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.........

Sunday, July 11, 2010

Spacecraft. "Rosetta"-Asteroid "Lutetia"..[ 1421 ]

4osetta probe passes Asteroid Lutetia

BBC.,Saturday, 10 July 2010 22:00 UK
By Jonathan Amos
Science correspondent, BBC News
Lutetia (ESA) 
Lutetia at closest approach - distance of 3,162km
Europe's Rosetta space probe has flown past the Asteroid Lutetia, returning a stream of scientific data for analysis.
The huge rock - about 120km in its longest dimension - is the biggest asteroid yet visited by a satellite.
Pictures showed Lutetia to be quite irregular in shape, its surface marked by a number of wide impact craters and even some intriguing grooves.
Rosetta's encounter with the asteroid occurred some 454 million km from Earth, beyond the orbit of Mars.

Scientists hope the data will help them determine Lutetia's true nature.
"The pictures are majestic; they take my breath away," Professor David Southwood, the European Space Agency's director of science, told BBC News.

Earth-based telescopes have had great difficulty in classifying Lutetia.
Some observations have suggested it is a very primitive body, little changed since its formation (a so-called C-type asteroid).

Other measurements, though, have also spied what appear to be metals in its surface, indicating the rock might have undergone a greater degree of evolution (M-type asteroid).

Lutetia might even be the fragmented remains of a much larger asteroid smashed apart in a great collision.


Lutetia (ESA) 
Rosetta took this image as it moved away from the asteroid
Rosetta will attempt to resolve these issues once and for all.
Nearly all of the Rosetta mission's instruments were switched on for a period of several hours around closest approach (1544 GMT; 1644 BST; 1744 CEST).

Multi-wavelength cameras and spectrometers, magnetic field and plasma experiments, dust instruments, a radio science experiment - all were tasked with gathering as much information as possible as the spacecraft whizzed by at the relative speed of 15km/s and a minimum distance of 3,162km.

Scientists say it will be some days before they can start to make some definitive statements about Lutetia's origins. 

THE ROSETTA PROBE MAKES ITS CLOSE PASS OF ASTEROID LUTETIA

The location of the flyby in the Solar System (BBC)
Asteroids are the ancient remnants left over from the formation of the Solar System

Most are made of rock, but some are also composed of metal, mostly nickel and iron

Their sizes range from small boulders to objects that are hundreds of km in diameter

Most asteroids reside in the vast region of space that exists between Mars and Jupiter
Jonathan.Amos-INTERNET@bbc.co.u
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