Saturn's Rings: An Accessible Astrophysical Disk - Matthew Tiscareno (SE...
Δημοσιεύτηκε στις 3 Απρ 2015
Saturn's
ring system is an astrophysical disk that is neither light-years away
nor billions of years in the past. We can visit this disk at close range
and observe a number of phenomena that also operate in disks of other
kinds. As a result, we see small-scale processes that shape ring
texture, connect those processes to the bodies and structures that cause
them, and watch closely as the disk changes with time.
We will
discuss recent Cassini observations that elucidate disk processes
including 1) "self-gravity wakes" and "spiral density waves," both of
which were originally proposed for galaxies but are observed with
exquisite precision in Saturn's rings, 2) "propeller" features caused by
100-meter to km-sized moonlets embedded in the disk; these are the
first objects ever to have their orbits tracked while embedded in a
disk, rather than orbiting in free space, and hold the potential of
deepening our understanding of planetary migration, and 3) irregular
edge shapes in the gaps opened up by larger moons (10 km and more),
which may hold clues to angular momentum transport.
ring system is an astrophysical disk that is neither light-years away
nor billions of years in the past. We can visit this disk at close range
and observe a number of phenomena that also operate in disks of other
kinds. As a result, we see small-scale processes that shape ring
texture, connect those processes to the bodies and structures that cause
them, and watch closely as the disk changes with time.
We will
discuss recent Cassini observations that elucidate disk processes
including 1) "self-gravity wakes" and "spiral density waves," both of
which were originally proposed for galaxies but are observed with
exquisite precision in Saturn's rings, 2) "propeller" features caused by
100-meter to km-sized moonlets embedded in the disk; these are the
first objects ever to have their orbits tracked while embedded in a
disk, rather than orbiting in free space, and hold the potential of
deepening our understanding of planetary migration, and 3) irregular
edge shapes in the gaps opened up by larger moons (10 km and more),
which may hold clues to angular momentum transport.
Κατηγορία
Άδεια
- Τυπική άδεια YouTube
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου