Messier 71

Observation Notes:

Through the 25 mm eyepiece, this globular cluster was dim and small, but still remarkably grainy. It was also elongated. In the 10 mm eyepiece a number of stars showed at the edges and a few across the face. The shape was irregular, and seemed to make a soft arrowhead pointing WSW. An asterism of 4 stars across the surface points WSW too and leads to another line of 3 stars outside, pointing in the same direction. Not sure, but it looks like there is a detached clump of stars to the north with 3 brighter stars involved.

Factoids:

There has been a lot of confusion as to whether M71 should be considered a loose globular, or a dense open cluster. Not just because it is pretty loose for a globular, but also because it has a high metal content (only M69 has more), and it is fairly small at 27 light years across. Currently, it is considered to be a globular. It is 13,000 light years away, and is approaching at roughly 23 km/sec. M71 was first seen by De Chéseaux in 1746, and then catalogued by Charles Messier in 1780, and then first resolved into stars by William Herschel in 1783.

SubjectM71/NGC 6838
ClassificationGlobular Cluster
PositionSagitta [RA: 19:53.8 / Dec: +18:47]*
Size*7.2'
Brightness*8.2
Date/Time10/4/04 - 9:30 PM
Observing Loc.Flagstaff, AZ - Home
InstrumentOrion SVP 6LT Reflector (150 mm dia./1200 mm F/L)
Eyepieces/Mag.25 mm (48X); 10 mm (120X)
Seeing4/10
TransparencyMag 5

* Based on published data.

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This page contains a single entry by Jeremy Perez published on October 4, 2004 9:30 PM.

Messier 54 was the previous entry in this blog.

Messier 32 - Satellite of the Andromeda Galaxy is the next entry in this blog.

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