Artur Kantrowitz, a prominent American scientist of late twentieth century, died in age of 95 in New York City on November 29, 2008. Founder of Avco Everett Research Labs, professor of Dartmouth College, champion of Science Court and versatile inventor, he will be always remembered. In this short note I just like to say a word about one of his greatest ideas and contributions to society, which will benefit future generations of our planet. I am talking about his role in founding of laser propulsion.
Laser Propulsion is a part of advanced rocket science, but the concept is so simple, that you dont have to be a rocket scientist to grasp it. Do you know that on average we pay ten grand per every pound of a payload delivered to low earth orbit. Sounds a bit pricey. Unfortunately, we have no choice, because the only way to deliver that pound is to use a rocket, hydrogen (mainly) burning tube (most sophisticated in modern technology), filled with fuel, oxidizer, cryogenics, tanks, lines, etc. with a little room for a cargo. It is inefficient to carry all fuel onboard, and so is the price. If only we could separate the source of burning energy from the vehicle, deliver this energy from outside, the savings on weight and efficiency will be dramatic.
The energy can be beamed to the rocket with powerful lasers! The original idea on beaming energy to a space rocket was invented by Konstantin Tsiolkovsky in 1924. Genius and visionary, Tsiolkovsky could not know about lasers (the first laser was demonstrated in 1960), so he was talking about tight beams of light, beamed to a rocket and hence providing it with necessary energy or, in other words, making the rocket much more energy efficient. In 1924 all this was just a dream, a few decades later Arthur Kantrowitz presented the world with scientifically sound plan for turning this dream into reality.
In 1972 Arthur Kantrowitz published in Astronautics and Aeronautics Propulsion to Orbit by Ground Based Lasers, a scientific paper which started a new field: laser propulsion. In this paper Kantrowitz proposed to change our very approach to space launches: instead of building larger (and even less energy-efficient rockets), start using high-power lasers for space launches of small satellites. Such satellites would literally straddle the tip of laser beam, focused on their propellant area. When high power laser beam is focused (even loosely) on a solid matter, such matter is evaporated and ionized almost instantaneously, i.e. the release of energy is much higher than one used from burning hydrogen in rockets. So, laser-driven vehicle will be still flying on the same rocket principle, but exhaust energy and structural lightness will be incomparably superior to hydrogen-burning rockets.
Laser-propelled rocket will be made of light focusing optics (mirrors), modest amount of ablative solid fuel, and the rest is a payload. No more need for heavy fuel/oxidizer, tanks, lines, chambers, nozzles! Kantrowitz called it 4P Principle: Payload, Propellant and Photons, Period! Scientifically proven (and repeated in different ways for many times) calculations show that with the laser propulsion space delivery price will be reduced to $100 per pound of a payload! It is hundredfold savings!
The paper of Dr. Kantrowitz from 1972 marked the beginning of a new scientific quest. In early seventies Kantrowitz has initiated first research program on laser propulsion at Avco-Everett Research Labs, which for over a decade was the only research program in this field in the world. Later other projects ensued, first laser-propelled vehicles were launched (not into space yet, but high enough to prove the viability of an idea), other countries (Russia, Japan, Germany, China) and hundreds of scientists and engineers joined the quest for laser propulsion (and other forms of beamed-energy propulsion, such as microwave propulsion). However, we should always remember one man who started it all: Arthur Kantrowitz, the father of laser propulsion. - 16928
Laser Propulsion is a part of advanced rocket science, but the concept is so simple, that you dont have to be a rocket scientist to grasp it. Do you know that on average we pay ten grand per every pound of a payload delivered to low earth orbit. Sounds a bit pricey. Unfortunately, we have no choice, because the only way to deliver that pound is to use a rocket, hydrogen (mainly) burning tube (most sophisticated in modern technology), filled with fuel, oxidizer, cryogenics, tanks, lines, etc. with a little room for a cargo. It is inefficient to carry all fuel onboard, and so is the price. If only we could separate the source of burning energy from the vehicle, deliver this energy from outside, the savings on weight and efficiency will be dramatic.
The energy can be beamed to the rocket with powerful lasers! The original idea on beaming energy to a space rocket was invented by Konstantin Tsiolkovsky in 1924. Genius and visionary, Tsiolkovsky could not know about lasers (the first laser was demonstrated in 1960), so he was talking about tight beams of light, beamed to a rocket and hence providing it with necessary energy or, in other words, making the rocket much more energy efficient. In 1924 all this was just a dream, a few decades later Arthur Kantrowitz presented the world with scientifically sound plan for turning this dream into reality.
In 1972 Arthur Kantrowitz published in Astronautics and Aeronautics Propulsion to Orbit by Ground Based Lasers, a scientific paper which started a new field: laser propulsion. In this paper Kantrowitz proposed to change our very approach to space launches: instead of building larger (and even less energy-efficient rockets), start using high-power lasers for space launches of small satellites. Such satellites would literally straddle the tip of laser beam, focused on their propellant area. When high power laser beam is focused (even loosely) on a solid matter, such matter is evaporated and ionized almost instantaneously, i.e. the release of energy is much higher than one used from burning hydrogen in rockets. So, laser-driven vehicle will be still flying on the same rocket principle, but exhaust energy and structural lightness will be incomparably superior to hydrogen-burning rockets.
Laser-propelled rocket will be made of light focusing optics (mirrors), modest amount of ablative solid fuel, and the rest is a payload. No more need for heavy fuel/oxidizer, tanks, lines, chambers, nozzles! Kantrowitz called it 4P Principle: Payload, Propellant and Photons, Period! Scientifically proven (and repeated in different ways for many times) calculations show that with the laser propulsion space delivery price will be reduced to $100 per pound of a payload! It is hundredfold savings!
The paper of Dr. Kantrowitz from 1972 marked the beginning of a new scientific quest. In early seventies Kantrowitz has initiated first research program on laser propulsion at Avco-Everett Research Labs, which for over a decade was the only research program in this field in the world. Later other projects ensued, first laser-propelled vehicles were launched (not into space yet, but high enough to prove the viability of an idea), other countries (Russia, Japan, Germany, China) and hundreds of scientists and engineers joined the quest for laser propulsion (and other forms of beamed-energy propulsion, such as microwave propulsion). However, we should always remember one man who started it all: Arthur Kantrowitz, the father of laser propulsion. - 16928
About the Author:
Dr. Andrew Pakhomov is founder and president of American Institute of Beamed Energy Propulsion, a nonprofit society serving to development and popularization of this advanced space technology AIBEP He is also associate professor of physics at University of Alabama in Huntsville. To read more about Arthur Kantrowitz and fascinating field of beamed-energy propulsion, please visit official site of AIBEP.
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