Ast101 Tutorial - November 21.pdf

2 Pages
Unlock Document

Astronomy & Astrophysics
Michael Reid

Ast101 Tutorial November 21, 2012 Orbital Resonances - resonance is when things line up - when bodies are lined up, the distance between them is minimized. This means that the gravity between them is stronger - at the points where these bodies line up, the interactions between them are maximized - resonances can be stable or unstable - e.g. unstable resonance: gaps in Saturn's rings - 1:2:4 will be in resonance, 1:2.5:6.7 will not - they must be integer ratios - Io's orbit is elliptical. When it is closer to Jupiter, the gravity between the two is stronger and therefore it has larger tidal bulges ▯ - this heats the inside of Io ▯ - the heating comes from friction inside Io ▯ - this warm interior allows surface activity to occur ▯ - e.g. Io has many volcanoes ▯ - therefore it has a young surface - Callisto does not have this tidal heating, and therefore has an older surface and many craters - resonances are cases where there is enhanced gravitational influence between bodies. Objects can experience tidal heating from elliptical orbits, and can create gaps (in rings, asteroid belts, etc.) The Sun - a star born in a molecular gas cloud that collapsed and due to self-gravity compressed itself to become a proto-star - the centre heats up to the point where nuclear
More Less

Related notes for AST101H1

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.