The Hellenic Navy (HN) (Greek: Πολεμικό Ναυτικό, Polemikó Naftikó, abbreviated ΠΝ) is the naval force of Greece, part of the Greek Armed Forces. The modern Greek navy has its roots in the naval forces of various Aegean Islands, which fought in the Greek War of Independence. During the periods of monarchy (1833–1924 and 1936–1973) it was known as the Royal Navy (Βασιλικόν Ναυτικόν, Vasilikón Naftikón, abbreviated ΒΝ).The total displacement of all the navy's vessels is approximately 150,000 tons.The motto of the Hellenic Navy is "Μέγα το της Θαλάσσης Κράτος" from Thucydides' account of Pericles' oration on the eve of the Peloponnesian War. This has been roughly translated as "Great is the country that controls the sea". The Hellenic Navy's emblem consists of an anchor in front of a crossed Christian cross and trident, with the cross symbolizing Greek Orthodoxy, and the trident symbolizing Poseidon, the god of the sea in Greek mythology. Pericles' words are written across the top of the emblem. "The navy, as it represents a necessary weapon for Greece, should only be created for war and aim to victory."...............The Hellenic Merchant Marine refers to the Merchant Marine of Greece, engaged in commerce and transportation of goods and services universally. It consists of the merchant vessels owned by Greek civilians, flying either the Greek flag or a flag of convenience. Greece is a maritime nation by tradition, as shipping is arguably the oldest form of occupation of the Greeks and a key element of Greek economic activity since the ancient times. Nowadays, Greece has the largest merchant fleet in the world, which is the second largest contributor to the national economy after tourism and forms the backbone of world shipping. The Greek fleet flies a variety of flags, however some Greek shipowners gradually return to Greece following the changes to the legislative framework governing their operations and the improvement of infrastructure.Blogger Tips and Tricks
This is a bilingual blog in English and / or Greek and you can translate any post to any language by pressing on the appropriate flag....Note that there is provided below a scrolling text with the 30 recent posts...Αυτό είναι ένα δίγλωσσο blog στα Αγγλικά η/και στα Ελληνικά και μπορείτε να μεταφράσετε οποιοδήποτε ποστ σε οποιαδήποτε γλώσσα κάνοντας κλικ στη σχετική σημαία. Σημειωτέον ότι παρακάτω παρέχεται και ένα κινούμενο κείμενο με τα 30 πρόσφατα ποστς....This is a bilingual blog in English and / or Greek and you can translate any post to any language by pressing on the appropriate flag....Note that there is provided below a scrolling text with the 30 recent posts...Αυτό είναι ένα δίγλωσσο blog στα Αγγλικά η/και στα Ελληνικά και μπορείτε να μεταφράσετε οποιοδήποτε ποστ σε οποιαδήποτε γλώσσα κάνοντας κλικ στη σχετική σημαία. Σημειωτέον ότι παρακάτω παρέχεται και ένα κινούμενο κείμενο με τα 30 πρόσφατα ποστς.........

Wednesday, September 19, 2012

The surface of Mercury..[ 2932 ]

Mercury probe points to different origin for 1st planet

By Matt Smith, CNN
September 18, 2012 -- Updated 2250 GMT (0650 HKT)
High levels of magnesium and sulfur on the surface of Mercury, suggest its makeup is far different from other planets.
High levels of magnesium and sulfur on the surface of Mercury, suggest its makeup is far different from other planets.

(CNN) -- X-ray data from NASA's MESSENGER probe points to high levels of magnesium and sulfur on the surface of the planet Mercury, suggesting its makeup is far different from that of other planets, scientists say.
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The unmanned orbiter has been beaming back data from the first planet for a year and a half. Readings from its X-ray spectrometer point to a planet whose northern volcanic plains formed through upwellings of rocks more exotic than those often found on the Earth, the Moon or Mars, said Shoshana Weider, a researcher at the Carnegie Institution of Washington.
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"Before this MESSENGER mission, a lot of people assumed it was very like the Moon -- it's dark, it's grey," Weider said. But while the Moon's surface formed when light materials floated to the top of an ocean of molten rock, the low level of calcium on Mercury indicates that didn't happen there.
"This gives us clues to the kind of precursor materials that accreted to form Mercury, in an extremely oxygen-poor environment," Weider said.
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The concentration of sulfur on the surface is about 10 times that seen on Earth, she said. And while Mercury's iron core "makes up a huge amount of the planet," very little is found at the surface.
The northern region of volcanic plains differs significantly from the surrounding portion of Mercury, where the surface -- as dated by the number of craters -- is about a billion years older, Weider said.
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The results were published in the latest issue of the Journal of Geophysical Research, a peer-reviewed publication of the American Geophysical Union. Weider and her co-authors studied 205 different readings from the spectrometer to produce their results.
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MESSENGER -- an acronym for the Mercury Surface Space Environment, Geochemistry and Ranging mission -- has been orbiting Mercury since March 2011. It's only the second spacecraft to reach the planet and the first to circle it.
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It's about 5% the size of Earth and revolves around the sun every 88 days. It rotates very slowly -- once every 58 Earth days -- and the surface temperature on the day side can reach 800 degrees Fahrenheit (425 C), according to NASA.
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