BBC Sky at Night

DEEP-SKY TOUR

1 M71

Sagitta, the Arrow does look like an arrow with an isosceles triangle forming the flight and the shaft represented by the line from Delta (δ) to Gamma (γ). Globular cluster Messier 71 sits south of the mid-point.

M71 is an eighth-magnitude object. At powers of 200x, a 150mm instrument resolves some of M71’s stars, a trend which increases with aperture. Curiously it looks more like

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