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, October 23, 2011

Satellite re-enters Earth's atmosphere...[ 2510 ]

German satellite re-enters Earth's atmosphere

The Earth is seen from aboard the International Space Station in this handout picture from NASA in August
















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October 23, 2011 



The Roentgen Satellite (ROSAT), an x-ray observatory, made its re-entry to the earth's atmosphere between 0145 GMT and 0215 GMT on Sunday, the German Aerospace Centre (DLR) said in a statement.
A German satellite the size of a car re-entered the Earth's atmosphere early Sunday, officials said, adding they did not know yet if any debris had hit the Earth.
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The Roentgen Satellite (ROSAT), an x-ray observatory, made its re-entry between 0145 GMT and 0215 GMT on Sunday, the German Aerospace Centre (DLR) said in a statement.
"There is currently no confirmation if pieces of debris have reached Earth's surface," the statement added.
According to estimates cited last week, as many as 30 individual pieces weighing a total of 1.7 tonnes could reach the surface of the Earth.
But Andreas Schuetz, spokesman for the DLR, said they would have to "wait for data in the next days" to know when and where the debris could fall.
He said they did not currently know how far it was from the Earth.
Last week, DLR officials said ROSAT was expected to return to Earth between October 22 and 23, travelling at a speed of around 28,000 kilometres (17,000 miles) per hour.
, which heats up the Earth's atmosphere, increases the atmospheric drag and makes it hard to estimate the date of re-entry.
As the re-enters the atmosphere, the x-ray observatory would break up into pieces, some of which will burn up, they said.
"The largest single fragment will probably be the telescope's mirror, which is very heat resistant," it added.
However, statistically speaking, there is very little danger to humans from , the experts have said. The will almost certainly fall in the sea or on an uninhabited piece of land.
During its mission, ROSAT operated at distances of up to 585 kilometres above Earth's surface, but it has lost since its decommissioning, and in June 2011 it was about 327 kilometres above the ground.
A controlled re-entry was not possible at the end of its mission in 1999 because the spacecraft does not have a on board, the officials said.
ROSAT was launched in June 1990 to allow researchers to perform an all-sky survey of X-ray sources with an imaging for the first time.
Last month, a bus-sized US satellite that hurtled unpredictably toward Earth crossed over Africa and the northern Atlantic before plunging into the Pacific Ocean off California, NASA said.
There were no sightings or reliable accounts of damage as the six-tonne Upper Atmosphere Research Satellite (UARS) fell from the sky.
(c) 2011 AFP
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