TW Hydrae association

The TW Hydrae association is a group of very young low-mass stars and substellar objects located approximately 25–75 parsecs (80–240 light years) from Earth. They share a common motion and appear to all be roughly the same age, 10±3 million years old. It is the youngest such association within 100 pc from Earth.

As of 2017, 42 objects (in 23 systemsSingular objects are also regarded as "systems" here.) are assigned to the association confidently, and several dozens — uncertainly. Masses of its known members vary from 5 Jupiter masses to 2 solar masses, and their spectral types vary from A0 to L7.

Some of the best studied members of this stellar association are TW Hydrae (nearest known accreting T Tauri star to the Earth), HR 4796 (an A-type star with resolved dusty debris disk; the most massive known group member), HD 98800 (a quadruple star system with debris disk), and 2M1207 (accreting brown dwarf with remarkable planetary-mass companion 2M1207b).

Included in the association is WISEA 1147, which is a brown dwarf.{{cite news|last1=Newcomb|first1=Alyssa|title=Lonely Planet Unattached to a Star Found in Deep Space|url=https://abcnews.go.com/Technology/lonely-planet-unattached-star-found-deep-space/story?id=38542912|accessdate=21 April 2016|work=ABC News|date=20 April 2016}}{{cite news|title=Lone Planetary-Mass Object Found in Family of Stars|url=http://www.nasa.gov/feature/jpl/lone-planetary-mass-object-found-in-family-of-stars|accessdate=21 April 2016|work=NASA|date=19 April 2016}}{{cite news|last1=Kennell|first1=Joanne|title=Astronomers Spot a Lonely Planet-Like Object Floating Freely in Space|url=http://thescienceexplorer.com/universe/astronomers-spot-lonely-planet-object-floating-freely-space|accessdate=21 April 2016|work=The Science Explorer}}