Adopt a Scientist: Lord of the Rings
Mark Showalter is an avid scuba diver, and has dived everywhere from Alaska to Australia, the Galapagos Islands, the Red Sea, and throughout the Caribbean and South Pacific.
Credit: Mark Showalter

SETI Institute planetary astronomer Mark Showalter is rabid about rings.

Showalter directs the Planetary Rings Node of NASA's Planetary Data System. Anyone looking for information on planetary rings comes to Showalter's website here at the SETI Institute. Mark manages the rings node and continues to pursue his research interests from the ground and in space.

While everyone knows about Saturn's spectacular ring system, it's often forgotten that Jupiter, Uranus, and Neptune are also encircled by fainter and narrower rings. Each of these systems interacts closely with a family of small, inner moons. Showalter works on some of NASA's highest-profile missions to the outer planets, including Cassini, now orbiting Saturn, and New Horizons, which recently flew past Jupiter en route to its 2015 encounter with Pluto. Known for his persistence in planetary image analysis, Mark's work on the earlier Voyager missions led to his discovery of Jupiter's faint, outer "gossamer" rings and Saturn's tiny ring-moon, Pan.

Mark splits his observing time between NASA space probes and Earth-based telescopes. He has been a frequent investigator with the Hubble Space Telescope. Since 2002, he has been leading a team of astronomers studying the planet Uranus. His discovery of two small moons — Cupid and Mab — and two additional faint rings orbiting that distant planet received national attention in 2006.

On the ground, Mark observes with the 10-meter Keck Telescope in Hawaii, where the new adaptive optics system has begun to rival and sometimes surpass Hubble in the clarity of its images. He will soon be turning his attention farther outward to Neptune, which is encircled by a peculiar family of rings, moons and incomplete arcs. These were studied by the Voyager spacecraft in 1989, but have been observed only a few times since then. Rings and the faint moons that interact with them are more than just local anomalies. They serve as dynamic laboratories where we can observe some of the same processes that operate, albeit on much larger scales, in galaxies and during the formation of planetary systems.

Adopt a Scientist: Mark Showalter

The best part of Mark's job is that he can come to work in the morning not knowing what new discovery might be awaiting him in the latest data.

He welcomes the opportunity to share this spirit of discovery with interested individuals or small groups. Watch over his shoulder as he processes the latest data and be among the first to see features that have never before been revealed to human eyes.

Mark isn't just rabid about rings. As an avid scuba diver, amateur naturalist and award-winning photographer, he spends his vacations exploring the diversity of life on Earth in its most distant and exotic and underwater environments. He has dived everywhere from Alaska to Australia, the Galapagos Islands, the Red Sea, and throughout the Caribbean and South Pacific.

As a different kind of journey of discovery, we invite experienced scuba divers on an expedition to a destination of their choice. Work with Mark to understand more about environments and life forms as we prepare for the trip, and then compare notes after each dive. Such a trip would also afford ample "down time" to explore Mark's other passion, photography, so we can examine the latest images from the heavens above when we're not focused on the oceans below.

The SETI Institute's Adopt a Scientist Program

Anyone can adopt a SETI Institute scientist and become part of the adventure!

Each of our scientists offers a compelling journey of discovery. When you adopt a scientist, you help lead the way towards answering profound questions regarding our place in the universe. You can form a one-on-one relationship and participate in the process of ground-breaking science with any number of our institute's scientists. In an effort to ensure that this vital research continues to prosper, our Adopt a Scientist Program invites you to make a direct contribution to the field.

There are many levels of commitment. For more information on the Adopt a Scientist program or to adopt a scientist, visit our website at . Or email Karen Randall at or call 650-960-4537.

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