Anthe (moon)

Anthe

Anthe is the ellipsoid in the center
Discovery
Discovered by	Cassini Imaging Team
Discovery date	May 30, 2007
Designations
Designation	Saturn XLIX
Pronunciation	/ˈænθiː/
Named after	Άνθη Anthē
Adjectives	Anthean /ænˈθiːən/
Orbital characteristics
Semi-major axis	197,700 km
Eccentricity	0.0011
Orbital period (sidereal)	1.05089 d
Average orbital speed	13.824 km/s
Inclination	0.1° to Saturn's equator
Satellite of	Saturn
Group	Alkyonides
Physical characteristics
Dimensions	1.8 km
Mean radius	0.9 km
Circumference	≈ 5.7 km
Surface area	10.18 km2
Volume	3 km3
Mass	1.5×1012 kg
Mean density	0.5 g/cm3
Surface gravity	0.00012 m/s2 (0.12 mm/s2)
Escape velocity	≈ 0.56 m/s (≈ 2 km/h)
Synodic rotation period	assumed synchronous

Anthe /ˈænθiː/ is a very small natural satellite of Saturn lying between the orbits of Mimas and Enceladus. It is also known as Saturn XLIX; its provisional designation was S/2007 S 4. It is named after one of the Alkyonides; the name means flowery. It is the sixtieth confirmed moon of Saturn.

The designation S/2007 S 4 was also accidentally and incorrectly used for a different Saturnian satellite discovered later. The published discovery was retracted a few hours later and republished the next day under the correct name of S/2007 S 5.

It was discovered by the Cassini Imaging Team in images taken on 30 May 2007. Once the discovery was made, a search of older Cassini images revealed it in observations from as far back as June 2004. It was first announced on 18 July 2007.

Discovery images of Anthe

Anthe is visibly affected by a perturbing 10:11 mean-longitude resonance with the much larger Mimas. This causes its osculating orbital elements to vary with an amplitude of about 20 km in semi-major axis on a timescale of about 2 Earth years. The close proximity to the orbits of Pallene and Methone suggests that these moons may form a dynamical family.

Material blasted off Anthe by micrometeoroid impacts is thought to be the source of the Anthe Ring Arc, a faint partial ring about Saturn co-orbital with the moon first detected in June 2007.

References

Notes

Citations

Sources

• "Cassini Imaging Science Team". Cassini Imaging Central Laboratory for OPerationS. Archived from the original on 2011-05-20. Retrieved 2012-01-01.
• Agle, D. C. (July 19, 2007). "Saturn Turns 60". Cassini Solstice Mission. JPL/NASA. Archived from the original on February 20, 2012. Retrieved 2012-01-01.
• Green, Daniel W. E. (July 18, 2007). "S/ 2007 S 4". IAU Circular. 8857. Retrieved 2012-01-01.
• Hedman, M. M.; Murray, C. D.; Cooper, N. J.; Tiscareno, M. S.; Beurle, K.; Evans, M. W.; Burns, J. A. (2008-11-25). "Three tenuous rings/arcs for three tiny moons". Icarus. 199 (2): 378–386. Bibcode:2009Icar..199..378H. doi:10.1016/j.icarus.2008.11.001. ISSN 0019-1035.
• Porco C. C.; et al. (2008-09-05). "More Ring Arcs for Saturn". Cassini Imaging Central Laboratory for Operations. Archived from the original on 2008-10-10. Retrieved 2008-09-05.

External links

Media related to Anthe at Wikimedia Commons

• From Dark Obscurity... A Tiny New Saturnian Moon Comes To Light Archived 2011-02-02 at the Wayback Machine