study shows no noticeable difference between gas giants and brown dwarfs in mass–radius trends: from approximately one Saturn mass to about (the onset of hydrogen burning), radius stays roughly constant as mass increases, and no obvious difference occurs when passing . By this measure, brown dwarfs are more like planets than they are like stars. Planetary-mass stellar objects The ambiguity inherent in the IAU's definition was highlighted in December 2005, when the Spitzer Space Telescope observed Cha 110913-773444 (above), only eight times Jupiter's mass with what appears to be the beginnings of its own planetary system. Were this object found in orbit around another star, it would have been termed a planet. In September 2006, the Hubble Space Telescope imaged CHXR 73 b (left), an object orbiting a young companion star at a distance of roughly 200 AU. At 12 Jovian masses, CHXR 73 b is just under the threshold for deuterium fusion, and thus technically a planet; however, its vast distance from its parent star suggests it could not have formed inside the small star's protoplanetary disc, and therefore must have formed, as stars do, from gravitational collapse. In 2012, Philippe Delorme, of the Institute of Planetology and Astrophysics of Grenoble in France announced the discovery of CFBDSIR 2149-0403; an independently moving 4–7 Jupiter-mass object that likely forms part of the AB Doradus moving group, less than 100 light years from Earth. Although it shares its spectrum with a spectral class T brown dwarf, Delorme speculates that it may be a planet. In October 2013, astronomers led by Dr. Michael Liu of the University of Hawaii discovered PSO J318.5-22, a solitary free-floating L dwarf estimated to possess only 6.5 times the mass of Jupiter, making it the least massive sub-brown dwarf yet discovered. In 2019, astronomers at the Calar Alto Observatory in Spain identified GJ3512b, a gas giant about half the mass of Jupiter orbiting around the red dwarf star GJ3512 in 204 days. Such a large gas giant around such a small star at such a wide orbit is highly unlikely to have formed via accretion, and is more likely to have formed by fragmentation of the disc, similar to a star. Semantics Finally, from a purely linguistic point of view, there is the dichotomy that the IAU created between 'planet' and 'dwarf planet'. The term 'dwarf planet' arguably contains two words, a noun (planet) and an adjective