Killing Pluto, Finding Planet Nine

Guest: Mike Brown, PhD, Richard and Barbara Rosenberg Professor of Planetary Astronomy at the California Institute of Technology, Author of “How I Killed Pluto and Why It Had It Coming”  We used to have Pluto, but about 10 years ago, astronomers gave it the boot, saying it’s not quite big enough to warrant the same status as Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. Astronomer Mike Brown was instrumental in killing Pluto’s planetary status. It’s not that he’s got anything against planets, it’s just that he managed to find another one in Pluto’s neighborhood that was even more massive. So, rather than add a tenth planet to the family – Pluto got punted into dwarf planet status, along with Mike Brown’s discovery, called Eris. There’s also dwarf planet called Sedna. Brown discovered that too, along with a couple of others. When it comes to discovering big objects at the edge of our solar system, Brown is one of the most prolific.  Now, he and a colleague, Konstantin Batygin, at the California Institute of Technology have found their biggest yet. A planet they think is nearly as big as Neptune but 20 times further away from the sun.  Brown and his team have yet to actually lay eyes on this giant planet, but their mathematical models and computer simulations have them pretty convinced it’s there. If they turn out to be right, it’ll be an ironic turn for Brown, who wrote a book titled, “How I Killed Pluto and Why It Had It Coming.”