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                           THE ELECTRONIC JOURNAL OF
                   THE ASTRONOMICAL SOCIETY OF THE ATLANTIC

                      Volume 5, Number 3 - October 1993

                         ###########################

                              TABLE OF CONTENTS

                         ###########################

          * ASA Membership and Article Submission Information

          * Echoes of the Distant Bang - Don Barry

          * Logistics and Operations Implications of Manual Control of
            Spacecraft Docking Maneuvers - Adam R. Brody

          * Celestial Favorites of Autumn - Bruce Bowman

                         ###########################

                         ASA MEMBERSHIP INFORMATION

        The Electronic Journal of the Astronomical Society of the Atlantic
    (EJASA) is published monthly by the Astronomical Society of the
    Atlantic, Incorporated.  The ASA is a non-profit organization dedicated
    to the advancement of amateur and professional astronomy and space
    exploration, as well as the social and educational needs of its members.

        ASA membership application is open to all with an interest in
    astronomy and space exploration.  Members receive the Journal of the
    ASA (the JASA is a hardcopy sent through United States Mail and is not 
    a duplicate of this Electronic Journal) and the Astronomical League's 
    REFLECTOR magazine.  Members may also purchase discount subscriptions
    to ASTRONOMY and SKY & TELESCOPE magazines.

        For information on membership, you may contact the Society at any
    of the following addresses:

        Astronomical Society of the Atlantic (ASA)
        P. O. Box 15038  
        Atlanta, Georgia  30333-9998
        U.S.A.

        asa@chara.gsu.edu         (For ASA issues)
        klaes@verga.enet.dec.com  (For EJASA issues)

        ASA BBS: (404) 321-5904, 300/1200/2400 Baud

        or telephone the Society Recording at (404) 264-0451 to leave your
    address and/or receive the latest Society news.

        ASA Officers and Council -

        President - Eric Greene
        Vice President - Jeff Elledge
        Secretary - Ingrid Siegert-Tanghe
        Treasurer - Mike Burkhead
        Directors - Becky Long, Tano Scigliano, Bob Vickers
        Council - Bill Bagnuolo, Michele Bagnuolo, Don Barry, Bill Black, 
                  Mike Burkhead, Jeff Elledge, Frank Guyton, Larry Klaes, 
                  Ken Poshedly, Jim Rouse, Tano Scigliano, John Stauter, 
                  Wess Stuckey, Harry Taylor, Gary Thompson, Cindy Weaver, 
                  Bob Vickers


                             ARTICLE SUBMISSIONS

        Article submissions to the EJASA on astronomy and space exploration
    are most welcome.  Please send your on-line articles in ASCII format to
    Larry Klaes, EJASA Editor, at the following net addresses or the above
    Society addresses:

        klaes@verga.enet.dec.com
        or - ...!decwrl!verga.enet.dec.com!klaes
        or - klaes%verga.dec@decwrl.enet.dec.com
        or - klaes%verga.enet.dec.com@uunet.uu.net

        You may also use the above addresses for EJASA back issue requests,
    letters to the editor, and ASA membership information.

        When sending your article submissions, please be certain to include
    either a network or regular mail address where you can be reached, a
    telephone number, and a brief biographical sketch.

        Back issues of the EJASA are also available from the ASA anonymous 
    FTP site at chara.gsu.edu (131.96.5.29).  Directory: /ejasa

                                DISCLAIMER

        Submissions are welcome for consideration.  Articles submitted,
    unless otherwise stated, become the property of the Astronomical
    Society of the Atlantic, Incorporated.  Though the articles will not
    be used for profit, they are subject to editing, abridgment, and other
    changes.  Copying or reprinting of the EJASA, in part or in whole, is
    encouraged, provided clear attribution is made to the Astronomical
    Society of the Atlantic, the Electronic Journal, and the author(s).
    Opinions expressed in the EJASA are those of the authors' and not
    necessarily those of the ASA.  No responsibility is assumed by the 
    ASA or the EJASA for any injury and/or damage to persons or property 
    as a matter of products liability, negligence or otherwise, or from 
    any use of operation of any methods, products, instructions, or ideas 
    contained in the material herein.  This Journal is Copyright (c) 1993
    by the Astronomical Society of the Atlantic, Incorporated.


                           ECHOES OF THE DISTANT BANG

                                  by Don Barry

       In that tumultuous era following Edwin P. Hubble and Slipher's
    discovery of the recession of distant galaxies, astronomer and priest
    Georges Lemaitre attempted to mock the newly-minted expansionist view
    of the Universe.  He asked what happened to start this vast panorama:
    A "Big Bang?!"  Much to his chagrin, the theory was increasingly
    accepted and his satirical term stuck. 

        Today, some sixty years after the first glimpses of the structure
    of a Universe which is ever expanding, sending a horizon of visibility
    off into the distance at the speed of light, space-based instruments
    are now measuring the faint mottlings in the structure of that
    fantastically hot cosmic egg, now reddened and cooled by recession
    from us into the frigid 3 degrees Kelvin (-460 degrees Fahrenheit, 
    or -270 degrees Celsius) microwave background radiation. 

        Penzias and Wilson discovered these microwaves, a sort of cosmic
    static, through sensitive antennae in their work at Bell Laboratories
    in the 1960s.  What was earlier thought to be the noise of pigeon
    infiltration in their reception horns became almost clinching evidence
    for an earlier plasma age of the Universe in which all matter, com-
    pressed and heated, cooled into suddenly transparent hydrogen and 
    helium. 

        We can follow the Universe backwards through time, applying
    well-known physical laws governing the motion and thermodynamics (heat
    flow) of the bodies we now observe and study.  As time regresses, we
    find that celestial bodies moved closer together and the Universe
    became hotter.  Some fifteen billion years previous to now, galaxies
    disassociated into hot gaseous clouds.  These clouds merged into a
    thickening ocean of gas, and, as the temperature reached a critical
    point, atoms released their electrons and the Universe became opaque. 
    Beyond this, the ripples that were galaxies smoothed themselves until
    at quintillionths of one second after genesis, when the Universe was
    scarcely the size of a proton, the ripples merged into the sea of
    native fluctuations in space. 

        Looking out into the most distant corners of the Universe, we also
    look back in time.  As a result, we have access to a sort of "time
    machine" to see a historical record of the Universe past and distant. 
    As we look further, we also look across the expanse of intervening
    expanding space, which dilutes and dims the further images.  Shortly
    beyond the most distant quasars and galaxies, we reach the opaque
    wall.  Looking in all directions, we see adjacent parts of the
    Universe and encounter the cosmic fireball itself.  This is the
    microwave background radiation. 

        The COBE (COsmic Background Explorer) satellite has probed 
    these embers of the original flame since its launch in 1990, making
    increasingly more precise measurements of the temperature of the
    Universe in all directions.  A special instrument, the Differential
    Microwave Radiometer, has repeated many measurements from each area 
    of the sky.  After much processing and averaging, it can now be said
    with certainty that there is a lumpiness in temperature of some one
    millionths of one degree at various magnifications of view.  These 
    are the early ripples that seeded development of galaxies, stars, 
    and eventually, ourselves. 

        All scientific theories must make certain tests of themselves
    which are capable of proving them false:  An untestable proposition 
    is properly outside the realm of science.   Various modifications of
    the Big Bang predict different levels of fluctuation in the early
    fireball, but most show these fluctuations to be present at various
    scales and amplitudes.  Now they have been measured and many versions
    of the Big Bang must fall.  The versions that remain will make still
    more definite predictions, and these too will one day be scrutinized. 

        In the early spring of 1992, cosmologist David Schramm called a 
    special meeting of cosmologists with an extraordinarily unusual proviso:  
    By invitation only.  At this one-day meeting held in Irvine, California,
    the most noted researchers in each subfield of cosmology gave a brief
    review of the current state of the art, with an overview of predictions 
    made by each of the various models of the very early Universe. 

        It became clear to the attendees that specific results from COBE
    were in the mill, but a formal announcement was delayed until the April, 
    1992 meeting of the American Physical Society. Since the release, some 
    have compared this discovery in importance to the recession of the 
    galaxies themselves.  Others have merely noted how it further refines 
    the science and permits a new era of more restricted speculation to 
    begin. 

        As one astronomer has noted:  "Crazy days indeed!"

        About the Author -

        Don Barry, former ASA President and Charter Member, is an
    astronomer with the Center for High Angular Resolution Astronomy
    (CHARA).  Don has written his Ph.D. thesis on measuring the relative 
    luminosity of very close double stars.  Don's professional interests 
    include optical interferometry, binary astrometry and photometry, and 
    innovative instrumentation.  An active amateur as well, Don's interests 
    include telescope making, antique instruments, and fostering amateur-
    professional collaborations.  Don has recently returned from a trip 
    to Canada and Alaska.  His Internet address is: don@chara.gsu.edu

        Don is the author of the following EJASA articles:  

        "Astronomy Week in Georgia" - August 1989

        "Profiles in Astronomy: Albert Whitford" - September 1989; an
    interview with Edmund Dombrowski and Sethanne Howard

        "Alar Toomre: Galactic Spirals, Bridges, and Tails" - October 
    1989; an interview with Edmund Dombrowski and Sethanne Howard

        "Observing the Wreaths of Winter" - December 1989

        "The Mayall Four-Meter Telescope" - May 1990

        "A Southern Travel Diary: An Observer's Tale" - August 1990

        "Saturn's Great White Spot" - February 1991

        "The Hyades: A Star Cluster Rich in Myth and Astronomy" - June 1992;
    with Ken Poshedly

        "Tales of the Double Stars" - November 1992


           LOGISTICS AND OPERATIONS IMPLICATIONS OF MANUAL CONTROL OF
                           SPACECRAFT DOCKING MANEUVERS 

                                  Adam R. Brody
               Senior Aerospace Engineer/Experimental Psychologist
                                Sterling Software
                            NASA Ames Research Center
                       Moffett Field, California, 94035-1000
                                     U.S.A.

              Copyright (c) 1993 by Sterling Software.  Published 
              by the International Astronautical Federation (IAF), 
              with permission.

        The following paper was presented at the AIAA/SOLE Fourth Space 
    Logistics Symposium.

        Abstract

        Long-term operational issues are major drivers for future space
    activities such as the Moon and Mars missions described in the Space
    Exploration Initiative (SEI).  The Russians have tremendous experience
    with long-duration space missions in Earth orbit - they have launched
    no fewer than seven successful space stations - but the United States
    space program needs this experience.  Obtaining long-term operational
    experience is one of the goals of Space Station FREEDOM (now possibly
    called ALPHA).  With a better understanding of mission logistics, the
    United States will increase the benefits it realizes from its space
    program. 

        Introduction

        The importance of logistics in spacecraft control, for example,
    arises in the management of resources such as time and fuel.  Time 
    and fuel are both at a premium in on-orbit activities.  Effective
    handling of both is necessary for a productive, efficient, and viable
    space program.  Since docking operations will be under manual control
    in the U.S. space program, a better understanding of the associated
    human factors required to achieve an improved estimation of the cost
    of on-orbit logistics is needed.  Flight parameters such as braking
    gates and control modes, thruster characteristics such as magnitude
    and number, docking port location, center of mass offsets, allowable
    impact velocity, etc., all affect the ability of a human controller to
    perform a maneuver.  They also influence the mission duration and fuel
    consumption.  All of these issues relate to logistics.  Experimental
    support leading to the expansion of the operational flight envelope
    will prove very important for the logistics of future space operations. 

        Logistics planning is a very important aspect of mission planning.
    Life cycle costs will exceed design and development costs in the long-
    term missions being planned for the future.  An investment in research 
    now will have large payoffs over the long-term. 

        The design of docking maneuvers affects the design of hardware. 
    For example, there is a tradeoff between the mass of the docking
    fixture on a space station, or satellite, and the amount (mass) of
    fuel that will be consumed by a vehicle docking with it. More fuel
    will be consumed in performing the precise maneuvering required to
    dock with a fragile docking fixture than would be required to dock
    with a more robust one.  Since launch costs are directly proportional
    to launch mass, hardware designers are incessantly endeavoring to
    reduce mass potentially at the expense of increased support costs over
    an operational lifetime.  However, over an operational lifetime,
    operational costs may be elevated as a result of the increased fuel
    consumption necessary to dock with a lighter, more fragile target. 

        Also, as in Earthbound environments, with spacecraft docking there
    is a logistics tradeoff between mission duration and fuel consumption.
    Shorter mission durations, achievable by faster average velocities,
    must be paid for with increased fuel consumption.  The non-linearities
    associated with orbital mechanics effects tend to make this tradeoff
    non-intuitive, however. 

        Research

        The first author conducted a study to evaluate this fuel and time
    cost tradeoff.  Simulated docking maneuvers were performed at approach
    rates varying from 0.3 meters per second (m/s) to 9.0 m/s from an
    initial range of 304.8 meters.  The cost values in 1984 dollars were
    $3,500 per kilogram of fuel and $439,000 per day of astronaut time. 
    These values translated into approximately $6,000 per m/s of velocity
    increment and $5 per second of crew time.  At these rates, with the
    cost of fuel so high, mission cost was predominantly driven by fuel
    cost and the savings in time achieved by traveling faster did not
    compensate for the increased cost of fuel.  Only in the lowest
    velocity case were the costs comparable (See Figure 1 and Ref. 1).

        Figure 1: Cost versus Initial Velocity

        There are a number of situations that can alter this cost
    equation, however.  The cost of fuel can possibly be decreased by
    using waste water, or by combining planetoidal hydrogen with lunar
    oxygen.  This would decrease the relative cost of fuel, possibly
    enabling a least time solution to yield a least cost solution. 
    Another circumstance is a rescue situation where time becomes more
    important and the cost of time jumps tremendously.  Thus, the cost
    equation relating time and fuel is variant and this must be accounted
    for in long term operations. 

        Another logistics issue involves the inverse relationship between
    the number of burns and the fuel consumption in a docking when the two
    vehicles have zero initial relative motion.  In general, the fewer the
    number of burns in a docking maneuver, the more efficient the burns
    and consequently the lower the fuel consumption.  For a target in the
    same orbit as the chaser, the two-burn (one starting, one stopping)
    maneuver is the most fuel efficient.  This is described in the
    following figure, which compares the same mission performed with one
    large "hop" and four small "hops".  Although the single hop mission is
    more fuel efficient, multiple hop missions are generally encouraged so
    that the target is always kept in the field of view.  This demonstrates 
    a tradeoff between efficiency, and a mission requirement to maintain 
    target visibility throughout the mission (See Figure 2). 

        Recent research in the Space Station Proximity Operations
    Simulator at NASA Ames Research Center revealed that docking
    operations can be safely performed rapidly if necessary (Refs 2-6). 
    In several studies, simulated remotely piloted docking operations from 
    an initial range of 304.8 meters on the -V-bar (minus velocity vector)
    were successfully completed in two to three minutes.  This is much
    faster than current flight guidelines prescribe (Refs 7-8).  This
    rapid docking capability will help to ensure the safety of a
    crewmember, vehicle, or satellite low on consumables.  "An
    understanding of the fastest safe-docking technique will always be
    necessary for contingencies that will inevitable arise (Ref. 4)." 
    This will also facilitate managing a high-traffic area around the
    space station among other benefits. 

        Figure 2: Approach Trajectories

        A subsequent study demonstrated that a rapid docking capability 
    is robust enough to survive an anomalous thruster firing during the
    approach (Ref. 4).  An unexpected thruster firing during the simulated
    docking caused the vehicle to travel out of the orbital plane.  No
    statistically significant velocity effect was found indicating that
    slower velocities were safer. 

        A comparison of acceleration control and pulse control was
    performed to evaluate the inference that astronauts are instructed to
    use pulse mode for fuel conservation reasons.  The study revealed that
    pulse control was not inherently more fuel efficient than acceleration
    control.  In pulse mode, more fuel was used to achieve lower mission
    durations than with acceleration control.  This result is important
    for long-term logistics planning (See Figure 3).

        Another result of the acceleration/pulse study is an interesting
    relationship between range and X (axial) delta V.  Delta V increased
    with initial range (See Figure 4).  "The direct relationship between
    range and X delta V is not intuitive.  Unlike conventional environments 
    such as air, sea, and land, the force of drag involved in a docking 
    maneuver in orbit is negligible.  Energy need not be expended to 
    maintain velocity on orbit.  Rather, more fuel was consumed because 
    the greater ranges enabled higher approach velocities.  This increased 
    fuel consumption prevented the mission duration from increasing linearly 
    with range as would happen if average approach velocity were the same 
    regardless of initial range." (Ref. 9) 

        Figure 3: Mode Main Effects

        Figure 4: Velocity Increment Components versus Range

        The main effect of mission duration by mode was not preserved 
    in the second half of the data.  This inconsistent main effect, or
    asymmetrical transfer, is important for mission logistics planning. 
    It indicates that previous experience will affect current and future
    performance and this effect must be understood and quantified so 
    that plans can be made accordingly (See Figure 5). 

        The results from these studies apply to Moon and Mars orbital
    operations in addition to Earth orbital operations.  Most evolutionary
    scenarios involve transfer vehicles and stations in orbit around the
    Moon and Mars.  Ascent vehicles will rendezvous and dock with these
    stations enroute to Earth.  Supply and personnel vehicles from Earth
    will also dock with orbiting stations.  Descent spacecraft will ferry
    the crew and supplies down to the planet.  Furthermore, logistics
    planning and support are more important for the Moon and Mars than
    Earth orbital missions because of the greater distances and associated
    time delays. 

        Figure 5: Asymmetrical Transfer

        To determine the amount of supplies for a mission, an accurate
    estimation of the logistics requirements is needed.  If the actual
    versus theoretical minimum rendezvous propellant usage from the GEMINI
    program of the 1960s is any indication, an accurate estimation could
    be difficult to achieve.  The ratio of actual:minimum varied from 1.52
    to 4.28 for the ten performed rendezvous operations (See Figure 6 and
    Ref. 10).  This uncertainty could be very detrimental to mission
    planning.  Life-cycle costs would be unnecessarily high if a fuel
    safety factor of over four were always used when a more moderate one
    of two would be sufficient.  "Research into the manual control aspects
    of rendezvous maneuvers will help reduce both the absolute value and
    the variance of the actual/theoretical fuel consumption ratio." (Ref. 9) 

        A number of computer-based tools are available for planning
    missions such as docking operations (Refs 11-16).  Use of one of these
    tools would greatly aid the mission operations planners in determining
    logistics requirements such as time and fuel.  This information would
    then be used to allocate the appropriate amount of time, and the
    necessary fuel. 

        Figure 6: Comparison between minimum and actual propellant usage
    in GEMINI rendezvous operations.  Produced from the data in Ref. 10. 

        Summary

        The implications of logistics and operations on the manual control
    of spacecraft docking are clear.  Better understanding of the associated 
    issues will yield a safer and more efficient, and productive space 
    program.  Continued research is advocated to achieve this end. 

        References

        1.  Brody, A. R., "Spacecraft Flight Simulation: A Human Factors
            Investigation into the Man-Machine Interface Between an 
            Astronaut and a Spacecraft Performing Docking Maneuvers and 
            Other Proximity Operations", Unpublished Master's Thesis, 
            Massachusetts Institute of Technology (MIT), Cambridge, MA, 
            April 1987.  See also NASA CR-177502, September 1988. 

        2.  Brody, A. R., "The Effect of Initial Velocity on Manually
            Controlled Remote Docking of an Orbital Maneuvering Vehicle 
            to a Space Station", American Institute of Aeronautics and 
            Astronautics (AIAA), Washington, D.C., Paper 89-0400, January 
            1989. 

        3.  Brody, A. R., "Recovery from an Anomalous Thruster Input During 
            a Simulated Docking Maneuver", Fourth Annual Workshop on Space
            Operations Applications and Research (SOAR '90), NASA CP-3103, 
            Vol. 2, National Aeronautics and Space Administration, Washington, 
            D.C., 1990, pages 557-560. 

        4.  Brody, A. R., and Ellis, S. R., "Effect of an Anomalous Thruster 
            Input During a Simulated Docking Maneuver", JOURNAL OF SPACECRAFT 
            AND ROCKETS, Vol. 27, No. 6, Nov./Dec., 1990, pages 630-633. 

        5.  Brody, A. R., "Evaluation of the `0.1% rule' for Docking
            Maneuvers", JOURNAL OF SPACECRAFT AND ROCKETS, Vol. 27, No. 1, 
            1990, pages 7-8. 

        6.  Brody, A. R., "Remote Operation of an Orbital Maneuvering
            Vehicle in Simulated Docking Maneuvers", Third Annual Workshop 
            on Space Operations Applications and Research (SOAR '89), NASA 
            CP-3059, National Aeronautics and Space Administration, 
            Washington, D.C., July 1989, pages 471-475. 

        7.  Oberg, J. E., "Rendezvous and Proximity Operations Handbook",
            NASA Lyndon B. Johnson Space Center Mission Operations Directorate
            Flight Design and Dynamics Division, JSC-10589, May 1988. 

        8.  Sedej, D. T., and Clarke, S. F., "Rendezvous/Proximity Operations 
            Workbook RNDZ 2102",  NASA Lyndon B. Johnson Space Center Mission 
            Operations Directorate Training Division Flight Training Branch, 
            1985. 

        9.  Brody, A. R., and Ellis, S. R., "A Comparison of Acceleration
            Control and Pulse Control in Simulated Spacecraft Docking 
            Maneuvers", American Institute of Aeronautics and Astronautics, 
            91-0787, Washington, D.C., January 1991. 

       10.  Evans, W. B., and Czarnik, M. R., "Summary of Rendezvous
            Operations", GEMINI Summary Conference, NASA SP-138, Manned 
            Spacecraft Center, Houston, TX, February 1-2, 1967, pages 7-19. 

       11.  Ellis, S. R., and Grunwald, A. J., "The Dynamics of Orbital
            Maneuvering: Design and Evaluation of a Visual Display Aid for 
            Human Controllers", Proceedings of the FMP Symposium on Space 
            Vehicle Flight Mechanics, AGARD-CP-489, Luxembourg, 1989, 
            pages 29-1 to 29-13. 

       12.  Grunwald, A. J., and Ellis, S. R., "Interactive Orbital Proximity 
            Operations Planning System", National Aeronautics and Space 
            Administration, TP 2839, Washington, D.C., November 1988. 

       13.  Grunwald, A. J., and Ellis, S. R., "A Visual Display Aid for
            Orbital Maneuvering: Experimental Evaluation", JOURNAL OF 
            GUIDANCE AND CONTROL.

       14.  Brody, A. R., "EivaN: A Forward-Looking Interactive Orbital
            Trajectory Plotting Tool for Use with Proximity Operations 
            (PROX OPS) and Other Maneuvers Description and User's Manual", 
            National Aeronautics and Space Administration, NASA CR-177490, 
            Washington, D.C., April 1988. 

       15.  Brody, A. R., "EivaN: An Interactive Orbital Trajectory
            Planning Tool", National Aeronautics and Space Administration, 
            NASA CR-185888, COSMIC Software Catalog, Washington, D.C., 1990. 

       16.  Brody, A. R., "EivaN: An Interactive Orbital Trajectory
            Planning Tool", JOURNAL OF SPACECRAFT AND ROCKETS, Vol. 27, 
            No. 6, 1990, November/December, pages 681-683. 

        About the Author -

        Adam R. Brody received S.B. and S.M. degrees in Aeronautics and
    Astronautics from the Massachusetts Institute of Technology (MIT) in 
    Cambridge, Massachusetts, and a diploma as a member of the founding
    conference of the International Space University (ISU).  Adam also
    received his M.A. degree in Psychology from San Jose State University
    in California. 

        Adam is a senior aerospace engineer/experimental psychologist 
    for Sterling Software, Palo Alto, California.  Among the NASA Ames
    Research Center organizations with which he has worked are the
    Centrifuge Facility Project Office, Human Interface Research Branch,
    EVA Systems Branch, and the Aerospace Human Factors Research Division.
    Adam is the author of over thirty-five research papers on various
    topics relating to performance aspects of humans in space.  Adam
    pioneered a comprehensive study of the human factors and manual
    control aspects of orbital flight and he developed the Space Station
    Proximity Operations Simulator at Ames for his studies.  He also
    initiated a research program to quantify EVA rescue requirements, and
    created of an orbital trajectory planning tool for the Macintosh
    computer system. 

        Adam's research interests include the human factors and manual
    control requirements of space station proximity operations and other
    manned space flight operations.  Recent work includes development 
    and simulation of an EVA self-rescue technique using the Virtual
    Interactive Environmental Workstation (VIEW).  Currently, he serves 
    as the human factors expert on the systems engineering staff of the
    Centrifuge Facility Project Office at Ames, where he developed the
    Payload Resource In Space Monitor (PRISM) for tracking resources on
    the FREEDOM space station.  He is currently using object-oriented
    rapid prototyping to develop software requirements for the space
    station facility. 

        Adam is a member of the Space Operations and Support Technical
    Committee of the American Institute of Aeronautics and Astronautics,
    where he is chairman of the Human Factors, Automation and Robotics
    Sub-committee.  He is also a member of the National Air and Space
    Museum, the Union of Concerned Scientists, a founding sponsor of the
    CHALLENGER Center, and a charter member of the Technology Center of
    Silicon Valley.  His biography is listed in Personalities of America,
    the Dictionary of International Biography, Who's Who of Emerging
    Leaders in America, Who's Who Among Young American Professionals, 
    and Who's Who in the West. 

        Adam is the author of the following EJASA articles:

        "Soviet Spacecraft Docking Experience" - October 1992 

        "Further Analysis of EVA Self-Rescue Data" - December 1992

        Adam may be reached through the Internet at either: 

        Adam_Brody@qmgate.arc.nasa.gov or brody@eos.arc.nasa.gov 


                          CELESTIAL FAVORITES OF AUTUMN 

                                 by Bruce Bowman

        Autumn weather in the Northern Hemisphere is generally very
    pleasant for viewing the night sky.  Here are a few celestial objects 
    to be added to any favorite autumn non-Messier list.  In addition to 
    these objects, you might try the better known NGC 40, 7008, 6543, 891, 
    and the Helix.

        NGC404:  This fairly bright object is right in the field of Beta
    Andromedae.  It is relatively bright at eleventh magnitude, but the
    glare of Beta may cause some viewing difficulties.  Use fairly high
    power on your telescope and move Beta out of the field.  You will not
    have any trouble locating 404, but seeing it may be a problem!

        NGC1501:  This planetary nebula in Camelopardalis is quite large
    as planetaries go.  It is perfectly spherical with an even brightness
    throughout.  A good object; typically a winter observation, but far
    enough north to be visible now as well, if your northeastern sky is
    not too light-polluted. 

        NGC7789:  One of the richest open clusters, it approaches globular
    cluster status in the number of stars, but its Hertzsprung-Russell
    (H-R) diagram gives it away as an open cluster.  Very rich and
    extremely large, it is composed of fairly faint stars and therefore
    may be difficult to resolve in small telescopes.  An instrument of
    twenty centimeters (eight inches) or larger should show over one
    hundred stars. 

        NGC7510:  Another interesting open cluster, composed of about ten
    bright stars and some fainter ones as well.  Interesting for its shape,
    which is a rather regular if short isosceles triangle. 

        NGC6939/6946:  An open cluster in Cepheus with a faint, face-on
    galaxy very close to it.  An interesting study of depth of field, as
    the cluster is substantially closer than the galaxy.  There has been
    some indication that NGC6946 may be part of the Local Group of galaxies, 
    of which the Milky Way is a member.  You will probably need at least 
    a twenty-centimeter (eight-inch) telescope for this galaxy, but the 
    cluster should show in a ten-centimeter (four-inch) instrument under 
    good skies. 

        NGC7023:  A complex of reflection nebulosity around a seventh
    magnitude star in Cepheus.  You may need averted vision to see it. 
    Look for a blue haze surrounding the star.  Your nebular filter will
    not help. 

        NGC246:  A very large planetary nebula in Cetus, a little
    elongated and perhaps a little different from the planetaries you 
    have been viewing.  Try it out! 

        NGC7331:  Another one of the best galaxies in the autumn evening
    sky.  Scan north of Eta Pegasi to find it nearly at the zenith at
    about nine p.m..  This object will show structure at high power, and
    it takes magnification pretty well with its high surface brightness. 
    Do not miss this one the next time you go out.  This object is
    occasionally used as an example of what the Milky Way might look 
    like if we were able to view our galaxy from intergalactic space. 

        NGC55:  From the deep south, this object has to rate up there 
    with NGC7331 and perhaps even NGC253 as a prototypical barred-spiral
    galaxy.  From my back yard, it is difficult but extremely large:  An
    edge-on barred spiral with what appears to be a gap in the nebulosity.

        NGC869/884:  Also known as H and Chi Persei, the Double Cluster is
    renowned as an excellent sight.  Easily visible with the unaided eye,
    this object is quite impressive even in binoculars.  Your telescope
    will need a wide-field ocular to see both clusters at the same time,
    for 869 is a little richer in stars than 884 is.  Look for color in
    the stars:  One of the two has a bright red star right in the center. 
    Can you tell which one? 

        References and Further Reading - 

        Bishop, Roy L., OBSERVER'S HANDBOOK, The Royal Astronomical 
         Society of Canada (RASC)

        Burnham Jr., Robert, BURNHAM'S CELESTIAL HANDBOOK (three volumes), 
         Dover Books, Mineola, New York, 1978

        Menzel, Donald H., and Jay M. Pasachoff, FIELD GUIDE TO THE 
         STARS AND PLANETS, Houghton Mifflin Company, Boston, 1983 

        Moore, Patrick, EXPLORING THE NIGHT SKY WITH BINOCULARS, 
         Cambridge University Press, 1986

        Murdin, Paul, CATALOGUE OF THE UNIVERSE, Crown Publishers, 1979

        Related EJASA Articles -

        "Alar Toomre: Galactic Spirals, Bridges, and Tails", an interview 
    by Sethanne Howard, Edmund Dombrowski, and Don Barry - October 1989

        "Pegasus: Winged Horse of Autumn", by Brian Mason - September 1990

        "Andromeda, Lady of Fall", by Brian Mason - November 1990

        "Stephan's Quintet", by Bob Bunge - February 1991

        "Aperture Arrogance", by Eric Greene - March 1991

        "Astronomy and the Family", by Larry Klaes - May 1991

        "Telescopes: A Novice's Guide", by Steven M. Willows - March 1992


      THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC

                         October 1993 - Vol. 5, No. 3

                           Copyright (c) 1993 - ASA

