I’m going to come right out and ask the burning question: Is Pluto a Planet? No. At least under the current definition. So the question becomes “Should Pluto be a planet?” That answer is a bit more complicated. Let’s look at the history. Discovered by Clyde Tombaugh in 1930, Pluto was initially considered the ninth planet of our Solar System. It was part of an intense search that follows back all the way to the discovery of Uranus and the orbital calculations that led to the discovery of Neptune. Even after Neptune’s discovery, gravitational perturbations pointed to a ninth planet,...
Dark matter could be almost anything. With little data other than how much total dark matter mass exists, we can’t decode much about what individual chunks of dark matter might be made of. I’ve talked before about Massive Compact Halo Objects (MACHOs) and Weakly Interacting Massive Particles (WIMPs), but these are just two possibilities. Other theorists have talked about Modified Newtonian Gravity (MNG), where gravity may work differently on the grand scale than it does on our small Earth scales. Or perhaps it’s something I haven’t seen before. Maybe what we call dark matter is just a large population of ancient black holes....
How do stars lose mass? For a star like the Sun, it shoots out a swath of charged particles into space and sheds mass at a rate of 4 million tons per second! Though even at this rate, the Sun only loses 1% of its total mass every 160 Billion years, so it’s not disappearing anytime soon. For more massive stars, the process can become complex and strange. The red hypergiant VY Canis Majoris, one of the largest known stars, is about 40 times as massive as the Sun, but humungous in scale. If this star were to replace the...
