STS73 Crew Video Microgravity (1995)

[Music] nine eight seven we have a go for main engine start four three two one we have booster ignition and lift up [Music] wow [Music] riding in the space shuttle when it climbs into orbit is just about the most exciting thing you could ever hope to do but we don't go into space because it's exciting we go there to learn we go there to learn about the earth below we go there to learn about the universe around us and we go there to learn about the fundamental properties of matter and living things and how the basic forces of nature affect them such as this drop of water its shape is at first controlled by surface tension but as the drop gets larger gravity takes over stretches it out and it's gone on the shuttle it's a different matter as a shuttle and everything inside it falls around the earth in its orbit gravity's effects appear to go away we call this effect microgravity and this provides us with research opportunities which are impossible to duplicate on earth hi i'm kathy thornton payload commander on united states microgravity lab 2. we call it usml2 for short our 16-day flight is dedicated to conducting 24 experiments in the study of biotechnology combustion science fluid physics and material science it's an important opportunity for scientists to gain new knowledge knowledge that can help us create better products and discover new cures for diseases in humans it's also an important opportunity for students and teachers to explore the frontiers of microgravity science in this program the crew of usml2 will show you a number of opportunities for hands-on activities you can use to learn about microgravity research we'll present our demonstrations right here in the high fidelity mock-up of our space lab module this is one of the places we go to train and practice we need to be experts in experimental procedures and how to troubleshoot problems before we lift off the activities we will demonstrate are appropriate for students of many different grade levels most require simple and inexpensive materials at the end of this program we'll show you how to get additional information about these experiments in a video showing some of the same experiments in space see you later [Music] when it's time for lunch we take cooking for granted yet this pot of boiling soup is an amazing collection of forces and interactions heat from below is conducted through the pot bottom the liquid nearest the bottom gets hot it expands becoming less dense and rises to the top against the pull of earth's gravity we call this fluid flow gravity driven convection once near the surface the heated soup cools becomes more dense and falls back to the bottom where it is heated again thus we have a continuing cycle hi i'm fred leslie a payload specialist on the usml 2 mission boiling is a process that depends on gravity to distribute heat through a pot of soup the effective but violent mixing caused by this type of buoyant flow in gravity is good for cooking but not for growing crystals for example when we try to grow crystals from solutions and molten materials flows in the liquids can lead to flaws or defects in the crystal if that crystal is destined to be used as an electronic device such uncontrolled defects can limit its performance let me show you one thing that gravity does you need a beaker or a clear jar of salt water food coloring a small vial with a string attached to it and some fresh water this vial is filled with fresh water and a few drops of food coloring i'll lower it into the beaker of salt water let's see what happens because it is less dense than the salt water the colored fresh water rises to the surface this is an example of a gravity-driven convection what do you think would happen if you lowered a vial of colored salt water into a beaker of fresh water density differences in liquids can cause fluid flows here on earth this in turn can create differences in composition or temperature when growing crystals these differences can lead to the creation of defects but what would happen if we could greatly reduce gravity's effects could we take advantage of microgravity to study the crystal growth process more carefully in space the answer is yes however there are still many things to consider while in space for example what about surface tension could differences in surface tension produce flows that can lead to crystal defects have you ever seen a water bug moving across a pond it's actually walking on the surface of the water it can do that because of surface tension surface tension results from the attraction that molecules of liquids have for each other molecules inside the liquid experience attractive forces from all different sides but molecules on the surface experience an unbalanced attractive force which causes the surface to behave like a stretch membrane this is surface tension surface tension and gravity is what causes water to form drop shapes differences in surface tension at different locations on a liquid surface can produce motion on the surface and inside the liquid this is another example of fluid flow the problem with investigating surface tension effects is that other flows driven by gravity are much more pronounced on earth gravity-driven flows can mass surface tension flows but in the microgravity of earth orbit gravity-driven flows are greatly reduced here's a simple experiment for investigating surface tension fill a petri dish or a bowl with water when the water is calm sprinkle pepper on the surface if you look closely at the pepper you will observe that the pepper isn't floating in the water it's resting on the surface the surface tension of the water keeps the pepper there now dip the end of a toothpick into some liquid soap then touch the end to the center of the dish let's watch that again in slow motion detergent in the water reduces its surface tension in the middle this difference caused molecules on the surface to be pulled towards the outside dragging the pepper along with them a surface tension driven flow this experiment touches on some of the important areas of fluid physics research we are conducting on the usml2 mission when gravity's effects are eliminated phenomenal like surface tension are much easier to investigate [Music] in microgravity the actions of fluids are remarkable we can form very large drops and observe their responses to outside forces without gravity's effects getting in the way we can study the subtle forces at work in fluids hi i'm glenn holt an alternate payload specialist on usml2 many of the experiments we perform in space deal with fluids in the effective microgravity environment that the space lab provides us we can carefully study some of the effects that are masked on the ground due to the strong force of gravity the knowledge we gain will increase our understanding of fundamental fluid physics but we will also gain some very practical knowledge on how to manage fluids effectively in space observe how water drops cling to this glass this is the property we call adhesion the water molecules in these drops actually have a greater attraction for glass than they do for themselves you can see this attraction when we pour water in a glass cylinder look at how the water has crept up a short distance against the glass wall the water has climbed upward against the pool of gravity the effect is even more pronounced when we pour colored water into this apparatus water rises the highest inside the tube with the smallest diameter that's because the capillary force can begin to overcome the weight of the water column as the diameter of the tube gets smaller here's a simple experiment you can do to study the adhesion of fluids you're going to need some simple apparatus first a small dish such as this petri dish second some microscope slides make sure they're clean you'll need some clear tape some distilled water and a protractor liquids always meet clean smooth solid surfaces in a definite angle this is called the contact angle even in earth's gravity we can measure this angle begin the activity by using tape to hinge two clean slides together this will enable you to adjust the angle the slides make with each other spread the slides to a 90 degree angle and place them in the dish the contact angle will be observed where the edges of the two slides join each other water will move upward along this seam measure and record this angle you may find it easier to make a sketch of the angle and measure it on paper readjust the wedge angle to 45 degrees and again measure and record the contact angle continue readjusting the wedge angle to make it smaller can you discover a mathematical relationship between the wedge angle of the slides and the contact angle of the water one of the important applications of this investigation is to determine the ideal geometry for vessels used to contain and transfer fluids in microgravity what's the ideal shape for a container to hold fluids in space what's the ideal shape for a vessel to transfer fluids from container to container using the capillary force does surface roughness play a role getting the answer to these and similar questions is the goal of fluid physics research on usml2 [Music] a candle flame is a wondrous thing to watch while it may look simple it is actually the manifestation of several complex chemical and physical reactions the flame begins where fuel vapor oxygen and high temperatures come together heat produced by the flame melts the candle to release more fuel the hot gases in the flame are less dense than the surrounding air gravity causes hot gases to rise and this pulls in cooler air during fresh oxygen the air movement is yet another example of gravity driven convection the upward flow of air stretches out the flame into a streamlined shape my name is katie coleman i'm a mission specialist astronaut and another member of the science crew on usml2 one of the experiments that i'm working on has to do with the combustion process in microgravity what do you think would happen if we could burn a candle in microgravity this was done on an earlier mission usml1 and we saw some very interesting results without convection currents caused by gravity the flame becomes spherical oxygen diffuses into the flame surface from the surrounding air to sustain combustion since diffusion is much less efficient for transporting oxygen than convection the flame dims and much less soot is produced we're interested in studying the combustion process in microgravity because combustion plays a key role in energy transformation air pollution global warming and transportation both here on earth and in space fire is a potential hazard in space vehicles because we can't evacuate the building like we can here on earth learning about the combustion process in microgravity can teach us a lot about combustion here on earth it can also help us learn about living in space in one of the experiments on usml2 we are studying the combustion of flammable liquids this investigation is called fiber supported droplet combustion because we use a fiber to keep the droplet from floating around in our combustion chamber the drop clings to the fiber and stays centered you can reproduce this experiment on earth by using an apparatus like this one the device consists of a fine wire twisted into several loops when the experiment is ready an electric current will be sent through the wire causing it to heat up the heat will ignite the drop of flammable liquid while it is suspended by the loops while wearing eye protection and keeping away from the wire loop press the on switch to send an electric current through the wire to ignite the drop observe how the flame begins and spreads observe the shape of the flame what is its color how long does it last how bright is it these are important questions to answer and you may find it helpful to videotape the flame so that you can slow down the action for analysis when you do this experiment on the ground you are conducting a control experiment by comparing this to the experiment conducted on usml2 we can see what effect microgravity has on the combustion process one of the important results of this experiment is that we can use the data collected to help us better understand the combustion process scientists and engineers will be able to design spacecraft and the materials and apparatus used inside that are less susceptible to fire we can also develop better fire detection strategies and emergency measures to quickly extinguish a fire should it break out advances in the understanding of fire in microgravity should help us improve fire safety in aircraft industry and the home [Music] many microgravity experiments are focused on learning about crystals crystals are an important part of our lives we've learned that crystals start out as fluids and that those fluids are strongly influenced by gravity what goes on inside fluids is of great interest to scientists it also affects crystal growth how do we go from fluids to the orderly arrangements of atoms and molecules we call the crystalline state in earlier demonstrations we examined some of the gravity-driven forces that affect fluids here's a demonstration you can do with students of all ages to dramatize the difference between gravity on earth and microgravity in space it involves small candies and many marshmallows and a plastic bag begin the activity by comparing the candy and mini marshmallows to each other how are they different and how are they similar then add equal numbers of candies and mini marshmallows to a clear plastic bag before completely sealing it up inflate it with air the next step is to simply shake the bag and observe what happens to the two different kinds of particles in the bag by shaking rapidly and then slowing down you can actually classify the different particles according to density and size the particles eventually form layers as you see here what do you think would happen if we did the same experiment in microgravity video of the results will be included in the data tape described at the end of this program [Music] winter is a great time for sports but it's very important to make sure to keep warm a case of frostbite can really ruin your day hi i'm dave matheson i'm the alternate payload specialist for crystal growth on usml2 and here's a neat way to warm your hands this is a heat pack and you can purchase this at any camping goods store or sporting goods store until you need it the chemicals inside the pack remain liquid but when your fingers are cold all you have to do is snap the metal disc inside and crystals begin forming when that happens heat is released and that can be very comforting to your hands in order for the materials to crystallize they must give up their heat of solution and that is what's warming up my hands to make this pack work the sodium acetate water solution has to be super saturated what this means can be shown with this demonstration have you ever tried to dissolve a lot of sugar in a beaker of water as we pour this in a limit is reached and no more sugar can be added and just for fun we're going to add a little bit of red food coloring we say the water is saturated with sugar however if we heat the water as we stir we can dissolve more sugar into it when we reach a point where we again cannot dissolve any more sugar into the water we have arrived at a higher state of saturation if we let the second beaker cool off the sugar remains in solution the water now contains more sugar than it normally should at this temperature it is now super saturated how do we get that extra sugar out of solution one way is to drop in some seed crystals of sugar into the water soon sugar comes out of solution and deposits on the seeds eventually large sugar crystals form we now have rock candy something similar happens with the heat packs sodium acetate is dissolved into hot water and sealed in the plastic pouch until crystallization is triggered the solution remains liquid after triggering crystals form and the heat is released what does this have to do with microgravity several of the experiments on usml 2 study crystal growth we grow crystals in microgravity free from gravity's disturbing effects then we can analyze them to understand by comparison with crystals grown on earth the effect that gravity has on the crystal growth process with heat packs you can observe the crystals grow right in front of your eyes but there's much more to these heat packs than we've observed so far the rate of crystallization and the size of the crystals can be varied by changing the initial temperature of the heat pack here's a pack at room temperature observe how it crystallizes now let's compare that to crystallization in a pack that has an initial temperature that is 15 degrees celsius higher than the first as you can see the rate of crystallization and the size of the crystals varies with the initial temperature of the pack but there's another factor involved gravity with the correct initial temperature very tiny crystals will form all through the pack being slightly denser than the solution the crystals will rain to the bottom of the pack and clump together what do you think will happen to the crystals would the same thing happen in microgravity heat packs can be used again and again just by heating up the heat pack until the crystals all dissolve you can find out more about this activity at the end of the program [Music] crystals come in many shapes sizes and colors while pretty to look at crystalline materials have many practical uses in electronics medicine and manufacturing just to name a few crystalline materials are the stuff the earth is made of and your own bodies are more than a hundred thousand proteins that crystallize when extracted one especially useful category of crystals is zeolites zeolites are porous crystals made from silicon aluminum and oxygen all of the world's gasoline supplies are produced by refineries that use zeolites to produce and purify gasoline from crude oil zeolites are also used to help purify the water used in large aquariums and they have in the past been used in many laundry detergents to help soften water to improve sudsing hello my name is al sacco and i'm a payload specialist aboard usml2 i'll be growing many different kinds of crystals on usml too one of my favorites is zeolite crystals i'll be studying the formation and growth of large zeolite crystals in the microgravity environment of low earth orbit zeolites are molecular sieves like this strainer that lets water pass through but not the spaghetti zeolites allow only molecules of certain sizes to pass through this makes the crystals very useful in many chemical processes although zeolites are used all over the world much is still not understood about their formation here's an example of zeolite a one of the zeolites that you'll be growing in your experiment as you can see like the spaghetti strainer it has specific size openings that will allow certain molecules to pass while larger molecules will not be allowed to penetrate the crystal once inside the crystal there's a large open volume and so they use the stored material that is absorbed into them typically zeolite crystals on earth are 1 10 to one-half the thickness of a human hair when we try to grow large crystals from solution gravity-driven flows disrupt crystal growth and the crystals themselves settle to the bottom of the container just like you saw with the crystals in the heat pack and grow into each other because of fluid flows and sedimentation a large number of small imperfect crystals form this limits both their ability to be characterized in their usefulness this jar contains metal shot in syrup is on a special airplane that produces microgravity for about 25 seconds by flying along a carefully controlled parabola in microgravity sedimentation is greatly reduced but look what happens when the normal gravity effects return because sedimentation effects are greatly reduced in low earth orbit the space lab aboard the space shuttle is an ideal place to learn how to grow large nearly defect-free zeolite crystals this understanding we hope will allow us to find new ways to grow large defect-free crystals here on earth you can investigate zeolites by growing them yourselves at the end of this program you will learn how to obtain the information about the specific materials quantities times and temperatures required for this investigation while wearing eye protection and gloves the required chemicals are combined in small bottles like this one a weight is attached so that the bottle can be immersed in a hot water bath over a period of several days selected bottles will be removed in samples examined for crystal growth stages be sure to document your observations with sketches and photographs you'll reach a point at which the crystals stop growing they settle and begin to grow into each other this is what we hope to eliminate in low earth orbit [Music] as you can see the activities we have presented here offer many creative opportunities for you to enhance your science and mathematics curriculum and you're probably wondering how you can get more information so you can get started during the usml2 mission nasa television will broadcast every event from launch to landing you can watch us live as we conduct our experiments if your school has a satellite dish all you have to do is aim the dish and tune the receiver details about how to do that will follow shortly if you don't have a satellite dish you can request your local cable television server to carry nasa television on one of their public service channels another way of gaining information is to contact one of the nasa teacher resource centers they have a variety of publications available for the asking one of these is the microgravity teacher's guide with activities for physical science supplementary activities specifically relating to usml2 mission will accompany the guide addresses for these centers will be shown at the end of this program probably the best source of information available to you is nasa space link this is a free electronic information system that permits you access to nasa information space images and even lesson plans via your computer a separate presentation on how to use nasa space link immediately follows this program as you log on to space link you'll find a hot topics category that's where information about our mission will be located you will learn about event schedules including a special program that you can watch where students in selected locations will be asking questions of the crew while we are doing our work in space you can also find detailed descriptions of the classroom experiments shown here and how to obtain a follow-up video that will contain orbital scenes of the science experiments in action the follow-up video will enable you to use these activities with students for years to come on behalf of the crew i'd like to thank you for joining us as we examine some of the opportunities our united states microgravity lab 2 mission offers for classroom investigation our objective here is not just to share information but to help prepare the scientists engineers and technicians of tomorrow who will continue our research into the world of microgravity [Music] [Music] [Music] space link nasa's link to classrooms across america using computer and telecommunications technology teachers and students can access a wealth of information about nasa programs and related science applications as well as materials for use in every kindergarten through postdoctoral curriculum [Music] the technology needed to use space link is becoming more common and easier to use many school systems are putting computers into classrooms businesses are sponsoring campaigns that buy computers for schools local computer stores computer clubs and parents all offer help in setting up and using computers a personal computer with the proper software and with a connection to the growing international telecommunications network opens a new world of learning opportunities for teachers and students this presentation will introduce you to what you need to use space link and the basic steps for accessing the system because of the variety of computers software and space link access methods you will see that space link is like a library with many doors but no matter which door you enter you can take advantage of nasa's resources to bring a new dimension of learning to your classroom [Music] in general there are three ways to access space link directly by telephone via personal computer with modem directly by high-speed connection to the internet and indirectly by telephone through an internet host most callers reach space link from a personal computer connected to a modem new personal computers are becoming more powerful and affordable you can access space link with older models but remember the better your computer the faster it will operate and the better it will display the graphics available on spacelink before you can call spacelink you must have communication software installed on your computer your communication software controls how you talk with space link be sure your software has vt 100 terminal emulation capability this feature is required for your computer to display the screens generated by the space link host computer before your communication software can talk to space link you must connect your computer to a modem and a telephone line with a modem you can establish your connection with spacelink simply by dialing the space link number ordinary telephone lines allow computers across the country and around the world to communicate with one another and a modem is the device that connects your computer to the phone lines a second way to access spacelink is through a direct line from your computer or facility to the internet this option requires that an internet service provider connect you directly to the internet as opposed to accessing the internet through a host computer this method provides you with the most capability but is also the most expensive of the three options the third way to access spacelink is via an internet host the internet is the world's most widely used telecommunication network an internet host is a computer system set up to provide users with access to the internet through the phone lines numerous internet host systems are available to educators you may be familiar with some of these systems which include the texas educational network the florida information resource network and quest a host computer run by nasa's ames research center three types of files are currently available in the space link library text files graphics files and software the majority of space link files are text files if your computer configuration meets minimum access standards you can access all space link text files those space links text files are useful you and your students can get more out of the system by having the capability to download spacelink's graphics files these files contain images such as clipart and photos of nasa missions and astronomical discoveries to view the graphics files you will need graphics viewing software spacelink provides graphics viewing software for several types of computers and this brings us to the third type of file available on spacelink software software files contain the graphics viewing programs mentioned before as well as educational applications such as orbital tracking programs the software you are able to use will depend on your computer configuration spacelink stores some software in compressed formats this feature decreases the time required to download the software from spacelink to your computer spacelink also provides the software tools you need to decompress the files for use with your personal computer there are five main methods to access the space link electronic library but no matter how you enter the library the same set of materials is available to everyone the five methods are direct dial modem telnet file transfer protocol or ftp gopher and world wide web here are brief descriptions of how each of these methods work first let's look at the direct dial modem method to begin you must initiate your communication software and dial space link when your modem connects to one of the space link modems the space link welcome screen appears the screen prompts you to log in and your response is the same for all users guests in lower case letters press return the important messages screen appears next this screen changes often displaying system administration notices or brief updates on where to find the latest nasa information press return next you arrive at the nasa space link electronic library menu this screen allows you to choose from among many space link information categories by pressing your arrow keys about space link educational services instructional materials nasa news nasa overview nasa projects space link frequently asked questions and space link hot topics press return to select any one of these categories and enter deeper into space link's electronic library depending on the capabilities of your computer you can then print the information store the information on your computer access graphics and download spacelink software now we'll take a look at several ways to access spacelink through the internet whether you access space link through a modem and an internet host or through a direct connection to the internet you will use one of the standard means of communicating with the internet telnet ftp gopher or world wide web let's examine what your session would look like if you access space link via telnet bring up your telnet connection and enter the space link internet address press return when you connect with spacelink the steps for accessing the electronic library are the same as we saw for accessing via modem the space link welcome screen appears the screen prompts you to log in as before so type guest press return the next screen is the important messages screen press return then you arrive at the nasa space link electronic library menu where you select one of the information categories both the direct dial modem and telnet options allow the user to view text files online ftp however transfers the space link file to your computer where they may be viewed later there are two types of ftp processes command line ftp and graphical ftp command line ftp means you enter text commands to execute space link access and file transfer processes graphical ftp means you can click on directories and file names rather than enter command lines whether you use command line or graphical ftp depends on what kind of communication software you have on your computer to execute the ftp process to keep things simple we will look just at the graphical ftp option but whether you use graphical ftp or the command line process the basic steps to access space link are the same first bring up your ftp software enter the space link internet address since spacelink is an anonymous ftp site your user id is anonymous you may use any password you like but we recommend you use your email address if you have one or guessed if you don't you are now at the nasa space link electronic library menu the ftp displays system administration folders and as you can see the same space link information categories accessed by the previous two methods are available for selection follow the instructions that came with your graphical ftp software to transfer files directly from space link onto your computer the fourth method for accessing spacelink via the internet is through gopher software there are many gopher software packages available to execute a gopher session first bring up your gopher software enter the space link internet address and press return the nasa space link electronic library menu appears select an option and go to work the final space link access option via the internet is world wide web you can choose from among several software packages that allow you to communicate with spacelink's world wide web configuration two commonly used examples are links and mosaic links is a text text-based communication software which means you will see no online graphics as you execute your session mosaic being a graphics based system allows you to click on graphic symbols or text rather than working only with text for this demonstration we will use mosaic first bring up your world wide web software enter your command to connect with the space link world wide web address known as a universal resource locator or url the space link menu graphic appears you are now ready to explore space link let's review what you need to access space link a personal computer remember the better your computer the faster it will operate and the better it will display space link graphics communication software with vt 100 terminal emulation capability a modem that allows your computer to dial space link directly through telephone lines or through an internet host computer optional graphics viewing software without graphics viewing software you can still access and view spacelink's text files however you need graphics viewing software if you wish to take full advantage of spacelink's capabilities spacelink provides graphics viewing software that can be downloaded for certain types of computers if you can arrange a direct internet connection you don't need a modem to access spacelink but you will need software with the capability to execute telnet ftp gopher or world wide web sessions [Music] if you're not familiar with computers or don't have computers at your school there are many resources available to help you get started besides your school board many businesses and community organizations have information and are willing to help you and your school take your first steps into the age of telecommunications your nasa education offices are also standing by to answer your questions space link an electronic library with many doors space link is a part of the future of telecommunications and the future of education we hope to see you on the system soon [Music] you