CD-35 2722 B b

The astronomical object CD-35 2722 B b, located 71 lightyears from the Solar system, stirred controversy when it was discovered, over whether it should be considered the first exomoon.^[1]^[2]^[3] Its discoverers called it an "exo-satellite", because the primary object it orbits, CD-35 2722 B is not a planet. CD-35 2722 is a brown dwarf.

It was detected through a detailed analysis of Doppler shifts using a spectroscope mounted on the Very Large Telescope, in Chile.^[3] It orbits its primary every 170 days.

References

↑ "★ Star CD-35 2722". Stellar Catalog. Archived from the original on 2026-07-09. Retrieved 2026-08-08. CD-35 2722 is a star system located approximately 73 light-years from the Sun. The primary star, CD-35 2722 A, is an object with an estimated mass of 0.4 solar masses. The system is notable for its substellar companion, CD-35 2722 B, a brown dwarf—an object too small to sustain the hydrogen fusion that powers typical stars—which serves as the host for the recently identified satellite candidates.
↑ David Kipping (2026-08-07). "We Need to Talk About That "First Exomoon" Discovery". Cool Worlds. Archived from the original on 2026-08-08. Retrieved 2026-08-08 – via YouTube. David Kipping explores the technical and linguistic complexities behind recent claims of discovering a first exomoon. This discussion examines established astronomical classification systems, the criteria for substellar objects, and the challenges inherent in distinguishing between planets and natural satellites in hierarchical star systems.
↑ ^3.0 ^3.1 "Discovery of giant 'exosatellite' challenges our notion of what makes a moon". Physics World. 2026-07-22. Archived from the original on 2026-07-31. Retrieved 2026-08-08. Planetary mass objects around brown dwarfs have been discovered before. Take the example of 2M1207b, which is an object up to six times more massive than Jupiter orbiting a brown dwarf, discovered in 2005 by the Very Large Telescope. Such objects have not been referred to previously as moons or satellites, so why now?

[StellarCatalog-Cd352722-1] "★ Star CD-35 2722". Stellar Catalog. Archived from the original on 2026-07-09. Retrieved 2026-08-08. CD-35 2722 is a star system located approximately 73 light-years from the Sun. The primary star, CD-35 2722 A, is an object with an estimated mass of 0.4 solar masses. The system is notable for its substellar companion, CD-35 2722 B, a brown dwarf—an object too small to sustain the hydrogen fusion that powers typical stars—which serves as the host for the recently identified satellite candidates.

[YouTube-CoolWorlds-2026-08-07-2] David Kipping (2026-08-07). "We Need to Talk About That "First Exomoon" Discovery". Cool Worlds. Archived from the original on 2026-08-08. Retrieved 2026-08-08 – via YouTube. David Kipping explores the technical and linguistic complexities behind recent claims of discovering a first exomoon. This discussion examines established astronomical classification systems, the criteria for substellar objects, and the challenges inherent in distinguishing between planets and natural satellites in hierarchical star systems.

[physicsworld-2026-07-22-3] 3.0 ^3.1 "Discovery of giant 'exosatellite' challenges our notion of what makes a moon". Physics World. 2026-07-22. Archived from the original on 2026-07-31. Retrieved 2026-08-08. Planetary mass objects around brown dwarfs have been discovered before. Take the example of 2M1207b, which is an object up to six times more massive than Jupiter orbiting a brown dwarf, discovered in 2005 by the Very Large Telescope. Such objects have not been referred to previously as moons or satellites, so why now?

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