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SPACE Digest                                     Volume 11 : Issue 216

Today's Topics:
        Electronic Journal of the ASA, Vol. I, No. IX
----------------------------------------------------------------------

Date: 3 Apr 90 03:41:28 GMT
From: mephisto!eedsp!chara![e-mail]  (Donald J. Barry)
Subject: Electronic Journal of the ASA, Vol. I, No. IX


                        THE ELECTRONIC JOURNAL OF
                THE ASTRONOMICAL SOCIETY OF THE ATLANTIC

                     Volume 1, Number 9 - April 1990

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

                            TABLE OF CONTENTS

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

         * ASA Membership/Article Submission Information

     * Amateur Astronomy in Spain - Jordi Iparraguirre

         * The Cosmic Distance Scale - Eric Greene

         * Milton Updegraff, Astronomer - Darwin Christy

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

                       ASA MEMBERSHIP INFORMATION

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

        Membership application is open to all with an interest in
    astronomy and space exploration.  Members receive the ASA Journal
    (hardcopy sent through U.S. Mail), the Astronomical League's REFLECTOR
    magazine, and may additionally purchase discount subscriptions to
    SKY & TELESCOPE, ASTRONOMY, DEEP SKY, and TELESCOPE MAKING magazines.

        For information on membership, contact the Society at:

         Astronomical Society of the Atlantic (ASA)
         c/o Center for High Angular Resolution Astronomy (CHARA)
         Georgia State University (GSU)
         Atlanta, Georgia  30303  U.S.A.

         [e-mail] or [e-mail]

         ASA BBS: [phone], 300/1200 Baud.

        or telephone the Society recording at [phone] to leave
    your address and/or receive the latest Society news.

        ASA Officers and Council -

         President - Don Barry
         Vice President - Bill Bagnuolo
         Secretary - Ken Poshedly
         Treasurer - Alan Fleming
         Board of Advisors - Bill Hartkopf, Edward Albin, Jim Bitsko
         Council:  Larry Klaes, Michael Wiggs, Max Mirot, Eric Greene,
                   Patti Provost, Paul Pirillo, Becky Long, Jim Bitsko,
                   Julian Crusselle, Toni Douglas

        ARTICLE SUBMISSIONS -

        Article submissions on astronomy and space exploration to
    the EJASA 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:

        [e-mail], or ...!decwrl!wrksys.dec.com!klaes,
    or [e-mail], or [e-mail],
    or [e-mail]

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

        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.

        DISCLAIMER -

        Submissions are welcome for consideration.  Articles submitted,
    unless otherwise stated, become the property of the Astronomical
    Society of the Atlantic.  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).  This Journal is
    Copyright (c) 1990 by the Astronomical Society of the Atlantic.


                          AMATEUR ASTRONOMY IN SPAIN

                            by Jordi Iparraguirre

        For centuries Spain was not a major participant in the expanding
    fields of astronomy and astrophysics so prominent among some of its
    European neighbors.  This situation began to change in the early 1970s
    when several European nations decided to build their best astronomical
    observatories in the Canary Islands off the coast of Morocco.  This
    enterprise dramatically increased the number of Spanish astronomy
    students and research projects in the science, as Spanish astronomers
    receive a large portion of the scheduled observing time.  As with so
    many other nations, the introduction of professional astronomy in
    Spain eventually led to the growth of many amateur organizations.

        The man considered most responsible for bringing amateur
    astronomy to fruition in Spain was Josep Comas i Sola (1868-1937).
    Comas i Sola was a Catalan astronomer and the director of the
    Observatori Fabra in Barcelona.  He discovered eleven planetoids
    [1] and a periodic comet subsequently named after him. [2]  This
    astronomer is said to have been the first to detect a "diffuse edge"
    around Titan, the largest moon of the planet Saturn. [3]  This "edge"
    was caused by Titan's thick atmosphere, which was not officially
    confirmed until 1944 by the American astronomer Gerard P. Kuiper
    (1905-1973). [4]  Comas i Sola is regarded by many Spanish amateurs
    as the foremost astronomy popularizer of their country.

        Josep Comas i Sola founded one of the first amateur astronomical
    associations in Spain in 1911 called SADEYA (Sociedad Astronomica de
    Espana y America - the Astronomical Society of Spain and [South]
    America). [5]  At present the primary activity of this group is to
    produce a monthly star chart and ephemeras published in LA VANGUARDIA
    (The Vanguard), one of the most important newspapers in Spain.

        In 1948, members from SADEYA founded ASTER (Agrupacio Astronomica
    de Barcelona - the Astronomical Society of Barcelona; ASTER is the
    Greek word for "star").  ASTER has become one of the most active
    astronomy associations in Spain.  They were one of the first non-
    professional teams to pick up the radio transmissions of the Soviet
    satellite SPUTNIK 1 as it orbited Earth in 1957.  ASTER members also
    had the good fortune to be visited by the famous German rocket pioneer
    Hermann Oberth (1894-1989) and the Soviet scientist Leonid Sedov
    (Chief engineer on the SPUTNIK project) in October of 1957 at the
    International Astronomical Union (IAU) meeting held in Barcelona.

        Today, ASTER follows the solar observing program lead by SONNE,
    a West German association dedicated to observing the Sun (Sonne is
    the German word for Sun).  We send our observations of variable stars
    to AFOEV (Associacion Francoise d'Observateurs d'Estels Variables -
    the French Association of Variable Star Observers) and AAVSO (American
    Association of Variable Star Observers).  In the summer of 1989, ASTER
    members observed the major fading of the giant gas planet Jupiter's
    South Equatorial Belt [6].  Some of the main activities in ASTER are
    solar and planetary monitoring (Association of Lunar and Planetary
    Observers, ALPO), astrophotography (reprophotography and hypersensi-
    tized films), occultations, variable stars, and divulgation (popular-
    izing astronomy, teaching courses, and collaborating with the news
    media on events in the field).

        In 1960, a number of ASTER members founded Agrupacio Astronomica
    de Sabadell (Sabadell is a town near Barcelona).  A. A. Sabadell has
    several delegations across Spain.  Its prominent member is Josep
    Costas, who is known for his experience at observing the Sun (he has
    been studying Earth's star for fifty years) and telescope-making
    (Costas has made more than two thousand mirrors).  A. A. Sabadell's
    main activities are divulgation, occultations (European Asteroidal
    Occultations Network, EAON) [7], and solar observation.

        GEA (Grup d'Estudis Astronomics, the Astronomical Studies Group)
    was created in 1983 when a group of people from ASTER and A. A.
    Sabadell decided to work at more professional levels.  GEA is mainly
    composed of professional astronomers, astronomy undergraduate students
    and graduates, and highly skilled amateurs.  GEA's director is Josep
    M. Gomez, who recently discovered that SAO 139174 is both an eclipsing
    binary star and one of the one hundred brightest known variable stars.
    GEA leads the Spanish wing of IAPPP (International Amateur Professional
    Photoelectric Photometry).  GEA collaborates with IAPPP, EAON, and ALPO.
    Its principal observing site is in the Pyrenees Mountains.  Each summer,
    ASTER and several other groups are given the opportunity to use the
    GEA's fifty-centimeter (twenty-inch) telescope, as well as their two
    forty-centimeter (sixteen-inch) and four twenty-centimeter (eight-inch)
    Celestron and Meade.  These opportunities greatly help to improve the
    skills and knowledge of the groups.

        Gomez is considered by many to be the most important amateur-
    professional astronomer in Spain today.  His main interests of
    study are the atmosphere of Jupiter, photometric photometry, and
    solar phenomena.  GEA projects involve CCD (Charge-Coupled Device)
    imaging and software analysis in order to get high-resolution
    planetary images.

        Red Mira is a network of different associations that follow the
    same observing program on variable stars.  Their observations are
    sent to AAVSO and AFOEV.  There are a number of other astronomical
    groups in Spain, some of which you will find in the list near the end
    of this article.  The oldest and most active associations are located
    in Catalonia.

        In 1976, ASTER organized the first national amateur meeting
    in Barcelona.  Since then, these meetings have been organized by
    other associations in different cities every two years.  In 1987,
    the meeting returned to Barcelona (organized by SADEYA) and was
    focused on honoring Josep Comas i Sola on the fiftieth anniversary
    of his death.  The latest meeting, held in Madrid, joined amateurs
    and professionals from more than seventy astronomy groups all over
    Spain.

        There are two monthly astronomy magazines published in Spain:
    TRIBUNA DE ASTRONOMIA and ASTRONOMIA, ASTROFOTOGRAFIA Y ASTRONAUTICA.
    They often publish photographs and articles written by skilled
    amateurs.

        Since July of 1989, ASTER has begun to lead the e-mail commu-
    nications field in Spain.  We recently got in touch with a team of
    young businessmen interested in this area, thinking that e-mail could
    be a useful tool for the group.  Their system is called NEXUS.  It has
    the same software as BIX.  Though having been in operation for only
    one year now, NEXUS has given us the opportunity to moderate a forum
    of astronomical topics and have our own e-mail address.  This public
    forum allows us to talk about astronomy to a wide variety of people
    in many different fields.  ASTER has another private forum for
    associations and their members with which we share ephemeras data,
    answer questions about astronomy, present observing programs, and
    collect data.  ASTER also posts alerts regarding such events as
    comet hunts and variable star reports.

        Our plan is to eventually join together as many Spanish amateur
    astronomy associations as possible and try to connect to other asso-
    ciations from around the globe.  In fact, last summer ASTER wrote a
    letter to several other European amateur associations explaining our
    situation and future planning.  Don Miles, editor for the Electronic
    Circular of the British Astronomical Association (BAA), answered us.
    He is connected to Microlink Gold.  We have heard that some Italian
    amateurs are connected via FIDO.  At present, people from SADEYA, GEA,
    and ASTER are looking to have our own e-mail node, as there are some
    problems with sending e-mail through NEXUS (We receive mail, but we
    cannot send it).  We would also like to try packet radio.

        If you are interested in communicating with any Spanish amateur
    associations, the following is a list of some of the major groups
    with their regular mail and network address:

        SADEYA, Sociedad Astronomica de Espana y America
        Av. Diagonal, 377 2on
        08008 Barcelona
         [e-mail]

        ASTER, Agrupacio Astronomica de Barcelona
        Passeig de Gracia, 71 atic
        08008 Barcelona
         [e-mail]

        Agrupacio Astronomica de Sabadell
        C/Font, 1 1er.
        08201 Sabadell (Barcelona)

        GEA (Grup d'Estudis Astronomics)
        Ap. Correus 9481
        08080 Barcelona
         [e-mail] (To be implemented soon)

        Sociedad Malaguena de Astronomia
        Ap. Correos 6072
        29080 Malaga
         [e-mail]

        Associacio Valenciana d'Astronomia
        Apt. Correos 2069
        46080 Valencia
         [e-mail]
         (Juan Fabregat was AVA President)

        Agrupacion Astronomica de Madrid
        Ap. Correos 1039
        28080 Madrid

        Aranzadi Zientzi Elkartea
        Plaza Ignacio Zuloaga (Museo)
        20003 Donosti (San Sebastian)

        Agrupacion Astronomica Palmera
        Ap. Correos 449
        38780 S.C. de la Palma

        Agrupacion Astronomica de Tenerife
        Ap. Correos 10644
        38080 S.C. de Tenerife

        I would like to thank EJASA Editor Larry Klaes for "translating"
    my original article into readable English and for his general advice.

        Footnotes:

        1 - Comas i Sola discovered planetoids 925, 945, and 956.  He
            also rediscovered planetoids 629, 1102, 1117, 1136, 1188,
            1927AA (Sadeya), 1929WG, and 1929XA.

        2 - Periodic comet Comas Sola (1926f) was discovered on November
            4, 1926.  The comet has an orbital period of 8.54 years.

        3 - This discovery was made in 1920 and reported in ASTRONOMISCHE
            NACHRICHTEN, Number 4290.

        4 - See the April, 1982 article "Titan" in SCIENTIFIC AMERICAN by
            Tobias Owen.

        5 - The Sociedad Flammarion association was founded in 1881 in
            Jaen, but dissolved soon after.  ASTER has a telescope that
            is reputed to have been donated by a Sociedad Flammarion
            member which once belonged to the French astronomer Nicolas
            Camille Flammarion (1842-1925).  Like Josep Comas i Sola,
            Flammarion was an astronomy popularizer.

        6 - IAU Circular 4815, July 19, 1989.

        7 - The European Asteroidal Occultations Network (EAON) can be
            contacted through Mr. Roland Boninsegna, Rue de Mariembourg,
            35 B 6381 Dourbes, Belgium.

        About the Author -

        Jordi Iparraguirre is a computer science student at "Universitat
    Autonoma de Barcelona" in Catalonia.  Jordi has been the librarian of
    ASTER (Agrupacio Astronomica de Barcelona) since 1986.  As an amateur
    astronomer, Jordi is encouraging e-mail communication among Spanish
    amateurs and moderates the public astronomy forum on NEXUS.  He takes
    part in summer meetings organized by J. M. Gomez (GEA, IAPPP Spanish
    wing).  Jordi's professional interests include space probes and
    unmanned intelligent rovers as a means of exploring our solar system.
    He would very much like to take doctorate courses on these new
    planetary machines.

        If you would like to contact Jordi:

          E-mail:  [e-mail]        (Always, I hope!)
                   [e-mail]  (Expires in September of 1990)
          Regular mail:  See the ASTER address above.


                          THE COSMIC DISTANCE SCALE

                               by Eric Greene

        The history of astronomy is the history of humanity's discovery
    of the scale of the Universe.  The astronomers of ancient Greece made
    the first scientific attempts at determining the size of our planet
    Earth and the Universe within which we exist.  It was far easier for
    the Greeks to measure Earth accurately than the entire Universe.  This
    is not surprising:  Over two thousand years later we are still coming
    to grips with understanding a cosmos that is far vaster than the human
    mind can even begin to comprehend.

        Before discussing the cosmic distance scale as we understand
    it today, it is very important to comprehend the idea of parallax.
    Parallax is essentially the direct trigonometric measurement of
    distance which can easily be demonstrated:  Hold your index finger
    up against a distant background and look at it while alternately
    opening and closing each eye.  Your finger will appear to move
    against the background due to binocular vision, the different angle
    of vision for each eye.  If you measure the distance between your
    eyes and the amount of movement of your finger, it is quite simple
    to calculate the distance to your finger.

        Obviously the accuracy of this method is determined by the
    baseline of the measurements.  Human eyes are a few centimeters apart.
    This method will work out to a distance of twenty-seven meters
    (thirty yards) or so:  You can experiment with this by using objects
    farther away than your finger and distant backgrounds.  Objects more
    distant will cause too small a "parallactic displacement" to be
    discernible with the unaided eye.  Extending the observational
    baseline by separating the eyes is a difficult and painful propo-
    sition at best.  The same effect can be had by using two observers
    making the same measurement on the same object at the same time.
    This method was used by early astronomers to calculate a fair
    approximation of the distance from Earth to the Moon, but the
    unaided eye measurements were not accurate enough to measure
    anything more distant in space.

        Early telescopes were very primitive affairs with generally
    unstable mounts and inaccurate micrometers used for quantitative
    measurements.  The problem of knowing the distance to the stars
    remained unsolved for over two hundred years after the telescope
    was put into astronomical use.

        Since the accuracy of the parallax method depends upon the length
    of the baseline, the question of the longest baseline available became
    very important.  It is possible to view a star just after the Sun
    "sets" and, depending on the time of year, see it again just before
    Sun "rise".  Earth has rotated 180 degrees during this time, placing
    the observer on the other side of Earth (in reference to an outside
    observer, since the original observer is in the same geographic
    location).  The observer is working with a baseline equal to the
    diameter of Earth - about 12,800 kilometers (eight thousand miles).
    Even this baseline is not long enough to detect any parallax in
    the stars.

        The same observer can make observations of the same star six
    months apart.  During these six months, Earth has moved from one
    side of its orbit around the Sun to the other.  Since Earth circles
    the Sun at a distance of approximately 150 million kilometers (93
    million miles), the diameter of the orbit is 298 million kilometers
    (186 million miles).  Making observations every six months means
    working with a baseline of 298 million kilometers (186 million miles).

        With this technique, the German astronomer Friedrich Wilhelm
    Bessel (1784-1846) was able to detect the first stellar parallax in
    1838.  Bessel's subject was the orange (spectral type K) star 61 Cygni
    in the constellation of Cygnus the Swan.  The star was seen to move
    slightly against the background of dimmer and more distant stars,
    thus the measurement of this motion could easily be converted into
    kilometers.  The distance from Earth to 61 Cygni was calculated by
    Bessel to be over 96 trillion kilometers (sixty trillion miles), or
    about ten light years (the distance has since been refined to 11.2
    light years).  Attempts at measuring the distances to other stars
    proved unsuccessful, indicating that these suns must reside at far
    greater distances than 61 Cygni.  The Universe was becoming a much
    larger place than ever dreamed of before.

        One of the unusual properties of the Universe (from the average
    human standpoint) is that we never see the Universe as it is, but
    only as it was.  Light travels at approximately 300,000 kilometers
    each second (186,000 miles each second).  Incredibly swift though
    this velocity is, it still takes light a measurable period of time
    to cross astronomical distances.  Light requires about eight minutes
    to cross the 150 million kilometers (93 million miles) between the
    Sun and Earth, making our star about eight light minutes from our
    planet.  Consequently, we do not see the Sun as it appears in the
    present, but only eight minutes in the past.  Similarly, the light
    leaving the Sun at present will not arrive at Earth for yet another
    eight minutes.  This relationship between time and distance is one
    of the most fundamental concepts in astronomy.  It is impressed upon
    us with one of the most basic and essential units of astronomical
    measurement:  The light year.  One light year is the distance
    traveled by light in the course of one Earth year - roughly ten
    trillion kilometers (six trillion miles).

        It became much more convenient to talk of the distance to 61
    Cygni as 11.2 light years, rather than using trillions of kilometers.
    Yet this star is one of the closest to Earth; when speaking of the
    distances to other galaxies, we need to talk of hundreds of millions
    of trillions of kilometers.  Using light years makes things simpler.

        Another unit of distance finding increased favor in astronomy
    is the parsec (pc).  This measure is defined by parallax.  If an
    object is at a distance of one parsec (3.26 light years), then it
    will exhibit a parallactic displacement of one arcsecond over a
    three-month period.  At even greater distances, measurement is
    often quoted in megaparsecs.  One megaparsec equals 3.26 million
    light years and reflects the average distance between galaxies.
    The most distant galaxies from us are thousands of megaparsecs
    away.  The Universe has become ever larger.

        Next comes the problems of determining distance once moved far
    out enough that direct measurement of parallax becomes impossible.
    We will discover that distance scales become quite vague beyond this
    distance.  One of the astronomer's favorite pastimes is changing the
    distances to the galaxies.  The implications to this are interesting,
    since time and distance are so closely linked.  If an astronomer
    places the most distant galaxies at ten billion light years and if
    the galaxies were formed shortly after the creation of the Universe,
    then the Universe is somewhat older than ten billion years.  If the
    most distant galaxies are placed at twenty billion light years, the
    age of the Universe must also double to allow sufficient time for
    the light from those objects to reach us.  The distance scale has a
    profound effect on our concepts concerning the age and formation of
    the Universe.

        With continually refined techniques and improved telescopes, it
    is possible to measure parallax out to distances of over one hundred
    light years with fair reliability.  Once we reach a distance of three
    hundred light years, the margin for error exceeds the measurement and
    parallax ceases to be a useful means of determining distance.  While
    three hundred light years is roughly three quadrillion kilometers
    (1.8 quadrillion miles), this is still right on our doorstep as far
    as celestial distances go.  Astronomers desired the means to determine
    the distances to the far reaches of our Milky Way Galaxy and the rest
    of the Universe.  A new method of measurement was needed, but no one
    appeared to have an idea on how to approach the problem.

        To the casual observer in ancient times, the night time sky was
    a perfect, changeless place.  The eternal stars seemed never to alter
    position or brightness.  The planets, comets, and other phenomena
    that seemed to change the appearance of the sky were not considered
    to be parts of the celestial sphere; the stars themselves were
    unchanging for all times.

        Arabian astronomers during the European Middle Ages were astute
    observers of the sky.  They noticed that several stars seemed to
    change brightness.  They recorded their amazement at this fact by the
    names given to these stars:  Algol, in the constellation of Perseus,
    translates to the Demon and is the basis for our word "ghoul".  Mira,
    in the constellation of Cetus the Whale, translates as "wonderful".
    These stars changed brightness over periods of time - a matter of days
    for Algol and months for Mira - and these stars became the first of a
    large group of stars known as variables.  Later research showed that
    some variables, such as Algol, were binary stars in which the dimmer
    companion occasionally blocks the light of the brighter star from our
    viewpoint on Earth.  Others, such as Mira, varied because of actual
    changes in the intrinsic brightness of the star itself.  The first
    type of star is known as an eclipsing binary, while the second type
    is broken into many different categories, such as recurrent nova,
    dwarf nova, Cepheid variable, RR Lyra, and so forth.  We shall
    concentrate on the Cepheid variables.

        Variable stars are characterized by their light curve.  This
    curve is a simple graph of the star's brightness on a time scale
    showing the period of brightness change of the star.  Cepheid
    variables have a characteristic light curve with a fast rise to
    maximum brightness, followed by a slow decline to minimum magnitude.

        In 1912, the American astronomer Henrietta Leavitt was studying
    Cepheid variables in the Small Magellanic Cloud (a companion galaxy
    to the Milky Way visible from the Southern Hemisphere).  Astronomers
    generally prefer to observe objects in clusters and nearby galaxies,
    since they can consider all the objects they view as being at the same
    distance - just as someone in New York City would consider all the
    people living in London to be the same distance away.  Any brightness
    differences are assumed to be real intrinsic differences, rather than
    differences caused by distance alone.  Leavitt noticed a correlation
    between the brightness of a Cepheid variable and its period.  Her
    observations were later formulated into the famous Cepheid Period-
    Luminosity Law by Harlow Shapley in 1917.

        The law states there is a direct relationship between the period
    of a Cepheid and its absolute (internal) brightness.  Since Cepheid
    variables are fairly common stars, there are several within the three
    hundred light year range of direct distance measurement.  It therefore
    became possible to work out their absolute magnitudes.  Once these
    were determined, the Cepheids became a tape measure for finding vast
    distances quite easily.  Measure the light curve of the variable and
    a simple table tells what its absolute magnitude is.  Once you know
    how bright it actually is, the difference between perceived brightness
    (dimmed by distance) and actual brightness tells the distance.

        Since Cepheids are among the more luminous stars, this ruler
    became useful for measuring the distances of the galaxies that can
    be resolved into individual stars in large telescopes.  In the 1940s,
    Walter Baade was able to make out Cepheids in the Andromeda Galaxy
    and determined that this galaxy was at a distance of 2.1 million
    light years - our next door neighbor, as far as galaxies go.  New
    telescopes and observing techniques allow observing Cepheids out to
    distances past twenty million light years.  Beyond this distance,
    even the greatest telescopes are unable to resolve individual stars,
    requiring other techniques for intergalactic distance measurement.
    These techniques, reaching beyond the nearby galaxies out to the
    edges of the Universe, will form a later article.

        Recommended reading:

        Dickinson, Terence, THE UNIVERSE...AND BEYOND, Camden House
          Publishing, Ltd., Camden East, Ontario, Canada, 1986

        Ferris, Timothy, COMING OF AGE IN THE MILKY WAY, William
          Morrow and Co., Inc., New York, 1988

        Hartmann, William K., and Ron Miller, CYCLES OF FIRE,
          Workman Publishing, New York, 1987

        McAleer, Neil, THE MIND-BOGGLING UNIVERSE, Doubleday & Co.,
          Inc., Garden City, New York, 1987

        Moore, Patrick, ASTRONOMERS' STARS, W. W. Norton & Company,
          New York, 1989

        Whitney, Charles A., THE DISCOVERY OF OUR GALAXY, Alfred A.
          Knopf, Inc., New York, 1971

        About the Author -

        Eric Greene, ASA Observing Coordinator, is an active and avid
    amateur with a talent for astronomical education and an interest in
    presenting astronomy comprehensively to all levels of interest in
    the field.


                        MILTON UPDEGRAFF, ASTRONOMER

            by Darwin Christy, Buffalo Astronomical Association

        Milton Updegraff, a little-known American astronomer, was born
    on February 20, 1861, in Decorah, Iowa.  After graduating from the
    University of Wisconsin in 1884, Updegraff was employed as an aid
    on the United States Coast and Geodetic Survey until 1887.  He became
    an Astronomo Segundo (assistant) Observatorio Nacional in Cordoba,
    Argentina, from 1887 to 1890.

        Updegraff taught astronomy at the University of Missouri from 1890
    to 1899, after which he was selected for the position of Professor of
    Mathematics for the United States Navy (USN).  Updegraff subsequently
    became an astronomer in the U.S. Naval Observatory until 1902.  While
    there, he was placed in charge of the U.S. Naval Observatory's May
    1900 Eclipse Party at Barnesville and Griffin in Georgia.  In 1902,
    Updegraff accepted the appointment as Instructor in the U.S. Naval
    Academy, which he held until 1907.

        Being an experienced astronomer, Updegraff was designated as
    director of the Nautical Almanac in Washington from 1907 to 1910.
    During the last two years of his time as director, Updegraff was
    also assigned to the fifteen-centimeter (six-inch) transit circle
    of the Naval Academy.  A transit circle is a special telescope that
    only moves north-south, fixed in hour-angle (that is, it sweeps the
    meridian).  When a star passes through its crosshairs, a timing
    measure can measure the star's right ascension very accurately.
    Also, by examining stars of known right ascension, the local time
    can be ascertained very accurately.  This method was used to keep
    inaccurate clocks properly set until atomic clocks were developed.
    Now it is used to measure Earth's variation in its rate of rotation.

        From 1913 to 1915, Updegraff headed the geodetic and other
    scientific work in the American Survey of Samoa.  From 1915 to 1917,
    he was stationed at the Mare Island Navy Yard, at the north end of
    San Francisco Bay, California, and was also a meteorological observer
    in Arizona, retiring in July of 1920 with the rank of Commander.  He
    was elector of the New York University Hall of Fame in 1925, 1930,
    and 1935, and also served as a Fellow of the American Association
    for the Advancement of Science (AAAS).

        It is difficult to find biographical material on Updegraff, as his
    contributions to astronomy were relatively minimal.  Updegraff did,
    however, hold a number of significant positions as an astronomer and
    teacher of astronomy and mathematics, and wrote several articles on
    professional subjects.  Living at his home in Prescott, Arizona in his
    later years, Updegraff passed away on September 12, 1938, at the age
    of seventy-seven years.

        From the Editor:  No known history has been written describing
    the May 1900 Eclipse Party conducted in Georgia by the United States
    Naval Observatory and Milton Updegraff.  A worthwhile research pro-
    ject for any interested readers would be to request records from the
    Naval Observatory pertaining to Professor Updegraff and the Georgia
    Expedition, in order to prepare a report on this virtually unknown
    and important event in Georgia's past.  In 1900, the science and
    engineering of photography, solar physics, and portable observing
    instrumentation were in rapid development.  An account of the eclipse,
    therefore, would encapsulate the state of a large part of astronomy
    at that time.  If interested, please contact the Astronomical Society
    of the Atlantic at one of the addresses listed in the ASA Membership
    section of this issue.  We can then direct you to some information
    sources at the Naval Observatory as a starting point.

        About the Author -

        Darwin Christy is Newsletter Editor of the "Spectrum, the newsletter
    of the Buffalo Astronomical Association in Buffalo, New York and an
    active amateur astronomer with an interest in the history of astronomy.


     THE ELECTRONIC JOURNAL OF THE ASTRONOMICAL SOCIETY OF THE ATLANTIC

                         April 1990 - Vol. 1, No. 9

                          Copyright (c) 1990 - ASA


--
Donald J. Barry       [phone]         | [e-mail]
Center for High Angular Resolution Astronomy | President, Astronomical
Georgia State University, Atlanta, GA 30303  | Society of the Atlantic

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End of SPACE Digest V11 #216
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