Viewing Solar System Orbital Architecture through an Extrasolar Lens
Δημοσιεύτηκε στις 16 Απρ 2015
Viewing Solar System Orbital Architecture through an Extrasolar Lens - Konstantin Batygin - SETI Talks
The
statistics of extrasolar planetary systems indicate that the default
mode of planetary formation generates planets with orbital periods
shorter than 100 days, and masses substantially exceeding that of the
Earth. When viewed in this context, the Solar System, which contains no
planets interior to Mercury’s 88-day orbit, is unusual.
Extra-solar
planetary detection surveys also suggest that planets with masses and
periods broadly similar to Jupiter’s are somewhat uncommon, with
occurrence fraction of less than approximately 10%.
In this talk,
Dr. Batygin will present calculations which show that a popular
formation scenario for Jupiter and Saturn, in which Jupiter migrates
inward from a greater than 5AU to approximately 1.5 AU and then reverses
direction, can explain the low overall mass of the Solar System’s
terrestrial planets, as well as the absence of planets with a less than
0.4 AU. Jupiter’s inward migration entrained s greater than 10 − 100 km
planetesimals into low - order mean-motion resonances, shepherding of
order 10 Earth masses of this material into the a ∼ 1 AU region while
exciting substantial orbital eccentricity (e ∼ 0.2 − 0.4).
He
will argue that under these conditions, a collisional cascade will
ensue, generating a planetesimal disk that would have flushed any
preexisting short-period super-Earth-like planets into the Sun. In this
scenario, the Solar System’s terrestrial planets formed from gas-starved
mass-depleted debris that remained after the primary period of
dynamical evolution.
The
statistics of extrasolar planetary systems indicate that the default
mode of planetary formation generates planets with orbital periods
shorter than 100 days, and masses substantially exceeding that of the
Earth. When viewed in this context, the Solar System, which contains no
planets interior to Mercury’s 88-day orbit, is unusual.
Extra-solar
planetary detection surveys also suggest that planets with masses and
periods broadly similar to Jupiter’s are somewhat uncommon, with
occurrence fraction of less than approximately 10%.
In this talk,
Dr. Batygin will present calculations which show that a popular
formation scenario for Jupiter and Saturn, in which Jupiter migrates
inward from a greater than 5AU to approximately 1.5 AU and then reverses
direction, can explain the low overall mass of the Solar System’s
terrestrial planets, as well as the absence of planets with a less than
0.4 AU. Jupiter’s inward migration entrained s greater than 10 − 100 km
planetesimals into low - order mean-motion resonances, shepherding of
order 10 Earth masses of this material into the a ∼ 1 AU region while
exciting substantial orbital eccentricity (e ∼ 0.2 − 0.4).
He
will argue that under these conditions, a collisional cascade will
ensue, generating a planetesimal disk that would have flushed any
preexisting short-period super-Earth-like planets into the Sun. In this
scenario, the Solar System’s terrestrial planets formed from gas-starved
mass-depleted debris that remained after the primary period of
dynamical evolution.
Κατηγορία
Άδεια
- Τυπική άδεια YouTube
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