Richard M. Goldstein, a pioneer in planetary exploration who used ground-based radar to map planets with techniques that scientists now use to measure geographic changes on Earth, including melting glaciers, died June 22 at his home in La Cañada Flintridge , California. He was 97.
His daughter, Rabbi Lisa L. Goldstein, confirmed the death.
In the early 1960s, Dr. Goldstein was an electrical engineering student at Caltech and working part-time at NASA’s Jet Propulsion Laboratory when he proposed as his dissertation topic a project in which he would try to detect echoes from Venus using the Goldstone solar system radar, which was recently developed by the space agency.
If they succeed, scientists will learn the distance from Earth to Venus, essentially laying the groundwork for mapping the entire solar system. His adviser at Caltech was more than skeptical; Venus, according to NASA’s description, was a “cloud-shrouded” planet covered in dense gases, and previous attempts to reach the planet using other radars had mixed results.
“No echo, no thesis,” Dr. Goldstein’s adviser told him, according to “Seeing the Invisible: A History of Planetary Radar Astronomy” (1996) by Andrew J. Butrika, historian of science.
He continued anyway. On March 10, 1961, technicians aimed the new radar at Venus. Six and a half minutes later, the signals from the planet returned. Dr. Goldstein had proved his advisor wrong. He soon rejected signals from Mercury and Mars, as well as Saturn’s rings.
The impact of the study on solar system research was enormous.
“The measurements he made of the distance to Venus made it possible to perform precise navigation within the solar system,” said Charles Werner, a former senior engineer at the Jet Propulsion Laboratory. “If you know one distance, it’s like a ruler that allows you to calibrate everything else and be able to accurately navigate spacecraft in the solar system.”
The radar echo was the celestial prelude to a long career at the Jet Propulsion Laboratory mapping the unseen. In the late 1960s and early 1970s, Dr. Goldstein used radar interferometry – the splicing of multiple radar signals over a period of time – to map the surface of Venus.
“High-resolution radar probes have pierced the thick clouds of Venus and for the first time discerned features on the planet’s surface, which is a landscape of vast, shallow craters,” science reporter John Noble Wilford wrote in a front-page New York Times article on 5 August 1973
“Instead of the blurry hues of earlier radar maps of the planet,” Mr. Wilford wrote, the images discovered by Dr. Goldstein reveal a dozen craters, including one that is 100 miles wide and less than a quarter of a mile deep.
Dr. Goldstein used two radar antennas 14 miles apart to create the images.
“This actually gives us stereo reception,” Dr. Goldstein said, allowing him to “point to any area touched by Venus.”
“We were able to see the depths better,” he added.
He later adapted his radar algorithms for use with aircraft and satellites that map melting glaciers, the movement of tectonic plates and other changes to the Earth’s surface.
“In terms of civilian remote sensing of the earth, he was the absolute pioneer,” said Paul A. Rosen, project scientist at the Jet Propulsion Laboratory.
Richard Morris Goldstein was born on April 11, 1927 in Indianapolis. His father, Samuel, owned Goldstein Brothers Department Store. His mother, Dorothy (Drozdowitz) Goldstein, oversaw the household.
After graduating from Purdue in 1947 with a degree in electrical engineering, Dr. Goldstein joined the family business and worked in the lamp department.
“I hold the record for selling the most three-way bulbs in Indianapolis,” he joked in an oral history interview with the National Radio Astronomy Observatory.
Eleven years later, Dr. Goldstein moved to California for graduate school and took a low-level job at the Jet Propulsion Laboratory, where he worked for 43 years, retiring as a senior scientist. He completed his PhD at Caltech in 1963.
“He broke every problem down to its basics,” Mr. Rosen said. “He went about his business quietly. He didn’t like to tell the world how great he was.”
Dr. Goldstein married Ruth Lowenstam in 1964. She survives him, along with their daughter Lisa; their sons Samuel and Joshua; three grandchildren; and a great-grandson. His brother, Samuel Goldstein Jr., an astronomer, died earlier.
During his tenure at the Jet Propulsion Laboratory, and even after his retirement, Dr. Goldstein was an enthusiastic competitor in the organization’s annual Invention Challenge, in which participants attempt to solve strange problems, such as creating “a device that can to place up to 10 Ping – Pong Balls in a Mason Jar located five meters away within the one minute time.”
“I’d say he probably won at least a third of the time,” his daughter said. “He loved those races. He was obsessed with finding the solution.”
