Image via WikipediaApparently one of the largest experiments to date is currently being realized at the deepest point of the Mediterranean Sea. The experiment, known as “The Well of Inousses” or “Calypso Deep” is said to be located near Pylos.
For those who are not aware, the Calypso Deep is an area in the Ionian Sea off the west coast of Greece. Known as the deepest part of the Mediterranean Sea, it has a depth of 5,267 meters, while the average depth of the Mediterranean is only averaged at 1,500 meters. The Deep is located where the African Tectonic Plate slides under the Eurasian Plate, creating what is known as the Hellenic Trench.
Press reports said that astronomy and telescope construction in the depths of the sea are being conducted. It is an experiment of neutrino detection, called NESTOR (its name comes from the ancient king of the area), which predicts the presence of a huge telescope of 12 stages with a diameter of 32 meters and a total height of 330 meters, taller than the Eiffel Tower.
Through the experiment, a new kind of astronomy is set to emerge, beyond the sky and way beyond the existing scientific knowledge, or so reports claim. Professor of the University of Athens and chief of the program Leonidas Resvanis and his team expect the unexpected, trying to map the most primitive and strange material particles, known as neutrinos.
A neutrino is an elementary particle that usually travels close to the speed of light is electrically neutral and is able to pass through ordinary matter almost unaffected. This makes neutrinos extremely difficult to detect. Neutrinos have a very small, but nonzero mass. They are denoted by the Greek letter ν.
The NESTOR (Neutrino Extended Submarine Telescope with Oceanographic Research), is a tower of 12 hexagonal floors of 32 m diameter with highly sensitive photomultipliers of large surface area at the corner points (168 in total for phase 1). Each floor is located above the next at vertical intervals of 20 m. NESTOR will detect the Cherenkov radiation produced by muons in a large volume of transparent matter, water. For neutrinos with energy less than a few TeV, one must look for muons that are upcoming, ie their parent neutrinos have traversed the Earth. The muons are produced by neutrinos or by atmospheric interactions of cosmic rays. Though the muon is a very penetrating particle and can traverse hundreds or even km of water, its range in rock is comparatively short. For neutrinos with energies larger than a few TeV, one can look for downcoming muons because there are comparatively few cosmic rays at these extreme energies. This is the reason for going deep underwater; for neutrino energies less than a few TeV, the few kilometers of water above the detector act as a shield against cosmic rays and reduce this cosmic rate caused background by a factor of one million. NESTOR will investigate a wide range of physics topics such as:
- High-energy neutrino astronomy, namely detecting neutrinos produced by galactic X-ray binaries, black holes or extragalactic sources, such as the active galactic nuclei (AGNs) et.c
- Neutrinos that are produced from the annihilation of dark matter particles, SUZY particles et.c.
- Neutrino oscillations (i.e. weighting of the neutrinos), using neutrinos produced in the atmosphere.
- Neutrino oscillations, using neutrinos from a particle accelerator.
There are only four neutrino related deep-water experiments in the world;
- AMANDA in the South Pole
- BAIKAL in Baical Lake
- NESTOR of S.W. of Peloponnese
- ANTARES off Marseilles
NESTOR takes advantage of the unique fact that is deployed near the deepest part in Europe (depth up to 5200m). At a distance of about 14 km off the shore, at water depth of 4000m there is a fairly large abyssal plane that is perfectly suited for several deep-sea installations. In addition, the completely sheltered Bay of Navarino is very close to this offshore location (18 nautical miles) and has maximum water depth of about 60m. Further, within a distance of few miles from the deep location, there are three natural harbours (Methoni, Port Loggo (in the island of Sapienza) and Schiza)The small city of Pylos lies at the entrance of the bay. This combination of a protected, comparatively shallow bay for preliminary test operations with a deep-water site so close to shore seems to be optimal for the NESTOR research work.
In fact this is a unique site in Europe. The most important requirements for a deep underwater neutrino telescope are: Clear water (i.e. water with small light attenuation coefficient), deep site (to filter out the atmospheric muons), proximity to the shore (to use a short electro-optical cable to power the detector and transfer the data to shore), low velocity underwater currents (for minimal mechanical stress on the detector), flat and wide sea bottom (to permit further expansion) and stable geological characteristics (for long life time of the detector) PLUS proximity to harbours for safety and easy operations at sea. In short the unique advantages that the selected site provides are:
Proximity of the deep sea to the shore
Proximity of the deep sea to the shore
The existence of a data highway with an electro-optical cable
The existence of the bay of Navarino for continuous testing of components
The selected site fulfils these requirements. We have designated as the NESTOR/LAERTIS site, a location with co-ordinates 36*37.5'N, 21*34.5'E, in the middle of the deep underwater basin (called the NESTOR basin) which has a gentle slope.
The program with NESTOR, is co-sponsored by the General Secretariat for Research and Technology and OECD (Organisation for Economic Co-operation and Development), and according to reports aims at creating a new map of the sky, studying high-energy neutrinos, a form of radiation which has not been studied at all and the properties of which may utterly change the conception concerning the creation of the universe.
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