Marzo - Sardinews

In fact, even non specialists have some familiarity
with astronomical images, those
obtainable with amateur telescopes, but
also those coming from instruments such
as the Hubble Space Telescope. But a
part from the fascinating aspect, which is
rather intriguing, modern astronomy is
one of the most promising discipline in
our understanding of Nature. Modern
astronomical observations allows us to
investigate regions of the Universe which
are located billions of light-years from us,
which in turn implies that we are looking
billions of years back in the past. However,
most people are not familiar with all
the various branch of modern astronomy.
We know that in general cosmic sources
of radiation emits electromagnetic waves
in the whole spectrum, so from radio
waves to infrared, visible light, ultraviolet,
x-rays and gamma rays. We are familiar
with the optical band (the visible-light
band) because this is the band in which
our eyes do work. But this band is only a
small portion of the electromagnetic spectrum,
so astronomical observations in
this band only would produce rather limited
information, because many cosmic
sources emit a huge amount of radiation
in other bands. “Radio astronomy” is a
particular branch of astronomy devoted
to the observation of radio waves coming
from various source in the Universe. So,
the instruments that we use in this case,
the “radio telescopes”, are rather similar
to the parabolic antennas that we can see
these days on top of our houses, which in
turn are devoted to receive human generated
radio waves, such as TV channels.
They are similar but rather different for
their size and their technology.
It is obvious to ask what we are learning
with radio astronomy in addition to what
we already know from traditional astronomy.
Let me cite an example which is related
to the activity of my research group,
and represents an important verification
test of General Relativity and Gravity
theories. Astronomical observations in
the radio band, carried out with the Parkes
radio telescope, in Australia, by our group
led to the discovery of a peculiar stellar system,
the so called “Double Pulsar”. This
binary system promises itself to be an extraordinary
laboratory for accurate tests of
the Einstein’s theories on Gravitation. For
such a discovery, our team and our international
collaborator were awarded by the
European “Descartes Prize” in 2005, and
our PhD student, who was involved in the
project, Marta Burgay (now research staff
in Cagliari), is now one of the most awarded
“young scientist” in the world. So, here
the point is: which is the actual utility of
these investigations, a part form the obvious
advancement of our understanding of
Nature? After all we already know that
by treating the orbits of artificial satellites
with Einstein formulas instead of Newton
formulas, we get the GPS system working
properly, so why we need to investigate
further the Einstein theories? Well, from
the above example, we just learn that any
improvement of our knowledge of the Nature
laws represents in any case the basis of
the improvement of our quality of life. It
might be not clear to not-specialists why
we should spend additional effort into the
The sky above us
verification of Einstein laws, considering
that they work so well for advanced applications
like the GPS system. In this
respect, we should remind that alternative
theories of Gravity now exist whose predictions
differ from Einstein’s predictions by a
rather small measurable effects, but whose
impact on cosmology, and so on the Universe
evolution, are significant. And in addition
to this, we should not exclude the
possibility that such theories (or an accurate
verification of Einstein theories) might
have further applications into technology,
and so on our quality of life.
We should hope that the attention to the
SRT project by the national and regional
Governments, which was so high so far,
will be keep going in the future, though
the generally economy is the Country is
encountering some difficulties. The value
of such facility is around 60 Million Euros,
and according to what we observe in
Europe for other similar structures, the
annual running costs are expected to be
of the order of the 5% of the value, so
about 3 Million Euros per year, including
the personnel cost. This is a significant
amount of money, but the return of such
investment in term of research and development
and training is very high, which
in turn represents a key for a further grow
of our Country. This facility will be part
of an international network of excellence,
so the opportunity to capitalise the presence
in Sardinia of such instruments represents
a challenge for the Island.
marzo 2012
23