Open Cluster M18 (also known as Messier Object 18, Messier 18, M18, or NGC 6613) is an open cluster in the Sagittarius constellation. It was discovered by Charles Messier in 1764. M18 is situated between the Omega Nebula M17 and the Star Cloud M24. Its age is estimated at 32 million years.

Atlas Image obtained as part of the Two Micron All Sky Survey (2MASS), a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation.

• Source: The Two Micron All Sky Survey at IPAC
• License: Please note: The images in this gallery are released into the public domain. If any image or images are redisplayed or reproduced, please accompany the image or images with the following acknowledgment: "Atlas Image [or Atlas Image mosaic] obtained as part of the Two Micron All Sky Survey (2MASS), a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation." This is the stated policy of 2MASS.

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