NGC 6426

Right Ascension	17 : 44.9 (h:m)
Declination	+03 : 00 (deg:m)
Distance	67.2 (kly)
Visual Brightness	11.2 (mag)
Apparent Dimension	3.2 (arc min)

Discovered by William Herschel in 1781.

Globular cluster NGC 6426 was discovered by William Herschel on July 16, 1781 with his 6.2-inch reflector (7-ft. FL), as one of his early objects found before he started his systematical survey for nebulae and clusters. Just noticing but not cataloging the object, he found it again on June 3, 1786 with his .7-inch reflector of 20-ft FL, the standard instrument used in his great survey, and cataloged it as H II.587. It was missed by his son John Herschel in all his catalogs including the GC of 1864, so it was found independently by Jean Marie Edouard Stephan in Marseille on July 13, 1876; that observation entered the GC extension (Dreyer 1877) as GC 5870.

According to modern measurements, globular cluster NGC 6426 is at a distance of about 67,200 light-years from us, beyond and at 46,900 light-years from the Galactic Center. Its mass has be determined at 70,000 solar masses, its half-mass radius as 25.7 light-years, and its age at 13 billion years. It orbits the Galactic Center in about 220 million years on an excentric orbit between about 12,000 and 55,000 light-years. 16 variable stars have been found in the field of NGC 6426 to 2015, 13 of them certain cluster members, all of RR Lyrae type.

The image in this page was obtained by Martin Germano with an 8" f/5 Newtonian reflector and ST-8XME self-guided CCD camera and Red filter, exposed 200 minutes.

.. more to come ..

Wikipedia page for NGC 6426

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Hartmut Frommert
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Last Modification: July 26, 2026