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Mark Showalter

Mark Showalter

Planetary astronomer Mark Showalter studies the dynamics of rings and small moons in the Solar System. Known for his persistence in planetary image analysis, Mark's early work with Voyager data led to the discoveries of Jupiter's faint, outer "gossamer" rings and Saturn's tiny ring-moon, Pan. His work with the Hubble Space Telescope starting in 2003 has led to the discoveries of "Mab" and "Cupid," small moons of Uranus now named after characters from Shakespeare's plays. His work also revealed two faint outer rings of dust encircling the planet. In 2011, Mark initiated a Hubble observing program focused on Pluto, which has led to the discoveries of two tiny moons. Their names, "Kerberos" and "Styx", were selected through an international naming campaign. Most recently, Mark discovered the 14 known moon of Neptune, which is designated "S/2004 N 1" until its permanent name can be selected. He is a co-investigator on NASA's Cassini mission to Saturn and its New Horizons mission to Pluto.

Latest Planetary Radio Appearance

Mark Showalter: Unraveling the Mysteries of Planetary Rings

10/22/2007 | 0:28:52

Mark Showalter: Unraveling the Mysteries of Planetary Rings

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Latest Blog Posts

Telling Pluto’s Story, One Fragment at a Time

Posted 2015/06/11 04:29 CDT | 2 comments

Mark Showalter explains how determining basic information about Pluto's small moons—Kerberos and Styx—is more complicated than initially thought.

The Mapping of Pluto Begins Today

Posted 2015/03/20 12:12 CDT | 7 comments

When New Horizons flies past Pluto in July, we will see a new, alien landscape in stark detail. At that point, we will have a lot to talk about. The only way we can talk about it is if those features, whatever they turn out to be, have names.

Older blog posts »

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