Citation

Shaunna Morrison is an amazing scientist who has made groundbreaking contributions among her 4-score publications. She has garnered an exceptional international reputation, both in conducting unprecedented studies on Mars and in applying data-driven discovery to rocks and minerals on Earth and other worlds. Morrison’s earliest breakthroughs relate to studies of Mars mineralogy. A key member of the CheMin team (the X-ray diffractometer on Curiosity), she realized that Mars’s minerals could serve as internal X-ray standards and developed algorithms that increased the precision and accuracy of CheMin data by an order of magnitude better than flight specifications. In 2017 Morrison began to focus on planetary informatics. Leading a team of collaborators in mineralogy and data science, her first informatics paper focused on applications of network analysis to mineral systems. Shaunna’s breakthrough was to realize that networks of mineral associations facilitate analysis and visualization of mineral systems in dynamic, interactive renderings—a fresh approach to a centuries-old science. She is also building mineral databases for planets, moons, and meteorites to compare their properties using network metrics—an approach that suggests that mineral distributions may be a biosignature. Morrison is helping to develop a new “evolutionary system” of mineralogy, which adds the dimension of time to mineral classification. Recently, Morrison has been pioneering applications “association analysis,” using machine learning methods to predict as yet undiscovered localities of minerals, as well as Mars analogue sites on Earth. Several predictions have been confirmed, pointing to a promising new approach to resource discovery and interpretation. These advances have not gone unnoticed. She is a Mineralogical Society of America Distinguished Lecturer and delivers dozens of seminars, public lectures, and keynote and plenary conference lectures annually. She is active in organizing data science workshops and conferences, and she and her education colleagues won a national 4-H Club competition to develop an outreach program on Mars exploration and mineralogy—an effort that is reaching tens of thousands of children. Among Morrison’s most impressive traits is her desire to reach across disciplinary boundaries, to seek out scientists with expertise different from her own. As a member of NASA’s Astrobiology Institute, she is integrating seemingly disparate fields of proteomics, microbial ecology, geochemistry, and mineralogy to deduce how environmental characteristics play key roles in microbial protein expression. Her ability to work with and inspire others will play a vital role in her growing influence and her rise to the highest levels of the scientific world.

—Robert M. Hazen, Earth and Planets Laboratory, Carnegie Institution, Washington, D.C.

Response

I am deeply honored to receive the Ronald Greeley Early Career Award in Planetary Sciences, and I extend my sincere gratitude to the selection committee. This recognition underscores the incredible mentorship, support, and collaboration I have been privileged to experience throughout my career. I wish to express my heartfelt thanks to those mentors and colleagues who have played transformative roles in my science and in my life. I would like to thank my undergraduate mentors, Thomas Weiland, Samuel Peavy, and Burchard Carter, for fostering my love of geology. I am deeply grateful to my M.S. and Ph.D. adviser, Robert Downs, for showing me how to be a scientist; for teaching that hard work, creativity, and excitement are paramount in doing cutting-edge science; and for enabling me to join the NASA Mars Science Laboratory’s CheMin team. The CheMin team, including David Blake, David Vaniman, Richard Morris, Doug Ming, Elizabeth Rampe, Thomas Bristow, Allan Treiman, and Cherie Achilles, holds my utmost gratitude for setting the gold standard of team dynamics and resilience in the face of challenges. I am profoundly grateful to Robert Hazen, whose expansive view of mineralogy and its role in Earth’s evolution broadened my scientific perspective—our work together has been among the most exciting and fulfilling of my career, and his unwavering support has been instrumental in my personal and professional growth. I would like to thank Peter Fox and Ahmed Eleish, whose willingness to share their expertise in data science empowered me to explore new frontiers with data-driven discovery and mineral informatics. My close collaborator, Anirudh Prabhu, is a pioneer of mineral informatics—I am so grateful for his readiness to discuss ideas and questions for hours on end, his visionary perspective, and his willingness to cross discipline boundaries to transform Earth and planetary sciences. My appreciation extends to my colleagues from scientific domains different from my own, including Mike Wong, Donato Giovannelli, Alexandra Ostroverkhova, Nathan Yee, Paul Falkowski, and James Wright, who broaden my ideas and push my scientific boundaries. I am grateful for the monumental efforts of Kerstin Lehnert, Marshall Ma, Jolyon Ralph, and their teams—their pioneering work in data stewardship makes data-driven discovery in mineralogy and geochemistry possible. Last, I acknowledge the Carnegie Institution for Science’s support of my research over the past 5 years, with special thanks to Michael Walter and Eric Isaacs for their belief in this new direction of science.

—Shaunna Morrison, Carnegie Institution, Washington, D.C.

Citation

Mackenzie Day received her B.S. from the California Institute of Technology in 2012 and her Ph.D. from the University of Texas at Austin in 2017. Mackenzie is now an assistant professor at the University of California, Los Angeles, and she is a leader at interpreting modern and ancient planetary surface systems affected by windblown sediment. Her scientific advances are built on a deep understanding of aeolian processes that is creatively applied to estimate environmental properties encoded in landforms and sedimentary deposits. Mackenzie’s careful work has demonstrated that the structure of simple dune fields and their constituent dunes are truly reflections of their formative wind regimes and sediment supplies. This has provided foundational support for Earth analogue studies and confirmed that surface conditions on planetary bodies can be accurately estimated using appropriate morphodynamic frameworks. Focusing on craters as a primary source and sink for dune sediment, her research group defined the critical crater wall slope connected to whether sediment eroded from intracrater deposits can be transported out of a crater basin and thereby be transferred to the regional sediment budget. Mackenzie’s expertise in modern aeolian systems has also benefited mission operations, including how different types of windblown deposits affect rover trafficability and identification of sites of active bedrock erosion that likely make optimal sampling locations for ancient Martian biosignatures. Mackenzie has also made significant contributions to our understanding of the early Martian environment via innovative stratigraphic analyses. These studies have helped define ancient wind fields and properties of the wet-to-dry Mars transition preserved in fluviolacustrine to aeolian sedimentary successions. Evaluating limitations in the spatial resolution of Mars imaging has allowed Mackenzie to demonstrate that many layered deposits are likely aeolianites. Working across scales, Mackenzie has contributed to a better definition of subthreshold grain saltation at particle dimensions, and a better definition of erosive, rim-generated vortices at the crater scale. Sediment transported by these vortices is commonly worked into dunes that interact with each other as they migrate and grow. Mackenzie has made fundamental contributions to understanding these dune interactions, as well as the sedimentary structures they generate. Following Ronald Greeley, Mackenzie’s considerable scientific contributions are matched by her professional services that include the training and mentoring of junior planetary scientists. Mackenzie Day has earned the Ronald Greeley Early Career Award for “innovative application of theory, field and remotely sensed data to the erosion and deposition of planetary landforms by windblown sediment.” —David Mohrig, University of Texas at Austin

Response

I feel truly honored to receive the Ronald Greeley Early Career Award in Planetary Sciences. I never had the privilege of meeting Ron Greeley during his lifetime, but I have certainly learned from him through his work. His contributions to aeolian geology in particular have been at the foundation of much of my research, and I hope my career will reflect his legacy of research and mentorship. I want to thank the many people who have mentored and supported me over the years, from John Grotzinger, who gave me my first research job as an undergraduate, to David Catling, who gave me the flexibility to explore new ideas as a postdoc. I am grateful for the community of mentors and colleagues I had during my time in Texas, including David Mohrig, Ryan Ewing, and Tim Goudge, and for the wonderful colleagues who welcomed me to my new department at University of California, Los Angeles. I am especially grateful for the support of my graduate adviser, Gary Kocurek, whose patient mentorship and guidance taught me not only how to see the puzzle in the landscape but also how to solve it. I also want to thank my students and collaborators. Their effort has contributed immensely to my career and cannot be understated. I have been incredibly fortunate to be supported and welcomed by so many people, and I hope to honor that support and Ron Greeley’s legacy by paying it forward as a supportive mentor myself. —Mackenzie Day, University of California, Los Angeles

Xi Zhang received the 2019 Ronald Greeley Early Career Award in Planetary Sciences at AGU’s Fall Meeting 2019, held 9–13 December in San Francisco, Calif. The award recognizes “significant early career contributions to planetary science.”

 

Citation

Xi Zhang received his Ph.D. in planetary sciences from California Institute of Technology in 2013. He is one of the few scientists whose research covers many subfields in planetary atmospheres, including remote sensing, fluid dynamics, chemistry, haze and cloud formation, and radiative transfer. Xi’s work revolutionized our understanding of the roles of aerosols in planetary atmospheres in many aspects. Xi’s proposal on the feedback of sulfur aerosols on gas chemistry is the leading theory to explain Venus Express’s observations of sulfur oxides. From Cassini data, Xi derived maps of temperature, chemical species, and aerosols in Jupiter’s stratosphere and identified the role of aerosols in the energy budget on Jupiter. Xi proposed an explanation for the unexpected cold atmosphere of Pluto observed by the New Horizons mission. He found out that hazes in Pluto’s atmosphere, instead of gases, dominate the radiative cooling as well as the heating. This discovery led to a paradigm shift in our understanding of the atmospheric energy balance of the new “cold and hazy” regime that also includes Neptune’s moon Triton and Saturn’s moon Titan. Xi’s work has implications for the haze and cloud formation on exoplanets and its impact on observed spectra and planetary evolution of low-mass planets, as well as on developing the next-generation three-dimensional general circulation models of the cloudy atmospheres on giant planets, exoplanets, and brown dwarfs. His contributions overall have been both wide and deep, revolutionizing our understanding of planetary climate.

—Yuk Yung, California Institute of Technology, Pasadena

Response

I am deeply honored to be the recipient of the Ronald Greeley Early Career Award this year. I thank the award committee for this recognition. Just like Ron, I enjoy working in many diverse fields. I hope my research will be as wide and as deep as his is.

I would like to thank my nominator and Ph.D. advisor, Yuk Yung, for his continuous support and important guidance from his deep thoughts on Eastern and Western cultures. I would also like to thank my postdoc advisor, Adam Showman, who is not only a mentor but also a good friend. Thanks to all the colleagues and collaborators who have supported and encouraged me in these years, especially Mark Allen, Bob West, Darrell Strobel, and Julie Moses. I would like to thank my undergraduate advisor, Zuo Xiao, at Peking University for his tremendous help in my early career. Thanks to my undergrads, Ph.D. students, postdocs, and visiting scholars at University of California, Santa Cruz. Finally, I would also like to take this opportunity to acknowledge all the support from my friends and my family. In particular, I dedicate this great honor to my wife, Yunwen Duan, for her unwavering love, support, and belief in me. I owe her everything.

—Xi Zhang, University of California, Santa Cruz

Brandon Johnson will receive the 2018 Ronald Greeley Early Career Award in Planetary Sciences at AGU’s Fall Meeting 2018, to be held 10–14 December in Washington, D. C. The award recognizes “significant early career contributions to planetary science.”

 

Citation

The Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley Award winner is Brandon Johnson, an assistant professor at Brown University.

Brandon received his Ph.D. in physics from Purdue University in 2013 for fundamental work on the mechanisms by which impact spherules and melt droplets form in large cratering events. His work linked the size of ancient spherules to the size and velocity of the projectile that created them. He demonstrated that the impactor flux was much higher in the Archean than it is today.

Although his core area of expertise is impact cratering, Brandon has addressed a range of fundamental problems in planetary science. He revived the controversial idea of an impact origin of chondrules by developing models for impact jetting onto the surfaces of protoplanets. As the jetting model was debated among meteoriticists, Brandon linked CB chondrules to the high-energy impacts generated by Jupiter’s growth and migration. This work highlights Brandon’s talent in combining collision physics with planetary observations in the broader context of planet formation.

Brandon has also provided new insight into the physical properties of the Sputnik Planitia basin on Pluto. He showed that the positive gravity anomaly required the presence of a subsurface ocean, placing a key thermal constraint on the history of Pluto. With important contributions spanning the mechanics of impact basin formation to tectonics on icy satellites, Brandon’s work has consistently reframed our views on important planetary processes.

AGU congratulates Brandon Johnson for his diverse and creative contributions to planetary science.

—Sarah T. Stewart, University of California, Davis

Response

I am honored to be named the 2018 recipient of the Ronald Greeley Early Career Award in Planetary Sciences. This award is truly a source of encouragement and validation for the research that I love. I thank those who nominated me for this honor, Sarah Stewart for writing the citation, and the award committee for this recognition.

I would like to acknowledge all the people who have supported me throughout the formative years of my career. I am especially indebted to my Ph.D. advisor, Jay Melosh, for his continuous support. Just 8 years ago I was working in a condensed matter physics lab, unhappy, contemplating leaving graduate school, and looking for other opportunities. After a serendipitous meeting, Jay introduced me to the study of impact cratering and kindled my passion for planetary science. In addition, I thank my amazing postdoctoral advisor, Maria Zuber, who sparked my enthusiasm by encouraging me to pursue the research that I was most excited about; my undergraduate advisor, Ranjit Pati, for having confidence in my potential and encouraging me to apply to graduate school; and the many unofficial advisors who have generously offered their expertise and guidance along the way. I am also grateful to all of my colleagues and collaborators who have shared and continue to share in the excitement of discovery with me.

Last, but certainly not least, I thank Alexandria, my wife and fellow scientist. I owe any success I have to Alexandria and her unwavering support.

—Brandon C. Johnson, Brown University, Providence, R.I.

Seth A. Jacobson will receive the 2017 Ronald Greeley Early Career Award in Planetary Science at the 2017 American Geophysical Union Fall Meeting, to be held 11–15 December in New Orleans, La. The award recognizes “significant early career contributions to planetary science.”

 

Citation

The Ronald Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley award winner is Seth Jacobson, an assistant professor at Northwestern University.

Seth received his Ph.D. in astrophysical and planetary sciences from the University of Colorado Boulder in 2012 for work in asteroid dynamics including the evolution and formation of binary asteroids. His work on rotational fission of small bodies explains many of the observed dynamical properties and classes of near-Earth asteroids.

In his postdoctoral work at Nice Observatory, Seth has focused on major problems in terrestrial planet formation. By combining N-body simulations and geochemical and geophysical observations, Seth has made important contributions to our general understanding of the formation of the inner solar system and the Earth–Moon system. By combining observations of siderophile elements in Earth’s mantle with planet accretion models, Seth proposed a “cosmic clock” that relates the timescale for planet growth to the amount of residual primitive material and used it to constrain the age of the Moon-forming giant impact. Seth’s work on understanding rocky planet accretion and differentiation as concurrent processes sheds light on the differences between Venus and Earth, including Venus’s lack of a magnetic field.

In the words of a senior colleague, Seth is a “volcano of ideas.” Seth’s dynamism, curiosity, and creativity have established him as a young leader in planet formation research. The planetary science community congratulates Seth Jacobson for his outstanding early-career achievements.

—Sarah T. Stewart, University of California, Davis

Response

It’s an honor to be selected by the Planetary Sciences section of AGU for the Ronald Greeley Early Career Award. I appreciate the recognition from the awarding committee and those who nominated me. One of the most influential undergraduate courses in my career was built around Ron’s book Planetary Surfaces and a field trip to look at terrestrial analogues in northern Arizona.

Throughout my education and my nascent career, the planetary science community has always been welcoming and encouraging to me. From far above Cayuga’s waters to the Flatirons, the Côte d’Azur, and now the shores of Lake Michigan, I have found inspiring colleagues willing to share their success with me, as well as lasting friendships. Particularly, I am thankful to planetary science for introducing me to Patrick, Catherine, Briony, Jay, Toshi, Christine, Robbie, Paul, Erik, Matija, Aurélien, Bert, Josef, Michiel, Federica, and Steve. I am also especially grateful to my advisors over the years: Jean-Luc, Dan, Dave, and Morby, as well as our colleagues at Cornell, Colorado, Bayreuth, and Nice Observatory.

I would like to dedicate this award to my wife, who always impresses me by her ability to find success in adversity and face changes bravely. I am also grateful to my family for their support of my career.

As I advance in my career, I plan to honor Ron’s legacy with a commitment to mentorship and service to the planetary science community. I will work to make the field of planetary science as welcoming and encouraging to everyone as it has been to me.

—Seth A. Jacobson, Northwestern University, Evanston, Ill.

Edwin Kite will receive the 2016 Ronald Greeley Early Career Award in Planetary Science at the 2016 American Geophysical Union Fall Meeting, to be held 12–16 December in San Francisco, Calif. The award recognizes significant early-career contributions to planetary science.

 

Citation

The Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley Award winner is Edwin Kite, an assistant professor at the University of Chicago. Edwin received his Ph.D. from the University of California, Berkeley in 2011.

Edwin’s research topics focus on the roots of planetary habitability, from the deepest crevasses on Enceladus to the farthest Earth-like exoplanets. Edwin’s research style is in a category of its own. He uniquely blends geological and geophysical tools to uniquely tackle the question at hand.

Edwin has applied models of atmospheric breakup of meteoroids to estimate the ancient atmospheric pressure on Mars. By using the record of small impact craters on ancient river valleys, he found an upper limit of about 0.9 bars. With such a low atmospheric pressure, a CO2 greenhouse would not be able to support stable liquid water on the surface. This novel study is a critical contribution to the debate over a cold, wet or warm, wet early Mars.

Edwin’s studies of the geysers on Saturn’s tiny moon Enceladus have explained how tides can maintain water-filled fissures in connection with the subsurface ocean. The eruptions provide direct access to material from the subsurface ocean. His work finds that the eruptions can be sustained for millions of years.

Edwin’s curiosity and creativity are boundless. He infects his collaborators and colleagues with the joy of chasing fresh ideas and finding the unexpected.

The planetary science community congratulates Edwin for his many early-career achievements.

—Sarah T. Stewart, University of California, Davis

Response

I am honored and encouraged by this award. I’d like to thank my thesis advisor, Michael Manga, and all of the other people who have helped me through mentorship and by being excellent role models: in particular, Eugene Chiang, Heather Knutson, Bill Dietrich, and Frederik Simons. I’d like to thank my officemates, fellow grad students, and collaborators—especially Eric Gaidos, Mike Lamb, and Allan Rubin—for providing constant intellectual stimulation. One of the things that makes planetary geoscience fun is that we need to go after problems with both a historical, forensic approach—what happened here and why? —and also a physicist’s approach—how can this system teach us about general principles? This can be hard! Fortunately, the literature is well stocked with examples of how to do both, and I’m grateful to all those senior scientists whose papers (like the work of Ron Greeley) serve as an example, a spur, and a helping hand to early-career people. You know who you are! Now that I’m happily ensconced at the University of Chicago, I’m focused on the processes that sustain habitable planets. We don’t know the answer to the question—how many living planets are there currently? But I’m encouraged to think that in future the answer will be “as many as there can be.” Finally, I would like to thank my friends and family.

—Edwin Kite, University of Chicago, Chicago, Ill.

Ian Garrick-Bethell will receive the 2015 Ronald Greeley Early Career Award in Planetary Science at the 2015 American Geophysical Union Fall Meeting, to be held 14–18 December in San Francisco, Calif. The award recognizes significant early-career contributions to planetary science.

 

Citation

The Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize.

This year’s Greeley Award winner is Ian Garrick-Bethell, an assistant professor at the University of California, Santa Cruz. Ian received his Ph.D. from the Massachusetts Institute of Technology in 2009, working with Maria Zuber and doing a second project with Ben Weiss, and moved afterward to a postdoc at Brown University.

Ian began by studying the long-wavelength topography and the inertial moments of the Moon. Ian first suggested that the Moon might not have spent its orbital evolution in a circular, synchronous orbit but may have moved through other orbital configurations, including a 3:2 spin orbit resonance. Ian went on to show that the Moon’s fossil shape is consistent with being a tidal-rotational bulge that formed when the Moon was at 32 Earth radii. Ian’s first lunar work was published in Science.

Ian then worked with Ben Weiss to use modern techniques to investigate the source of remanent magnetism in some lunar rocks. The resulting paper, also published in Science, provided the first convincing evidence of an ancient core dynamo on the Moon. Now, Ian is the principal investigator on a Discovery mission proposal to investigate the high-albedo swirls visible on the Moon’s surface, which he suggests are caused by locally strong crustal magnetic fields.

It’s often said that the difficult part of science is not finding answers, but asking the right questions. Ian has the gift of asking the big questions. Congratulations to Ian Garrick-Bethell, the 2015 recipient of the Ronald Greeley Early Career Award in Planetary Science.

—Linda T. Elkins-Tanton, Arizona State University, Tempe

Response

I am deeply honored to receive the Ronald Greeley Award this year. Ron’s interest in the Moon at the start of his career is particularly inspiring to me, as I have also started my career studying the Moon. Ron eventually contributed to the study of many solar system objects, and I hope my research may eventually have the same reach.

I would like to acknowledge the tremendous support I’ve had from my Ph.D. advisers, Maria Zuber and Benjamin Weiss. I am very grateful for their roles in my career. I’d also like to acknowledge and thank my outstanding postdoc advisers, Carle Pieters and Jim Head. Many thanks to the support from NASA Ames Research Center in developing mission concepts with me, especially with the assistance of Pete Worden and Belgacem Jaroux. I’d like to thank Bob Lin for his early enthusiasm for many of these concepts. I’d also like to acknowledge my Korean collaborators, who I have enjoyed working with enormously, particularly Ho Jin and Dong-Hun Lee. Also, I am deeply indebted to the work of my graduate and undergraduate students. Finally, I’d also like to acknowledge the essential support from my friends and family.

—Ian Garrick-Bethell, University of California, Santa Cruz

Catherine Neish received the 2014 Ronald Greeley Early Career Award in Planetary Science at the 2014 American Geophysical Union Fall Meeting, held 15–19 December in San Francisco, Calif. The award recognizes significant early career contributions to planetary science.

 

Citation

The Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. During his lifetime, Ron was involved in nearly every major planetary mission and was extraordinarily active in service to the community. Ron’s greatest legacies, however, are those he mentored, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley award winner is Catherine Neish, an assistant professor at the Florida Institute of Technology. Catherine received her Ph.D. from the University of Arizona in 2008 and, after a postdoctoral stint at NASA Goddard, joined the faculty at Melbourne in the Department of Physics and Space Sciences.

Catherine specializes in planetary surface properties, and she is ecumenical in choice of target, having written papers that incorporate data from eight different planetary bodies: Mercury, Venus, Earth, the Moon, Europa, Ganymede, Titan, and Triton. This certainly embraces the spirit of the Greeley award, as Ron was someone who was interested in the whole of planetary science, not just a single planetary body.

Catherine is expert in the use of orbital radar observations and has used these with optical imaging and topography to thoroughly revise our understanding of impact melt flows. She has also proposed that craters at high latitudes and low elevations on Titan are not simply buried by later sediments but form flattish to begin with, in a manner similar to craters formed on Earth in soft, oceanic sediments.

But not all of Catherine’s work is remote sensing based. Her Ph.D. thesis had three doctor-fathers: Ralph Lorenz, Jonathan Lunine, and Mark Smith. Her papers with them on the astrobiological potential of Titan and the lab work that went into them are notable. The relative ease in which biological molecules such as amino acids can form in ammonia-infused “Titan primordial soup” suggests (as if we needed reminding) that life may be ubiquitous in the universe. One suspects such work will have long-lasting impact.

Congratulations to Catherine D. Neish, the 2014 recipient of the Ronald Greeley Early Career Award in Planetary Science.

—William B. McKinnon, Washington University, Saint Louis, Mo.

Response

I have always greatly admired the curiosity that Ron Greeley showed for all the many wonders of the solar system. I work in many diverse fields, and every time I start a new project, I see Ron’s influence there. His willingness to study new processes on a range of planetary objects makes him the type of planetary scientist that I endeavor to be. I hope to continue to follow in his footsteps as I progress in my career and am deeply honored to receive this award that bears his name.

I would also like to take this opportunity to thank all of those who have supported me throughout my career. Science is not a solitary enterprise, and I have benefited greatly from the advice and wisdom of a great many people. Thanks to Ellen Howell and Mike Nolan for introducing me to planetary radar, a passion that has guided my career. Thanks to the entire community of graduate students, postdocs, and faculty at the Lunar and Planetary Laboratory for fostering my curiosity for planetary science. I would especially like to thank the incoming class of 2004 for their friendship and Ralph Lorenz, Jonathan Lunine, Mark Smith, and Árpád Somogyi for guiding my Ph.D. research. Thanks also to my colleagues at the Applied Physics Laboratory and Goddard Space Flight Center for helping an inexperienced postdoc transform into a confident scientist. Finally, I would like to thank my parents for their unwavering support and my husband, Shawn, for constantly pushing me to be my best. I share this award with them.

—Catherine Neish, Florida Institute of Technology, Melbourne

Jonathan L. Mitchell received the 2013 Ronald Greeley Early Career Award in Planetary Science at the 2013 AGU Fall Meeting, held 9–13 December in San Francisco, Calif. The award recognizes significant early-career contributions to planetary science.

 

Citation

The Greeley Early Career Award is named for pioneering planetary scientist Ronald Greeley. Ron was involved in nearly every major planetary mission from the 1970s until his death and was extraordinarily active in service to the planetary science community. Ron’s greatest legacies, however, are those he mentored through the decades, and it is young scientists whose work and promise we seek to recognize. This year’s Greeley award winner is Jonathan L. Mitchell, an assistant professor at the University of California, Los Angeles (UCLA). Jonathan received his Ph.D. from the University of Chicago, and after a postdoc at the Institute for Advanced Studies in Princeton, he joined the UCLA faculty, where he holds a joint appointment in Earth and space sciences and in atmospheric sciences.

Jonathan is one of the few planetary scientists, young or old, who is also a recognized expert in geophysical fluid dynamics and the fundamental theory of atmospheric circulation as it has been developed in the terrestrial community over the past half century. This places Jonathan in a rather unique position to understand the dynamical processes occurring in planetary atmospheres. Jonathan has already made major contributions to our understanding of Titan’s atmosphere, the existence of equatorial superrotation in planetary atmospheres generally, atmospheric thermodynamics, and the atmospheric and interior dynamics of hot giant exoplanets.

As an example, Jonathan’s detailed three-dimensional circulation models for Titan have explained how equatorial and midlatitude cloud systems can lead to precipitation that greatly exceeds the time-averaged precipitation rates, up to perhaps several centimeters of liquid methane rain in individual events. Such rare but intense events must cause significant fluvial erosion, so Jonathan’s models help to explain the existence of widespread fluvial erosion features on Titan’s surface at low latitudes, which are otherwise relatively dry and lake free.

Jonathan’s adaptation of Earth-based knowledge to solve planetary problems and his judicious comparisons of physical mechanisms on different planets are what Ron Greeley would have termed comparative planetology and are very much in Ron’s style, as is Jonathan’s mentoring of his growing research group.

Congratulations to Jonathan L. Mitchell, the 2013 recipient of the Ronald Greeley Early Career Award in Planetary Science.

—WILLIAM B. MCKINNON, Washington University, St. Louis, Mo.

Response

I am honored to receive this award in memory of Ron Greeley. Although I did not have the opportunity to know him, I had the pleasure of getting to know his wife, Cynthia, at a luncheon prior to the special awards session at the AGU Fall Meeting. Cynthia is an intelligent and elegant southern woman with a confident gaze. She spoke fondly of Ron and of her sincere respect for his work ethic and dedication to planetary science. What most impressed me, though, was the respect Ron showed to her and the kids by always “giving them the evenings”; no matter how busy things got, Ron always kept his evenings open for Cynthia. This clearly meant the world to her. As a family man, I can only hope that my wife and kids will speak so kindly of me many years from now. I would like to dedicate this award to them in gratitude for their seemingly unconditional love and support.

I would also like to take this opportunity to thank the individuals who have positively influenced my career. I owe nearly all my inspiration to the Cassini team; many thanks to you all. My thanks to Ray Pierrehumbert for taking a chance on a disillusioned cosmologist when he agreed to be my thesis advisor. Working with Ray reminded me that science should be (and is) fun. Thanks also to Geoff Vallis and Peter Goldreich for their mentoring during my postdoc years and for their continued advocacy in my early career. Thanks to my anonymous senior colleagues who nominated me and to the selection committee for this great honor. And, finally, thanks to my parents who always encouraged me that I could do whatever I set my mind to.

—JONATHAN L. MITCHELL, University of California, Los Angeles

Alexander G. Hayes Jr. received the 2012 Ronald Greeley Early Career Award in Planetary Science at the 2012 AGU Fall Meeting, held 3–7 December in San Francisco, Calif. The award recognizes significant early-career contributions to planetary science.

 

Citation

The first Ronald Greeley Early Career Award in Planetary Science is presented to Alex Hayes, an assistant professor of astronomy at Cornell University. He received his Ph.D. from Caltech and did a postdoc at Berkeley. His record is impressive, and he is very well suited to be the first Greeley Award winner; he has a mix of science and engineering experience and training, leading to special insights into how to best optimize use of spacecraft data to make scientific breakthroughs. Among a group of highly qualified nominees for the first Greeley Award, Alex’s accomplishments clearly stood out—he has already coauthored more than 40 papers.

Alex uses spacecraft-based remote sensing to study the properties of planetary surfaces and their interactions with the interior and atmospheres, with a recent focus on Titan and Mars. Titan is the only planetary object besides Earth that supports standing bodies of liquid on its surface. Alex uses the Cassini Radar to study and model surface morphologies on icy satellites, including the distribution and evolution of Titan’s hydrocarbon lakes and seas. His first paper became a common reference for Titan’s northern lake distribution because Alex carefully and systematically mapped their distribution and classified them into types that have now become standard. He is also interested in studying the depositional and diagenetic history of early Mars, leveraging data from the Mars Exploration rovers and Mars Reconnaissance Orbiter.

But in fact, the best words I can use to describe Alex come from his nominators. Here is just a taste of what they had to say:
“Alex is unquestionably one of the most exciting new planetary science Ph.D.s in the world. He is particularly prominent in ­mission-­related science (as was Ron Greeley), notably the lakes and morphology of Titan. From personal experience, I can say that Alex is unusually interactive, insightful, and engaged on just about any issue having to do with planetary geology, especially morphology.”

“He has an unquenchable curiosity, performs to the highest standards that one can expect, and will unquestionably emerge as one of most influential planetary scientists of his generation. While his natural abilities are all very strong, perhaps his most notable attribute is his tenacious drive to learn.”

“In addition to Alex’s accomplishments, I think he is a particularly appropriate candidate for the first Greeley award because of some surprising similarities between them…Like Ron, Alex started out working on Mars. Later, Ron considered wind speeds necessary to lift grains on Mars; Alex considered winds necessary to raise waves on Titan. Both studied dunes. Both used radar to probe planetary surfaces. Both wrote about icy satellites. Comparing their early careers, they were both astonishingly productive.”
Congratulations to the winner of the first Ronald Greeley Early Career Award in Planetary Science, Alex Hayes.

—LAURIE A. LESHIN, Rensselaer Polytechnic Institute, Loudonville, N. Y.

Response

I am deeply honored to be the inaugural recipient of the Ronald Greeley Early Career Award. Ron was an icon in the field of planetary science, and the establishment of this award is a fitting way to pay tribute to his legacy. I applaud Laurie Leshin, Bill Mc­Kinnon, and the rest of the AGU Planetary Science section officers and selection committee for taking the time to organize this memorial. Ron is remembered not only for his fundamental scientific contributions but also for his mentorship and support of early-career scientists, both his own students and postdocs and those of his colleagues.

Though I never worked with Ron directly, he always took the time, whether we met at a conference or a Viennese concert, to stop what he was doing and ask me how things were going. It is in the same spirit that I would like to thank my mentors and colleagues who have provided the opportunities that I have been able to take advantage of. This includes my undergraduate advisors Steve Squyres and Jim Bell, who continue to support me to this day, as well as the entire Mars Exploration rover science team, notably including Ken Herkenhoff, Phil Christensen, and John Grotzinger.

I must also extend my most heartfelt gratitude to the Cassini Radar Science Team and Charles Elachi for not only developing a world-class instrument but welcoming me into their family and actually letting me use it from time to time. Most important, however, I must acknowledge my nominator and graduate advisor Oded Aharonson, who I count not only as a mentor but also as a friend. This memorial award is about these people and the connections we all enjoy in this community. Thank you.

—ALEXANDER G. HAYES JR., Cornell University, Ithaca, N. Y.