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Vesta Is a Baby Planet, Not an Asteroid
astroengine writes "Vesta, the second largest object in the main asteroid belt, has an iron core, a varied surface, layers of rock and possibly a magnetic field — all signs of a planet in the making, not an asteroid (abstract). This is the conclusion of an international team of scientists treated to a virtual front row seat at Vesta for the past 10 months, courtesy of NASA's Dawn robotic probe. Their findings were presented during a NASA press conference on Thursday. As to why Vesta never made it to full planethood, scientists point to Jupiter. When the giant gas planet formed, nearby bodies such as Vesta found their orbits perturbed. 'Jupiter started to act like a spoon in a pot, stirring up the asteroid belt and the asteroids started bumping into one another,' said Dawn lead scientist Christopher Russell. 'If they're just out there gently orbiting and everything is going smoothly, then without Jupiter in the picture, they would gather mass and get bigger and bigger and bigger. But with Jupiter there, stirring the pot, then the asteroids start bumping into one another and breaking apart, so nothing grew in that region, but started to shrink.'"
So Pluto was deemed just another large chunk of space debris orbiting the earth, and hence not a planet. Vesta *is* just a large asteroid amongst a whole bunch of others, but it is a planet?
I'm confused now.
That would have turned Mars into an asteroid belt ... and Earth into an undersized Mars.
And since Venus is just too darn close to the sun to support life ... another lifeless solar system.
Let's call it what it is, Anti-Social Media.
You think this bone you're throwing to Vesta is going to make us forgive what you did to poor Pluto?
10 PRINT CHR$(205.5+RND(1)); : GOTO 10
Please don't tell Neil deGrasse Tyson about this or he will kill baby Vesta safe just like he killed its older sibling Pluto. This man is worse than the Pharaoh!
Dr. Neil deGrasse Tyson on killing Pluto: 'All I did was drive the getaway car'
http://www.theverge.com/2012/3/26/2903224/dr-neil-degrasse-tyson-killing-pluto-on-the-verge
it's a cynical quote, because it's not really true: principles actually define winners and losers
but it certainly applies to planet formation
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
And if a group of pro-Plutoans happen to make Neptune...disappear...does Pluto still get planetary status?
The whole problem with finding a definition of 'planet' is that stuff in the solar system can either be defined by its composition or its location. Objects with similar composition that look like exactly the same sort of thing when seen in isolation are often found in very different locations. And the IAU decided in its infinite wisdom to use location as the primary means classification rather than composition. Unfortunately, that decision is at odds with both sentimentality (as is seen with the whole Pluto fiasco) and with scientific usefulness. As we study extrasolar planetary systems, it has become clear that objects orbiting stars are very likely to change locations over time. Objects move from higher orbits to lower orbits and vice versa, Objects are captured into orbit by other objects, and objects are ejected from orbit around other objects, etc. So when studying a solar system, classifying objects by where they are in the system is scientifically meaningless as the objects quite possibly did not form in that location, and certainly may not remain in that location for the lifetime of the system's star.
So I propose Harperska's planetary classification system:
Terrestrial dwarf - large enough to attain hydrostatic equilibrium and differentiation. Mantle/crust comprised of rock, with iron core. 6 objects in solar system: Mercury, Venus, Earth, Luna, Mars, Vesta.
Asteroid - terrestrial dwarf like object, not large enough to attain hydrostatic equilibrium.
Ice dwarf - large enough to attain hydrostatic equilibrium and differentiation. Mantle/crust comprised of frozen volatiles (water, methane, ammonia), with rocky core. This class includes Ceres, the moons of the gas and ice giants, and Kuiper belt objects like Pluto and Eris.
Comet - ice dwarf like object, not large enough to attain hydrostatic equilibrium.
Gas Giant - comprised largely of hydrogen and helium. 2 objects in solar system: Jupiter and Saturn.
Ice Giant - comprised largely of volatiles (water, methane, ammonia) with a hydrogen/helium atmosphere. 2 objects in solar system: Neptune and Uranus.