Robert H. Goddard | |
Robert Hutchings Goddard (1882-1945) |
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Personal information | |
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Name | Robert H. Goddard |
Nationality | American |
Birth date | October 5, 1882 |
Birth place | Worcester, Massachusetts |
Date of death | August 10, 1945 (aged 62) |
Place of death | Baltimore, Maryland |
Work | |
Significant advance | controlled, liquid-fueled rocketry |
Robert Hutchings Goddard, Ph.D. (October 5, 1882 – August 10, 1945), U.S. professor and scientist, was a pioneer of controlled, liquid-fueled rocketry. He launched the world's first liquid-fueled rocket on March 16, 1926. From 1930 to 1935, he launched rockets that attained speeds of up to 885 km/h (550 mph). Though his work in the field was revolutionary, he was sometimes ridiculed for his theories. He received little support during his lifetime, but would eventually be recognized as one of the fathers of modern rocketry.[1][2]
Goddard was born in Worcester, Massachusetts to Nahum Danford Goddard (1859–1928) and Fannie Louise Hoyt (1864–1920). Robert was their only child to live to adulthood. Another, younger, son was born with physical disabilities, and died not long after birth. With the introduction of electric power in American cities in the 1880s, the young Goddard became interested in science. When his father showed him how to generate static electricity on the family's carpet, the five-year-old's imagination was inspired. Robert experimented, believing he could jump higher if the zinc in batteries could somehow be charged with static electricity. The experiments failed, but his interest continued unabated.
Goddard developed a fascination with flight, first with kites and then with balloons. He also became a thorough diarist and documenter of his own work, a skill that would greatly benefit his later career. These interests merged at age 16, when Goddard attempted to construct a balloon made from aluminum, shaping the raw metal in his home workshop. After nearly five weeks of methodical, documented efforts, he finally abandoned the project, remarking, "Failior [sic] crowns enterprise." However, the lesson of this failure did not restrain Goddard's growing determination and confidence in his work.
He became interested in space when he read H.G. Wells's science fiction classic The War of the Worlds when he was 16 years old. His dedication to pursuing rocketry became fixed on October 19, 1899. While climbing a cherry tree to cut off dead limbs, he imagined, as he later wrote, "how wonderful it would be to make some device which had even the possibility of ascending to Mars, and how it would look on a small scale, if sent up from the meadow at my feet."[3] For the rest of his life he observed October 19 as "Anniversary Day", a private commemoration of the day of his greatest inspiration.
A thin and frail boy, almost always in fragile health, with stomach problems, colds and bronchitis, Goddard fell two years behind his classmates. He became a voracious reader, regularly visiting the local public library to borrow books on the physical sciences. Later, he continued his formal schooling as an 18-year-old sophomore at South High School in Worcester. His peers twice elected him class president. At his graduation ceremony in 1904, he gave his class oration as valedictorian. In his speech, Goddard included a phrase that would become emblematic of his life: "It has often proved true that the dream of yesterday is the hope of today, and the reality of tomorrow." Goddard enrolled at Worcester Polytechnic Institute in 1904. He quickly impressed the head of the physics department, A. Wilmer Duff, with his thirst for knowledge. Professor Duff took him on as a laboratory assistant and tutor.
At Worcester, he joined the Sigma Alpha Epsilon fraternity, and began a long courtship with Miriam Olmstead, an honor student who was second in his high school class. Eventually, she and Goddard were engaged, but they drifted apart and ended the engagement around 1909.
While still an undergraduate, Goddard wrote a paper proposing a method for "balancing aeroplanes", and submitted the idea to Scientific American, which published the paper in 1907. Goddard later wrote in his diaries that he believed his paper was the first proposal of a way to stabilize aircraft in flight. His proposal came around the same time as other scientists were making breakthroughs in developing functional gyroscopes.
Goddard received his B.S. in physics from Worcester Polytechnic Institute in 1908, and after serving a year as an instructor in Physics at Worcester Tech, he enrolled at Clark University in Worcester in the fall of 1909.
His first writing on the possibility of a liquid-fueled rocket came in February 1909. Goddard had begun to study ways of increasing a rocket’s efficiency using methods differing from conventional, powder rockets. He wrote in his journal about using liquid hydrogen as a fuel with liquid oxygen as the oxidizer. He believed a 50 percent efficiency could be achieved with liquid fuel.
Goddard received his M.A. from Clark University in 1910 and then completed his Ph.D. at Clark in 1911. In 1912, he accepted a research fellowship at Princeton University.
In the decades around 1900, radio was a new technology, a fertile field for innovation. In 1911, while working at Clark University, Goddard investigated the effects of radio waves on insulators.[4] In order to generate radio-frequency power, he invented a vacuum tube that operated like a cathode-ray tube. U.S. Patent 1,159,209 was issued on November 2, 1915. This was the first use of a vacuum tube to amplify a signal, preceding even Lee de Forest's claim.[5][6][7] It thus marked the beginning of the electronic age.
In early 1913, Goddard became seriously ill with tuberculosis and was forced to leave his position at Princeton. He returned to Worcester, where he began a prolonged recovery.
It was during this recuperation that Goddard began to produce his most important work. In 1914, his first two landmark patents were accepted and registered. The first, U.S. Patent 1,102,653 , described a multi-stage rocket. The second, U.S. Patent 1,103,503 , described a rocket fueled with gasoline and liquid nitrous oxide. The two patents would become important milestones in the history of rocketry.
From 1916-1917, Goddard built and experimented with ion thrusters, which he imagined could be used for propulsion at near-vacuum conditions at very high altitudes. The small glass engines he built were tested at atmospheric pressure, where they generated a stream of ionized air. [8]
In the fall of 1914, Goddard's health had improved enough for him to accept a part-time teaching position at Clark University. By 1916, the cost of his rocket research was becoming too much for his modest teaching salary to bear. He began to solicit financial assistance from outside sponsors, beginning with the Smithsonian Institution, which agreed to a five-year grant totaling $5,000. Worcester Polytechnic Institute allowed him to use its Magnetics Laboratory on the edge of campus during this time.
Not all of Goddard's early work was geared towards space travel. He developed the basic idea of the bazooka and, using a music rack for a launcher, demonstrated the weapon at Aberdeen Proving Ground two days before the Armistice that ended World War I. Another Clark University researcher continued Goddard's work on the bazooka, leading to the weapon used in World War II.
In 1919, the Smithsonian Institution published Goddard's groundbreaking work, A Method of Reaching Extreme Altitudes. The book describes Goddard's mathematical theories of rocket flight, his experiments with solid-fuel rockets, and the possibilities he saw of exploring the earth and beyond. Along with Konstantin Tsiolkovsky's earlier work, The Exploration of Cosmic Space by Means of Reaction Devices (1903), Goddard's book is regarded as one of the pioneering works of the science of rocketry, and is believed to have influenced the work of subsequent pioneers such as Hermann Oberth, Wernher von Braun and Sergey Korolev.
Goddard described extensive experiments with solid-fuel rocket engines burning high grade nitrocellulose "smokeless" powder. A critical breakthrough was the use of the steam turbine nozzle invented by the Swedish inventor Gustaf de Laval. The de Laval nozzle allows the most efficient ("isentropic") conversion of the energy of hot gases into forward motion.[9] By means of this nozzle, Goddard increased the efficiency of his rocket engines from 2 percent to 64 percent and obtained supersonic exhaust speeds of over Mach 7.[10][11]
Though most of this work dealt with the theoretical and experimental relations between propellant, rocket mass, thrust and velocity, a final section (pp. 54-57) titled Calculation of minimum mass required to raise one pound to an "infinite" altitude discussed the possible uses of rockets, not only to reach the upper atmosphere, but to escape from Earth's gravitation altogether. Included as a thought experiment was the idea of launching a rocket to the moon and igniting a mass of flash powder on its surface, so as to be visible through a telescope. He discussed the matter seriously, down to an estimate of the amount of powder required; Goddard's conclusion was that a rocket with starting mass of 3.21 tons could produce a flash "just visible" from Earth. Forty years later, Goddard's concept was vindicated when the Soviet space probe Luna 2 impacted the Moon on September 14, 1959, though radio tracking did away with the need for flash powder.
Goddard eschewed publicity, and his imaginative ideas about space travel were only shared with private groups. In a letter to the Smithsonian dated March 1920, he discussed: photographing the Moon and planets from rocket powered flyby probes, sending messages to distance civilizations on inscribed metal plates, the use of solar energy in space, and the idea of high-velocity ion propulsion. In that same letter, Goddard clearly describes the concept of the ablative heat shield, suggesting the landing apparatus be covered with "layers of a very infusible hard substance with layers of a poor heat conductor between" designed to erode in the same way as the surface of a meteor.[12]
The publication of Goddard's document gained him national attention from U.S. newspapers, most of it negative. Although Goddard's discussion of targeting the moon was only a small part of the work as a whole and was intended as an illustration of the possibilities rather than a declaration of Goddard's intent, the papers sensationalized his ideas to the point of misrepresentation.
On January 12, 1920 a front-page story in The New York Times, "Believes Rocket Can Reach Moon," reported a Smithsonian press release about a "multiple charge high efficiency rocket." The chief application seen was "the possibility of sending recording apparatus to moderate and extreme altitudes within the earth's atmosphere," the advantage over balloon-carried instruments being ease of recovery since "the new rocket apparatus would go straight up and come straight down." But it also mentioned a proposal "to [send] to the dark part of the new moon a sufficiently large amount of the most brilliant flash powder which, in being ignited on impact, would be plainly visible in a powerful telescope. This would be the only way of proving that the rocket had really left the attraction of the earth as the apparatus would never come back."[13]
The next day, an unsigned New York Times editorial delighted in heaping scorn on the proposal. The writer attacked the instrumentation application by questioning whether "the instruments would return to the point of departure... for parachutes drift just as balloons do. And the rocket, or what was left of it after the last explosion, would need to be aimed with amazing skill, and in a dead calm, to fall on the spot whence it started. But that is a slight inconvenience...though it might be serious enough from the [standpoint] of the always innocent bystander...a few thousand yards from the firing line."[14] The full weight of scorn, however, was reserved for the lunar proposal: "after the rocket quits our air and really starts on its longer journey it will neither be accelerated nor maintained by the explosion of the charges it then might have left. To claim that it would be is to deny a fundamental law of dynamics, and only Dr. Einstein and his chosen dozen, so few and fit, are licensed to do that." It expressed disbelief that Professor Goddard actually "does not know of the relation of action to reaction, and the need to have something better than a vacuum against which to react" and even talked of "such things as intentional mistakes or oversights." Goddard, the Times declared, apparently suggesting bad faith, "only seems to lack the knowledge ladled out daily in high schools."[14] (Forty-nine years later, on July 17, 1969, the day after the launch of Apollo 11, The New York Times published a short item under the headline "A Correction", summarizing its 1920 editorial mocking Goddard, and concluding: "Further investigation and experimentation have confirmed the findings of Isaac Newton in the 17th century and it is now definitely established that a rocket can function in a vacuum as well as in an atmosphere. The Times regrets the error.")
After one of Goddard's experiments in 1929, a local Worcester newspaper carried the mocking headline "Moon rocket misses target by 238,799 1/2 miles."
As a result of harsh criticism from the media and from other scientists, and understanding better than most the military applications that foreign powers could use this technology for, Goddard became increasingly suspicious of others and often worked alone, which limited the impact of his work.
Goddard began experimenting with liquid oxygen and liquid-fueled rockets in September 1921, and bench tested the first liquid-fueled engine in November 1923. It had a cylindrical combustion chamber, using impinging jets to mix and atomize liquid oxygen and gasoline. An engine using regenerative cooling was constructed that year, which circulated liquid oxygen around the combustion chamber, but the design was rejected as too complex.
He launched the first liquid-fueled rocket on March 16, 1926 in Auburn, Massachusetts. His journal entry of the event was notable for its laconic understatement: "The first flight with a rocket using liquid propellants was made yesterday at Aunt Effie's farm." The rocket, which was dubbed "Nell", rose just 41 feet during a 2.5-second flight that ended in a cabbage field, but it was an important demonstration that liquid-fuel propellants were possible. The launch site is now a National Historic Landmark, the Goddard Rocket Launching Site.
Viewers familiar with more modern rocket designs may find it difficult to distinguish the rocket from its launching apparatus in the well-known picture of "Nell". The complete rocket is significantly taller than Goddard, but does not include the pyramidal support structure which he is grasping. The rocket's combustion chamber is the small cylinder at the top; the nozzle is visible beneath it. The fuel tank, which is also part of the rocket, is the larger cylinder opposite Goddard's torso. The fuel tank is directly beneath the nozzle, and is protected from the motor's exhaust by an asbestos cone. Asbestos-wrapped aluminum tubes connect the motor to the tanks, providing both support and fuel transport.[15] This layout is no longer used, since the Pendulum Rocket Fallacy showed that this was no more stable than placing the rocket engine at the base. After a series of modifications, by May, the engine was placed in the classic position, at the lower end of the rocket to simplify the plumbing.
After a launch of one of Goddard's rockets in July 1929 again gained the attention of the newspapers, Charles Lindbergh learned of his work. At the time, Lindbergh had begun to wonder what would become of aviation in the distant future, and had settled on rocket flight as a probable next step. He contacted Goddard in November 1929. The professor met the aviator soon after in Goddard's office at Clark University. Upon meeting Goddard, Lindbergh was immediately impressed by his research, and Goddard was similarly impressed by the flier's interest. He discussed his work openly with Lindbergh, forming an alliance that would last for the rest of his life.
By late 1929, Goddard had been attracting additional notoriety with each rocket launch. He was finding it increasingly difficult to conduct his research without unwanted distractions. Lindbergh discussed finding additional financing for Goddard's work, and put his famous name to work for Goddard. Into 1930, Lindbergh made several proposals to industry and private investors for funding, which proved all but impossible to find following the recent U.S. stock market crash in October 1929.
Lindbergh finally found an ally in the Guggenheim family. Financier Daniel Guggenheim agreed to fund Goddard's research over the next four years for a total of $100,000. The Guggenheim family, especially Harry Guggenheim, would continue to support Goddard's work in the years to come.
With new financial backing, Goddard eventually relocated to Roswell, New Mexico in 1930, where he worked in near isolation and secrecy for a dozen years. By September 1931, his rockets had a classic aerodynamic appearance of a smooth casing and tail fins. He began experimenting with gyroscopic guidance and made an unsuccessful flight test of such a system in April 1932. A gyroscope on gimbals electrically controlled steering vanes in the exhaust, similar to the system used by the German V-2 over 10 years later.
A temporary loss of funding from the Guggenheims forced Goddard to return to Clark University until 1934, when funding resumed. Upon his return to Roswell, he began work on his A series of rockets 4 to 4.5 meters long, powered by gasoline and liquid oxygen pressurized with nitrogen. The gyroscopic control system was housed in the middle of the rocket, between the propellant tanks. In March 28, 1935, the A-5 successfully flew to an altitude of 1.46 km using his guidance system. This rocket also achieved supersonic velocity.
In 1936-1939, Goddard began work on the K and L series rockets, which were much more massive and designed to reach very high altitude. This work was plagued by trouble with engine burn-through. Ironically, Goddard had built a regeneratively cooled engine in 1922, but deemed the idea too complicated. Subsequently, he used fuel curtain cooling, spraying excess gasoline on the inside of the combustion chamber, but this was not working well, and the large rockets failed. Returning to a smaller design again, the L-13 reached an altitude of 2.7 km, the highest of any of Goddard's rockets. Weight was reduced by using thin-walled fuel tanks wound with high tensile strength wire.
From 1940-1941, work was done on the P series of rockets, which used propellant turbopumps (also powered by gasoline and liquid oxygen). Higher fuel pressure permitted a more powerful engine, but two launches both ended in crashes after only reaching an altitude of several hundred meters.
Though he brought his work in rocketry to the attention of the United States Army, he was rebuffed, since the Army largely failed to grasp the military application of rockets.
In Nazi Germany, however, Wernher von Braun took Goddard's plans from various journals and incorporated them into building the early 1930s A-1 and A2 prototypes of the Aggregate series that later, designated A4 or V-2, constantly struck at Europe in the last two years of World War II.[16] In 1963, von Braun, reflecting on the history of rocketry, said of Goddard: "His rockets...may have been rather crude by present-day standards, but they blazed the trail and incorporated many features used in our most modern rockets and space vehicles".[17]
German Intelligence kept an eye on Goddard's work. An accredited military attache to the US, Friedrich von Boetticher, sent a four-page report in 1936, and the spy Gustav Guellich sent a mixture of facts and made-up information, claiming to have visited Roswell and witnessed a launch.[18][19]
Goddard was nonetheless extremely secretive. In August 1936, he was visited by Frank Malina, who was then studying rocketry at the California Institute of Technology. Goddard declined to discuss any of his research, other than that which had already been published in Liquid-Propellant Rocket Development. This deeply troubled Theodore von Kármán, who was at that time Malina's mentor. Later, von Kármán wrote, "Naturally we at Cal Tech wanted as much information as we could get from Goddard for our mutual benefit. But Goddard believed in secrecy.... The trouble with secrecy is that one can easily go in the wrong direction and never know it." By 1939, von Kármán's Guggenheim Aeronautical Laboratory at Cal Tech had received Army Air Corps funding to develop rockets to assist in aircraft take-off. Goddard learned of this in 1940, and openly expressed his displeasure.[20]
After his offer to develop rockets for the Army was declined, Goddard temporarily gave up his preferred field to work on experimental aircraft for the U.S. Navy. Goddard confirmed his work was used by von Braun in 1944. Shortly before the Nazis began firing V-2s at England, a V2 crashed in Sweden. It was sent to the Annapolis lab where Goddard was doing research for the Navy. Goddard recognized many components which he had invented and sadly realized his brain child had been turned into a mass killer.[21] However, Goddard would not design any more rockets of his own.
Unfortunately, he learned he had throat cancer in 1945, and died that year in Baltimore, Maryland. He was buried in Hope Cemetery in his home town of Worcester, Massachusetts.[22]
Goddard was awarded 214 patents for his work, 83 of which came during his lifetime.
The Goddard Space Flight Center was established in 1959. The Goddard crater on the Moon is also named in his honor.
The Dr. Robert H. Goddard Collection and the Robert Goddard Exhibition Room are housed in the Archives and Special Collections area of Clark University's Robert H. Goddard Library. Outside the library lies a structure depicting the flight path of Goddard's first liquid fuel rocket.
The Chemical Engineering department at Worcester Polytechnic Institute is housed in Goddard Hall.
His home town of Worcester established the Goddard School of Science and Technology, an elementary school, in 1992. Robert H. Goddard High School was completed in 1965 in Roswell, New Mexico and dedicated by Esther Goddard. The school's mascot is appropriately titled "Rockets". Robert H. Goddard Middle School is located in Glendora, California. The school's mascot is the Titan IIIC missile. Another Goddard Middle School is located in Littleton, Colorado. There is also a Robert Goddard Middle School in Prince Georges County, Maryland.
The Civil Air Patrol Cadet Program Goddard Achievement, corresponding to promotion to Cadet Chief Master Sergeant is named for him.
Now Pakachoag golf course in Auburn, MA, at the site where Goddard launched the very first liquid-propelled rocket, holds a small memorial with a statue in his name.