Outer planet Jupiter has probably more moons than have been counted so far. The greater majority of these satellites of Jupiter orbit in retrograde relative to the rotation direction of the planet. Satellites of any planet that orbit their ‘parent’ planet in retrograde are called irregular satellites to distinguish them from satellites that formed with the planet, and consequently would orbit in the same direction as the planet’s rotation.
Two recently discovered satellites, bringing the known or at least suspected number to 69, are described via their respective URL with a very official looking but somewhat confusing at first glance bulletin. The links are to the MPEC (Minor Planet Electronic Circular) at the Minor Planet Center.
Both of these satellites were discovered or co-discovered by Astronomers Scott Sheppard, David Tholen, and Chadwick Trujillo. Given the small size and challenges in imaging these satellites it is amazing that they were discovered. Read more about the discoveries at Sky & Telescope‘s web site.
MPEC 2017-L47 : S/2017 J 1 click here
MPEC 2017-L08 : S/2016 J 1 click here
Take a tour around Jupiter and its many satellites. The sizes of the Galilean satellites, Io, Europa, Ganymede, and Callisto have been made larger than they would actually be given the size Jupiter used in the video.