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, October 7, 2009

The rings around Saturn... [ 454 ]

Scientists discover massive ring around Saturn

(CNN) -7.10.09- Scientists at NASA have discovered a nearly invisible ring around Saturn -- one so large that it would take 1 billion Earths to fill it.

NASA's Spitzer Space Telescope has spotted a massive, nearly invisible ring around Saturn.

NASA's Spitzer Space Telescope has spotted a massive, nearly invisible ring around Saturn.

The ring's orbit is tilted 27 degrees from the planet's main ring plane. The bulk of it starts about 3.7 million miles (6 million km) away from the planet and extends outward another 7.4 million miles (12 million km).

Its diameter is equivalent to 300 Saturns lined up side to side. And its entire volume can hold one billion Earths, NASA Jet Propulsion Laboratory said late Tuesday.

"This is one supersized ring," said Anne Verbiscer, an astronomer at the University of Virginia in Charlottesville.

Verbiscer and two others are authors of a paper about the discovery published Wednesday in the journal Nature.

The obvious question: Why did it take scientists so long to discover something so massive?

The ring is made up of ice and dust particles that are so far apart that "if you were to stand in the ring, you wouldn't even know it," Verbiscer said in a statement.

Also, Saturn doesn't receive a lot of sunlight, and the rings don't reflect much visible light.

But the cool dust -- about 80 Kelvin (minus 316 degrees Fahrenheit) -- glows with thermal radiation. NASA's Spitzer Space Telescope, used to spot the ring, picked up on the heat.

One of Saturn's moons, Phoebe, orbits within the ring. As Phoebe collides with comets, it kicks up planetary dust. Scientists believe the ice and dust particles that make up the ring stems from those collisions.

The ring may also help explain an age-old mystery surrounding another of Saturn's moons: Iapetus.

Astronomer Giovanni Cassini, who first spotted Iapetus in 1671, deduced the moon has a white and dark side -- akin to a yin-yang symbol. But scientists did not know why.

The new ring orbits in the opposite direction to Iapetus. And, say researchers, it's possible that the moon's dark coloring is a result of the ring's dust particles splattering against Iapetus like bugs on a windshield.

"Astronomers have long suspected that there is a connection between Saturn's outer moon Phoebe and the dark material on Iapetus," said Douglas Hamilton of the University of Maryland in College Park -- one of the three authors reporting on the findings in the journal Nature.

"This new ring provided convincing evidence of that relationship."
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