Robert S. Kraemer, NASA’s former director of planetary exploration who was also an expert in rocket engines, died Aug. 20 at an assisted living center in Catonsville, Md. He was 84.

The cause was complications from a fall at his home two months ago, said his son David Kraemer.

Mr. Kraemer joined NASA in 1967 and, in one of his early assignments, managed the development of a Mars surface laboratory mission at NASA’s headquarters in Washington.

After the project was canceled because of congressional concerns, he was appointed manager of advanced planetary programs and technology and in 1970 was named director of planetary programs.

“In this position he oversaw the successful completion of 12 missions to launch spacecraft into the solar system to study its planets, moons and more,” Brian Compere, assistant managing editor of the Diamondback newspaper at the University of Maryland, wrote in a profile of his grandfather. “He faced political, financial and technical challenges in managing an unprecedented burst of planetary exploration” that produced groundbreaking results.

Robert S. Kraemer, who served as NASA’s director of planetary exploration, died Aug. 20 at 84. (Family Photo)

Mr. Kraemer was associated with the missions Mariner 9 and 10, Pioneer 10 and 11, Helios 1 and 2, Viking 1 and 2, Voyager 1 and 2 and Pioneer Venus 1 and 2.

Noel Hinners, who had been associate administrator for space science at NASA’s headquarters, worked with Mr. Kraemer.

“Overall and first of all, Bob was very technically competent and a very good engineer, and he was very good at picking the right people for the right job,” said Hinners, who retired from NASA in 1979.

“He had an excellent staff to work all the details. He had a real good team who knew what the goal was and worked toward it. He could solve most of the problems that came up in the division, and sometimes he came to me. Viking was a major challenge at the time,” he said.

“Bob was a relatively quiet and an unassuming man. He paid a lot of attention to the details and went to visit contractors. He just didn’t read reports,” Hinners said. “He was the kind of person who got the most out of people.”

The son of a citrus rancher and a homemaker, Robert Samuel Kraemer was born on Oct. 21, 1928, in Fullerton, Calif., and raised in Placentia, Calif. He received a bachelor’s degree in aeronautical engineering from the University of Notre Dame in 1950.

After receiving a master’s degree in aeronautics and rocket propulsion from the California Institute of Technology in 1951, he worked for North American Aviation’s Rocketdyne Division in Canoga Park, Calif., on rocket propulsion for a secret intercontinental cruise missile called Navaho.

“By 1961, he was head of all advanced projects for the NAA rocket team, also called Rocketdyne. His work with high-performance launch engines during this time led him to determine they had all the rocket technology the U.S. would use for the next two decades,” Compere wrote.

Mr. Kraemer then worked as chief engineer for space systems at Ford Aeronutronic in Newport Beach, Calif., where he worked until he joined NASA. He retired in 1990.

Mr. Kraemer wrote several books, including “Rocketdyne: Powering Humans into Space” and “Beyond the Moon: A Golden Age of Planetary Exploration 1971-1981.” He received the Distinguished Service Medal, NASA’s highest honor.

He lived in Rockville from 1967 to 1981, when he moved to Annapolis. Since 2007, he had lived in Catonsville.

Survivors include his wife of 59 years, Anne Park Kraemer of Catonsville; six children, David Kraemer and Anita Kraemer, both of Catonsville, Timothy Kraemer of Germantown, Md., Stephen Kraemer of Athens, Ga., Kathryn McCoy of Kensington and Joan Compere of Ellicott City; two brothers; a sister; and 11 grandchildren.

— Baltimore Sun