!! spellx done
181  An Asteroid Into the Sun
     May Have Glazed Moon Rock
     The Washington Post  December 6, 1969

     For many scientists occupied with the analysis of lunar samples,
the Apollo flights are spaced too closely together to keep up with.  
They scarcely scratch the surface in their examination of materials
returned by Apollo 11 before being inundated with the next batch.
Certainly, they have far too little time to develop well-pondered
theories to guide the next stage of lunar exploration.

     The biological oriented scientists do have one simple plea: for 
samples less heavily contaminated with rocket exhaust and other 
terrestrial pollutants.

     Apollo 12 nevertheless did return some precious cargo whose 
collection was guided by questions provoked by Apollo 11.  These are the
"documented samples" which were carefully photographed in place before
being picked up.  As Cornell University astrophysicist Thomas Gold
pointed out in an article in Science magazine, some of these rocks may
bear a record of fluctuations in the sun's radiation about which we
have no other direct evidence.

     His speculations were based on 17 closeup stereophotographs of the
lunar surface.  These showed more detail of the fresh soil than could
be seen by eye. Dr Gold was impressed by the occurrence of glaze 
patches on clumps of soil near the centers of small craters.

     The pictures suggest that the glazing tends to be off center.  
Unfortunately, the orientation of pictures of different craters was not
recorded, so they cannot be compared to see if the glazing points 
toward a common direction; this should be available from Apollo 12.

     Glassy beads have been found within many lunar rocks and clumps of
soil, and different sources of energy for melting them are being
debated.  Possible sources include lava sprays and meteorite impact.
(The moon has no atmosphere to heat an incoming meteorite by
friction.) Dr. Gold reviews and negates a number of theories to
account for the distribution of glazed patches -- splashing, exposure
by erosion, or formation by the impact that makes a crater.  He
is left with the conclusion that the glazing results from sudden
flashing of radiant energy from a source in the lunar sky within the
last 30,000 years -- the estimated upper limit of the time for erosion
of the glaze by new micro-meteorites.  Small craters would have a
focussing effect that could heat objects at the center some 20 per
cent hotter than the flat ground.  The flash would be so intense that
the sun is the only plausible source.

     The event would have been a solar flare of about 100 times normal
intensity for about one minute.  This represents more than a thousand
fold more energy than has been observed in solar flares to date, and 
might therefore have quite a different mechanism.  This energy is the
equivalent of an hour's extra sunshine.  Delivered in a short time to
the lunar surface, it could glaze unshielded lumps but should be 
buffered by the earth's atmosphere so as to minimize the effects on our
own surface, except for the triggering of forest fires or superficial
burns and blinding at high altitudes.

     One suggested mechanism is the infall of an asteroid or comet
into the sun.  Such events would be very rare, and astronomical 
observations should enable us to predict them.  On the other hand, we 
know very little about the process that regulates the stability of the 
sun and other stars.  The flash might have been a minor nova, of a kind 
we are unable to recognize by conventional astronomy.

     Thus the moon may give us a record of the long-term behavior of
the sun which is crucial to the viability of our own planet.
----------------------------------------------------------------------