Scutum – the shield

There is a small rectangular region in the summer sky known as Scutum, the shield. It represents a typical shield ranging from the Roman legionnaire sort to one that ye olde knight of chivalry might carry along with so much armor he needs a crane to get on a horse. The medieval warriors of Europe were so obsessed with defense they forgot to invent stirrups. Eventually they traded their fixed-defense tactics for an increase in scope and mobility, but the shield remained as a symbol of the honor of service to the defense of the homeland. After all, it’s one thing to go to war, it’s another thing when war comes to you.

Let’s suspend the military model for what’s really interesting in Scutum, which is the Wild Duck Cluster (M11). It’s an open cluster of young stars. Gottfried Kirch discovered the cluster in 1681 but later a British Royal Navy Admiral named Smyth expressed that he thought the brighter stars in the group looked like a bunch of ducks playing follow-the-leader.

I know the word “bunch” isn’t the proper collective noun but I’ve noticed that when my own ducks are paddling around on our pond, one will randomly decide to head to the other end and the others will assume he is the new captain and “bunch up” behind and follow, roughly forming them into an armada and okay now I’m being militant again. Basically it’s how ducks have elections. Admiral Smyth must have noticed the similarity between these stars and his own ducks and likewise he surely understood the inherent tactical disadvantage of that formation in the face of Spanish aggression.

To get the duck effect, use binoculars and ignore the dimmer stars, otherwise there are way too many ducks, almost 3000. The cluster is in the Sagittarian Arm of the Milky Way which is a very popular pond. If Earth was orbiting a star in a cluster like this there would essentially be no night. That would suck for astronomy.

There is another open cluster to be had here, M26. It is actually a fairly decent object for an amateur telescope although it isn’t shaped like ducks or anything. It just looks like someone spilled some salt on a black granite counter-top. The most interesting thing about this cluster is that there is a big bubble of nothing in the middle, no stars, nothing. It’s a pretty weird thing for an open cluster to have an empty middle like that. I mean, the core of a star cluster is like the center of the board in chess, it’s the high ground in battle, it radiates power and dominance. Normally stars gravitate to the middle, literally. So the big bubble in M26 calls for some kind of explanation. So far I’ve yet to hear one. If you come up with your own theory, be prepared to defend it.

Carpe Noctem.