Irregular moons of Saturn -- Tarvos

For notes, see https://tilmanndenk.de/outersaturnianmoons/tarvos/#1

22 Oct 2018 / TD


	Overview Table
Moon name	Tarvos
Saturn range	18e6	km
Orbit period	2.5	years
Orbit direction	prograde
Size ~	15	km
Rotation period	10	41	hh:mm
Discovery year	2000

(A)	Designations and discovery circumstances
(A1)	Moon name	Tarvos
(A2)	Moon abbrev. (TD)	Tar
(A3)	IAU number	Saturn XXI
(A4)	Provisional designation	S/2000 S 4
(A5)	SPICE ID	621
(A6)	Also-used label	S21
(A7)	First observation date	23 Sep 2000
(A7)	Announcement date	25 Oct 2000
(A7)	IAU circular announcement no.	7513
(A8)	Discoverers	Kavelaars, Gladman, et al.

(B)	Orbit parameters
(B1)	Orbit direction	prograde
(B2)	Group member	Gallic
(B3)	Dynamical family	Gallic
(B4)	Periapsis range	8.43e6	km
(B5)	Semi-major axis	18.24e6	km
(B6)	Apoapsis range	28.05e6	km
(B7)	Semi-major axis	302	R_Saturn
(B8)	Semi-major axis	0.122	au
(B9)	Semi-major axis	0.28	R_Hill
(B10)	Orbit eccentricity	0.54	
(B11)	Orbit inclination	33.7	°
(B12)	Inclination supplemental angle	33.7	°
(B13)	Orbital period	926	d
(B14)	Orbital period	2	6	1.75	y:m:w
(B15)	Mean orbit velocity	1.44	km/s

(C)	Physical parameters
(C1)	Mean size ~	15	-3	+4	km
(C2)	Mean radius ~	7.3	km
(C3)	Equatorial circumference ~	50	km
(C4)	Minimum equatorial axes ratio	1.08
(C5)	Axes radii (a x b x c) ~	unknown
(C5)	
(C6)	Mass ~	8e14	kg
(C7)	Mean density (?)	0.5	g/cm^3
(C8)	Surface escape velocity ~	10	km/h
(C9)	Rotation period (sidereal)	10.691	h
(C9)	Rotation period error	0.001	h
(C9)	Spin rate	2.245	d^(-1)
(C10)	Spin direction	unknown
(C11)	Seasons	unknown
(C12)	Pole direction (ecliptic longitude λ)	unknown
(C12)	Pole direction (ecliptic latitude β)	unknown
(C13)	Pole direction (geocentric RA)	unknown
(C13)	Pole direction (geocentric Dec)	unknown
(C14)	Absolute visual magnitude ~	12.9	mag
(C15)	Apparent visual magnitude from Earth	22.1	mag
(C16)	Best apparent magnitude for Cassini	12.8	mag
(C17)	Spectral slope ~	+5.4	%/100nm
(C17)	B-R color index ~	1.21	1.13	
(C18)	Albedo (?)	0.06	
(C19)	Hill sphere radius ~	650	km
(C20)	Hill sphere radius ~	90	r_Tar