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Pleiades M 45
J. Cocozza
classic. open. cluster. (actually. a. pair. of. them!). is. the.
Double. Cluster. in. Perseus.. Look. for. it. about. midway.
between. Cassiopeia. (the. “W”-shaped. constellation).
and.Perseus.by.simply.sweeping.across.that.area.with.
your.Astroscan. at. 16X..The. Double. Cluster. turns. out.
to. be. two. magnificent. clusters. sprawling. side-by-side.
in.one.low-power.eyepiece.field..The.Summer.and.Fall.
skies. especially. are. so. full. of. open. clusters. that. you.
could. never. run. out. of. wonders. to. see..
The Edmund
Sky Guide
.provides.a.list.of.some.of.the.very.best.ones.
for.viewing.with.your.Astroscan.at.all.four.seasons.of.
the.year..
The.other.type.of.starry.groupings.is.the.“globular.clusters,”.
physically. far. larger. and. more. distant. stellar. beehives.
of.hundreds.of.thousands.to.more.than.a.million.suns..
Because.they.are.so.remote.and.the.stars.in.them.are.
relatively.faint.and.compressed.together,.your.Astroscan.
can.resolve.only.a.few.of.the.brightest.globulars..For.the.
most. part,. they. look. like. soft. woolly. blobs. of. light. that.
occasionally.sparkle..One.of.the.most.striking.of.these.
objects.lies.in.the.constellation.Hercules,.visible.most.of.
the. Spring,. Summer. and. Fall.. Known. as. the. Hercules.
Cluster,.it’s.generally.labeled.on.star.charts.as.“M.13.”.
This.means.it’s.the.13th.object.on.the.list.compiled.by.
the. famous. French. observer. Charles. Messier,. his. “M”.
prefix.adorning.many.of.the.sky’s.most.beautiful.clusters,.
nebulae. and. galaxies.. (The. Pleiades. discussed. above.
is.M.45.on.his.roster.).Point.your.Astroscan.toward.the.
Star Clusters and Asterisms
Tucked. away. among. the. stars. of. the. Milky. Way. are.
dozens. of. aggregations. of. suns. called. star. clusters..
There.are.basically.two.types.of.them,.and.they.don’t.
look.a.bit.alike.in.the.telescope..Most.obvious.are.the.
“open.clusters,”.stellar.jewel.boxes.with.a.few.hundred.
to.a.thousand.or.more.members.that.seem.to.be.loosely.
gathered.together..In.your.Astroscan.an.average.open.
cluster.will.look.somewhat.like.a.small.scattered.pile.of.
salt.on.a.sheet.of.black.paper..Most.open.clusters.lie.
fairly.close.to.the.plane.of.our.galaxy,.so.they.appear.
most.numerous.along.the.Milky.Way..
By.far.the.most.stunning.open.cluster.in.the.entire.sky.is.
the.Pleiades,.a.group.visible.in.the.Fall.and.Winter..It’s.
located.in.the.constellation.Taurus.and.plotted.on.every.
star.map..Once.you’ve.spotted.the.Pleiades.by.eye.(it’s.
fairly.easy.to.see.even.from.city.areas,.appearing.like.
a. little. dipper-shaped. formation. of. stars),. point. your.
Astroscan.at.it..You’ll.be.amazed.at.the.sight.of.six.bright,.
bluish.stars.glowing.like.diamonds.set.in.a.field.of.dozens.
of. fainter. stars. and. hundreds. of. tiny. ones. –. all. filling.
about.half.the.field.of.the.28.mm.(16X).eyepiece..The.
wide. field,. low. magnification. and. large. light-gathering.
power.of.the.Astroscan.combine.to.make.this.cluster.one.
of.the.most.beautiful.spectacles.in.the.heavens!.Close.
by,. also. in. Taurus,. is. a. prominent. V-shaped. cluster.
known.as.the.Hyades..It.includes.the.bright.orange.star.
Aldebaran,. which. actually. lies. much. closer. to. us. than.
the.cluster.itself.and.is.not.one.of.its.members..Another.
