Results from Our Irregular Satellite Survey

  1. S. Sheppard and D. Jewitt (2003). An Abundant Population of Small Irregular Satellites Around Jupiter. Nature, 423, 261-263. pdf version

    We performed a wide field survey of Jupiter, increasing its known population of irregular satellites from 9 to 48. The new satellites are dynamically clustered into ~6 groups, suggesting the collisional shattering of precursor bodies.

  2. D. Jewitt, S. Sheppard and C. Porco (2004). Jupiter's Outer Satellites and Trojans, Chapter 12 in JUPITER 2, edited by Fran Bagenal, Cambridge University Press, Cambridge. pdf version

    We wrote a synthesis paper, attempting to draw connections between the irregular satellites of Jupiter, its temporary satellites (most famous example is comet Shoemaker-Levy 9) and its 1:1 resonators, the famous Trojan asteroids.

  3. S. Sheppard, D. Jewitt and J. Kleyna (2004). A Survey for Outer Satellites of Mars: Limits to Completeness. Astronomical Journal, 128, 2542-2546 pdf version

    We surveyed Mars for irregular satellites. None were expected and none were found. Still, you never know until you've looked.

  4. D. Jewitt and S. Sheppard (2005). Irregular Satellites in the Context of Giant Planet Formation. ISSI Conference on the Outer Solar System. Ed. R. Kallenbach, Space Science Reviews, 116, 441-456. pdf version

    We used the observed systematics of the irregular satellite populations of the four giant planets to make judgements about the proposed hypotheses for satellite capture. The "standard" model of capture by gas drag might work around gas giants Jupiter and Saturn, but seems strained at ice giants Uranus and Neptune, where there is not much gas. Likewise we reject pull-down capture as an explanation for Uranus and Neptune irregular satellites. Our most surprising result is that all 4 giants hold about the same number of irregular satelllites, independent of planet mass or formation mode.

  5. S. Sheppard, D. Jewitt and J. Kleyna (2005). Ultradeep Survey for Irregular Satellites of Uranus: Limits to Completeness. Astronomical Journal, 129, 518-525. pdf version

    We took advantage of unusually fine seeing and the fantastic Subaru telescope to survey Uranus to great depth (red magnitude 26.1).

  6. S. Sheppard, D. Jewitt and J. Kleyna (2006). A Survey for Normal Irregular Satellites of Neptune: Limits to Completeness. Astronomical Journal, 132, 171-176. pdf version

    We did the same for Neptune (limiting red magnitude 25.8).

  7. D. Jewitt, S. Sheppard and J. Kleyna (2006). The Strangest Satellites in the Solar System. Scientific American, August 2006 issue. pdf version

    This is a popular level review of the irregular satellites - the first ever written and so certainly the best!

  8. A radio piece (for those having incredibly short attention spans) is linked here, from Earth and Sky. [This is an mp3 file - will play within Quicktime or iTunes]. And if, like me, you find Block and Byrd and their background music peculiarly irritating, be sure to turn the sound off while you listen.

  9. D. Jewitt and N. Haghighipour (2007). Irregular Satellites of the Planets: Products of Capture in the Early Solar System. Annual Reviews of Astronomy and Astrophysics, 45, 261-295. pdf version

    This is written as a kind of intro to the subject and its scientific context for a general science audience. Again, the first of its kind, simply because this is a newly topical field with a lot of recent developments that could not have previously been written about.

Irregular Satellites Page