Celestial hemisphere:  Southern  ·  Constellation: Scorpius (Sco)  ·  Contains:  B273  ·  B275  ·  B278  ·  B283  ·  B286  ·  B287  ·  Butterfly Cluster  ·  HD159595  ·  HD159631  ·  HD159846  ·  HD159897  ·  HD159918  ·  HD160065  ·  HD160095  ·  HD160124  ·  HD160166  ·  HD160167  ·  HD160168  ·  HD160189  ·  HD160202  ·  HD160222  ·  HD160259  ·  HD160260  ·  HD160281  ·  HD160335  ·  HD160371  ·  HD160373  ·  HD160410  ·  HD160461  ·  HD160491  ·  And 175 more.
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Butterfly Cluster, M6 & Ptolomey Cluster, M7 (NGC 6405 & NGC 6475), Paul Lloyd
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Butterfly Cluster, M6 & Ptolomey Cluster, M7 (NGC 6405 & NGC 6475)

Getting plate-solving status, please wait...
Butterfly Cluster, M6 & Ptolomey Cluster, M7 (NGC 6405 & NGC 6475), Paul Lloyd
Powered byPixInsight

Butterfly Cluster, M6 & Ptolomey Cluster, M7 (NGC 6405 & NGC 6475)

Equipment

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Description

Immediately to the North of the Scorpion’s “stinger” lie the two bright open star clusters shown here. These
are naked-eye/binocular objects (in a dark sky), and are, left to right, M7 (Ptolomey’s Cluster) that has been
known from antiquity, and M6 (The Butterfly Cluster), that was recorded much later in 1654. It is possible,
however, that Ptolomey may have observed it. Messier added them to his catalogue of comet-like objects
in 1764.

These are just two bright examples that can be seen when looking through the spiral arm(s) between us
and the central bulge of our galaxy’s core.


Telescope: Canon EF 70-200mm lens + 1.4x extender @ f=140mm
Camera:      ZWO ASI183MC Pro, 40 x 120 sec, no filter
                     Bortle 3-4 sky, moonless (before moonrise)
Field of View: approx. 5º 00’ x 3º 30’
Image processed and prepared in PixInsight and Photoshop Elements

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Butterfly Cluster, M6 & Ptolomey Cluster, M7 (NGC 6405 & NGC 6475), Paul Lloyd