Astronomy - USA (2020-05)

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his month, we’ll visually thread our way


through the extragalactic haystack that’s


now prominent along the meridian. We’ll focus


on three types of spiral galaxies: grand-design


(those with striking spiral arms), f locculent


(those that appear “f luffy”), and edge-on or


near-edge-on (those whose orientation doesn’t


allow us to see their disks). I call the first two types


“pins” and the third “needles.”


The galaxies in this hunt run the gamut from strik-


ing to elusive. To approach this galactic scavenger hunt


in a systematic way, I’ve divided the sky into four sec-


tions. In each section, we’ll follow a one-to-one extra-


galactic stitch pattern — first a needle, followed by a


pin — looping our way from one region of sky to the


next. (And in an effort to introduce you to some lesser-


known beauties, none of the objects discussed below is


on Messier’s famous list.) Let the needlework begin!


Hunting pins and needles in the deep sky


will give your observing some pizzazz.


BY STEPHEN JAMES O’MEARA


EDGE-ON AND


FACE-ON GALA XIES


56 ASTRONOMY • MAY 2020


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