Sol Lucet Omnibus - ESO

This stunning image of a
nebula is a snapshot of
one small segment of its
life. New stars are forming
deep inside, which will
one day shine brightly.
and filling the gaps with reasoning
we have achieved an understanding
of the lives of stars and the
processes that take place in them.
Stars with a golden glow
The evolution of an individual
star is only a small sub-plot in
the grand story of our Milky Way.
The Sun was not among the first
stars that populated the Milky
Way. Earlier generations of stars
formed from gas clouds, lived their
lives synthesising — by nuclear
fusion — many of the elements of
the periodic table up to iron, and
finally exploded into the interstellar
medium returning matter back to
the gas clouds.
During such an explosion some
elements even heavier than iron
were synthesised. This is, for
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instance, the only way that the
element gold can be produced
in the Universe. The existence
of elements like silver, gold and
uranium as well as carbon, oxygen
and nitrogen on our Earth suggests
that the Solar System formed
from a gas cloud enriched by the
gases expelled into the interstellar
medium by previous generations of
stars. Our Sun was not always there
and will not always be there either.
We could not exist without the
Sun, but it took many generations
of stars to produce the elements
we need for our bodies and in our
everyday lives. We are not isolated
from the rest of the Universe,
interacting only with our star: we
rely on a galaxy, a web of stars
linked by continuous creation and
death. The formation of the Sun
and the planets around it is not the
last word of our galaxy, or of the
Universe. New stars have continued
to form since the birth of our Solar
System!
Earth-shattering science
Earthquakes are not only incredibly
powerful and destructive, they
challenge our common notion that
the ground beneath our feet is
stable. The continents of Africa and
South America were once attached,
as a glance at the world map shows.
There is sufficient evidence that
landmasses are moving across
the globe! As the continents drift,
they sometimes push against each
other, and it is the release of this
accumulated stress that causes
earthquakes, a scientific explanation
that also stretches the imagination
as we see the slow, but inexorable
progress of two juggernauts
lumbering towards a final cataclysm.
The Earth, our home, is not a
finished project, even if it appears
sufficiently steady for our practical
purposes. There is no reason for the
Earth’s surface to stop moving just
because we have started building
houses or drawing national borders
on a map. I am fascinated by the
fact that we are living on a celestial
object that evolves just like the rest
of the Universe.
The indifference of the planet’s
crust to our presence is a sobering
thought, stressing our insignificance
even on the planetary scale. Some
people see the objectivity of
science as a just cold bundle of
information. They may contrast it
with the ancient explanation for
earthquakes as a punishment of a
supernatural power — placing us
in a privileged position that might
deserve such an attention. It is a
remarkable human achievement
to understand earthquakes as a
consequence of the journey of
landmasses across the globe. I
find this explanation far more
imaginative than the ancient view
which is strongly challenged by the
fact that earthquakes also occur on
other planets where nobody lives.
Past, present and future
We are floating in an ocean of
culture that implicitly assumes that
creation is a completed process.
Our great illusion is to regard
the Earth as a single finished
product; the lands, plants and
animals created for our use. In this
solipsistic picture the rest of the
Universe is there only to make our
show on the Earth possible. This is
a huge obstacle to understanding
nature and loving our planet as it
is. It also does not help us when we
try to save the Earth. Our world had
a past before us and it is expected
to have a future. Evolution is an
ongoing process and no phase of
it is privileged to be the ultimate
form.
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Left image:The Sun will
produce a planetary
nebula when its
nucleus runs out of
fuel. Right image: The
Earth exists within an
evolving Universe, so
is it any wonder that it
experiences changes,
such as earthquakes?