A Twin Jewel of the Northern Sky
The Double Cluster consists of two bright open clusters, NGC 869 and NGC 884, separated by only a few hundred light-years. While they weren't included in Messier's catalog (likely because they were too obviously not comets), they have been cataloged since 130 BC by Hipparchus. Both clusters are physically young—only about 13 million years old—and are filled with massive, hot blue-white supergiant stars. They are located in the Perseus spiral arm of our galaxy and serve as a stunning example of simultaneous star formation on a massive scale.
Imaging Challenges
- • Framing both clusters symmetrically within the FOV while leaving enough 'breathing room' for the surrounding star field.
- • Balancing the processing to highlight the few prominent red giant stars that provide a beautiful color contrast against the blue-white majority.
- • Managing the sheer density of stars to prevent the image from looking cluttered or 'noisy' during sharpening.
Both clusters are blue-shifted, meaning they are currently screaming toward Earth at a speed of roughly 38 kilometers per second.