The Geminid Meteor Shower is rare in that its parent body, 3200 Phaethon, is an asteroid, not a comet. Most meteor showers are generated by particles expelled from comets by solar heating and evaporation. In Phaethon?s case, the mechanism is less obvious. The team previously explained mass loss at 101955 Bennu as arising due to micrometeoroid impacts from comet particles. The team will now model this idea for Phaethon using NASA?s Meteoriod Engineering Model (MEM). Their hypothesis is that the Geminids are formed through micrometeorite impacts, causing Phaethon to leave a trail of particles, much like a comet. The team will also model mass loss and evolution for weakly-bound primitive bodies that pass close to the Sun. The team will also participate in SwRI?s Summer Science Program (SSP) and conduct a two-day computational session for high-school students in the program.
The team will use NASA?s Meteoroid Engineering Model to model micrometeoroid impact on a weak primitive surface as is thought to represent 3200 Phaethon in a region at 0.14 AU from the Sun. In prior work with MEM, the team found mm-sized meteoroids strike Bennu frequently enough at > 40 km/s to explain all particle ejection event constraints. Using the Bennu study to guide their work, the team will (i) use the MEM model to determine the mass/direction of ejected debris from Phaethon per perihelion passage, (ii) use dynamical models to determine whether Phaethon debris can reproduce the Geminids over the last ~1000 years, and (iii) use dynamical models to explore Phaethon?s origin, which they argue is probably not from the Pallas asteroid family.
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