In Memoriam

The Mars Exploration Rovers team lost 10 of their own during the 15-year lifetime of mission, and one who for so many years regaled them with his stories. Each of these Martian explorers is remembered fondly and has been deeply missed since they left this plane of existence. The Mars Explorations Rovers Update remembers them here.

Jens Martin Knudsen, PhD
Oct.12, 1930 – Feb. 17, 2005
Professor Emeritus, Niels Bohr Institute, University of Copenhagen

Astrophysicist, MER Athena Science Team member, and one of the senior leaders on the mission, Jens Martin was the intellectual leader behind the Danish magnet experiments on Spirit and Opportunity, which provided a simple yet elegant way to understand the magnetic phases of minerals. 

His path to MER began during a talk he gave at a European Space Agency (ESA) meeting in the early 1990s. Although he spoke on using Mössbauer spectroscopy to measure the magnetic and crystallographic properties of solids, like meteorites, he also proposed a simple magnet experiment for a landed Mars mission that would build on the Viking experiments. Although MER was not yet even a concept, Steve Squyres, who happened to be in the audience that day, was listening.

One thing led to another and in 1993 Jens Martin became an adviser to NASA’s Mars Exploration Program. Before MER, he provided the Danish experiment on Pathfinder that examined the magnetic properties of Martian dust. 

As a professor and public speaker, his ability to communicate physics and astronomy enthralled audiences and made him a science legend in Denmark. Jens Martin’s ardent enthusiasm about the Red Planet and his work with Pathfinder and MER earned him the nickname "Marsmanden” (The Martian) in his homeland. He is now regarded as the pioneer of putting magnets onto rovers.

Jens Martin authored or co-authored more than 100 scientific articles in his lifetime and was honored many times over with awards, including the prestigious Order of the Dannebrog, an order of chivalry that dates to 1671 and Christian V. He died of cancer at the age of 74.

The MER team named Knudsen Ridge, along Marathon Valley at Endeavour Crater, in his honor.

Larry A. Haskin, PhD   
Aug. 17, 1934 – Mar. 24, 2005
Ralph E. Morrow Distinguished Professor Washington University St. Louis (WUSTL)
Chair, Department of Earth & Planetary Sciences 1976-1990

Internationally renowned as a planetary geochemist and mineralogist, Larry was a MER Athena Science Team member who brought a high level of integrity and vast experience to the mission.

As a senior member, he was a guiding force for the team, especially during the mission’s early days in Gusev Crater. Throughout his time on MER, team members looked to him for scientific leadership and found solace in his way of keeping things going on an even keel.

A founding father of lunar science, Larry was one of the first to study the Apollo Moon rocks. NASA honored him for his work in 1971, and two years later, he became Chief of the Planetary and Earth Sciences Division at NASA’s Johnson Space Center. Posthumously, the International Astronomical Union (IAU) named a crater on the Moon in his memory.

Although he remained active with NASA throughout his career, Larry missed academia and moved to WUSTL in 1976 to teach and chair the new Department of Earth and Planetary Sciences. During the ensuing 15 years, he turned the program into one of the finest in the country. When he stepped down, MER’s Ray Arvidson was chosen to fill the position. 

Universally recognized as a wonderful teacher, researcher, and mentor, Larry could be forceful and held high expectations of those with whom he worked. The MER team admired him for this and for his deep insight and leadership during the most intense times. He died after a long struggle with myelofibrosis, a blood disorder. He was 70.

Haskin Ridge,a prominent formation on the east side of the Husband Hill summit, was named in his honor.

Robert A. Mitcheltree, PhD
Apr. 28, 1961 – Jan. 6, 2006
Aerospace Engineer / Aerothermodynamicist, Jet Propulsion Laboratory 

Regarded as the leading expert on aerodynamics and experimental scaling at JPL, Bob was the verification and validation lead for the entry, descent, and landing phases of Spirit and Opportunity. 

After earning his PhD in aerospace engineering at North Carolina State University, Bob became a civil servant at NASA Langley in 1989. There, his work as an aerothermodynamicist demonstrated an engineering prowess others envied.

In 2001, he moved to JPL to work on MER. Colleagues viewed his critical mind, careful and penetrating insight, and unwavering intellectual integrity as gifts to the entry, descent and landing (EDL) team and the mission.

During the early days of development, Bob, a consummate creator, constructed a sting system for a balsa wood mock-up of the MER lander, secured it on his Jeep Wrangler, and then hit the 210 freeway, where he managed to acquire first-order aerodynamic measurements. He planned and executed many tests for MER and through a rigorous, disciplined verification and validation program, he ultimately ensured the success of the Spirit and Opportunity landings.

Bob understood that technical excellence is how the United States achieved all it has in aviation and spaceflight and that shaped the way he spent every day of his professional life. He cherished his MER experience, friends say, and loved the thrill of seeing something he designed operate successfully on Mars. He was even more proud to have contributed to the expansion of humanity's scientific knowledge.

Bob died unexpectedly when his truck swerved off the road and hit a tree. He was only 44.

Mitcheltree Ridge, just east of Home Plate in Gusev Crater, was named in his honor. 

John  Richard "Rich" Morris  
Nov. 25, 1973 – Oct.17, 2011
Systems Engineer / MER Mission Manager, Jet Propulsion Laboratory

Rich was an Oklahoma boy who wanted to join the space program and he did. 

He left his home in Edmond and headed west to California, where he earned a degree in Natural Science at Pepperdine University. He then went on to the University of Southern California, graduating in 1998 with an advanced degree in aerospace engineering.

After interning for a few defense companies, Rich was hired into the robotic space program at JPL in 2001 and joined the MER team. He worked as a tactical activity planner/sequence integration engineer, tactical uplink lead, and mission manager. 

With MER on a brutal deadline to make the launch window in 2003, the work environment was often highly stressful, but Rich was quiet, calm, friendly, and always smiling, his mission mates say, a welcoming presence amidst the pressure. In 2008, he was assigned to the Mars Science Laboratory (Curiosity), where he worked as a sequencing software cognizant engineer.

Rich was also a talented actor, musician, and photographer. He sang lead and played guitar in a 1970s cover band named Marcia, Marcia, Marcia and garnered fans in the local pubs of Pasadena. He also enjoyed acting in plays presented by Theater Arts at Caltech, playing soccer and watching Sooner football. For reasons no one knows, he took his own life. He was only 37.

The MER team named Morris Hill along Endeavour Crater’s inner rim in his honor. 

Ronald Greeley, PhD 
Aug. 25, 1939 – Oct. 27, 2011
Regents’ Professor of Planetary Geology, Arizona State University
Director, NASA-ASU Regional Planetary Image Facility

A founding father of planetary geology, Ron was passionate about exploring Mars and was a MER Athena Science Team member who brought deep experience and scientific oversight to the mission.

Involved in lunar and planetary studies since 1967, Ron began working with NASA at the Ames Research Center helping the agency prepare for the Apollo missions to the Moon, and years later became the investigator of the Planetary Aeolian Laboratory there. 

Before MER, Ron worked on numerous Red Planet missions, including Mariners 6, 7, and 9; Viking; Mars Pathfinder, Mars Global Surveyor, and the European Space Agency’s Mars Express. He also contributed significantly to our understanding of other planetary bodies within our solar system through such missions as Magellan to Venus, Galileo to Jupiter, and Voyager 2 to Uranus and Neptune.

Renowned for his leadership and breadth of knowledge of planetary surface and atmospheric processes, Ron played a key role in creating the School of Earth and Space Exploration at ASU after joining the faculty in 1977.

A pioneer in planetary science experiments, Ron created a vertical gun to study impact cratering processes and used wind tunnels to study the behavior of wind-blown sand particles and dunes, important features on the surfaces of Earth, Mars, Venus, and Saturn's largest moon Titan.

During his career, he wrote or co-wrote more than 400 papers and 16 books, served on various NASA and National Academy of Sciences panels, and received many awards, including the Geological Society of America’s G.K. Gilbert Award. He was named a Fellow of the American Geophysical Union and the American Association for the Advancement of Science (AAAS).

Ron died unexpectedly at home. He was 72.  At the time of his passing, he was chairman of the NASA Advisory Council’s planetary science subcommittee.

In his honor, the MER team christened the site where Opportunity her spent fifth Martian winter Greeley Haven. Subsequently, the IAU named an impact crater on Mars in his memory. 

Jacob R. “Jake” Matijevic, PhD 
Nov. 3, 1947 - Aug. 20, 2012
Control Systems Engineer, Telerobotics Engineer, First Chief of MER Engineering
Jet Propulsion Laboratory 

If there was any one person who represented the heart and soul of Spirit and Opportunity, it was Jake, MER team members say. One of the original group that developed the concept for the mission, he was the go-to engineer everyone looked to because of his profound knowledge about the rovers.

Jake grew up on Chicago’s Southeast Side. After graduating from Mt. Carmel High School, he enrolled at the Illinois Institute of Technology where he earned his Bachelor’s degree in mathematics in 1969. He went on to the University of Chicago and earned his Master’s in 1970, and immediately began his doctoral studies in mathematics under adviser Dr. Irving Kaplansky. In 1973, he completed his PhD. From his early contributions to this field, he developed the Matijevic Theorem, which has been called “one of the most beautiful results of recent years in commutative algebra.”

After teaching math at the University of Kentucky and the University of Southern California, he moved to JPL in 1981 to work as a control systems engineer. By 1986, he was working in telerobotics, where he developed integrating mechanical arms, machine vision systems, and sensing instruments into a working telerobot system.

Around 1992, he became Project Manager for Sojourner, the tiny rover that Mars Pathfinder would deliver to the surface of the Red Planet in 1997. He then moved seamlessly onto MER. Quiet and unassuming, everyone loved Jake.

As he saw it, his greatest professional success as an engineer came from working on the rovers. “A substantial portion of my work life has been devoted to Spirit and Opportunity,” he said years ago. “I have been very privileged to do this.” 

Jake's work helped enable humanity explore the surface of another world. He published more than 40 papers and garnered many top NASA and JPL awards. In 2015, Illinois Institute of Technology honored him with its Lifetime Achievement Award.

After a lifelong battle with asthma and other upper respiratory ailments, Jake died during a traumatic lung event at his home in L.A. He was 64.

Matijevic Hill on Cape York at Endeavour Crater, where the MER team uncovered the first ancient clay minerals on the surface of Mars, was named in his honor.

Thomas J. Wdowiak, PhD  
Dec. 1, 1939 – Apr. 27, 2013
Associate professor emeritus of physics, University of Alabama Birmingham

An Athena Science Team member, Tom was one of the senior scientists on MER whose broad scientific oversight and contributions were critical to many of the mission’s successes.

Beyond his knowledge of physics, he was an expert in chemistry and mineralogy, and had a comprehensive knowledge of the kinds of minerals the rovers might find on the surface of Mars. 

Tom was part of the team working with the iron-detecting Mössbauer spectrometers onboard Spirit and Opportunity, which allowed the scientists to examine rocks and soil up close on the planet's surface. He knew the instrument inside and out and was instrumental in interpreting and analyzing data that helped the team uncover evidence that water was once present on Mars

Born in Binghamton, New York, he attended colleges in New York and Florida, and earned his PhD in Astronomy and Astrophysics at Case Western Reserve University. After four years at NASA Marshall Space Flight Center in Huntsville, Alabama, he moved to the University of Alabama Birmingham, where he spent most of his career, teaching more than 10,000 students in general astronomy courses. 

Tom published some 90 scientific papers, and had a gift for sharing his boundless passion for the wonders of science with the public. Locally, he was famous for "Tommy Test Tubes," a full-color page of kid's science experiments that ran every Saturday in the Birmingham News / Post Herald. 

Remembered for his warmth, booming laughter, and infectious, unbridled enthusiasm for science and exploration, team members found him a joy to work with. Exploring Mars had been a lifelong dream, so when Spirit reached out to study her first rock, Adirondack, Tom fulfilled his childhood dream of touching another world.

Tom battled diabetes for many years. He was 73 when he passed away.

The MER team named a 500-foot long ridge that rises prominently 40 feet above its surroundings on the western rim of Endeavour Crater, about 200 yards west of the rim’s main crest line, in his honor. 

Heinrich Wänke, PhD   
Sep. 5, 1928– Nov. 21, 2015
Nuclear physicist, Cosmochemist
Former Director Max Planck Institute for Chemistry 

One of the greats of planetary geochemistry, Heinrich was extremely important to the MER mission for his invaluable oversight on the Alpha Particle X-Ray Spectrometer (APXS), and contributions to the science team’s publications.

Prior to MER, he was responsible for the Alpha Proton X-Ray Spectrometer that was developed in his department at the Max Planck Institute, and used to conduct the first chemical rock analyses on the Red Planet during the Mars Pathfinder mission. 

Born in Linz, Austria, Heinrich studied physics in Vienna, and then earned his PhD in nuclear physics. While studying in England in 1953, he “discovered’ meteorites. Researching them and collecting them would become a lifelong passion. That same year, he began working at the Mainz Institute as an assistant to Professor Friedrich Paneth, then the director of the Radiochemistry department. 

Fourteen years later, Wänke was hired to head the Cosmochemistry Department at the Max Planck Institute for Chemistry in Mainz, which focused on studying the chemical compositions of matter in the early universe and processes that led to those compositions. He was there until he retired and is considered one of the fathers of cosmochemistry.

Wänke’s research gained international recognition and he was honored with many accolades and awards. Until his retirement in 1996, he maintained an extensive collection of 1,900 meteorites. When the Cosmochemistry Department closed in 2005, his collection was permanently loaned to the Senckenberg Research Institute in Frankfurt. He considered working with the APXS on Pathfinder and his study of a lunar rock from the Apollo 11 mission among the highlights of his scientific career.

MER team members who knew Heinrich doubt there would have been an APXS on the twin rovers without his APXS work on Sojourner. Since he was retired and not directly involved MER mission ops, Ralf Gellert, then a research scientist at the Max-Planck Institute for Chemistry, stepped up as lead scientist for the APXS instruments on Spirit and Opportunity.

Heinrich died at the age of 87.

Göstar Klingelhöfer, PhD  
Oct. 2, 1956 – Jan. 8, 2019
Johannes Gutenberg-Universität, Mainz, Germany

The intellectual father and creator of the miniaturized Mössbauer spectrometers for MER, Göstar was the Payload Element Lead for these instruments on Spirit and Opportunity.

Known the world over and highly honored for his contributions to this spectroscopic technique based on the Mössbauer effect discovered by Rudolf Mössbauer in 1958, he was probably most renowned Mössbauer spectroscopist in the world, according to the International Board of the Applications of the Mössbauer Effect (IBAME). 

A powerful tool for quantitative mineralogical analysis of iron‐bearing materials, the Mössbauer had been used in Earth‐based laboratories to study the mineralogical composition of iron‐bearing phases in a variety of planetary samples, including lunar samples returned to Earth by the Apollo astronauts, Soviet robotic missions, and meteorites that have asteroidal or Martian origins. But no in situi measurements with a Mössbauer spectrometer had ever been made on any planetary mission beyond Earth.

So, Göstar developed the miniature Mössbauer spectrometer (MIMOS II) for Spirit and Opportunity to use for close-up investigations into the mineralogy of iron-bearing rocks and soils on the Martian surface. He built the instruments, tested them, put them onto the rovers, and operated them. As creator of MIMOS II, he is credited with expanding the use of the use of Mössbauer spectrometry beyond laboratory measurements on Earth.

By 2012, the Mössbauer’s Cobalt-57 power source was too weak for Opportunity to effectively study any more rocks or soils. 

With his use of Mössbauer spectrometry in planetary science and the resounding success he achieved with the miniaturized versions on MER, Göstar opened the door for other MB spectroscopists to continue expanding the technology in creative ways. 

After returning from a trip to China with plans for various new projects, Göstar died suddenly and unexpectedly. He was 62.

Posthumously, he was honored with the IBAME Award. The MER team has plans to name a site on Mars in his honor for all the work he did with Spirit and Opportunity and the MER mission.

Brenda Franklin, MS 
Apr. 10, 1943 – Mar. 29, 2019
Planetary geologist, Jet Propulsion Laboratory

A planetary geologist at JPL for more than 30 years, Brenda was the Hazcam and Navcam Payload Uplink Lead for the MER ops team, but was always helping out wherever and whenever she was needed.

She arrived late to her career at JPL because, interestingly enough, she worked as Bette Midler’s personal assistant for years before deciding to trade show business for science.

In addition to taking images with the engineering cameras, Brenda served as a mother figure for the MER ops team. As colleagues put it, she took care of everybody and the rovers too. A fierce-minded, fearless Texan, she didn’t coddle, but rather always told people the truth and usually in a very blunt manner. 

“Brenda kept us human,” as one team member put it. “If we started getting mad at one another or lost our temper, we’d look over at her. It was like looking at your mom.”

She was as tough as she was dedicated. One day as she was getting ready to go to work, she fell and broke her hip. Barely able to move and in agonizing pain, Brenda managed to get to her shift with a little help from paramedics, refusing to go to the hospital until someone could get there to replace her.

Brenda always told her younger colleagues that she was not going anywhere until Opportunity was gone. She retired about a year before the June 2018 dust storm that took Oppy, but true to her word, she would wait until NASA officially declared the end of mission.

About six weeks later, early in the morning on March 29^th, Brenda passed away peacefully in her sleep. She was 75. 

Ray Bradbury
Aug. 22, 1920 – Jun. 5, 2012
Author – Emmy Award Winning Screenwriter – First Martian

The author who took so many people to Mars with The Martian Chronicles wasn’t a member of the MER team, but he could have been. The team would have welcomed “the first Martian” with open arms.  

Actually, Ray was a MERtian for an afternoon. Following a press event and gathering at JPL on Jan. 15, 2009 to celebrate the mission’s first 5 Earth years, rover drivers Ashley Stroupe and Scott Maxwell maneuvered through the crowd to invite the Special Guest of Honor to the MER ops room. 

While Bradbury finished an interview, Ashley and Scott went to prepare for their Martian visitor, along with a few other team members. 

He arrived soon enough and after checking out a full-scale MER model, his assistant wheeled Bradbury to the console, where a 3-D model of a site on Mars with a simulated rover on the screen greeted him. Although Ray never learned to drive on Earth, driving on Mars was something he wanted to try. 

As a small group of MERtians, includng John Callas and Steve Squyres, watched, Scott showed the beloved author how to move the rover around. After a few fits and starts, Ray, his eyes dancing, began driving the rover all around the screen, loving every move.

Bradbury’s career spanned 70 years. He won scores of awards, including the National Medal of Arts in 2004, and a Pulitzer citation “for his distinguished, prolific and deeply influential career as an unmatched author of science fiction and fantasy” in 2007. He died peacefully at his home in Los Angeles, following a lengthy illness. 

The New York Times headlined his obituary “Ray Bradbury, Who Brought Mars to Earth With a Lyrical Mastery, Dies at 91.” He was posthumously acknowledged at the 85^th Academy Awards, and the corner of 5^th and Flower in downtown L.A. was named in his honor.

Cherished by the MER team, countless mission followers, and millions of readers around the world, Ray was and forever will be Martian royalty.

“The Martians were there. Timothy began to shiver.

The Martians were there – in the canal – reflected in the water...The Martians stared back up at them for a long, long silent time from the rippling water...”

– excerpt, The Martian Chronicles