two-nice-double-stars-open-cluster-ngc-2414-and-the-medusa-nebula-abell-21https://www.astronomy.com/observing/deep-sky-objects/page/30/Deep-Sky Objects | Page 30 of 49 | Astronomy.comDeep-sky objects are celestial objects that exist outside our solar system. Three major types of deep-sky objects are nebulae, star clusters, and galaxies.https://www.astronomy.com/uploads/2021/09/stardome330.gifInStockUSD1.001.00deep-sky-objectsstarsarticleASY2023-05-182015-02-1246776
Deep-sky objects are celestial objects that exist outside our solar system. Three major types of deep-sky objects are nebulae, star clusters, and galaxies.