First moon found beyond solar system is as big as a planet, Pg13

Key Highlights:

• Astronomers have identified the first plausible exomoon candidate, orbiting a brown dwarf outside our solar system.
• The newly discovered object is estimated to be approximately 90% as massive as Jupiter.
• This exomoon candidate orbits its host, the brown dwarf CD-35 2722 B, every 170 days.
• The detection was achieved using the Radial Velocity Method, a technique that measures gravitational wobbles.

Exomoon.jpg

Detailed Insights:

• The exomoon candidate is part of a unique three-tiered hierarchical system, orbiting CD-35 2722 B, which itself orbits a star named CD-35 2722.
• Its planet-like mass challenges existing astronomical definitions, blurring the distinction between a moon and a planet.
• The International Astronomical Union (IAU) currently lacks a formal definition for moons in such complex systems, highlighting a gap in celestial classification.
• The discovery was made by observing subtle changes in the brown dwarf's motion, caused by the gravitational pull of the orbiting body.
• Observations were conducted using the European Southern Observatory's Very Large Telescope (VLT) in Chile.

Scientific/Technical Concepts Involved:

• Radial Velocity Method: An indirect method to detect exoplanets or exomoons by observing Doppler shifts in the spectrum of a star or brown dwarf, caused by its gravitational wobble.
• Brown Dwarf: A celestial object with a mass between that of a large planet (like Jupiter) and a small star, capable of fusing deuterium but not hydrogen.
• Exomoon: A natural satellite orbiting an exoplanet or other non-stellar extrasolar body beyond our solar system.