I’m back. All went well. Once the aliens were able to replicate and taste their first Chicago hotdog, their gratitude was boundless. My cohorts and I were released, and at least for now, Earth is safe.
We’re elated to be back. Turned out they had a fondness for Rebecca Black’s “Friday” song and played it incessantly through the ship’s sound system. I can’t tell you how happy IÂ am it’s Saturday.
New Moon is tomorrow, which means we’ve got about a week of dark, moonless evening skies ahead. That’s just what we’ll need to see a really cool constellation that practically hides in the shadow of Leo the Lion. It’s called Coma Berenices (Bear-en-EYE-sees) and refers to the hair (coma) of Queen Berenice II, a real queen who lived in Egypt in the 3rd century.
The constellation outline is little more than a right triangle composed of three dim stars. Instead, the real treasure here is what the ancient astronomer and mathematician Ptolemy referred to as ‘a nebulous mass’. If you look directly behind Leo’s tail star Denebola (den-EB-oh-la) from a moderately dark sky, you’ll be struck by a bunch of tiny stars, a.k.a Berenice’s curly locks.
I’ve never counted them, but a glance will show at least a dozen and maybe a few more. If you sweep eye around the cluster in a technique called averted vision instead of staring directly at them, you’re sure to come across it.
This swarm is a true star cluster and one of the biggest visible to the naked eye, measuring some five degrees or ‘half a fist’ across. One reason for its size is how close it is to Earth – a mere 288 light years. Only the Hyades in Taurus and a very spread-out cluster centered on the stars of the Big Dipper are closer.
Like other star clusters, Coma’s ‘hairy mass’ is a gravitationally bound system. All its stars are near one another and hang together as a unit in space as they orbit the center of the Milky Way galaxy. Astronomers know Berenice’s Hair as the Coma Star Cluster or Melotte 111, after the early 20th century astronomer Philibert Melotte, who compiled a catalog of open clusters.
What’s a bit odd about Mel 111 is its location. Most star clusters of its type are found in the spiral arms of the galaxy. That means you’d expect to see it against the background of the misty Milky Way that cuts across the sky on early April evenings from northwest to southeast. The Coma Star Cluster is off by itself near the galaxy’s north pole. Why is still a bit of a mystery.
Take a look the next clear night. If you already know where Leo is, you’re in great shape to find Coma. Still in the dark on Leo’s location? You can use the Big Dipper, which now stands high in the northeast at nightfall, to navigate to Leo and from there to the queen’s hairdo.