|Results from Our Irregular Satellite Survey|
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.
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.
We surveyed Mars for irregular satellites. None were expected and none were found. Still, you never know until you've looked.
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.
We took advantage of unusually fine seeing and the fantastic Subaru telescope to survey Uranus to great depth (red magnitude 26.1).
We did the same for Neptune (limiting red magnitude 25.8).
This is a popular level review of the irregular satellites - the first ever written and so certainly the best!
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.