2019-11-01_Sky_and_Telescope

62 NOVEMBER 2019 • SKY & TELESCOPE

M52

M103

King 1

King 2

King 3

King 4

King 12

King 13

King 14

King 15

King 16

King 20

King 21

King 19

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CASSIOPEIA

PERSEUS

CEPHEUS

2 h 30 m 2 h 00 m 1 h 00 m 0 h 00 m

+60°

+55°

1 h 30 m 0 h 30 m 23 h 30 m

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Cassiopeia

Open Clusters

pKING 1 Moving into Cassiopeia,

King 1 stands out from the fi eld. The

brighter stars in the cluster form a small

asterism resembling a kite with a tail —

can you see it? — with some haziness

among the stars.

Mv = 19.3 | S = 9′ | No. = 100 |

Tr = II2r | Mag. = 337×

uKING 2 Located some 26′ northeast of Eta (η)

Cassiopeiae, King 2 is visibly smaller than King 1 and

seems to stand out from the fi eld. I noted only three

brighter stars with a hazy glow around them.

Mv = 19.8 | S = 4′ | No. = 40 | Tr = II2m | Mag. = 337×

uuKING 12 I fi nd that this cluster displays a fairly large

range of brightnesses, and I would classify it as II3p.

Mv = 9 | S = 3′ | No. = 15 | Tr = II1p | Mag. = 73× and 272×

pKING 3 Also known as NGC 609, King 3 is quite faint, adjacent to and slightly northwest of a pair

of 9th-magnitude fi eld stars. I can only resolve a few stars.

Mv = 11 | S = 3′ | No. = 77 | Tr = II3r | Mag. = 282×

qKING 4 Look for this cluster 2′

to 3′ southwest of 9th-magnitude

HD 15979. I caught a hint of it at 77×.

With 337×, it was open and spread

out, concentrated toward the center

with a wide range of star brightnesses,

and poor-to-medium in numbers, as

per its Trumpler rating.

Mv = 10.5 | S = 5′ | No. = 44 | Tr = III1p |

Mag. = 77× and 337×

HD 15979

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