Between The Atom And The Star (1965)

the [Music] there are moments in the history of science when the invention of a tool suddenly accelerates the accumulation of knowledge magnification revealed worlds Beyond worlds and worlds within worlds but these worlds of the atom and the star have always been separated by a vast Gulf waiting for another tool that could bring them together with the flights of the bio satellite biologists will have the unprecedented opportunity of studying some of the forces which influence every form of life from single cells and developing eggs on up through plants and primates but which cannot be entirely studied on the ground for the bio satellite is a very special kind of biological laboratory in space where man's presence is represented by instrumentation since the acceleration of the orbiting bios satellite equals the acceleration of gravity of the earth it will be weightless now why is this important because weightlessness is a vital factor in any study of the influence of gravity on living organisms Earth in its entire history probably has known only what we call a 1G environment this means that an acceleration of about 32 ft perss per second is constantly pulling everything toward the center of the Earth all living forms have evolved under 1G naturally we're not especially aware of it because such a condition is normal in our lives by substituting centrifugal force for acceleration we can study most of the effects of gravity from one g on up the scale right here on Earth so the question can legitimately be asked what if life on Earth were to experience some other gravitational unit from 1 G down to Z zero would it have any profound effect on its development where then can we find out what will happen to living organisms if we were to remove gravity completely even out in space there is some gravity actually at the distance the bio satellite will be orbiting there's still 95% of the Earth's gravity it is the Free Fall of the satellite that gives us the weightless laboratory we need here then in the bio satellite biologists can conduct experiments on living organisms in the weightless State and then by recovering the specimens and comparing their findings to the immense amount of data they have already collected on Earth find out just what the effects are the information they get will shed light on the fundamental processes of life and have vital applications to the field of man space flight now the basic objective in doing this kind of a program is to ask questions some of the leading biologists in our country have submitted experiments to NASA they are being selected by NASA on the recommendation of outstanding biologists serving on NASA's own advisory committees and those of the National Academy of Sciences these men examine each proposed experiment to see if it is a valid experiment and equally important if if it is capable of being conducted in Flight chairing the meeting is the director of the NASA bioscience program Dr r e Reynolds and our purpose of this meeting is to review the experiments that have been selected and proposed for the bio satellite flight series here then at this meeting in the University of Colorado we'll hear a few of the questions that are being asked about life on every level of organization the first of these questions is going to be presented to us by Dr Richard young of ases research center the uh question we're asking is primarily whether gravitational field or the absence of gravitational field has a a fundamental effect on the ability of a cell to divide normally uh we're using two experimental tools with which to ask this question namely the frog egg and the sea urchin egg we feel that uh a cell is fundamentally a cell it really doesn't matter uh for the purposes of this question whether it comes from a human being a frog or a sea urchin the basic cellular phenomena we're studying here are essentially the same under normal conditions when an egg is fertilized some very Dynamic events take place in a very precise manner after a certain period of time depending on the temperature the fertilized egg divides into two cells those two into four and four into eight and so forth for many hours all the cells will remain basically the same but after a certain period of time they're going to change some will become differentiated into nerve cells some into skeletal cells or muscle cells now there's a lot we don't know about what causes these changes we'd like to know if these significant events are altered in any way by gravity so we start out with a simple and experimental concept as you can possibly come up with is the sperm which is a biological entity in itself capable of fertilizing an egg another biological entity in the absence of a gravitational field does the egg once it's fertilized proceed to divide normally without gravity or is 1g which is all life on Earth ever experiences necessary for normal development we use a sea urchin egg for one part of the experiment because we have a lot of background information on it and it can be very easily handled in the laboratory we can fertilize the eggs at will they behave in a very precise and clocklike fashion provided the environment is kept the same the seurin egg has no known specific response to gravity if we turn it over as it develops we'll still develop normally so we expect to see no profound effect caused by Zer G the second part of the experiment is to use another biological system the frog egg here we're asking the same question but unlike the sea urchin egg the frog egg requires very specific orientation with respect to gravity in order for it to divide normally you see in nature the frog egg sits on a mass of jelly once you fertilize it it will immediately Orient itself with respect to gravity now if you take this egg and turn it over so it's upside down it will simply roll over again and reorient itself if you keep it upside down however while the egg is developing something happens the egg continues to divide but forms abnormal Twins or other malformations so we have two systems with a very different response to a gravitational field on Earth we want to compare these two systems in their response to gravity and to no gravity the experiment is designed very simply during the zero g phase of the flight when the bio satellite is experiencing no gravity a simple device will inject sperm into a chamber containing the eggs and water if the eggs are fertilized at all some will be allowed to continue to develop throughout the 3-day flight others however according to plan will be killed and fixed so that later upon recovery we will study the results under the microscope we of course are interested in many more questions about cells including cells in higher plant animals our experiment is an attempt to answer the question how does a plant grow in the state of weightlessness we know that the growth and development of higher plants is gravity dependent that is a plant root grows in the downward Direction the stem or sh grows upward somehow the plant is able to sense the gravitational vector and to use the this information as a guide to its growth and development we do not fully understand how the plant senses gravity and we know even less about the way in which it uses the information to guide its morphogenetic development in some organisms we know rather clearly how gravity is sensed because these creatures have special organs to accomplish this in many invertebrates there is a sack in which there is a small small Stony ball the ball is acted on by gravity and stimulates the sides of the sack sensory hairs or cells a crayfish for example finds a pebble which he places into a hole in his head and uses it as a Gravity Sensor in this way plants do not have structures of this sort at least not on a macroscopic scale but within IND individual plant cells there must be some kind of Gravity Sensor and we would like to know what these are the experiment was designed by Dr do from the University of Minnesota and myself the experimental plant is called arabidopsis it is small and has a very short life cycle the experiment consists of a series of Chambers in which plants will be growing on uh each chamber having appropriate life support system and the plants will be started at different stages they will be followed by time-lapse photography during the course of the flight and after recovery these plants will be taken back to the laboratory and analyzed uh microscopically so that the internal anatomy uh can be revealed we'll then be able to compare the plants which were grown during the zerog experience in the Bios satellite with plants grown in the laboratory in a normal gravitational field under exactly the same conditions another factor which we know of that produces abnormalities is radiation anticipating radiation in space however is very difficult because solar flares can make the amount many times greater in local areas than you would expect these solar flares emit particles which have extremely high energy and constitute a hazard for man space flight now if you put these two factors together radiation and weightlessness you may get a combined or synergistic effect one which is even greater than you would expect one group of biosatellite experiments will be looking for genetic or heredity damage caused by weightlessness combined with radiation another group will be looking for somatic or non-inheritable effects on living organisms since solar fra radiation unfortunately is not under our control it was decided to provide an artificial radiation Source on board of the satellite the solar and Cosmic radiation will of course be measured in addition but this is expected to be low since the satellite will be flying at a relatively low altitude and geomagnetic latitude during orbit the radiation from our source will be directed onto some of the specimen this will give us the effects of radiation combined with weightlessness other specimens will be shielded from the radiation they will show the effects of weightlessness alone while the living system that we work with is a very very interesting one this is the flower Beetle a little insect maybe 3 mm long called the tribolium confusion but this little Beetle will live in dry flour a few cubic inches of air and dry flour keeps it very happy for weeks on end my colleague Dr John Slater is in charge of this experiment he has found this animal has many interesting properties and a very complicated developmental cycle first it lays eggs the eggs will produce laral stages and then they go into the pupil stage finally the finished insect emerges techniques have been developed to separate and harvest each stage by using light and screens of different sizes it's the pupe we are interested in these pupe of the tribolium are definitely gravity oriented though they don't have any known gravity sensors if you tip them over in 10 minutes they all will be back in in a normal position if they experience radiation the pupe are very sensitive to developmental damage that is later abnormalities develop in the wiing of the adults and elsewhere so here we have an insect with a quantitatively measurable defect one that will occur in a course of development as a result of radiation on the ground will radi abnormalities be worse when we combine them with weightlessness my own interest is in the daily rhythms which all organisms show in their activity I'm interested in questions about the control and the Precision of these rhythms and the extent to which they play an essential role in the physiological well-being of organisms all of these questions are of considerable interest for the space program as I hope to show you the most familiar of these rhythms is that of sleeping and waking less obvious is a similar rhythmicity and body temperature and the details of much of the chemistry of cells and tissues in general in constant conditions of light and temperature the period of these rhythms is only an approximation to that of a day we call them circadian meaning about a day in nature The Daily Light cycle controls their period to precisely 24 hours we know these rhythms to be innate to the living material most biologists in fact regard their precision and stability as also of internal origin but a few others believe these remarkable features are due to control by some so far unidentified 24-hour cycle in the Earth's environment acting as a sort of [Music] pacemaker we should be able to settle this question of an external pacemaker or Not by the satellite experiment if the Precision and stability of The rhythms do not depend on inputs with a 24-hour periodicity they will persist normally in the 90-minute Earth orbit if they do depend on them the Rhythm will be drastically affected by the conditions of the flight the test we have in mind will consist of studying the circadian rhythms of locomotion and body temperature in a hamster or a pocket Mouse during 21 days of orbital flight both The Locomotion and the body temperature will be recorded every 10 minutes and stored on tape for later analysis in a computer the question at stake is simply this does the Rhythm persist with the Precision and stability that characterizes It On The Ground there are other features of circadian rhythms of interest to Space Engineers if we suppress these circadian rhythms in some organisms if we keep tomato plants for example in constant light and temperature they get sick but the resulting damage is promptly repaired when they are again allowed to see a light or a temperature cycle the implication here is clear normal physiological functioning at least for tomatoes depends on the normal functioning of the rhythmic system if this is also true for man the further implication is equally clear for the tasks of engineering prolonged space flights for man as you know some results have already materialized from the short duration flights made by astronauts which have serious implications some of these are loss of calcium changes in blood pressure and changes in the degree of alertness or attention clearly it must be determined before before man is subjected to any prolonged space journey what the toll of the space environment may be yes uh so far with the astronauts what measurements have been made have been rather Limited in scope uh particularly in terms of the circulatory and biochemical reflection of the effects of weightlessness or on the electrical level unless we can correlate these with the previous findings that have been made so extensively in animals particularly in the monkey exactly and uh these measurements uh will permit us to interpret the otherwise limited findings that have been made on the astronauts to date now the IM of our experiment is very simple uh we want to see what happens to the blood circulation during weightlessness and uh equally important what happens to it again when the force of gravity is reapplied for example during re-entry and Recovery now an individual 5 1/2 to 6 ft tall such as the astronauts uh has quite a column of fluid represented from the top of his head to the bottom of his feet to keep the blood circulating the heart has to pump against this hydrostatic head of pressure when the individual lies down of course he reduces this head of hydrostatic pressure to a matter of a few inches instead of several feet the system no longer has to cope with the load of gravity now it's been known for many years that if you take even healthy people and put them to bed for a period of a few days or more that the blood circulation resets itself but in a way that we don't quite understand when an individual goes into a weightless State a comparable thing apparently happens this whole hydrostatic head of pressure all of this weight load on the circulation is removed and now we have an individual in this condition for a matter of weeks or even months then there's another Factor compounding the problem from the same bed rest studies and from uh reports of the short flights by astronauts we know that they will be losing calcium too perhaps because they've not been using the general weightbearing components of the body their skeleton and much of their musculature which they usually need to support themselves in a 1G environment so now the astronaut's bones are possibly more porous and brittle and he becomes less able to withstand weight the possibility of fracture becomes quite real particularly when subjected to high G forces of re-entry when he's exposed to a very heavy and severe g- loading how weak will his bones be can his circulatory function now cope with this added burden we don't know and we must find out so that's what we'll try to do to make some quantitative measurements to see what happens to the blood circulation in a fully conscious primate we'll measure the usual things heart rate blood pressure but that's not enough we also want to measure the quantity of blood the heart pumps out per minute the actual volume flow of blood and we'll collect all of the urine that the monkey produces during this period of time analyze it and make a judgment as to the kind of bi chemical adjustments that have occurred for instance we'll be able to measure its calcium loss and determine exactly what has happened to the skeletal system well another area that we must investigate is the effect of weightlessness on the central nervous system and this is particularly true where weightlessness is combined in the spacecraft with isolation and confinement we already know from work that we've done that the effect of isolation alone is very profound on judgment and judgment capability and when isolation is combined with weightlessness and with confinement the effects on the central nervous system may be so profound that we must investigate these problems specifically now the astronut doesn't have to have very much all he has to do is not to be able to think very fast and he's lost apparently Detachment at the time of re-entry is of the greatest concern the man may not recognize that anything un usual has happened at all this is one of the most serious dangers because the changes in his degree of alertness are very subtle the attention of physiologists in the last 30 years has been intensively directed to an investigation of brain mechanisms we surgically implant electrodes into the brain of the animal and this in no way hurts him or impairs his ability to function and then we can look at certain electrical patterns called brain waves coming from the brain and from many years of inves ation we can come to know what levels of consciousness they reveal now it would be an exaggeration to say that these studies are complete but there is enough background information on the electrical activity of the brain so that we can relate this activity to the mechanisms in the brain that control sleep and wakefulness and unconsciousness and more recently to the finer aspects of focusing of attention the performance of learned tasks and the ability to remember from a behavioristic point of view then we will give the animal a task to perform during the flight such as for example pressing a lever to get his food or coordinating his eye and hand movements in grasping a pellet from a moving window we will carefully test this coordination between eye and hand movements it is something which in a weightless state is likely to undergo quite significant deterioration and may not necessarily recover well if he doesn't press the lever at all you can make assumptions that he has forgotten how to work the panel but he might be in some unconscious State due to some environmental change if the animal is not conscious we want to know why and without brain activity being recorded we would never know we plan a very rigorous analysis of the best possible portions of the data during the flight from the most representative areas of the brain and this data will be fed into a computer which will give us a continuous microscopic look at the brain waves over a period of 30 days you may be wondering just how we can keep these animals alive for as long as 30 days and then recover them well as you know uh designing the spacecraft to last uh 30 days is uh no problem but uh keeping them alive up there for 30 days uh course is the problem now let's go to the cape in our minds and look at the mission profile to see what phas of the journey may give us trouble we're going to be putting the biosatellite into a circular orbit around the Earth very close to the equator and we're using an extremely high portion of flight proven techniques and Equipment throughout the project we'll be using the improved thrust augmented Delta launch vehicle remember uh there's one major requirement here to keep the spacecraft at z g for 95% of the time the effective gravitational force shall not exceed 1 100,000th of a g well with these animals we're going to have to know exactly how they feel and do it all with instruments and we've got to do more than merely keep them alive we have to keep the total environment up there just the same as it was in the control experiment on the ground to do this we've designed the spacecraft in two B B sections one section is the adapter it contains all the equipment required to keep the specimens alive and to keep the spacecraft in operation before re-entry we drop the adapter off in [Music] space after the retr fire aerodynamic forces take over and point the heat shield toward the line of flight what is the effect of changes in gravity on the processes of living organisms will a cell divide and differentiate normally how will weightlessness affect plant growth be radiation combined with weightlessness produce unanticipated hazards for man's space flight is it true after all that the Precision and the stability of circadian rhythms in fact depend on inputs which we do not understand associated with the Earth's rotation after 30 days of weightlessness how weak will a man get how much calcium will he lose well it affect his judgment these are only a few of the questions and this little biosatellite capsule only 40 in in its diameter cone base with an overall length of 33 in is expected to get the answers answers in the form of data facts for new biological theories that will help to bridge the worlds between the atom and the [Music] star for