"This facility, a product of internation cooperation on a large scale, is available today for the science and application community. NASA and ESA are currently integrating the first Spacelab payload and flight system leading to its initial flight in October 1983. This event will mark the start of a new era in space utilization and investigation. The remaining challenge will be the imaginative and beneficial use of this unique facility."
 Life Sciences
Not from Mars. Not from Jupiter. Certainly not from any flying saucer. What makes these space travelers look unlike Earthlings is the strange headgear they are wearing. Fold back the face plate and behind the forbidding exterior appear the familiar faces of the SL-1 payload specialists. They take turns donning a unique helmet containing "visual stimulation and recording devices."
The SL-1 payload specialists, on board Spacelab to conduct scientific experiments, also serve as prime research subjects themselves in several of the 15 on-board life sciences experiments. With the help of the mission specialists they conduct research on themselves and on each other.
Throughout the flight, from launch through landing, each payload specialist wears a standard battery-powered medical recorder on his belt. Wires from the recorder run to small electrodes glued to the head and chest. The electrodes monitor heartbeat, eve movements, and the electrical activity of the brain.
Upon return to Earth, scientists correlate each section of the recordings with the wearer's activities in space at the time the recording was made. Researchers are particularly interested in the recordings during launch and reentry and during sleep in weightlessness.
Similar measurements have been made of crews on earlier space flights. What is different this time?
"In the past, personnel exposed to prolonged weightlessness were a select group of astronauts," earthbound scientists emphasize. "Now the people who will go into space in Spacelab are more representative of the general population in age, physical fitness, and previous stress exposure. Nothing is known vet about the physiological reaction of this 'normal' population to the stress of space flight. We want to collect physiological data on normal people in an abnormal environment- in this case, the payload specialists in weightlessness."
The information they gather may become the basis for later studies, particularly when payload specialists of almost any age and from very different backgrounds are allowed to fly in orbit on future Spacelab missions. The information could become a guide for crew selection and for planning in-orbit activities. The scientists who sponsor this....
 .....experiment and who will analyze the recordings are from the Clinical Research Center in the United Kingdom and they call their instrument the Personal Miniature Electrophysiological Tape Recorder.
Backpack Experiment Unique
Payload crew members will occasionally take turns wearing a backpack containing devices which measure the tiny body vibrations caused by natural processes.
"Just as a pistol recoils when it fires, the human body reacts to each heartbeat with little movements," Italian scientists from a research team at the University of Rome who will analyze this experiment's results have stated. They will compare the readings made while the crew members are floating freely in weightlessness in orbit with recordings made of the same crew members on the ground before and after the SL-1 mission. The backpack contains an electrocardiograph (EKG) and three small accelerometers for measuring movements in three dimensions. These are usually very difficult to chart under the influence of gravity on Earth. The experiment is called Three-Dimensional Ballistocardiography in Weightlessness.
Four experiments- two from the United States and one each from Switzerland and West Germany- require taking blood samples from crew members before, during, and after the flight. Comparison of the samples is expected to show whether any reduction of disease-fighting antibodies occurred during weightlessness. Experimenters will be watching for reductions in antibody-producing lymphocytes and of hormones in the blood, as well as a lessening of the quantity of blood in crew members. These experiments also require in-flight measurements of blood pressure in arm veins to determine shifts of fluids to the upper body. All of these changes have been observed in crews on earlier space flights. Why and how these changes take place in weightlessness is only vaguely understood.
Weight-Guessing Game Planned
In another experiment the payload specialists and mission specialists play a 20-minute game. From a box containing 24 small steel balls they remove 2 balls at a time and judge which ball in each pair would be the heavier on Earth. All of the balls are of the same size, but on Earth each has a different weight. The difference is not easy to discern in weightlessness. Recorded answers....
 ....by the crew are expected to help scientists determine how well each member adapts to making certain judgments in weightlessness and to what extent weight differences can be appraised in orbit. The test, called Mass Discrimination During Weightlessness, was designed by researchers at the University of Stirling, United Kingdom. Performance in weightlessness will be compared with results from the same test upon return to Earth to detect how rapidly crew members readapt to normal gravity.
The visual stimulation and recording helmet mentioned at the beginning of this chapter is one of three pieces of research equipment used by the crew for several experiments that are among the most important on board SL-1. All three items are meant to help scientists learn more about the human body's gravity-sensitive organs in the inner ear. Disturbances of these organs- the otolith and vestibular organs- are believed to be responsible for the space motion sickness which has plagued about half of the people who have gone into space.
Will Study Motion Sickness.
Pinpointing the cause and finding methods for preventing or lessening space motion sickness are major objectives of SL-1's science program.
Known by NASA medical people as space adaptation syndrome"- and on Earth variously as sea, air, or car sickness- the illness causes rapid breathing, profuse salivation, cold sweat, and feelings of apprehension, general discomfort, and nausea.
The unique helmet is engineered to project various images to the wearer's eyes, giving him his only visual clues about his body's position. The experiment is conducted while the wearer floats in weightlessness inside the Spacelab module. Restraint devices prevent him from touching walls, floor, ceiling, or other objects that might help him orient himself. His only indications of his position come from helmet-generated images and from orientation organs in his inner ear. If clues from these two sources disagree, disorientation and motion sickness may result.
Designed by researchers at the Johannes Gutenberg University in West Germany, the helmet is used for an experiment conducted by a team at the German university as well as a team at the Massachusetts Institute of Technology and in Canada. Dr. Byron K. Lichtenberg, an sit-1 payload specialist, is a member of the MIT team which prepared this experiment for analyzing the brain's adaptation to the unusual conditions in weightlessness. A related equipment item,....
 ....from researchers at NASA'S Johnson Space Center, detects changes in spinal reflexes and posture when weightlessness disturbs the body's usual means of orientation.
SL-1 crew members will not be the only living organisms aboard Spacelab. In other life sciences experiments, dwarf sunflower seedlings are videotaped at different stages of their growth. Scientists want to observe the directions in which plants will grow when there is no gravity to indicate the direction of "up." In another experiment, a fungus grows in total darkness so scientists can determine whether absence of gravity as well as normal day-night cycles cause changes in fungi's 24 hour growth cycle. The fungi's customary growth changes are governed by a 24-hour cycle called "circadian rhythms ''believed to he triggered by day-night clues or other subtle environmental changes. Or it may be due to internal mechanisms unaffected by any exterior happenings. This experiment was prepared by the State University of New York at Binghampton.
Life sciences experiments, second in number only to materials science experiments on SL-1, will continue to receive high priority on future Spacelab flights. Two scientist-astronauts, Dr. Norman E. Thagard and Dr. William E. Thornton, both physicians, have been assigned as mission specialists to Spacelab's third flight, expressly for continuing research on the space adaptation syndrome. NASA wants to learn whether it Will he possible to identify persons who are particularly vulnerable to it, whether its onset can he predicted, and what countermeasures can be taken against it. The SL-3 flight- (STS-18)- will include experiments in materials processing, space technology, and life sciences.
Dr. Thagard conducted extensive research on the problem while assigned as a mission specialist on STS-7 in June 1983, as did Dr. Thornton as a mission specialist on STS-8 in August 1983.
Still more extensive research on space motion sickness and a variety of other medical and biological subjects is planned on the fifth Spacelab flight ((SL-4)) which is the first discipline mission entirely dedicated to life sciences research. Twenty-four experiments on that flight will cover a wide range of medical and biological subjects aimed at safeguarding human health in space, using the orbital environment to advance knowledge in medicine and biology and using space technology for solutions of medical and biological problems on Earth.
Life science experiments will also be a large part of the D-1 German mission payload.
Astronomy and Solar Physics
Six instruments aboard SL-1 are designed for studies of the Sun and stars. These instruments examine radiations which cannot penetrate the Earth's atmosphere and, therefore, cannot be studied from the ground.
Three of the instruments- one each from the United States, France, and the Netherlands- examine radiations from the stars. Three other instruments- one each from the United States, France, and Belgium- study radiations from the Sun.
One of the instruments- the French star camera- is mounted in the airlock in the experiment module. The other five instruments are mounted on the pallet.
Newer and better instruments to delve deeper into the mysteries of the universe continue to emerge, and Spacelab is sampling some of them on its first flight. All of them exploit the obvious advantage of observation from orbit: the absence of the Earth's obstructing atmosphere. Researchers expect that in the relatively few days available for experiments during Spacelab's flight, more and better observations can be made than would be possible in several decades from the Earth.
 Not only do observations from orbit guarantee cloudless, haze-free viewing, but instruments there have access to that majority of radiations from stars and other celestial objects which cannot penetrate the Earth's atmosphere and therefore are unobservable from the ground. Only a small segment of radiations in the electromagnetic spectrum reaches low altitudes or the Earth's surface. Most radiations are filtered or absorbed by the upper atmosphere.
Even for detection of those radiations which can reach the ground- including visible light- the atmosphere poses a persistent handicap to scientific sky watchers. Ever-present water vapor and dust distort or block incoming radiations. Debris from volcanic eruptions often remains in the upper atmosphere for several years. Added to these natural hindrances are such synthetic impediments as smoke, smog, and electronic interference. Light from cities often overwhelms faint star light. Many astronomers consider themselves fortunate if in the course of a year they obtain several hours of good viewing.
 Space technology has opened a huge new window to astronomy. Not surprisingly, astronomical instruments were among the first scientific sensors to be attached to the earliest space rockets. Instruments on early sounding rockets made important astronomical discoveries. They detected stars emitting X-rays which are not detectable from the ground. These achievements are especially remarkable since these instruments remained above the atmosphere for only a few minutes before falling back to Earth. Since then many satellites have been outfitted with astronomical instruments, and astronauts on manned space flights have made valuable observations.
Beyond satisfying curiosity about the nature of our universe, astronomy research could produce many practical results. For example, the processes by which quasars and pulsars produce vast quantities of energy remain unexplained. Understanding them could lead to new energy-generating techniques that could provide inexhaustible and inexpensive energy supplies on Earth. Astronomical observations in the 16th and 17th centuries helped originate theories leading to some of the mechanisms that made possible the Industrial Revolution of the 18th and 19th centuries that still influence our lives today.
Astronomy Studies Planned
Having astronomers at work in space and operating an observatory there is one of the main purposes for building Spacelab. The third Spacelab flight - SL-2- has a large part of the mission devoted to astronomy. Its 13 major experiments are entirely devoted to astronomy and Sun research, including infrared astronomy, solar physics, and plasma physics.
Scientists call SL-2 a "super mission," because its experiments call for the largest and heaviest astronomy instruments ever taken into space. Transporting equipment of such size and weight into orbit was impracticable or impossible until Space Shuttle.
A special structure will be installed in the shuttle cargo bay to support a dome-topped two-ton cosmic ray detector. With its.....
 ....rounded top it appears like a giant boiled egg in a holder, at the extreme back of the cargo bay. In front of it on a pallet rests a telescope specializing in infrared observations. Ahead of it, on another pallet, is a telescope for observation of X-ray emissions from celestial sources. And ahead of it, on a third pallet, are four Sun telescopes guided by the new Instrument Pointing System (IPS), which will be making its first flight.
Igloo to Supply Pallets
Three pallets will be used simultaneously for the first time on this mission. It requires no habitable module because all of the experiments aboard can readily be controlled by payload and mission specialists from the Orbiter's flight deck or remotely from the ground. To house various items of equipment which would otherwise be inside a module because they require a normal atmosphere or moderate temperatures, an igloo will be installed ahead of the front pallet.
SL-2 was originally expected to be the second Spacelab flight, as its designation clearly indicates. Delays in the completion of the one-ton IPS, a very complex precision instrument designed as an aid for orbital astronomy observations, caused SL-2 to be postponed to March 1985, so that it will take place later than SL-3, now scheduled for September 1984. Despite this transposition, flight officials have decided to retain the SL-2 and SL-3 mission numbers as they were originally assigned.
SL-3, also a dedicated mission- meaning the Orbiter's facilities are exclusively devoted to Spacelab- is the first operational Spacelab flight in which the primary objective is the acquisition of scientific data rather than the testing and verification of Spacelab systems.
Many of SL-3's major experiments take advantage of the absence of normal gravity. To maintain weightlessness or very low gravity, the crew will refrain as much as possible from firing the craft's thrusters for steering or positioning the craft. Changes in spacecraft position or orbital paths cause at least slight disruption of the weightless state. Key research on the mission will include materials-processing and life-sciences experiments.
 Study of Stars Planned
On the first Spacelab flight- SL-1 - the United States and France each has a star and a Sun observation instrument. The Netherlands has a star observation experiment, and Belgium has a Sun observation experiment.
The three star experiments are designed to help scientists study the life cycle of stars from their births through their deaths.
Sky Survey- The French astronomy instrument aboard SL-1 is a Very Wide-Field Camera that the crew uses to take wide-angle ultraviolet-light photographs of vast regions of sky not observable from Earth. Very little large scale ultraviolet mapping of the sky has been accomplished to date. A payload specialist and a mission specialist install the instrument, a combination telescope camera, into the experiment module's scientific airlock during the flight. Photographs will be used by the Laboratory of Space Astronomy in France for large-scale studies of the structure of the Milky Way galaxy. Astronomers will examine remnants of gigantic explosions that occurred eons ago in the galaxy's center. Ultraviolet radiation is characteristically emitted by very young stars shortly after they form, and by very old stars near the ends of their life cycles.
Ultraviolet Telescope- A companion experiment is to be conducted by the United States with an instrument whose major components were built in France. It uses wide-field sensors, more sensitive than ever used before in space, for extensive surveys s of very taint sources of ultraviolet radiations. The instrument, called a Far Ultraviolet Space Telescope, has previously been used only for brief rocket observations.
The sensors are sufficiently sensitive to detect the very faint ultraviolet emissions believed to emanate from stars reaching the ends of their lives. The crew will operate this pallet-mounted experiment from controls inside the module. Analysis of the findings will he made by researchers in France and at the University of California, Berkeley, California.
X-ray Detector- An experiment by ESA S European Space Research and Technology Center in the Netherlands detects X rays emitted by stars. X rays originate during violent events in a star's life cycle. The pallet mounted instrument, controlled from on board and from the ground, contains Xenon gas that responds to bombardment by X rays. As the instrument measures these responses, scientists can determine the strength and....
Close-up of a Spacelab-1 pallet before its installation in the Orbiter's cargo bay shows the variety of instrumentation that can be accomodated by Spacelab on a single flight.
.....other characteristics of the X rays for clues to evolutionary processes inside the star.
Sun Energy Output to be Measured
Three Sun observation experiments seek to measure the Sun's energy output and its variations. The Sun's radiations are the major influence on our weather.
Sun Monitor- An automated pallet mounted instrument requiring no attention from the crew contains three heat detectors (pyroheliometers). They measure the Sun's radiations, ranging from those in the extreme ultraviolet through those in the tar infrared. The instrument, called an Active Cavity Radiometer, is being carried aboard Spacelab for scientists at the Jet Propulsion Laboratory in Pasadena, California, who will analyze the measurements.
Energy Detector- This pallet-mounted instrument, called a Solar Spectrum Monochromator, measures three separate kinds of radiations to determine the Sun's energy emissions. Three measuring and counting devices called double monochromators are used- one each for ultraviolet, visible, and infrared radiations- to detect variations in Sun radiations in each radiation range. Changes in each of these ranges have different effects on the atmosphere. Analysis of this experiment's data will be made by the Avionics Service of the National Center for Scientific Research in France. The observations with this instrument and with the radiometer (described above) are the first simultaneously measuring the Sun's total radiations in different spectral ranges from space.
Radiation Sensor- Controlled by the Spacelab computer and payload crew, this radiation sensor (pyroheliometer) attempts to measure the solar constant, the total radiation received on the Earth from the Sun, with great accuracy. This measurement also helps determine how much solar radiation is reflected back into space or absorbed by the Earth and helps determine Earth's energy gain, or "radiation budget." The Royal Meteorological Institute in Belgium will analyze the results of this experiment and compare this data with the measurements of the other two Sun observation experiments aboard SL-1- the radiometer and the monochromators described above. All of these three instruments are expected to be reflown repeatedly in space for measurements over long periods of variations in Sun output.
 Atmospheric Physics and Earth Observations
Six instruments aboard SL-1 are designed to study the Earth- four of them the Earth's atmosphere and two the Earth's surface.
The two surface observation instruments are from West Germany. Three of the atmospheric study instruments are from France and one is from the United States.
Four of these instruments are mounted on the pallet, one is inside the module, and one has components on the pallet and in the module.
Even before the earliest satellites confirmed it, scientists were convinced that a vantage point in orbit would make an ideal observation position for studies of Earth. Its lands, oceans, and atmosphere could be viewed from a new perspective and in ways never before possible.
Earlier experience with instruments on balloons, aircraft, and rockets showed they provide only limited information. Their point of view is Iocalized. Sounding rockets which reach altitudes above the atmosphere can look over large areas but their viewing time is very short. Automated Earth observation satellites do provide a sweeping view of vast regions, but the resolution of their observations is usually relatively low because they most often orbit at high altitudes.
Spacelab, at its relatively low orbital altitude, is expected to combine the sweeping view with high-resolution observations and give scientists the added advantage of crews aboard who can focus and adjust the equipment as they monitor it for best possible results.
Six Experiments Study Earth
Metric Camera- Only a little more than one-third of the Earth's land areas have been mapped adequately for the global resources planning required to accommodate the planet's rapidly increasing population. Conventional techniques are too slow to provide the needed up-to-date maps. SL-1 carries a metric camera similar to those used in surveys from airplanes. In-orbit tests will determine whether the camera can be used from space to map the remaining two-thirds of Earth's lands within a short time. The camera, which is being included for experimenters in West Germany, uses 24 centimeter ( 10-inch) film to provide photographs with much better resolution than is obtained from most unmanned, automated Earth-observation satellites. The crew mounts the camera in the core module's viewport. The camera is controlled by the Spacelab computer and the payload crew.
Microwave Sensor- Uninterrupted monitoring of Earth conditions for the benefit of agriculture and for the fishing and....
 ....transportation industries can be obtained through microwave sensing from orbit. To develop such a system for a planned European satellite that can "see" land and ocean surfaces through clouds and under all weather conditions, a microwave radar facility is being flown on SL-1 for scientific investigators in West Germany. The facility's antenna is mounted on the pallet, but the instrument's other components are in the module. The instrument is operated automatically. Data processed by the on board computer is transmitted to the ground for analysis.
Atmospheric Studies- A 16-mm movie camera on board SL-1 will take some 2,000 photographs to learn about the origin and behavior of cloudlike phenomena which have been observed in the atmosphere at altitudes of about 85 kilometers ( 53 miles). The camera is part of a French experiment called Waves in the OH Emissive Layer for studies of the atmosphere from orbit. Another French instrument called the Grille Spectrometer is designed to study the presence of carbon dioxide, water vapor, ozone, and other gases in the atmosphere at altitudes between 15 and 150 kilometers (9 to 93 miles). Still another French experiment measures radiation resulting from action of sunlight on hydrogen in the Earth's atmosphere, in the solar system, and in our galaxy. A U.S. experiment in the SL-1 atmospheric series, contributed by scientists at the Utah State University, measures airglow in the atmosphere in visible and invisible light. From these observations scientists can determine chemical processes in the atmosphere and its composition. All of the atmospheric experiments are mounted on the pallet.