Tag: Obituary

Michael J.S. Belton was the President of Belton Space Exploration Initiatives, LLC, and an Emeritus Astronomer at the National Optical Astronomy Observatory (NOAO). Born in Bognor Regis, England, he received his Bachelor’s degree at the University of St. Andrews in Scotland, and earned his Ph.D. at the University of California, Berkeley. He joined Kitt Peak National Observatory (the precursor to NOAO) in 1964 and carried out research on nearly all objects that fell under “planetary science.” 

Belton was a member of the Mariner 10 team that flew a space probe by Mercury and Venus. As a member of the Mariner Jupiter/Uranus Science Advisory Committee he helped define what became the Voyager missions to the outer solar system. He was the Leader of the Galileo Mission Imaging Science Team. Galileo studied the Earth’s Moon, made the first close-up observations of an asteroid, Gaspra, and discovered the first moon of an asteroid, Dactyl, as it passed the asteroid Ida on its way to Jupiter. Before arriving, the team observed the impact of the fragments of comet Shoemaker-Levy 9 into the Jupiter atmosphere and later studied the aftermath in detail. At Jupiter, Belton and his team delved into the nature of the Galilean satellites, the population of small satellites, the Jovian ring system, and the planet’s atmosphere.

He was particularly interested in the origin and evolution of planetary systems, the physics of planetary atmospheres, high-resolution ground-based spectroscopy, and had a special affinity for comets. He studied them from ground-based and space-based telescopes and missions. His contributions were focused on understanding the mechanisms of cometary outbursts, determination of rotational states, exploring the interiors of cometary nuclei, how cometary activity can be used to probe the nucleus, and the size-distribution of comets. He was Deputy Principal Investigator of the Deep Impact mission to P/Tempel 1, a Co-investigator on the EPOXI mission to P/Hartley 2, and a Co-Investigator on the Stardust NExT mission that returned to P/Tempel 1. Belton was also a leader of the planetary science community, most notably chairing the first National Research Council Decadal Survey of Solar System Exploration.

For his contributions to the exploration of the solar system, in 1991 an asteroid was designated 3498 Belton by the International Astronomical Union and in 1995 the Division for Planetary Sciences of the American Astronomical Society awarded him the Gerard P. Kuiper Prize.  In 2000, he founded Belton Space Exploration Initiatives, LLC.

Among the young astronomers who worked with him on his many projects Mike Belton was a mentor who unselfishly encouraged their professional growth. He was an engaging, interested and positive colleague. He was an out-of-the box thinker and visionary in the truest sense. He is deeply missed.

Predeceased by his wife, Helyn, Mike Belton leaves behind his daughter, Lise Myra Belton (John Prader), his son, Scott Alexander Belton, and 3 grandchildren:  Emily Prader, John Prader and Elizabeth Rose Prader. For the past 20 years he has been married to Anna Don whose family has embraced him as their father. This family includes Drs. Michael (Sandy) Don, Norman (Tricia) Don and Damon (Kacy) Don. The Don grandchildren he leaves are Lindsay, Kristin, Colin, Abby, Tony and Ben.

A memorial will be held 10:30 AM Saturday, June 30, 2018, at the University of Arizona, Kuiper Space Sciences Building, Room 308. Remembrances are welcome and may be sent to [email protected].

Von R. Eshleman died peacefully on September 22, 2017, five days after his 93rd birthday.  Although he began his career in radar astronomy, he is best known as a pioneer in the use of spacecraft radio signals for precise measurements in planetary exploration — specifically, the radio occultation method for profiling planetary atmospheres and ionospheres, which has now been “brought home” for monitoring Earth’s atmosphere using GPS satellites.

Von was the youngest of four boys born in Covington, Ohio, a farming community with a large population of Old German Baptist Brethren, from which his grandfather had broken away in the late 1800s.  He progressed rapidly through his early school years, then served as an electronics technician in the U.S. Navy during World War II (1943-46).  While stationed in Italy at the end of the war, he became intrigued by the possibility of bouncing radio signals from the lunar surface.  Although his own ship-based experiments were unsuccessful, this curiosity guided his professional life for the next 60 years.

He attended the General Motors Institute of Technology and Ohio State University before graduating with a bachelor’s degree in electrical engineering from George Washington University in 1949.  While at GWU, he met and married Patricia Middleton and they had the first of four children.  Recruited to graduate school at Stanford University by Fred Terman, he obtained an MS in 1950 and a Ph.D. in 1952.  His doctoral research, supervised by Mike Villard and Larry Manning, was on radio reflections from ionized meteor trails in the upper Earth’s atmosphere.

After serving five years as a member of Stanford’s Electrical Engineering research staff, Von was promoted to Assistant Professor in 1957, then Associate Professor, and finally full Professor in 1962.  With colleagues Allen Peterson and Ray Leadabrand, he founded the Stanford Center for Radar Astronomy in 1962, which oversaw two-way dual-frequency radio propagation experiments between Stanford’s 150-foot antenna (‘The Dish’) and Pioneers 6-9 in orbit around the Sun, measuring the density, velocity, and structure of the solar wind.

By the mid-1960s Eshleman’s team had refocused on planets and on the telecommunications signals normally used to transmit spacecraft images and other remotely acquired data.  The radio signals themselves are perturbed when a spacecraft flies behind a planet; by measuring the small changes in frequency, it is possible to determine the temperature and pressure profile of an occulting atmosphere (very similar to the results returned by a weather balloon) and the electron density of an ionosphere. The experiments were originally proposed for an ‘uplink’ geometry (transmission from Earth to the spacecraft), but only ‘downlink’ implementations were approved.  Nonetheless, graduate students Gunnar Fjeldbo and Len Tyler (among others) perfected the technique and were rewarded with the first profiles from Mars (cold and thin) and Venus (hot and dense) in 1965 and 1967, respectively.  Eshleman and his associates also demonstrated that properties of planetary surfaces could be derived from radio echoes reflected from the Moon and Mars.

Eshleman was not involved in Pioneer 10 and 11 radio occultation experiments at Jupiter until it became apparent that the radio results differed radically from  results obtained by other instruments.  Over several years, Von and others worked out the corrections needed for analysis when planets are oblate (as the gas giants are because of their rapid rotation).  The effects of turbulence and magnetic fields were incorporated by Bjarne Haugstad and Dave Hinson.  Von led the Radio Science Team through the very successful Voyager 1 and 2 planning, implementation, and Jupiter encounters, then handed off day-to-day operations to Tyler.

After Voyager, Eshleman focused on topics such as evolute flashes during deep radio occultations, stellar gravitational lenses and their effects on propagating radio waves, ring particle dynamics, absorption in planetary atmospheres (with students Paul Steffes and Tom Spilker), and retro-reflection from icy planetary surfaces.  Although not a member of the science team, he got to see the ultimate radio occultation experiment (an uplink implementation) when New Horizons passed Pluto and signals transmitted from Earth were perturbed by its barely detectable atmosphere.

Dozens of graduate students benefited from Von’s direct mentoring; but he was also an innovative classroom teacher.  He converted a mezzanine-level class on electromagnetics to a generalized “waves” class for a broader audience of Stanford graduate students — such as those interested in acoustics, seismology, and oceanography.  For advanced undergraduates, he developed a new class called “Planetary Exploration”, which was attractive to students with science, engineering, and mathematics skills but who were not majoring in astronomy.

Von maintained contacts with industry, serving as a consultant for North American Rockwell and Watkins-Johnson.  He advised the McGraw-Hill Book Company, the National Bureau of Standards, and (of course) the National Aeronautics and Space Administration.  He also served briefly as Deputy Director of the Office of Technology Policy and Space Affairs in the U.S. Department of State.  But he always returned to the skilled and productive use of electromagnetics to explore the universe — a task that his associates recall that he not only wanted to do, but to do well.

Richard Simpson and other colleagues

Nathan Bridges, a planetary research scientist at the Johns Hopkins University Applied Physics Laboratory (APL), died on April 26. He was 50 years old.

Bridges, who joined APL’s Planetary Exploration (SRE) Group in 2009, was a senior expert on the geology of Mars, remote sensing techniques, and the role of wind-driven processes in planetary erosion and sedimentation on Earth, Mars, and Titan, Saturn’s largest moon. Among his many important findings, Bridges discovered that wind is as important a geologic process on Mars as it is on Earth, despite the much lower density of the Martian atmosphere.

He was an integral part of multiple Mars missions and instrument teams: he served as a Co-Investigator on the High Resolution Imaging Science Experiment (HiRISE) instrument on the Mars Reconnaissance Orbiter, a Co-Investigator on the Mars Science Laboratory (Curiosity rover) ChemCam instrument, and a science teammember on two Mars-2020 rover instruments, SuperCam and the Mars EnvironmentalDynamics Analyzer.

Bridges was also an associate research professor in the Department of Earth and Planetary Sciences at Johns Hopkins University, where he taught a class and advised graduate students. Additionally, he took leadership roles in the international planetary science community. For example, he served as editor of the American Geophysical Union publication EOS, secretary of the AGU Planetary Science Section, guest editor of several special issues of the journal Icarus, and on numerous NASA panels and advisory committees.

Bridges developed research collaborations with colleagues from around the world. His work included field studies at dune fields on Earth, experiments in wind tunnels to simulate conditions on other planets, and analysis of data from spacecraft observations.

He earned a B.A. in geology from the University of Colorado in 1989, an M.S. in geology from Arizona State University in 1992, and a Ph.D. in geology from the University of Massachusetts in 1997. He spent twelve years at NASA’s Jet Propulsion Laboratory in Pasadena, California, before joining APL.

Bridges is survived by his wife Karen, daughter Sarah, and son Matthew.

A tribute to Bridges from the Planetary Society, of which he was a member since 1980, can be read here.

 

A Tribute to Michel Combes

Michel Combes passed away on March 9, following a week of hospitalization. As a former Director of the Paris Observatory DESPA Laboratory (which later became LESIA) and a former President of Paris Observatory, Michel has played a major role in the life of the laboratory, the Observatory, and, beyond, in the development of planetology and of astronomical instrumentation in France and internationally.

As a former student of the Institut d’Optique in Paris, Michel entered the Observatory in the early 1960s. In 1969, Michel was a major actor in the establishment of a planetology group at the Observatory, first hosted within the Department of Solar Physics and later within the Space Research Department (DESPA).

Mainly interested in optics, Michel was convinced that new projects in astronomy require instrumental innovation.  In 1973, he led a campaign in South Africa to observe the occultation of the star Beta Scorpio by Jupiter. This successful experiment made possible the retrieval of the thermal structure in the stratosphere of Jupiter. In parallel, Michel worked on the development of a Fourier Transform spectrometer operating in the thermal infrared, devoted to the spectral analysis of Jupiter. This instrument was flown on the Kuiper Airborne Observatory in 1973, and has been mounted several times on large ground-based telescopes.

In the 1980s, with Tobias Owen in the US and Vassili Moroz in Moscow, and in partnership with other laboratories, Michel developed the concept of a new instrument for analyzing the near-infrared emission of comets. This successful experiment, launched on the Soviet probes Vega 1 and Vega 2, has led to the first measurement of the temperature of a cometary nucleus, and the detection of several parent molecules outgassed from the nucleus.

In the mid-1980s, Michel became the Director of DESPA, and drove the laboratory toward participation in the ISOCAM camera of the Infrared Space Observatory (ISO) of ESA. In parallel, the planetology group got involved in space projects of planetary infrared sounding. This was the beginning of a series of infrared imaging spectrometers, conceived and developed at DESPA in partnership with Institut d’Astrophysique Spatiale in Orsay and several international laboratories. The first ones were devoted to the exploration of Mars, with ISM/PHOBOS and OMEGA/Mars-96 in partnership with Russia. These instruments inspired the imaging spectrometers of Cassini/Huygens, Rosetta and Venus Express.  

In 1991, Michel became the President of Paris Observatory. This duty allowed him to express all his human and international relationship qualities, based on his excellent knowledge of men and institutions.  As a President, Michel initiated a re-organization of the scientific departments of the Observatory.  This was the first step of a global restructuration of the scientific departments, which was completed later in the early 2000. In the meantime, Michel continued to follow the development of infrared space projects at DESPA, in particular in the domain of stellar photometry and planetology. After the failure of the Mars-96 spacecraft just after launch, both experiments were rebuilt and used in other contexts, the French CoRoT mission and, under IAS’ PIship, the OMEGA instrument aboard Mars Express. Later, in collaboration with other international partners, the VIRTIS-H instrument was flown on two other European missions, Rosetta and Venus Express. He was also strongly involved in the NASA-ESA Cassini/Huygens mission through participation as co-investigator in DISR/Huygens and team member on VIMS/Cassini until recently.

In 1999, after two mandates, Michel came back to DESPA, which later transformed into LESIA, and became involved in teaching activities regarding optics, and in the development of instrumental concepts. He also became more and more involved in outreach activities within the Service of Communication of the Observatory, as well as within the team working on History of Sciences.

Thanks to his strong personality, his acute sense of politics, his engagement toward society, his sense of organization and dialog, Michel Combes has played a major role in the field of planetology but also at the level of the Observatory and beyond. Michel was a leader with a strong sense of responsibility, respectful of his international collaborators. He had a very strong capability for bringing teams together – scientists, engineers, technicians, administrative employees – and to make them work together towards a common objective. He will be deeply missed by his friends and colleagues. 

Therese Encrenaz and Pierre Drossart

Akiva Bar-Nun, a leader in the field of cosmochemistry, died in Jerusalem, Israel on January 25, 2017. Akiva was born in 1939. After completing his doctorate in shock wave chemistry at the Hebrew University in Jerusalem in 1968, he did his postdoc at Cornell University, where he worked with the late Carl Sagan. This led to a lifelong interest in the origins of life. His formal entrance into the field of planetary science came with a 1975 paper predicting that thunderstorm shocks were the source of short-lived hydrocarbons in Jupiter’s atmosphere. This prediction was eventually confirmed by spacecraft observations. In 1976, after six years as lecturer at the Hebrew University, Akiva joined the faculty at Tel Aviv University. There he continued to explore the importance of shockwaves for the origins of life. In addition, he investigated the photochemical production of planetary aerosols. Later on, he set up his unique and world-famous laboratory, where he conducted pioneering studies of ices under conditions typical of comets. His investigations on trapping of volatiles by cometary ices and their subsequent release upon warming of the ice, revolutionized cometary research. Akiva’s expertise made him a valuable contributor to several international space projects, including the HASI experiment on the HUYGENS spacecraft that landed on Titan, as well as the ALICE and ROSINA instruments on the ROSETTA spacecraft. Akiva served as the Director General of the Israel Space Agency between 1989-1993, and then for another two years as its Vice Chairman. He was an excellent teacher and mentor, who inspired numerous students, and he played an important role in advancing the public understanding of science. Generations of young students have delighted in his book on the Solar System (New Worlds, published in 1984, in Hebrew). Akiva was also a good friend. He will be sorely missed.

 

Morris Podolak and Dina Prialnik
Submitted by Jonathan Lunine

Mark Allen, 67, died on October 22 of complications from ALS (Lou Gehrig’s Disease). Mark was born in New York City on September 29, 1949, graduated Summa Cum Laude and Phi Beta Kappa from Columbia College of Columbia University in New York City and received his PhD from Caltech, both in chemistry. He spent nearly all of his 37-year career at Caltech and JPL, where he was a principal scientist, developing chemical models to study the atmospheres of the earth, planets, comets, interstellar space, and exoplanets. Working with his then postdoctoral advisor Prof. Yuk Yung of Caltech,  Mark was the principal architect, builder, and keeper of the comprehensive chemical code KINETICS which has become of the best-known models for simulating chemical processes in planetary atmospheres.  Mark was a team member of the NASA Astrobiology Institute (NAI) Virtual Planet Lab, Principal Investigator for the “Titan as a Prebiotic System” node of the NAI, and was involved in a number of NASA and ESA missions and mission concepts. He is survived by his wife of 34 years, Emily Bergman; children Boh Allen, Philip Allen, and daughter-in-law, Andrea Allen; mother Lucille Allen; and sister, Barbara Peterson. His research continues in the work of his colleagues and former graduate students and postdocs. Donations in his memory may be made to Columbia College at Columbia University, or the California Institute of Technology.

Jonathan Lunine, Yuk Yung, Julianne Moses, Bonnie Buratti, and Glenn Orton

Ewen was a British-born astronomer specializing in lunar studies since 1951. During WWII he was part of the secret PLUTO project (Pipe Line Under The Ocean) to supply Allied vehicles in France with gasoline after the Normandy invasion. After meeting Gerard Kuiper at an IAU meeting in Dubline in 1955, he was invited to join the Lunar Project at Yerkes to produce a high-quality photographic atlas of the moon, and subsequently moved with Kuiper to Tucson, Arizona, where this project ultimately resulted in the establishment of the Lunar and Planetary Laboratory. He provided valuable input into the planning and operations of Apollo operations on the Moon. Ewen was much beloved by his colleagues and is remembered for his knowledge, friendliness and charm.

Rememberances:

http://tucson.com/news/local/ewen-whitaker-moon-mapper-dies/article_dd048c21-2438-5d3d-b3ab-f9414a5042bf.html

http://www.planetary.org/blogs/jason-davis/2016/20161021-remembering-ewen-whitaker.html

https://sservi.nasa.gov/articles/ewen-a-whitaker-1922-2016/

http://www.skyandtelescope.com/astronomy-news/remembering-ewen-whitaker-1922-2016/

https://en.wikipedia.org/wiki/Ewen_Whitaker

The Ukrainian scientific community is very sad to announce the passing of Professor Edgard G. Yanovitskij on 23 June 2016. Dr. Yanovitskij spent his entire professional life as a leading researcher at the Main Astronomical Observatory of the Ukrainian National Academy of Sciences in Kyiv. As a prominent member of the famous Soviet school of radiative transfer founded by Academicians Viktor Ambartsumian and Viktor Sobolev, he had devoted most of his exemplary career to the study of radiative energy transport in planetary atmospheres and analyses of spectrophotometric observations of planets. His most profound accomplishments include the general analysis of principles of invariance, the analytical theory of radiative transfer in vertically inhomogeneous atmospheres, and the development of extremely efficient and numerically accurate computer solvers of the radiative transfer equation. His seminal contributions were summarized in the monograph on “Light Scattering in Inhomogeneous Atmospheres” published by Springer. For many years, Dr. Yanovitskij served as an Editorial Board Member for the “Journal of Quantitative Spectroscopy and Radiative Transfer” and “Kinematics and Physics of Celestial Bodies.” His research accomplishments were celebrated by numerous professional awards, including the National Prize of Ukraine in Science and Technology. The relatives, colleagues, and friends of Professor Edgard Yanovitsky will always remember him as an outstanding scientist and an exceptional human being.

Gerald J. Wasserburg was an American geologist. At the time of his death, he was the John D. MacArthur Professor of Geology and Geophysics, Emeritus, at the California Institute of Technology. He was best known for his work in the fields of isotope geochemistry, cosmochemistry, meteoritics, and astrophysics.

After leaving the U.S. Army, where he received the Combat Infantryman Badge, he attended college on the G.I. Bill. Wasserburg completed his Ph.D. from the University of Chicago in 1954, with a thesis on the development of krypton-argon dating. He joined the faculty at the California Institute of Technology (Caltech) in 1955 as Assistant Professor. He became Associate Professor in 1959 and Professor of Geology and Geophysics in 1962, and in 1982, became the John D. MacArthur Professor of Geology and Geophysics, retiring in 2001. Along with Typhoon Lee and Dimitri Papanastassiou, he discovered the presence of short-lived radioactive aluminum-26 in the early solar system and short-lived palladium-107.

Wasserburg was deeply involved in the Apollo program with the returned lunar samples, and was the last living member of the so-called “Four Horsemen,” whose other members were Bob Walker, Jim Arnold, and Paul Gast. He pioneered the precise measurement of ultra-small samples under strict clean room conditions with minimal contamination. He was also the co-inventor of the Lunatic Spectrometer (the first fully digital, mass spectrometer with computer controlled magnetic field scanning and rapid switching) and founder of the “Lunatic Asylum” research laboratory at Caltech, which specialized in high-precision, high-sensitivity isotopic analyses of meteorites and lunar samples. He and his co-workers were major contributors to establishing a chronology for the Moon and proposed the hypothesis of the late heavy bombardment (LHB) of the whole inner solar system.

Wasserburg’s research led to a better understanding of the origins and history of the solar system and its component bodies and the precursor stellar sources contributing to the solar system. This research established a timescale for the development of the early solar system, including the processes of nucleosynthesis and the formation and evolution of the planets, the Moon, and the meteorites.

Wasserburg was a member of the U.S. National Academy of Science, the American Philosophical Society, the American Academy of Arts and Sciences, and the Norwegian Academy of Science and Letters. He was also the recipient of numerous awards, including the Arthur L. Day Medal in 1970, the NASA Distinguished Public Service Medal in 1972 and 1978, the Wollaston Medal in 1985, the Gold Medal of the Royal Astronomical Society in 1991, the Bowie Medal in 2008, the H. Hess Medal of the American Geophysical Union in 1985, the Leonard Medal of the Meteoritical Society in 1975, the J. Lawrence Smith Medal of the National Academy of Science in 1985, the Holmes Medal of the European Union of Geosciences in 1986, and the V. M. Goldschmidt Medal of the Geochemical Society in 1978.