’t get the chance to observe much.

On another note, have you noticed the continuum of change?  I’ve been outside researching and observing every week since the beginning of the year, and when you observe what’s going on as a series of events, rather than a few disconnected snapshots in time, you notice how the planets have moved (and with a telescope, that Venus is a shrinking crescent now, racing back between us and the sun), how Orion is now at its highest point in the sky (just after dark) where a while ago he was on his side with the belt stars vertical.  New constellations are visible in the east just about every night now, and the Great Bear is now standing on his tail, getting ready to emerge from winter hibernation.

Spring is almost here, and the stars are telling us about it.

So are the buds on the willow trees, but that’s a different topic.

Get Out There!

Troy

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