Celestial hemisphere:  Southern  ·  Constellation: Scorpius (Sco)  ·  Contains:  B273  ·  B275  ·  B278  ·  B283  ·  B286  ·  B287  ·  B288  ·  Butterfly Cluster  ·  G Sco  ·  M 6  ·  M 7  ·  NGC 6396  ·  NGC 6400  ·  NGC 6404  ·  NGC 6405  ·  NGC 6416  ·  NGC 6425  ·  NGC 6441  ·  NGC 6444  ·  NGC 6453  ·  NGC 6455  ·  NGC 6475  ·  PK353-02.1  ·  PK353-02.2  ·  PK353-03.1  ·  PK353-03.2  ·  PK353-04.1  ·  PK353-04.2  ·  PK353-05.1  ·  PK353-05.2  ·  And 47 more.
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M6 - Butterfly Cluster and M7 - Ptolemy's Cluster, Paul Ricker
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M6 - Butterfly Cluster and M7 - Ptolemy's Cluster

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M6 - Butterfly Cluster and M7 - Ptolemy's Cluster, Paul Ricker
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M6 - Butterfly Cluster and M7 - Ptolemy's Cluster

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Description

M6, the Butterfly Cluster, is an open cluster with about 120 confirmed members at a distance of about 500 pc, while M7, Ptolemy's Cluster, is another open cluster about 300 pc away. M7 is the southernmost Messier object and was known to the Greek astronomer Ptolemy. This seems remarkable to me given its location in front of the dense star clouds of the central Milky Way at the tip of Scorpius's tail.

Interestingly, only one of the two yellow objects at the lower right is a star, Fuyue (G Scorpii). The other is NGC 6441, a globular cluster (!) at a distance of 13.5 kpc.

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M6 - Butterfly Cluster and M7 - Ptolemy's Cluster, Paul Ricker