THE NEUTRON STAR, 2023. The Neutron Star coin, the third and final coin in The Uncharted Universe, shows how a massive star, combined with gravitational collapse, becomes one of the densest stellar objects in the universe (2023).
In the centre of The Neutron Star coin, a hemisphere curves inwards on one side and outwards on the other. Neutron stars are still something of a mystery, but this little masterpiece makes them a lot more tangible. Among the densest stellar objects in the universe, neutron stars are heavier than the Sun itself.
A superb representation of this unique galactic phenomenon, this little beauty weighs considerably less. Featuring a semi-sphere in its centre that curves inwards on one side and outwards on the other, the last coin in The Uncharted Universe series is designed to be a simplified representation of that unique galactic phenomenon – the neutron star. There are thought to be up to one billion neutron stars in the Milky Way.
This figure is obtained by estimating the number of stars that have undergone a supernova explosion, a spectacular explosion of a massive star. Combined with gravitational collapse, this creates a compact and super-dense object known as a neutron star. After black holes, neutron stars are the densest stellar objects in the universe.
Greece – 10 euro silver, MATHEMATICIANS – EUCLID, 2023
Euclid is considered the father of geometry. He lived in Alexandria during the reign of Ptolemy I and must have flourished about 300 BC. His central work was the Elements, where he presented the fundamental concepts and principles of geometry and, based on five indemonstrable postulates or axioms (e.g. two points determine one and only one straight line), managed to summarise the geometric wisdom of the time in a comprehensible and coherent system, named Euclidean geometry in his honour.
His influence was so immense that it was not until the 19th century that a non-Euclidean geometry was developed. He also wrote Optics, Catoptrics, Conics, etc. They say that when Ptolemy once asked him if there was in geometry any shorter way than that of the Elements, he replied that there was no royal road to geometry.
THE AUTOMATIC MAIDSERVANT OF PHILO. GREEK CULTURE – ANCIENT GREEK TECHNOLOGY
The automatic maidservant of Philo is described in the Pneumatics of Philo of Byzantium, a 3rd century BC engineer who lived in Alexandria. It is an automaton (robot) in the form of a (life-size) maidservant holding a wine jug in her right hand.
Inside the effigy were two tanks, one for wine and one for water (as the Greeks used to drink their wine diluted), and a mechanism consisting of liquid and air tubes. By placing a cup on the extended left hand of the maidservant, the mechanism started to work.
Air pressure pushed the liquids (first wine and then water) through the right arm into the jug and then into the cup, in the desired proportion. The automatic maidservant is the first known functional robot.
GREEK CULTURE – ANCIENT GREEK TECHNOLOGY – THE ANTIKYTHERA MECHANISM. The Antikythera mechanism was recovered from a shipwreck found in 1900 by sponge divers off the island of Antikythera.
Built in Hellenistic times, this intricate device was used for astronomical calculations and has been described as the oldest analogue computer. Its more than 30 bronze gearwheels rotated pointers over different dials. Thus, manually selecting a date on the main dial – which represented the zodiac, as well as the solar and lunar years – shifted the smaller gears, so that the pointers on the other dials indicated the position of the selected date in the four-year cycle of the Panhellenic games (Olympia, Pythia, Isthmia, Nemea), the positions of the five then-known planets and the correlation with astronomy cycles that were of particular interest to the ancient Greeks.
The mechanism also predicted solar and lunar eclipses. Research on the mechanism, which has fascinated scholars for decades, is still ongoing under the Antikythera Mechanism Research Project, which, using advanced imaging technologies, continues to provide impressive new insights into the mechanism’s complex inner workings.
George Gordon Byron (London 1788-Missolonghi 1824) was an emblematic figure of European Romanticism and one of the most important poets of the 19th century.
From a very young age, he embraced liberal and philhellenic ideals. His Grand Tour of the Mediterranean in 1809 brought him to Greece, to which he dedicated the second canto of his defining poetic work, Childe Harold’s Pilgrimage.
The outbreak of the Greek Revolution in 1821 set fire to Byron’s romantic soul. He ultimately moved to Greece in 1823 in order to take part in the struggle and settled in Missolonghi, where he spent much of his fortune on setting up military and naval units. However, he was never to see action, as his life was cut short on 19 April 1824, following a serious illness. His untimely death was a tragic loss and was deeply mourned by the Greeks, but at the same time boosted philhellenic sentiment around the world.
SILVER COLLECTOR COIN 10 EURO DEDICATED TO: “80 YEARS FROM THE BATTLE OF CRETE”. The Battle of Crete (20 May – 1 June 1941) was one of the most dramatic episodes of World War II. After occupying the rest of Greece, the Germans launched an unprecedented airborne operation on Crete, spearheaded by parachutists who were to seize the airfields so that ground troops could then be landed. The island was defended by Cretan civilians, the remnants of the Greek Army (without its Cretan Division, stranded on the mainland), as well as British, Australian and New Zealand allies. After suffering heavy losses on day one of the Battle,
the Germans seized the Maleme airfield on day two and thereafter occupied the entire island. The heroic resistance of the Cretan people won them worldwide admiration, but also led to harsh German reprisals.
The first coin of a collection consisting of three coins, the likes of which have never previously existed, The Uncharted Universe takes us to the deepest depths of the universe and gives us a fascinating glimpse of three physical-astronomical phenomena.The first coin of a collection consisting of three cointronomical phenomena. The S-shaped first coin in the series, The Milky Way, is curved in a similar way to our home galaxy. The story it tells about the cosmos also features surprising twists and turns. In 1920 Edwin Hubble showed that the Milky Way is just one among many galaxies. Although this made the earth seem increasingly insignificant, the smaller the planet felt, the greater our knowledge of outer space became and the more we began to understand our physical place in the cosmos.
Collector case of the 8 silver coins. The collection of the 8 silver coins is available in a wooden collector case with the corresponding certificates. The collection includes the following coins: 1830, The first Greek State. The coin depicts Theodoros Kolokotronis.
1864, The Ionian Islands (Heptanese). The coin depicts Ioannis Kapodistrias. 1881, Thessaly – Arta. The coin depicts Rigas Velestinlis (Feraios). 1913, Crete. The coin depicts Eleftherios Venizelos. 1913, Macedonia. The coin depicts Pavlos Melas.
1913, Epirus. The coin depicts Athanasios Tsakalof. 1920, Thrace. The coin depicts Georgios Vizyinos. 1947, The Dodecanese. The coin depicts the Lady of Ro.