Messier 10 (Ophiuchus)

Fig. 1 - High population of blue stragglers (stars that appear younger than their neighbors): Messier 10 in Ophiuchus, photographed with a 16-inch f/4.5 Dob on an equatorial platform.

Fig. 1 - High population of blue stragglers (stars that appear younger than their neighbors): Messier 10 in Ophiuchus, photographed with a 16-inch f/4.5 Dob on an equatorial platform.


Object name:Constellation:Coordinates:Apparent size:Visual brightness:
Messier 10 (NGC 6254)Ophiuchus16h57m / -04°06'20'6.6 mag


The globular cluster Messier 10 (NGC 6254) in the constellation Ophiuchus. Messier 10 is the second brightest globular cluster in Ophiuchus and is estimated to be 14,300 light-years away from Earth. Its spatial diameter is approximately 83 light-years. Messier 10 was discovered by French astronomer Charles Messier in 1764 (source: Wikipedia).

Exposure time: 1h 10min (70x1min) at gain 100 and -10°C, taken on June 25 / 26, 2023, were added for this shot with the Astro Pixel Processor (APP) software and the final image processing was done in Photoshop. Darks, flats, bias and dark flats were used.

Equipment: Cooled ASI 2600MC Pro camera, TeleVue Paracorr Type II coma corrector, 16" f/4.5 "Ninja" dobsonian telescope riding on a dual-axis Tom Osypowski equatorial platform, Lacerta MGEN autoguider, Lacerta off axis system.

Field of view comparison: image of the moon with the same equipment.

Fig. 2 - Search chart for Messier 10. Copyright 2025 'The Mag-7 Star Atlas Project', www.siaris.net.

Fig. 2 - Search chart for Messier 10. Copyright 2025 'The Mag-7 Star Atlas Project', www.siaris.net.