Upload
others
View
2
Download
0
Embed Size (px)
Citation preview
Planetary Sciences Class #2
STA → # 13
Tides-
Fm : GMM.
r
:r#.
Mn Mz
DF = F- Fz =off
. dr = -
26Mr#dr
Center : Fe=
6Y÷nEt 05
> FxF
↳R ?it'
*--5in- - - . - . -. -
.?:
C
r
Fpm- GMT asp
SZ
Fpy = - GMT sin $52
Differentialforce between center and
surface is
DF = Fp - Fc
= 6mm (age - de ) ie .
6sM÷n s in ffS
Kodiak 5¥;Ioriotitration: r
' [ I + Id-
2R= oso ]s2= ryn - 2 ; oso )DF= 6=Mqfood (t +2¥ Gso ) -
1 ) si
-
6nn= [ l +
2yd oso] Sino jFor cost a I
,sin + = Rsi¥t
DF =
6M=3R ( Zoso I -sino 5 )
Europe ; en deuce for non - synchronous rotation
Roche limit
÷del
force
supplants internal forces holdingbody
together
we < 26 Mprm.
r3grainy oh tidal fee
surface from planet3
Mr3< ZMI Rm
P Mm
Mn .Rx r3< 2fjR÷n*#÷z
"3#g)"3Rp-
.
Osefl because we an mecuse pj and RJ( and estimate f. better Hren Nl Can mm end Rm )
.
True value not 2113=1 ] but ~ 2.456.
For saturn;
r - 1.23×10 8m
Planets imaltrueSelf - gravity of
dust to overcome the solartide
gyp>2¥34p¥r±kzn÷K.
pp > 2Mg
. ¥- 05my
Boosting ) no ftp..to ,
neo 's Mao )#P ME
a±v→§uf÷o)nf±€
.
M xp . ✓ = pn .
.
4§ rp
=p .4
Izrp'
R = RH = a ¢±*Tb 3
kafyhz )N =p .
¥ " FHER,!p .
pre /4IzR+3
p. ) "I=p. r,?
Mdb
Pra # " Hhs,,=p%p←RP = piney,
# "' ¥"
Rt=fII#nni"H÷M3mi2" ¥43
axv→§uf÷o)nf±€
Suppose that the collapse happens vertically ,so
that p changes but E stays the same
3 3MNEDna⇐notp
Mn no't :4Ceres Mass ~ 10 g
Very low density. Asteroids here densities
q the order of no"
gkm ?
Pr Rr →p.
R.
The mass that collapses rmouidtg ,compared to Ceres Mass ~ Mae , -1024g
MaEKED not
Mo.reakhzep - not
so Rc ~ ( lost ) 'sRanes should be the typical
radius of a dust ball produced by
gravitationalinstability . Ceres radius being roughly 500 km
,we he
:( ix 163.pe ~ 2.5km
so,
plateletsshould se -5kmin size
.