REAL LIFE NEWS: HOW BIG CAN A PLANET BE?
by Hazed
Remember the fuss and bother when Pluto was stripped of its planetary status, demoted to being a dwarf planet? Well, we may have to redefine what makes a planet all over again. This time it’s not tiny rocks that are causing the problem, but giant planets. Just how big can a planet get before it has to be called an ultra-light star?
The question is mired in confusion. Right now, the definition set by the International Astronomical Union (IAU) is that a star should be massive enough for heavy hydrogen (deuterium) to undergo nuclear fusion. That would make a body about 13 times the mass of Jupiter star. So no problem when classifying the planets in the Solar System – this is only an issue with extra-solar bodies.
But researcher Kevin Schlaufman from Johns Hopkins isn’t satisfied that there is a clear cut-off point that divides planets from stars. He points out that sometimes objects smaller than that definition just float around on their own, rather than orbiting a star. So how could they be considered a planet?
His suggestion is to use a different way to define the maximum planet size. “Objects more massive than [around 10 times the mass of Jupiter] should not be thought of as planets,” he says. You can read his reasoning at the source link below.
Source: https://gizmodo.com/we-might-need-to-redefine-planet-again-1822331497