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

A Falling satellite ...[ 2508 ]

Falling satellite enters Earth's atmosphere

THE INTERDEPENDENT Sunday, 23 October 2011
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This undated artist rendering provided by EADS Astrium shows the satellite ROSAT.
AP
This undated artist rendering provided by EADS Astrium shows the satellite ROSAT.


A defunct satellite entered the atmosphere early Sunday and pieces of it were expected to crash into the earth, the German Aerospace Center said. 
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There was no immediate solid evidence to determine above which continent or country the ROSAT scientific research satellite entered the atmosphere, agency spokesman Andreas Schuetz said.
Most parts of the minivan-sized satellite were expected to burn up during re-entry, but up to 30 fragments weighing 1.87 tonnes (1.7 metric tonnes) could crash into Earth at speeds up to 280 mph (450 kph). 
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Scientists were no longer able to communicate with the dead satellite and it must have traveled about 12,500 miles (20,000 kilometers) in the last 30 minutes before entering the atmosphere, Schuetz said.
Experts were waiting for "observations from around the world," he added.
Scientists said hours before the re-entry into the atmosphere that the satellite was not expected to hit over Europe, Africa or Australia. According to a precalculated path it could have been above Asia, possibly China, at the time of its re-entry, but Schuetz said he could not confirm whether the satellite actually entered above that area. 
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The 2.69-tonne (2.4 metric tonne) scientific ROSAT satellite was launched in 1990 and retired in 1999 after being used for research on black holes and neutron stars and performing the first all-sky survey of X-ray sources with an imaging telescope.
The largest single fragment of ROSAT that could hit into the earth is the telescope's heat-resistant mirror. 
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During its mission, the satellite orbited about 370 miles (600 kilometres) above the Earth's surface, but since its decommissioning it has lost altitude, circling at a distance of only 205 miles (330 kilometres) above ground in June for example, the agency said.
Even in the last days, the satellite still circled the planet every 90 minutes, making it hard to predict where on Earth it would eventually come down.
A dead NASA satellite fell into the southern Pacific Ocean last month, causing no damage, despite fears it would hit a populated area and cause damage or kill people.
Experts believe about two dozen metal pieces from the bus-sized satellite fell over a 500-mile (800 kilometer) span of uninhabited portion of the world. 
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The NASA climate research satellite entered Earth's atmosphere generally above American Samoa. But falling debris as it broke apart did not start hitting the water for another 300 miles (480 kilometres) to the northeast, southwest of Christmas Island.
Earlier, scientists had said it was possible some pieces could have reached northwestern Canada.
The German space agency puts the odds of somebody somewhere on Earth being hurt by its satellite at 1 in 2,000 - a slightly higher level of risk than was calculated for the NASA satellite. But any one individual's odds of being struck are 1-in-14 trillion, given there are 7 billion people on the planet.
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