Optolong L-Pro 2" Filter on Sergey's Astrophotography

M13: The Great Globular Cluster in Hercules

Fri, 29 Dec 2023 16:45:00 +0000

This image captures M13, the Great Globular Cluster in Hercules, one of the brightest and best-known globular clusters visible from the northern hemisphere. Lying roughly 22,000 light-years away, this tightly bound sphere of several hundred thousand stars spans about 145 light-years and is among the oldest structures in our galaxy, with an age of over 11 billion years.

The image resolves individual stars from the sparse outer halo all the way into the crowded core, while preserving their natural colors: cool, evolved red giants glow in warm orange tones, contrasting with the hotter blue stars scattered throughout the cluster. First recorded by Edmond Halley in 1714, M13 was also the target of the famous 1974 Arecibo radio message.

M22: The Great Sagittarius Cluster

Thu, 12 Oct 2023 15:14:00 +0000

This image presents M22, the Great Sagittarius Cluster, one of the closest globular clusters to Earth at a distance of roughly 10,600 light-years. Discovered in 1665 by Abraham Ihle, it was one of the very first globular clusters ever recorded, and it is among the brightest in the entire sky.

Because M22 lies in the direction of the galactic bulge, the cluster is framed by an extraordinarily rich background of Milky Way stars, which fill the entire field in a tapestry of blue, white and orange points. Against this crowded backdrop, the cluster’s loosely concentrated core stands out as a bright, glittering ball of ancient stars.

M45: The Pleiades

Wed, 30 Nov 2022 17:14:00 +0000

This image captures M45, the Pleiades, also known as the Seven Sisters, one of the nearest and most recognizable open star clusters in the sky. Located about 440 light-years away in the constellation Taurus, this group of hot, young blue stars formed only around 100 million years ago, making it a true infant on cosmic timescales.

The cluster’s brightest members are enveloped in a striking blue reflection nebula. Rather than being the remnant of the cloud from which the stars were born, this dust belongs to an unrelated interstellar cloud that the cluster is currently passing through, scattering the intense blue starlight. The image reveals the fine, streaky filaments of this dust, especially around Merope and Maia, as well as the fainter nebulosity extending into the surrounding field.