Photometry of Asteroids

I   have   always   been   attracted   to   the   possibility   of   doing   worthwhile   science   whilst   engaging   in   my   hobby.   In 2001   and   2002,   I   discovered   three   previously   unknown   asteroids   which   have   since   been   numbered,   124033 (2001   FP127),   112835   (2002   QL17),   and   191213   (2002   RA01).   At   a   workshop   in   Australia   in   2003   which brought   together   amateur   and   professional   astronomers,   it   was   pointed   out   that   while   discovering   a   new object   in   space   is   always   exciting,   amateurs   could   contribute   more   worthwhile   science   if   they   engaged   in photometry   of   asteroids.   In   astronomy,   photometry   is   the   measurement   of   light   emitted   by,   or   reflected   by, a celestial object. Stars emit light of their own; asteroids reflect light from the Sun. Between   the   orbit   of   Mars   and   the   orbit   of   Jupiter   there   is   a   huge   gap.   Many   believed   that   a   planet remained   to   be   found   somewhere   in   that   gap.   On   the   1st   of   January,   1801,   a   Catholic   priest,   astronomer and   mathematician   by   the   name   of   Guiseppe   Piazzi,   discovered   a   celestial   body   in   this   gap.   He   called   it “Ceres”   after   the   Roman   goddess   of   grain.   Following   Piazzi’s   discovery,   other   bodies   were   discovered   in   this space between Mars and Jupiter, though Ceres would remain the largest.   The     illustration     on     the     left     comes     from N.A.S.A.      It   shows   the   wide   range   of   sizes   of   a number   of   asteroids   in   the   space   between Mars   and   Jupiter.   This   space   is   now   known   as the “Main Belt” of asteroids. Ceres       went       through       a       number       of classifications.      At      first      described      as      a “planet”,    it    would    be    categorised    as    the largest   “minor   planet”,   and   nowadays,   as   a “dwarf     planet”.     Throughout     all     these     re- classifications,   the   term   “asteroid”,   meaning “star-like”,    has    served    as    a    collective    term that includes them all. Because   of   its   relatively   large   size,   Ceres’   own   gravity   has moulded    it    into    a    spherical    shape.    The    next    largest asteroid,   Vesta,   is   also   slightly   spherical;   but   after   that   the bodies   orbiting   in   this   Main   Belt   are   typically   irregular   in shape.     The     irregular     shape     of     these     bodies     actually provides    us    with    a    helpful    quality    to    research    them further.   Many   of   these   bodies   are   tumbling   as   a   result   of collisions   between   themselves.   As   they   tumble,   they   may present   themselves   to   us   on   Earth   first   broadside,   then end   on.   The   sunlight   they   reflect   thus   rises   and   falls   twice with    each    rotation.    The    speed    of    rotation    gives    a    hint about   their   composition,   as   fast   rotators   must   be   made   of iron   in   order   to   withstand   the   centrifugal   force   of   their rotation.      Information      about      composition      may      be important    if    we    ever    have    to    deflect    an    asteroid    on    a collision course with the Earth. Of   course,   through   any   telescope on   Earth,   asteroids   do   not   appear as    in    the    animated    illustration above.     They     appear     only     as points      of      light      which      move against   the   background   of   stars. The   stars   are   much   further   away, and     like     the     horizon     from     a moving      train,      appear      to      be motionless.   Asteroids   are   part   of our   Solar   System   and   thus   much closer.    Their    motion    is    readily apparent    when    photos,    say    15 minutes     apart,     are     combined. The     animated     photo     adjacent from       NASA       is       created       by combining          several          frames separated by time. Although   the   asteroid   cannot   be   seen   rotating   in   such   photos,   measurement   of   the   light   reflected   by   the asteroid   rises   and   falls   in   a   “lightcurve”   that   can   be   represented   on   a   graph.   If   the   asteroid   is   a   fast   rotator, a   full   lightcurve   can   be   established   in   a   relatively   short   period   of   time.   However,   if   the   asteroid   is   a   slow rotator,   the   length   in   time   of   the   full   curve   may   exceed   the   hours   of   darkness   available   to   the   astronomer. This   gives   rise   to   collaborations   between   astronomers   scattered   around   the   world   in   a   kind   of   relay.   My first   collaboration   took   place   in   July,   2005,   in   response   to   a   request   for   photometry   of   the   asteroid   1992 UY4   by   Dr   Lance   Benner   of   NASA/JPL.   Dr   Benner   was   leading   a   group   of   radio   astronomers   who   were turning   their   attention   to   the   asteroid.   Some   radio   telescopes,   which   normally   only   receive   data,   are   also used   to   transmit   radar   wavelengths.   The   radar   signals   are   bounced   off   objects   like   asteroids   to   gather   more information   on   the   target.   However,   astronomers   using   radar   sometimes   need   information   on   rotation rates    derived    from    optical    observations    in    order    to    set    parameters    for    their    radar    signals.    Those collaborating   in   support   of   Dr   Benner’s   request   included   observers   in   the   U.S.A.,   Brazil,   Spain,   Switzerland, and myself in Australia. Our combined data was used to develop a lightcurve seen below. As   reported   in   the   Minor   Planet   Bulletin   (Vol.   33/1),   “In   early   August,   Dr.   Benner   reported   his   group   had successfully   observed   1992   UY4   and   that   the   efforts   of   this   collaboration   had   proven   invaluable   in   making that possible.” I   will   post   any   future   asteroid   photometry   on   this   website   after   it   has   been   published   in   the   Minor   Planet Bulletin .   I   am   not   sure   I   want   to   go   to   the   trouble   of   posting   past   photometry   of   asteroids   on   this   website   as it does not seem like a good use of time.

Photometry of Variable Stars - Introduction

There    are    many    varieties    of    variable    stars.    In    fact,    a    listing    of    the    various    types    is    mind-boggling. Consequently,   this   introduction   will   focus   on   only   one   type   which   I   intend   to   pursue,   namely,   eclipsing binary pairs. These   pairs   consist   of   two   stars   orbiting   around   their   common   centre   of   gravity.   Usually   one   star   is   smaller in   dimensions   than   the   other;   but   the   smaller   star   is   nevertheless   denser,   and   thus   more   massive   than   the larger star. To understand that notion, consider and compare a cannon ball with a balloon. Such   is   the   distance   of   all   stars   from   the   Earth,   (with   the   exception   of   the   Sun),   that   they   only   appear   as pinpoints   of   light.   They   cannot   be   resolved   by   the   optics   of   our   telescopes   into   discs.   The   disc   shape   of stars   in   our   photographs   arises   from   the   pinpoint   of   light   wandering   about   on   the   imaging   chip   due   to atmospheric   fluctuations   and   tiny   mechanical   imperfections   in   the   telescope   mount   over   the   course   of   a time   exposure.   Consequently,   a   pair   of   eclipsing   binary   stars   appears   as   one   single   pinpoint   of   light.   How then   do   we   know   that   this   single   pinpoint   of   light   is   actually   a   binary   pair?   The   answer   is   some   detective work!   A   light-curve   is   a   graph   of   the   amount   of   light   coming   from   a   celestial   object,   and   when   the   orbital plane   of   the   binary   pair   is   so   aligned   with   respect   to   the   Earth   that   the   stars   take   it   in   turn   to   eclipse   each other,   the   light-curve   shows   the   tell-tale   signs.   The   animated   graphic   which   follows   makes   this   easier   to understand. A graph below the stars shows how the orbital motion translates into a light-curve. When   a   sequence   of   photographs   of   an   eclipsing   binary   pair   is   taken   over   a   period   of   some   hours,   it usually   reveals   the   telltale   shape   of   an   eclipsing   binary   light-curve.   As   the   binary   pair   continue   to   orbit around   their   common   centre   of   gravity,   the   light-curve   is   repeated   over   and   over.   Such   repeated   light- curves   can   be   overlaid   each   other   to   get   a   more   accurate   measurement   of   their   cycle.   Let’s   jump   ahead, with   a   light-curve   from   a   later   page   in   the   website,   of   the   eclipsing   binary   stars   V0676   Cen.   You   will   notice the   characteristic   “M”   shape   of   the   curve,   and   the   fact   that   the   minimum   point   in   the   middle   does   not   dive down   as   far   as   the   minimum   points   on   either   side.   This   fact   points   to   the   unequal   spatial   dimensions   of the two stars. Bear   in   mind   that   through   this   process   we   have   concluded   that   just   a   single   point   of   light   in   the   night   sky is   actually   a   pair   of   stars   orbiting   around   their   common   centre   of   gravity;   and   that   the   stars   are   of   unequal size and mass. But wait! There’s more! The   gravitational   fields   around   these   two   stars   interact   in   a   very   interesting   way.   Very   close   to   the   surface of   each   star   the   gravitational   field   looks   very   much   like   any   single   star.   But   as   one   moves   away   from   the surface,   the   gravitational   fields   of   each   star   begin   to   interact.   The   result   is   illustrated   by   the   following graphic. The   gravitational   fields   around   the   binary   pair   are   known   as   Roche   lobes.   The   point   marked   L1   in   the diagram   is   known   as   the   primary   Lagrangian   point.   The   smaller   star   in   terms   of   dimensions   is   nevertheless the   star   with   the   greatest   mass.   It   is   possible   for   the   smaller   star   to   rip   off   gas   from   the   larger   star,   and when    this    happens    the    mass    usually    flows    through    the    primary    Lagrangian    point.    Of    course,    the illustration   above   is   two   dimensional.   In   reality,   the   gravitational   fields   are   three   dimensional   and   the gravtational fields are more in the shape of an hour glass.

V0676 Centaurus

All   of   the   variable   stars   being   targeted   by   the   group   I   belong   to   are   in   the   southern   hemisphere.   This   is because   most   professional   and   amateur   astronomers   are   located   in   the   northern   hemisphere   and   are unable   to   view   these   stars.   In   consequence,   southern   hemisphere   variable   stars   are   often   neglected.   This program aims to overcome that neglect. Lately   I   have   been   targeting   eclipsing   binary   stars   in   the   constellation   of   Centaurus.   This   page   in   the website   is   given   over   to   V0676   Centaurus,   which   is   usually   abbreviated   as   V0676   Cen.   Information   of interest   is   found   by   determining   the   shape   of   the   lightcurve,   and   from   the   ‘signature’   of   the   lightcurve, the   nature   of   the   binary   pair.   Is   one   star   larger   than   the   other?   How   far   apart   are   they   in   their   orbits?   Are their   orbits   as   regular   as   clockwork   giving   an   unchanging   period?   Is   there   any   exchange   of   mass   between one star and the other? Initially   the   period   of   the   lightcurve   may,   or   may   not,   be   known.   So   one   of   the   first   tasks   is   to   observe   the star   over   sufficient   time   to   determine   its   period   and   the   times   of   ‘minima’   where   the   eclipse   reaches   its extreme point. Here is a plot of the lightcurve of V0676 Cen over one night - this is a ‘raw’ curve: Note   that,   in   this   section   of   the   curve,   the   minima   are   unequal.   One   star   of   the   binary   pair   is   eclipsing the   other   more   completely,   so   that   the   light   travelling   to   us   is   dimming   more   on   this   occasion   than   when it is the other way around. Note    also    that    there    are    gaps    in    the    lightcurve    which    may    affect    the    accuracy    of    the    calculations. Sometimes   this   is   because   the   hours   of   darkness   available   to   the   astronomer   make   it   not   possible   to cover   the   entire   curve.   (Hours   of   darkness   available   to   the   astronomer   are   longer   in   winter   than   in summer.)   Another   cause,   and   the   one   with   the   major   impact   on   this   data,   is   that   technical   problems occur   which   bring   a   halt   to   data-gathering.   This   is   pretty   frustrating   for   the   astronomer,   but   there   are typical causes for these problems. Many    amateur    astronomers    mount    their telescopes    on    what    is    called    a    German Equatorial   mount.   Here   is   an   illustration   of that kind of mount: On    the    left    is    a    snapshot    of    a    German Equatorial   mount   which   has   been   tracking   a star   as   it   rises   in   the   east.   One   of   the   axes   of the   telescope   mount   is   aligned   so   that   it   is parallel   with   the   Earth’s   rotational   axis.   (This is   the   Right   Ascension    axis).   As   the   Earth   rolls on    its    axis    toward    the    east,    the    telescope mount    is    able    to    track    the    star    by    rolling towards    the    west.        However,    as    the    star approaches   the   meridian   straight   above,   the telescope   is   unable   to   track   it   any   further, because   the   ‘science’   end   of   the   telescope would     run     into     the     pier     supporting     the telescope   mount.   At   this   point,   the   telescope   must   do   a   ‘meridian   flip’,   which   involves   the   scope   rolling over to the east and then doing a 180 degree turn on its declination axis. The   result   of   this   flip   is   that   the   image   focused   onto   the   camera   chip   is   rotated   180   degrees   as   well.   This can   make   processing   of   the   night’s   sequential   images   of   the   target   difficult.   It   also   adds   complication   to the    task    of    tracking    the    star.    When    the    telescope    is    locked    onto    a    target,    the    motors    driving    the telescope   around   the   Right   Ascension   axis   have   their   speed   set   to   match   the   rotation   of   the   Earth. However,   the   slightest   imperfections   of   the   gearing   results   in   varying   rotational   speed.   To   overcome   this, a   second   imaging   chip   is   often   used   to   monitor   any   movement   of   the   star   focused   onto   the   chip.   As   soon as   movement   is   detected,   the   guide   chip   sends   corrections   to   a   prism   in   front   of   the   chip   so   that   tiny corrections   to   alignment   can   be   made.   If   the   movement   exceeds   a   certain   amount,   corrections   are   then sent to the motors. The   picture   on   the   right   shows   the   “field   of view    indicator”    for    an    astronomical    camera with   both   an   imaging   and   a   guide   chip.   The target   is   shown   as   a   star   circled   in   yellow   and the    larger    rectangle    represents    the    field    of view     of     the     imaging     chip.     The     smaller rectangle   represents   the   field   of   view   of   the guide   chip.   The   star   within   that   field   of   view   is the   guide   star.   The   guide   chip   locks   onto   a star   just   outside   of   the   area   of   interest,   but fairly    close.    The    circles    encompassing    the guide   chip   show   where   the   guide   chip   would be   if   the   camera   was   rotated.   The   180   degree rotation    caused    by    a    meridian    flip    would mean   that   there   is   no   guide   star   to   lock   onto! One   way   around   this   problem   is   to   place   a “rotator”   in   the   optical   train   and   rotate   the camera 180 degrees after a meridian flip. This   process   takes   time,   and   in   addition,   there   may   be   a   “dead   zone”   in   the   telescope’s   ability   to   point   at the   meridian   from   either   side.   It   may   also   be   necessary   to   refocus   around   this   time   as   the   telescope cools   and   changes   the   focal   length   inadvertently.   Software   can   assist   by   automatically   refocusing   the star,   but   some   focusing   software   is   more   equal   than   others.   All   these   delays   can   lead   to   a   gap   in   the   data and   thus   a   gap   in   the   plotted   lightcurve.   Don’t   go   into   this   hobby   if   you   don’t   have   good   tolerance   for frustration! One   answer   to   these   problems   is   to   go   back   night   after   night   and   get   more   lightcurves   of   the   same object.   Then,   instead   of   plotting   the   lightcurve   as   “raw”   data   separated   by   days   at   a   time,   see   if   you   can “phase”   the   data,   by   identifying   where   a   lightcurve   is   being   repeated   over   and   over.   This   is   what   has   been done in the following graph. It’s a bit messy in places, but remember, this is the real world. So there you have it. My work on this eclipsing binary pair to date.

V0677 Centaurus

It   seems   I   am   working   my   way   through   eclipsing   binaries   found   in   the   constellation   of   Centaurus.   This   is not   totally   by   accident.   The   Earth   not   only   rotates   on   its   axis,   it   is   also   moving   along   in   its   orbit   around the   Sun.   The   result   is   that   particular   stars   rise   earlier   and   earlier   each   night   so   that   some   are   already   high in   the   sky   by   the   time   that   darkness   falls   and   there   are   fewer   hours   of   darkness   left   before   they   set.   Since the   aim   is   to   get   as   much   of   the   lightcurve   as   possible,   it   is   necessary   to   move   along   to   new   targets   after a   few   weeks   or   months.   At   the   moment   I   am   trying   to   get   another   eclispsing   variable   in   the   constellation of   Centaurus   before   it   becomes   too   late.   V0676   Cen   is   followed   by   V0677   Cen   in   the   General   Catalogue   of Variable   Stars   (GCVS).   If   the   previous   target   pages   have   seemed   to   have   followed   a   simple,   logical   pattern, then it’s time to welcome chaos. The   measurement   of   a   star’s   magnitude   depends   on   a   simple   linear   relationship   between   the   amount   of light   that   falls   on   the   imaging   chip   and   the   camera’s   registration   of   intensity.   Put   simply,   in   a   linear relationship,   each   unit   of   light   falling   upon   the   imaging   chip   leads   to   a   proportional   increase   in   signal registered   by   the   chip.   However,   beyond   a   certain   range,   this   linear   relationship   can   fall   apart   and   the pixels   on   the   imaging   chip   are   said   to   be   “saturated”.   The   problem   with   initial   attempts   at   recording   a light   curve   is   that   one   does   not   know   how   the   brightness   of   the   star   at   its   peak   of   variability   will   affect the   camera.   The   longer   the   exposure,   the   more   likely   the   camera   will   go   beyond   linearity.   At   the   other extreme,   a   shorter   exposure   may   be   too   short   to   achieve   sufficient   signal-to-noise   ratio   (SNR)   and   one will   be   left   trying   to   measure   the   star’s   magnitude   when   the   impression   it   leaves   on   the   imaging   chip   is barely    above    the    random    fluctuations    of    signal    in    the    chip    itself    caused    by    heat    in    the    ambient temperature.   Thus   the   other   night   my   attempt   to   get   better   SNR   on   V0677   Cen   seemed   OK   at   first,   but later   into   the   night   V0677   started   to   saturate   my   camera.   Observations   of   variable   stars   are   usually   taken through   specific   filters   designed   for   scientific   use,   and   traditionally   these   have   been   the   Johnson-Cousins combination   known   as   B,   V,   R,   and   I.   I   have   as   a   matter   of   course   been   observing   through   both   the   B   and V    filters,    but    usually    graphing    only    the    V    results.    It    was    interesting    to    discover    that    while    my    V observations   had   moved   into   saturation,   my   B   filter   observations   had   not.   Here   is   a   graph   of   the   chaos that ensued: The   emerald   green   symbols   are   actually   a   graph   of   the   B   observations.   The   blue   cross   symbols   are   a graph   of   the   V   observations   on   the   same   night,   but   the   other   V   observations   are   found   at   the   top   of   the graph. Chaos? Not really. Just more work needs to be done.

God’s Two Books - Read First

In   popular   parlance,   religious   belief   and   science   are   portrayed   as   being   in   conflict,   with   the   superstition   of religion   attempting   to   stifle   the   dawning   of   a   newly   enlightened   science.   Since   so   much   of   modern   science arose in the West, the chief targets of this portrayal are the Christian churches. There   are   two   groups   which   have   an   interest   in   perpetuating   the   idea   that   the   Christian   Faith   and   science are   at   loggerheads.   The   first   are   the   “New   Atheists”   who   would   like   to   claim   science   as   their   own   and   thus portray   anything   but   atheism   as   being   ‘unscientific’.   The   second   are   fundamentalist   Christians   who   seek some    kind    of    security    for    their    faith    in    an    ‘infallible    Bible’.    This    retreat    often    takes    the    form    of misunderstanding   the   genre   of   the   many   different   types   of   literature   which   are   found   within   that   collection of books we call the Bible. Needless to say, this retreat plays right into the hands of the New Atheists. The   problem   for   both   these   groups   is   that   there   is   a   centuries-long   tradition   of   scientific   research   motivated by   the   theological   stance   of   the   Christian   Church,   especially   in   the   West.   This   centuries-long   tradition   has resulted   in   many   Christians,   and   especially   clergy,   being   involved   in   extending   the   horizons   of   science.   The reason   for   this   is   not   ,   as   some   clown   once   said,   because   clergy   only   work   on   Sundays   and   are   free   on   other days   of   the   week   to   pursue   their   own   interests.   (Nothing   could   be   further   from   the   truth!)   It   is   because   the Christian   churches   have   for   centuries   seen   Nature   as   a   means   through   which   God’s   nature   is   revealed. Hugh   of   St   Victor   put   it   most   succinctly:   If   God   is   the   Creator,   then   “Nature   is   a   book   written   by   the   finger   of God”.   To   the   notions   inherited   from   Judaism   that   “the   heavens   reveal   the   glory   of   God”,   Christians   added their   belief   that   Christ   bore   the   imprint   of   the   divine   in   and   through   whom   all   things   came   into   being.   This belief   easily   accommodates   the   emergence   of   the   universe   13.5   billion   years   ago.   Indeed,   the   Big   Bang theory   was   proposed   by   a   Jesuit   priest,   Fr   Georg   Lemaitre.   This   belief   also   easily   accommodates   a   process of   Evolution   for   the   development   of   biological   life   forms   on   planet   Earth.   Clearly,   such   an   approach   does not   regard   the   Creation   stories   in   Genesis   as   literal   accounts   of   how   the   world   came   into   being.      Rather   they are seen as stories which tell spiritual truths about purpose and accountability. The   iconic   hero   for   the   New   Atheists   is   Galileo   Galilei,   in   his   conflict   with   the   Roman   Catholic   Church   over heliocentrism.   Apart   from   the   fact   that   this   conflict   took   place   over   just   a   few   years   in   the   two   millenia   of the   Christian   churches   existence,   Galileo   himself   lets   them   down   by   being   an   avid   Christian   and   the   author of   Christian   theology.   Galileo’s   book   on   Natural   Theology   entitled,   A   Letter   to   the   Grand   Duchess   Christina,      sets   out   Galileo’s   views   on   revelation.   It   is   also   interesting   to   note   that   in   this   book   Galileo   attributes opposition to his heliocentric views, not to doctrinal views, but to personal vendettas. The   theology   of   “God’s   Two   Books”,   briefly   described   above,   can   be   illustrated   in   the   following   way.   The sources   of   revelation   underlying   Christian      Faith   are   understood   as   the   “Book   of   Scripture”,   that   is,   that collection   of   books   known   as   the   Christian   Bible;   and   the   “Book   of   Nature”,   which   nowadays   is   generally known as “science”.

Christian Faith

The   adherence   of   famous   scientists   in   the   history   of   science   to   this   framework   is   readily   illustrated.   The Lutheran   educational   system   established   by   Martin   Luther’s   right   hand   man,   Philip   Melanchthon,   had   a dual   purpose.   One   was   to   produce   Lutheran   pastors   for   congregations   and   the   other   was   to   produce teachers   for   their   schools.   When   Johannes   Kepler   entered   this   system   he   had   thought   to   become   a   church pastor.    However,    by    the    time    he    exited    the    system    he    had    shown    a    strong    passion    and    ability    in mathematics   and   astronomy.   The   faculty   noticed   this   and   transferred   him   to   the   other   stream,   sending him   out   as   a   science   and   mathematics   teacher.   Kepler   was   surprised   at   first,   but   the   faculty’s   wisdom   was vindicated   by   Keplers   subsequent   career.   At   the   time   of   his   exit   from   the   Lutheran   educational   system Kepler   demonstrated   his   understanding   of   the   rationale,   declaring   that   “astronomers   are   the   priests   of God interpreting the Book of Nature”. Galileo Galilei took a very similar position. In his book, Letter to the Grand Duchess Christina,  Galileo states: “For   the   Holy   Scripture   and   Nature   derive   equally   from   the   Godhead,   the   former   as   the   dictation   of the Holy Spirit and the latter as the most obedient executrix of God’s orders.” ⁽¹⁾ Galileo   also   outlines   in   this   letter   the   view   that,   in   the   Scriptures,   God   accommodates   the   message   to      “the very    unrefined    and    undisciplined    masses”,    so    that    they    would    understand    things    according    to    their existential   experiences,   and   not   have   demanded   of   them   an   understanding   beyond   their   ability,   as   in   the study of Nature. Over in the Protestant camp, Kepler held exactly the same view of “accommodation”. Footnotes:    1)    Maurice    A.    Finocchiaro.    The    Galileo    Affair.     A    Documentary    History.    1989.    University    of California Press. pp.92-93.

Science

Christian Bible

Science and Faith - an historical perspective

The    usual    narrative    of    astronomical    history    from    the    time    of    Copernicus,    Kepler    and    Galileo,    goes something   like   this:   Copernicus   brought   forward   the   theory   that   instead   of   the   Sun   revolving   around   the Earth,   the   Earth   and   the   other   planets   revolved   around   the   Sun.   Copernicus   was   so   afraid   of   persecution by   the   Roman   Catholic   Church      over   this   idea   that   he   postponed   publication   of   his   theory   until   he   was   on his   deathbed.   When   Galileo   Galilei   championed   Copernicus’   theory   he   was   persecuted   by   the   Roman Catholic   Church.   The   Protestant   leader,   Martin   Luther,   also   rejected   Copernicus’   theory.   All   of   this   goes to show how the steady march of science has been opposed by the superstition of the Christian Church. This   narrative   is   so   frequently   trotted   out   in   the   course   of   lectures   and   documentaries   that   it   begins   to sound   like   some   kind   of   litany   recited   as   an   article   of   faith;   which   is   pretty   much   all   it   is.   It   is   a   telling   of history   in   such   a   way   as   to   present   the   Christian   Faith   as   the   enemy   of   science.   It   is   guided   by   ideology rather   than   facts.   As   such   it   obscures   the   fact   that   intellectual   leaders   within   the   Lutheran   Church,   the original   Protestant   Church,   championed   Copernicus’   theory   and   transformed   it   from   an   idea   partly based   on   ideology,   to   a   theory   based   on   physics   and   strongly   supported   by   empirical   observation.    This fact   is   easily   demonstrated   by   the   historical   evidence,   but   the   evidence   usually   has   to   endure   a   second tier   of   unsubstantiated   claims.   These   matters   will   be   dealt   with   in   detail   below,   but   generally   they   arise from   a   dubious   projection   of   Galileo’s   experience   with   the   Roman   Catholic   Church   onto   the   situation within    the    protestant    Lutheran    Church;    or    from    a    projection    of    19th    century    North    American fundamentalist views onto the Lutheran Church of the 16th and 17th century. Martin   Luther   wrote   nothing   about   Copernicus’   heliocentric   theory.   His supposed   views   were   reconstructed   by   two   of   his   students   who   looked at   notes   they   wrote   decades   before   and   attempted   to   reconstruct   from them   what   they   thought   Luther   had   said   at   that   time.   Their   attempt   at reconstruction   was   published   in   a   book   called   Table   Talk.    Whatever   the views   of   Luther   on   Copernicus’   theory,   their   relevance   is   doubtful.   First, the   date   of   the   dinner   at   which   he   was   supposed   to   have   said   these things    was    before    the    publication    of    Copernicus’    book;    and    second, such   views   from   Luther   would   have   involved   him   in   trespassing   on   the turf of other faculties at his university.

George Rheticus

A   professor   from   Luther’s   university,   George   Rheticus,   was   given   generous   sabbatical   leave   to   visit Copernicus   and   remain   as   his   guest,   while   exploring   his   astronomical   theory   of   heliocentrism.   Rheticus published    a    summary    of    Copernicus’    theory,    Narratio    prima    (1594),    and    was    given    further    leave    to persuade   Copernicus’   to   publish   his   theory.   He   was   successful   and   personally   took   the   manuscript   to   the publisher.   Rheticus   later   sought   to   further   his   career   by   applying   for   a   position   at   Leipzig   University.   So impressed   by   Rheticus   was   Luther’s   right-hand   man,   Philip   Melanchthon,   that   he   stepped   in   to   help Rheticus   negotiate   his   salary   at   Leipzig.   The   result   was   that   Rheticus   became   the   highest   paid   professor at   Leipzig   University!   Some   have   speculated   that   Rheticus   left   for   Leipzig   because   of      persecution   by   the Lutheran Church. It doesn’t look like it to me.   From Maestlin to Kepler The    championing    of    Copernican    heliocentric    theory    then    passed    to    another    Lutheran    university    at Tubingen.   Here   Professor   Michael   Maestlin   enthusiastically   presented   Copernicus’   theory,   according   to his   young   student   Johannes   Kepler .   Kepler   took   up   the   challenge   and   in   the   “Student   Disputations” organised   by   the   staff   for   the   students,   argued   the   case   for   Copernicus.   Yet   even   at   this   early   stage Kepler   was   in   the   process   of   transforming   Copernicus’   theory.   Copernicus   believed   that   objects   in   the heavens   should   move   according   to   ideals   of   mathematical   perfection   -   in   perfect   circles   with   uniform motion.   Kepler   began   to   argue,   even   at   this   early   stage,   that   the   planets   moved   around   the   Sun   because of   a   physical   motivating   force   from   the   Sun.   Today   we   take   this   for   granted,   but   Kepler,   very   consciously, moved   astronomy   into   astrophysics.   Now,   thanks   to   Einstein,   we   understand   that   the   force   of   the   Sun’s mass curves the very fabric of space-time itself, forcing the planets to move in circles around it. The Determination of Kepler’s Career Path During   the   course   of   their   last   year,   the   faculty   at   Tubingen   usually   found   a   placement   for   their   students in   either   a   congregation   or   a   school.   A   placement   for   Kepler   as   a   teacher   of   mathematics   was   found   at   a school   in   Graz.   This   surprised   Kepler,   as   he   had   entered   Tubingen   in   the   belief   that   God   had   called   him to   be   a   parish   minister.   However,   Kepler’s   reason   for   this   belief   was   somewhat   skewed   by   his   damaged self-esteem   at   the   time.   He   had   imagined   that   God   would   have   called   him   to   be   a   prophet,   but   since   he was   such   a   miserable   wretch,   he   should   become   a   parish   minister.   This   view   of   himself   may   have   been generated   by   his   dysfunctional   family   of   origin   in   which   power   was   exercised   by   deprecation   of   another’s self-worth.      At   the   same   time,   Kepler’s   passion   for   astronomy,   and   his   clear   talent   in   that   area,   made   it clear   where   his   talents   lay.   At   the   time,   Christian   theology   in   the   West   followed   two   broad   streams:   that which   derived   from   the   ‘Book   of   Scripture’;   and   that   which   derived   from   the   ‘Book   of   Nature’.   The   faculty effectively   transferred   Kepler   to   the   other   stream.   Kepler,   himself,   came   to   understand   this   when   he spoke later that year of “astronomers as the priests of God interpreting the Book of Nature”. Tubingen’s Support for Kepler’s Heliocentrism Some   have   suggested   that   Kepler   was   expelled   from   Tubingen   before   his   final   exam   and   before   being awarded   a   degree;   and   that   this   was   his   punishment   by   the   Lutheran   Church   for   his   promotion   of heliocentrism.   This   view   is   untenable   for   a   number   of   reasons.   First,   there   was    no   final   exam,   nor   was there   a   degree   in   theology   to   be   awarded   to   the   students   in   their   last   year. ¹    Second,   why   would   the faculty   bother   finding   Kepler   a   paid   placement   if   they   just   wanted   to   get   rid   of   him?   Third,   why   would the   university   permit   Professor   Maestlin   to   continue   mentoring   Kepler   in   his   astronomical   theorising? Fourth,   why,   when   Kepler   returned   in   less   than   two   years   with   the   manuscript   of   his   first   book   promoting heliocentrism,   did   the   Senate   of   Tubingen   University   give   their   unanimous   approval   for   its   publication? Much   of   such   speculation   appears   to   have   arisen   in   an   attempt   to   project   onto   Kepler’s   story   the experience of Galileo Galilei with the Roman Catholic Church. The Influence of Maestlin and Hafenreffer The    unanimous    approval    of    the    Senate    of    Tubingen    University    for Kepler’s    book    was    subject    to    any    amendments    required    by    the University’s    most    senior    astronomer,    Professor    Michael    Maestlin. Since   Maestlin   was   an   enthusiastic   Copernican,   these   changes   were not   likely   to   be   great.   However,   Maestlin   became   concerned   about   the possibility    that    the    university’s    Prorector,    Dr    Matthias    Hafenreffer, was   opposed   to   Copernicus’   theory   and   that   there   may   be   troubled waters   ahead.   Maestlin   apparently   based   this   fear   on   the   fact   that Hafenreffer     continually     cracked     jokes     about     the     matter.     What Maestlin   did   not   appear   to   know   was   that   Kepler   and   Hafenreffer   had become   close   friends,   and   would   go   on   to   correspond   with   each   other for   the   rest   of   their   lives.   Kepler   was   able   to   assure   Maestlin   that Hafenreffer   himself   was   a   Copernican   at   heart.   Nevertheless,   in   this same    correspondence,    Kepler    revealed    to    Maestlin    that    he    had withdrawn   a   chapter   of   the   manuscript   of   Mysterious   Cosmos    at   Hafenreffer’s   request.   However,   the chapter   withdrawn   was   not   about   Copernican   theory,   but   about   the   harmonisation   of   Natural   and Biblical   Theology.   We   do   not   have   access   to   the   withdrawn   chapter,   but   if   it   was   an   earlier   version   of some of Kepler’s later writings it would appear to have been inflammatory. Kepler would go on to write: “To   whoever   is   too   stupid   to   understand   astronomical   science,   or   too   weak   to   believe   Copernicus   without affecting   his   faith,   I   would   advise   him   that,   having   dismissed   astronomical   discoveries   and   having   damned whatever   philosophical   opinions   he   pleases,   he   mind   his   own   business   and   betake   himself   home   to   scratch   his own dirt patch, abandoning this wandering about the world.” ⁵ Deriding   one’s   intellectual   critics   as   little   more   than   a   bunch   of   chooks   does   little   to   win   them   over. Kepler   would   also   argue   that,   as   the   Book   of   Scripture   involved   God’s   accommodation   to   the   simplest   of people,   whereas   the   Book   of   Nature    was   only   accessible   to   those   intellectually   gifted   by   God,   it   should   be Natural   Theologians   drawing   on   Natural   Philosophy   who   exercised   oversight   over   the   ponderings   of Biblical Theologians. This would truly have involved a “powershift”! If   such   ideas   about   theology   came   from   a   later   and   more   mellowed   Kepler,   one   can   only   guess   at   what he   wrote   in   the   withdrawn   chapter,   written   in   his   20s.   It   is   thus   easier   to   understand   why   an   older   and wiser Hafenreffer would have written to the young Kepler: “But   if   (may   Almighty   God   forbid   this)   you   should   wish   to   harmonize   those   hypotheses   with   Holy   Writ   openly and   fight   for   this   harmonization,   I   am   certainly   afraid   that   this   matter   may   result   in   dissension   and   strain.   In that    case    I    would    wish    that    I    had    never    seen    your    thoughts,    although    in    themselves    and    considered mathematically   they   are   splendid   and   lofty.   For   in   God’s   church   there   has   long   been   more   strife   than   is   good for   the   weak.   However,   I   don’t   know   where   I   am   being   carried   along   by   my   pen,   or   rather   by   my   brotherly affection   for   you.   Were   it   not   as   very   strong   and   very   sincere   as   it   is,   I   would   not   have   permitted   my   pen   such unfettered freedom.” ² Education   at   Tubingen   at   that   time   involved   traing   in   rhetoric   -   the   art   of   persuasion   through   reasoned argument   and   illustration   and   charm.   Clearly   Kepler   was   not   excelling   in   this   area,   and   was   not   likely   to win people over and influence them by his rhetorical skills. Still, that would be true of many geniuses. Hafenreffer’s   response   to   conflict   over   Copernican   theory   at   Tubingen   University   was   simply   to   suggest an open debate, and to invite Maestlin to take part. That’s the way academics deal with such issues.

Kepler Takes Astronomy into Astrophysics

Maestlin’s   influence   was   felt   in   another   way   which   has   had   much   longer   lasting   effect.   One   of   the   two main   themes   of   Kepler   in   Mysterious   Cosmos   was   the   so-called   polyhedral   hypothesis;   something   which Kepler   regarded   as   a   brainwave   that   came   to   him   while   teaching   mathematics   at      Graz.   He   had   noticed the   apparent   correspondence   between   lines   drawn   around   the   so-called   Platonic   solids   and   the   orbits   of the   then   known   planets.   The   other   main   hypothesis   was   that   of   the   physical   force   emanating   from   the Sun   which   motivated   the   planets   to   orbit   the   Sun.   As   a   mathematician,   Maestlin   became   extremely excited   by   the   polyhedral   hypothesis   and   in   his   recommendation   of   Kepler’s   book   to   the   Duke,   and   to the   University,   spoke   enthusiastically   of   the   ability   of   Kepler’s   mathematical   hypothesis   to   predict   the positions   of   celestial   bodies   a   priori,    rather   than   attempting   to   infer   a   hypothesis   from   observations.   In contrast,    Maestlin’s    response    to    Kepler’s    motive    force    argument    was    rather    discouraging.    Maestlin wrote: “I   do   not   reject   this   speculation   of   spirit   and   motive   virtue.   …   And   as   I   would   truly   say   what   I   think,   I   do   not reject, but my assent is really weak, indeed very many objections stand before me.” ³ A   reading   of   Mysterious   Cosmos   shows   that   much   more   space   was   given   in   the   book   to   the   polyhedral hypothesis   (19   out   of   22   chapters),   than   the   motive   force   argument.   One   has   to   ask   whether   this   was   the result   of   Maestlin   imposing   his   bias   on   his   student’s   work.   For   Kepler,   the   motive   force   argument   was linked   to   the   distance/orbital   period   relationship;   and   he   drew   a   comparison   with   the   way   in   which   light emanating   from   the   Sun   weakens   in   proportion   to   distance   from   the   Sun.   In   comparing   the   polyhedral hypothesis which came first in his book, with the motive force thesis which came second, Kepler wrote: “It   seems   to   me   unlikely   that   anyone   will   give   any   other   answer   than   that   this   fitting   of   the   motions   to   the spheres   is   very   neat,   a   wonderful   piece   of   God   the   craftsman.   Consequently,   if   one   or   other   argument   must   be accepted,   they   will   assent   to   the   second   argument   rather   than   to   the   one   from   the   solids,   as   being   more obviously acceptable,  even though the values still have a slight discrepancy from the Copernican ones.” ⁴ Clearly   Kepler   himself   favoured   the   motive   force   argument   over   the   polyhedral   hypothesis,   and   it   was this   motive   force   argument   which   moved   astronomy   into   the   realm   of   astrophysics.   Today   we   take   it   for granted   that   the   laws   of   physics   control   bodies   in   space.   However,   even   Copernicus   did   not   think   this   was so.   In   fact,   one   of   the   two   objections   that   Copernicus   had   to   the   earth-centred   notion   was   that   the celestial   bodies   did   not   move   with   uniform   motion   around   perfect   circles.   Copernicus’   belief   about   the motion   of   bodies   in   the   celestial   sphere   did   not   come   from   the   Bible,   but   from   the   ancient   Greek philosopher,   Aristotle.   Kepler’s   belief   that   a   physical   (as   in   physics)   force   motivated   the   planets   is   first found   in   his   speeches   in   the   Student   Disputes   of   his   university   days.   It   is   published   in   his   first   book, Mysterious Cosmos; and in his later work, New Astronomy, he grounds his argument on the orbit of Mars.

In Summary

Kepler   was   never   persecuted   by   the   Lutheran   Church   for   his   support   of   Copernican   theory.   Indeed,   the Senate   of   the   Lutheran   university   at   Tubingen   gave   unanimous   support   to   his   first   book   on   the   subject. Both   the   senior   astronomer,   Michael   Maestlin,   and   the   Prorector,   Matthias   Hafenreffer,   were   supporters of    Copernicus’    theory.    These    intellectual    leaders    transformed    Copernicus’    theory    from    a    concept partially   based   on   ancient   Greek   mythology   about   motions   of   heavenly   bodies   to   a   theory   based   on physics and physical forces. Why aren’t we told the truth? Footnotes 1)   “  The   overwhelming   majority   of   students   remained   in   the   Stift   and   continued   their   theological   studies at   the   faculty   of   theology   until   they   could   be   offered   a   position   in   a   parish   or   a   school,   although   a   few completed   their   doctorate   in   theology.   …   The   study   of   theology   did   not   have   a   fixed   duration,   and   it could   not   be   concluded   by   a   formal   university   examination   other   than   a   doctoral   promotion.   …   Since there   was   no   theology   degree   as   such,   and   an   examination   did   not   mark   the   end   of   this   period   of   study until    the    seventeenth    century    [J.    Hahn    and    H.    Mayer,    Das    evangelische    Stift    in    Tubingen,     108],    it    is misleading    to    remark,    as    several    commentators    have    done,    that    Kepler    left    Tubingen    without completing      his      degree.      Charlotte      Methuen.      Kepler’s      Tubingen .       Stimulus      to      a      Theological Mathematics. Ashgate Publishing Company.1998.p52. 2)   Quoted   in   James   R   Voelkel   The   Composition   of   Kepler’s   Astronomia   nova .   Princeton   University   Press. 2001. p.65. 3) Ibid p.67 4) Quoted by Voelkel, ibid p.55 5)   Quoted   by   Charlotte   Methuen   in   Science   and   Theology   in   the   Reformation.    Studies   in   Interpretations   of Astronomical Observations in Sixteenth Century Germany . T&T Clark 2008. p.86

Science and Faith Today

From   ancient   times,   human   beings   have   looked   at   Nature;   the   world   around   them   and   the   skies above   them;   and   wondered   about   the   how   and   why   of   the   universe.   How   does   it   work?   And   why   are we    here?    In    the    beginning,    issues    of    science    and    faith    were    intertwined.    Earthquakes    were interpreted   as   the   disapproval   of   the   gods.      Comets   were   seen   as   omens   of   ill-fortune.   Over   the course    of    time,    answers    to    the    how    question    have    revealed    that    earthquakes    occur    because    of movement    in    the    Earth’s    tectonic    plates,    Comets    are    not    omens,    but    “dirty    snowballs”    in    very elongated    orbits.    As    they    approach    the    Sun,    comas    and    tails    form    as    the    comet’s    volatiles    are vaporised.   (It   is   interesting   to   note   that         when   Johannes   Kepler   tried   to   explain   comets   in   this   way, Galileo   accused   him   of   dabbling   in   the   occult!)   Some   have   tried   to   shift   blame   for   primitive   ideas about   the   cosmos   entirely   onto   religion,   but   these   primitive   ideas   were   just   as   much   the   result   of primitive   science.   Just   as   science   has   moved   along,   so   has   religion;   at   least   among   Christians   in   the West. There   is   a   good   reason   why   the   Christian   Faith   in   the   West   has   moved   along   with   science.   From   its very   beginnings,   Christians   have   turned   to   Nature   as   a   means   of   revelation.   Inheriting   from   Judaism those   psalms   which   maintain   that   “the   heavens   declare   the   glory   of   God”,   Christian   Faith   moved   on   to an   understanding   of   a   God   who   was   revealed   through   human   nature.   Speaking   of   Jesus   of   Nazareth, the   author   of   the   first   letter   of   John   expressed   the   idea   saying,   “We   declare   to   you   what   was   from   the beginning,   what   we   have   heard,   what   we   have   seen   with   our   eyes,   what   we   have   looked   at   and touched   with   our   hands,   concerning   the   word   of   life”.   For   these   early   Christians,   revelation   was   a physical sensory experience. In   the   12th   century,   Hugh   of   St   Victor   maintained   that   if   God   was   indeed   the   Creator,   then   “Nature   is a   book   written   by   the   finger   of   God.”   There   thus   arose   in   the   Christian   West   the   belief   that   God   was revealed   both   in   the   Book   of   Scripture   (the   Bible),   and   the   Book   of   Nature   (science).   This   “theology   of the   two   books”   was   well   established   by   the   time   of   Galileo   and   Kepler.   Galileo   outlined   it   most precisely   in   his   Letter   to   the   Grand   Duchess   Christina;    and   Kepler   described   astronomers   as   priests   of God   interpreting   the   Book   of   Nature.   It   was   for   this   reason   that   theological   universities   during   the time   of   Galileo   and   Kepler   taught   not   only   theology,   but   mathematics,   astronomy   and   physics   ...   and more.   And   it   was   probably   for   this   reason   that   so   many   scientific   discoveries   were   made   by   clergy, whether    Catholic    or    Protestant.    Against    this    background,    one    can    see    how    North    American fundamentalism,   which   believes   in   the   Bible   alone   as   a   means   of   revelation,   has   cut   itself   off   from mainstream Christianity. The   Christian   Church   continues   to   produce leaders   in   scientific   advance.   For   example, the    Jesuit    priest    and    astronomer,    George Lemaitre,     proposed    the    “Big    Bang”    theory for the origin of the universe. Anglican   rector,   the   Rev   John   Michell,    first proposed   Black   Holes    under   the   title   “Dark Stars”.   Black   holes   are   objects   of   such   great mass    and    gravity    that    not    even    light    can escape from them. Using statistical methods, Michell first proposed that binary stars are gravitationally bound. Michell’s       genius       was       not       confined       to astronomy.   He   was   a   leader   in   geology,   being the   first   to   explain   that   earthquakes   resulted from    waves    generated    by    movements    of    the Earth’s strata. Michell’s    next    area    of    achievement    was    in    magnetism     in    which    he showed how  to develop an artificial magnet. Michell’s   legacy   continued   beyond   his   death.   He   had   devised   an   instrument   for   the   measurement   of the   Earth’s   mass,   but   died   before   he   could   use   it.   His   close   friend,   Henry   Cavendish,   went   on   to   use   it as   part   of   the   Cavendish   experiment.   Michell   had   also   built   a   number   of   telescopes   for   his   own   use. One   of   these   was   a   30   inch   reflecting   telescope.   After   Michell’s   death   it   was   aquired   by   William Herschel.   Unfortunately   the   primary   mirror   was   damaged,   but   Herschel   used   Michell’s   telescope   as   a model by which he built his own. The   notion   that   God   is   revealed   through   Nature   is   called   “Natural   Theology”,   and   today   there   are some guiding lights in this field. One thinks of: Professor   Alister   McGrath,   a   former   atheist,   with   a   Ph.D.   in   molecular   biology   and   a Doctor of Divinity. McGrath is a prolific author who has a website. Professor     John     Polkinghorne     is     a     former     Cambridge     professor     of mathematics   and   physics   who   became   an   Anglican   minister   and   is   also   a prolific writer on science and theology. He has a website .   One    should    not    forget    the    Americans    either,    like    Dr    Francis    S.    Collins, former   head   of   the   Human   Genome   Project,   and   enthusiastic   Christian.   He founded    the    BioLogos    Foundation     to    help    Christians    understand    the compatability of Evolution and Christian Faith.

The Christian Faith

In   this   area   of   the   website,   I   intend   to   contribute   a   number   of   essays   on   the   Christian   Faith   in   its   earliest   form. Though    the    Christian    Faith    was    once    the    common    religion    in    the    West,    one    can    no    longer    assume    an understanding   of   it   amongst   the   general   population.   For   someone   standing   on   the   outside,   it   can   be   easy   to misconstrue   the   nature   of   the   Faith.   Movements   like   Fundamentalism,   particularly   in   North   America,   may sometimes   seem   to   be   mainstream   when,   worldwide,   they   are   not.   The   universal   failure   of   the   Roman   Catholic Church   to   deal   with   paedophilia   has   to   be   seen   in   the   context   of   the   major   divisions   of   the   Church.   Attitudes toward   the   writings   so   central   to   the   Faith   (i.e.,   the   Bible)   are   often   forged   with   little   understanding   of   the   way   in which   the   many   documents   were   written,   transmitted,   collected   and   approved.   The   world-view   of   the   authors needs   explanation   and   translation.   Whether   you   are   a   practitioner   of   the   Faith,   or   someone   on   the   outside   who needs   some   knowledge   of   it   in   order   to   work   efficiently   in   administration   or   diplomacy,   I   hope   you   will   find these essays helpful. My   background   is   that   of   a   practitioner   of   the   Faith.   I   am an    ordained    minister    of    a    major    Protestant    Church    in Australia,   although   now   retired.   However,   my   theological education    came    from    doing    a    four    year    postgraduate degree   in   Divinity   at   the   University   of   Sydney,   Australia   in the   late   1970s   and   early   1980s.   The   University   is   a   secular university    and    the    degree    was    available    regardless    of religious faith. Whether    you    are    a    Christian    wanting    to    reflect    more deeply   on   some   issues   of   faith,   or   a   person   looking   in from   the   outside   who   just   wants   a   better   understanding of   Christianity   for   whatever   reason,   I   hope   you   will   find my   essays   interesting.   The   topics   will   be   listed   as   sub- menus     under     the     “Christian     Faith”     button     in     the navigation    bar    above.    Some    topics    have    not    yet    been completed     so     those     sub-menu     items     will     not     lead anywhere for the time being.