9-1 Man Versus Machine
Introduction a. The U.S. Army, in conjunction with NASA's Astronaut Program, has been an active participant in the U.S. manned spaceflight program since the beginning of the Shuttle program. (See Chapter 2, Army Space History.) This program has focused on conducting research experiments and gathering scientific data. Army personnel may apply for entry into the NASA astronaut program. Every year the Army has a selection board which considers all qualified applicants, selects a list of candidates and forwards the list to NASA, which in turn makes the final selection of astronaut candidates. The Army has both men and women astronauts, therefore the Military Man In Space program refers to "humans", not just males.
Ultimate High Ground b. Throughout history, it has been advantageous to be on the high ground above the battlefield. Space has been referred to as the "ultimate high ground." The objective of the Military Man In Space Program and other research programs is to determine which activities in space can be applied to meet terrestrial military requirements and how the Army can take advantage of these capabilities to enhance its operational effectiveness.
Significant Contribution c. Although the capabilities of unmanned spacecraft are critical, experience has shown that manned spacecraft have also made significant contributions to the United States' space knowledge and capabilities. In many ways, humans are more versatile than machines. Unmanned satellites are machines which can accomplish tasks for which they are designed. They are, however, not well suited for accomplishing additional new tasks. They can gather data or perform a multitude of other tasks, but only when humans have determined that the capability is necessary. If satellite designers are not aware of a particular phenomena or capability, they do not design a satellite to gather data on the phenomena or to accomplish that task.
Humans Adapt d. Humans can function well in spite of uncertainty, ambiguity, change, unexpected occurrences and incomplete information. They can think, interpret, reason, and adapt. Machines do not perform well under these conditions.
Human Advantages e. Humans are particularly adept at perceiving patterns, even when not expected. A human is able to selectively observe and vary his focus on ground targets or objects not previously captured on film. Satellite sensors are limited to specific wavebands and lack the ability to capture movement and to provide true color representation. The human eye, on the other hand, is capable of capturing movement and discriminating between thousands of colors and hues. The human eye requires only 4% contrast, while commonly used sensors are in the range of 30%. The analytical capability of humans also enables them to differentiate between small, closely spaced objects. For example, a U.S. Navy oceanographer who was on board one of the shuttle missions noticed that, under certain conditions, relatively straight lines were visible on the ocean surface below. It was discovered that these were wakes of ships. In some cases the wakes were visible several days after the ship had passed through the area. No sensors had been designed to detect this phenomena because no one had thought that wakes would be observable from space for such a long time in the turbulent oceans. On other missions, astronauts have detected geological features that had not been detected by sensors because scientists and engineers had not known about them and, therefore, had not designed sensors to do so.
Modifying Experiments f. The astronauts often modify experiments to get them to function properly or to acquire additional data not originally included in the experiment plan. In May 1992, on the maiden flight of the shuttle Endeavor, the crew attempted to recover an Intelsat communications satellite that was stranded in low Earth orbit. The capture procedures had been worked out in detail and rehearsed for many months prior to the launch. The first two attempts were unsuccessful. After consultation with NASA and Intelsat engineers on the ground, three astronauts went into the shuttle bay and constructed mounts from parts intended for other experiments. Then they grabbed the satellite with their hands and maneuvered it to a new booster motor stored in the shuttle bay. It is doubtful that a machine would have proven to be so innovative and resourceful.
9-1 Man Versus Machine, cont'd
Military Personnel g. Additionally, man can interact with the commander on the ground in real time, reporting observations and responding to developing situations. It takes an experienced military person to be able to combine special skills with military knowledge.
Machines h. Of course, unmanned spacecraft can do things that people cannot do or do not want to do. Machines can travel through areas of intense radiation, they can perform missions that are considered to be high risk, and sensors can see areas of the electromagnetic spectrum that humans cannot even detect. Machines can perform repetitive tasks without getting bored. Computers can calculate more quickly. As with any other job, machines are tools that can make humans more productive.
9-2 Military Missions for Man in Space
Introduction a. In 1986 the Department of Defense established an official Military Man in Space (MMIS) Program. The Air Force is the DoD Executive Agent and the Space Division, Deputy Chief of Staff for Operations and Plans, Department of the Army is the Army's executive agent. The program was implemented as part of the DoD Space Test Program to evaluate man's ability to enhance military operations from space. DoD holds an annual board to review and prioritize proposed Military Man in Space experiments. Three experiments are discussed below:
Terra View b. Terra View is a four phased experiment to make observations of ground sites. The first three phases will be conducted on shuttle flights with phase IV leading towards the future space station. The first phase of Terra View determined what Army astronauts, using cameras and binoculars, could observe from space that is of military value. The astronauts observed both CONUS and OCONUS training areas. In the second phase of Terra View, the Army augmented the astronauts with communications equipment to allow them to pass information directly to ground commanders in real time. Army Colonel Jim Adamson participated in this portion of Terra View. Phase three will use Army experts, instead of astronauts, to observe ground activity and communicate tactical information to the ground commander. This phase encompasses two approved Army MMIS experiments, Terra Scout and Terra Geode. Lessons learned from the site observations and direct communications between the Shuttle and ground sites were used to determine the Army's requirements.
Terra Scout c. The Army Intelligence Center and School developed and is sponsoring Terra Scout. The intent of Terra Scout is to determine what an experienced imagery interpreter can observe of military value from onboard the Space Shuttle. The Shuttle crewmembers used the Spaceborne Direct View Optical System (SPADVOS). The SPADVOS is a developmental device which uses a manual pointing and tracking system with manually controlled zoom lens. This optical system allows the operator to view terrestrial targets with image degradation caused by current systems. On orbit observations will be reported using a UHF SATCOM radio compatible with the Army's PSC-3, UHF radio. The Army selected two Warrant Officers and one Non-Commissioned Officer as primary, backup and alternate payload specialist candidates. Army Astronaut LTC Jim Voss and Payload Specialist CW3 Tom Hennen performed the first phase of Terra Scout during Space Shuttle Mission STS-44 in November 1991.
Terra Geodo d. The Army Chief of Engineers proposed the use of a military geologist to evaluate terrain conditions for tactical movement in January 1987. Terra Geode is a four phase experiment. Phases I and II results, based on NASA astronauts observations, have helped to refine the experiment design and strengthen justification for an expert observer to fully explore potential applications for military man in space. Phase I was conducted by military astronauts using standard equipment available to NASA under the Earth Observation Program. Phase II observations were conducted by Dr. Kathy Sullivan, a NASA astronaut with a geologic background, during a five day space shuttle mission launched 24 April 1990. She demonstrated the feasibility of terrain analysis from earth orbit and was able to make basic observations of the ground targets, determine soil color, type, ground cover, and other terrain data. She also provided guidance for improving the conduct of the next phase of the experiment. Dr. Sullivan completed Phase II of Terra Geode during another shuttle flight into space in 1992. Phase III will be carried out by an Army geologist on the Shuttle. This will be the demonstration and validation phase that will prove the value of employing the capabilities of a trained expert military observer. Phase IV will propose a space station experiment to evaluate the potential utility for the permanent stationing of military geologist/terrain analysts on the space station. The Army has selected three officers and one warrant officer as primary, backup and alternate Payload Specialists.
9-3 Human Support for Extended Space Flight
Introduction a. As space technology progresses and more experience is gained, it is likely that men and women will spend longer periods in space. The environment in space is much different than that on Earth. All life support needs must be carried onboard the spacecraft or periodic resupply missions need to be launched to replenish consumables.
Radiation Hazards b. The intensity of radiation in space is significant. Exposure to radiation has a variety of short term and long term effects on the human body based on the type radiation, the intensity and the length of exposure. It is not presently known what all of those effects are. Radiation generating events on the Sun are unpredictable and occur frequently. Radiation emanating from deep space is also dangerous but it is more constant. Exposure to high energy galactic cosmic rays is not a serious problem in low Earth orbit. Beyond low Earth orbit, however, shielding against radiation can be bulky and massive, thus making the spacecraft heavier to launch. Additional research on the effects of radiation and protective materials for the crewmembers is needed.
Microgravity c. The microgravity environment in space is responsible for a number of physical effects and changes on the human body. Some of the effects have immediate impact and others have a long term effect.
Motion Sickness d. Motion sickness is the most noticeable and immediate reaction to weightlessness in a microgravity environment. It affects about 40% of all astronauts and can last up to four days. Eventually, the body adapts and the motion sickness goes away. Some experienced astronauts still experience motion sickness but the duration is usually shorter. Motion sickness has significant impact on crewmembers' ability to perform certain tasks effectively and efficiently. A number of medications are being used to reduce the length and severity of motion sickness.
Body Fluid Changes e. In a weightless environment, body fluids are distributed around the body more evenly. The result is that the upper body contains more fluid than normal. It is not unusual for astronauts to get puffy eyelids, slightly swollen faces and a feeling of nasal congestion. The body interprets this redistribution as an increase in the amount of blood in the body. It corrects for this by initiating fluid loss, adjusting the number of red blood cells. After about five weeks a new equilibrium is established.
Heart Deconditioning f. The heart does not have to work as hard in space as it does on Earth. Over a prolonged period the heart will become weaker. While in space this is not a serious problem. Upon reentry to the Earth's gravity an unprepared heart could be severely stressed. Part of the solution is for astronauts to maintain a rigorous exercise schedule and a proper diet.
Muscular Deconditioning g. Muscles are needed on Earth to counter the force of gravity. In space, muscles can atrophy (weaken) from lack of use. Crew members can use exercise machines on board the spacecraft to help counteract some of the muscle breakdown. Data collected indicates, however, that up to 20% of leg muscle strength and 10% of arm muscle strength are lost, even with exercise. These effects appear to be reversible following short term spaceflight. The ability to recover following a long space flight is not known.
Bone Mineral Loss h. The mineral content of bones in the body changes in space. Calcium loss occurs progressively throughout a flight. It is possible that bone mineral loss may be a limiting factor to long term space travel.
Psychological Considerations of Extended Space Flight i. In addition to significant physical problems which must be addressed, there are also significant issues associated with the psychological state of mind of crew members. Crews will be made up of people with different educational levels, skills, vocations, gender and nationality. It can be expected that the interior of the spacecraft will be crowded, as the shuttle is today. This results in a lack of privacy which leads to increased tension and crew stress. Work must be productive and not repetitive so that crewmembers do not become bored. Recreation and relaxation time is also needed. The fact is that more research is needed into the identification of problems associated with long term spaceflight and the development of solutions.