ΒΑΡΥΤΗΤΑ ΚΑΙ ΕΠΙΤΑΧΥΝΣΗ

ΒΑΡΥΤΗΤΑ ΚΑΙ ΕΠΙΤΑΧΥΝΣΗ
Απευθύνεται σε μαθήτριες και μαθητές του Λυκείου,Πραγματεύεται τις κοινές διαπιστώσεις παρατηρητή όταν βρεθεί μέσα σε κινούμενο ανελκυστήρα ή μέσα σε βαρυτικό πεδίο. Παραγγελία στο email: gakon67(at)hotmail.com

ASTROPHYSICS - 天体物理学

                               KIP THORNE IN ATHENS AND THESSALONIKI.

O Kip Thorne έρχεται στην Αθήνα την Πέμπτη 23  Μαΐου 2019

Public talks by Kip Thorne in Athens and Thessaloniki


Our society co-organizes two public talks by Prof.  Kip Thorne  (Nobel Prize in Physics 2017) in Athens (May 23, 2019) and in Thessaloniki (May 24, 2019). All members of our society are cordially invited to these public outreach events! Full details (venue, time, distribution of free entrance tickets) regarding both talks can be found here. The two events are also organized as part of the 100 year centenary celebrations of the International Astronomical Union (IAU-100).



MAY 2019 BY NICK KYRIAZOPOULOS

Nice photo and video from NASA

Official NASA photographs from agency photographers chronicle what's making news across the agency, from launches and landings to important science announcements.

APRIL 2019 by Nick Kyriazopoulos



PHAROS: The multi-messenger physics and astrophysics of neutron stars




The recent discovery of gravitational waves will allow in the following years an unprecedented view of previously invisible parts of the Universe. This will unravel the physics of the most compact stars, the neutron stars, which are unique objects whose emission encompasses all the available multi-messenger tracers: electromagnetic waves, cosmic rays, neutrinos, and gravitational waves. These relativistic stars are also unique laboratories where not only the most extreme gravity and electromagnetism can be probed, but also the strong and weak interaction can be studied in regimes that have no hope of being explored on Earth. The study of these objects transcends the traditional astrophysical approach and requires a multidisciplinary effort that spans from particle and nuclear physics to astrophysics, from experiment to theory, from gravitational waves to the electromagnetic spectrum

FEBRUARY 2019 by Nick Kyriazopoulos 












GRAVITATIONIONAL WAVES


Einstein’s theory of General Relativity is perhaps the most elegant attempt by humankind to capture the laws of physics. Tested to exquisite precision in the weak-field regime, its unique geometric structure is manifest in strong field regions, especially around black holes. Decades of dedicated theoretical efforts were rewarded with an ornate mathematical theory of black holes and their perturbations, establishing the simplicity of black hole spacetimes. In parallel, breakthroughs on the numerical evolution of the Einstein field equations have taught us how black holes interact and merge, releasing huge amounts of gravitational-wave energy.


JANUARY 2019 by Nick Kyriazopoulos














CROSSWORD









                                     NICE PHOTO

                                      VOYAGER



                                           Galileo
                                 video in Greek





 INTERESTING LESSONS

free lessons



MUSIC IN SPACE







Meteorite in Russia





                                    video from sky fall




                                 SOUNDS FROM SPACE


                                                SOUNDS




                          Total Eclipse in Australia






NASA and NAXOS





Nasa is taking a photo of the sun from Naxos 





Have you ever dreamed of flying high above the Earth?












Transit of Venus 2012, the next one it will occur next century!!!

venus 




Image of the Venus transit across the sun's disk snapped by the Solar Dynamics Observatory on June 5, 2012, and shown in a NASA webcastit is a collecting image of one of the rarest predictable solar events: the transit of Venus across the face of the sun. This event happens in pairs eight years apart that are separated from each other by 105 or 121 years. The last transit was in 2004 and the next will not happen until 2117.

ROCKET COMPETITION




SOUNDS FROM SPACE

JUPITER- EARTH- MOON







Chios from space


Photo from space, which was taken from shuttelite Columbia in February 2003.





VOYAGER

VOYAGER


Microkosmos to the Universe



http://img.izismile.com/img/img5/20120213/flash/universe.swf




Europes Vega's Rocket

http://www.space.com/14550-photos-europe-vega-rocket-launch-debut-flight.html?utm_content=SPACEdotcom&utm_campaign=seo%2Bblitz&utm_source=twitter.com&utm_medium=social%2Bmedia



Strange things in space!

http://www.lifeslittlemysteries.com/1171-slideshow-strange-everyday-things-space.html


Cat without gravity

http://www.youtube.com/watch?v=JAWuMd6GOfs&feature=endscreen&NR=1

Moon - Surface
Moon through a telescope

MOON - TIDE

Tide is an oscilation. Its  frequence is ordered by the moon.
These are some interesting links from  Bay of Fundy, in Canada.


video1 : http://www.youtube.com/watch?v=EnDJ6_XpGfo&feature=endscreen&NR=1


video2:



video 3
http://www.youtube.com/watch?v=EXKJ7a0V2-4&NR=1&feature=endscreen


Telescope
Galilei-Newton








Students are visiting the Greek University of Athens
2011-2013

2012-2013

You can find more details at the link: http://observatory.phys.uoa.gr/ 


Lunar eclipse 10 Dec 2011


http://www.youtube.com/watch?v=iTIeUYKll2o


Comments from GREECE:
 Inredible site, we can see also and the mechanism of anikithira..very good...i do not like only the mention about the false landing in the moon!( student from Greece).
2012
http://www.youtube.com/watch?feature=endscreen&NR=1&v=fRK2GGJo36U

Interesting greek video





http://www.youtube.com/watch?v=kjuf-KizciE&NR=1&feature=endscreen

http://www.youtube.com/watch?v=NrYVC85v6zk&feature=endscreen&NR=1

ASTROBIOLOGY

Europa's "Great Lake." Researchers predict many more such lakes are scattered throughout the moon's icy shell. Credit: Britney Schmidt/Dead Pixel VFX/Univ. of Texas at Austin.



In a potentially significant finding in the search for life beyond Earth, scientists studying data from NASA’s Galileo probe have discovered what appears to be a body of liquid water the volume of the North American Great Lakes locked inside the icy shell of Jupiter’s moon Europa. The water could represent a potential habitat for life, and many more such lakes might exist throughout the shallow regions of Europa’s shell, say researchers writing in the journal Nature. NASA’s press conference can be viewed here.









The Van Allen radiation belts,


shown here in cross section roughly to scale, wrap around Earth above the atmosphere with axial symmetry about the geomagnetic axis. The inner belt is characterized by its trapped population of sub-GeV protons. The magnetic axis is tilted 10° from the rotation axis and the center of the dipole field is offset from the planet’s center by 560 km. As a result, the inner belt comes closest to Earth’s surface between South America and South Africa, creating the so-called South Atlantic Anomaly. That’s the only region where the PAMELA spectrometer, orbiting with a maximum altitude of 600 km, can access the inner belt in its search for trapped antiprotons.




The asteroid Itokawa photographed from a spacecraft Hayabusa.





More details you can find at the URL:  Physics Today


What is happening at the surface of the sun?

http://www.youtube.com/watch?v=mJCOqjG4ap8


Mετεωριτης απειλεί την Γή!!!

Ο αστεροειδής 1999 RQ36 έχει διάμετρο περίπου 560 μέτρων και αρκετές μελέτες τον τοποθετούν ανάμεσα στους επικίνδυνους για τη Γη αστεροειδείς, με πιθανές οκτώ ημερομηνίες σύγκρουσης με τον πλανήτη μας μεταξύ 2169 και 2199!
http://www.telescopeshop.gr/news_show.asp?articleId=347

Sutellite is crashing...



Just remember, 'not UARS — or rather, yours — to keep,'" said space artifacts expert Robert Pearlman, editor of the website collectSPACE.com and a frequent SPACE.com contributor. "Should the public come across debris they believe to be from the downed satellite, they should alert the authorities, or the authorities may come after them."









«Ο Αστροναύτης της NASA Dr. James Newman συνομιλεί με το κοινό σε μια μοναδική συνάντηση στο Ίδρυμα Ευγενίδου»







Mια μοναδική συνάντηση-συζήτηση του Αστροναύτη της NASA Dr. James Newman με το ελληνικό κοινό διοργανώνει το Ίδρυμα Ευγενίδου τη Δευτέρα 19 Σεπτεμβρίου 2011 και ώρα 19.30.






Μηχανισμός των Αντικυθήρων

Antikythera exhibition in Paris






We are delighted to announce that the "Antikythera Mechanism" exhibition has moved to Paris, at the Musée des Arts et Métiers. A model of the Antikythera Mechanism, built by the Aristotle University in Greece, together with 17th and 18th centuries astronomical clocks, and the modern mechanism of a watch inspired by the Antikythera Mechanism and designed by Hublot, will be on display. A film in 3D created by the Swiss film-maker Philippe Nicolet will narrate the story of the Antikythera Mechanism. A 2D version of this film can be watched here:



http://www.youtube.com/watch?v=UpLcnAIpVRA



The History, Philosophy and Didactics of Science and Technology Programme

Ο μηχανισμος  Αντικυθηρων με Lego

Comments from a Greek student: Amazing, how can the Ancient Greek Philosophers managed it?



Τέλος εποχής - NASA- Last mission.





 Our home galaxy, the Milky Way!

Nepalese Night


Photograph by Anton Jankovoy, My Shot



A river of stars flows over the Mardi Khola Valley in the Himalaya, as seen in a recently submitted long-exposure picture taken in Nepal. The dense stellar band is the plane of our home galaxy, the Milky Way. (See a prize-winning picture of the Milky Way over Crater Lake in Oregon.)



Published August 4, 2011



Νερό στο εσωτερικό της Σελήνης.
(Water under the surface of moon.)
Το εσωτερικό της Σελήνης περιέχει όσο νερό διαθέτει και η Γη, σύμφωνα με έρευνα που δημοσιεύθηκε την Πέμπτη και η οποία θέτει υπό αμφισβήτηση τη θεωρία της δημιουργίας του φυσικού δορυφόρου της Γης. Αυτή η ανακάλυψη δείχνει ακόμη ότι η Σελήνη περιέχει εκατό φορές περισσότερο νερό από ό,τι πιστευόταν μέχρι σήμερα. Οι συγγραφείς της μελέτης κατέληξαν σε αυτά τα συμπεράσματα, αφού εντόπισαν μόρια νερού και άλλα πτητικά στοιχεία σε ποσότητα μάγματος που είχαν φέρει οι αστροναύτες του Apollo 17, στην τελευταία αποστολή στο φεγγάρι τον Δεκέμβριο του 1972. Αυτά τα δείγματα του μάγματος (που εκτινάχθηκαν από μεγάλα βάθη από τη σεληνιακή ηφαιστειακή δραστηριότητα πριν από αρκετά δισεκατομμύρια χρόνια) είναι το καλύτερο μέσο που έχουμε στη διάθεσή μας για να εκτιμήσουμε την ποσότητα του νερού στο εσωτερικό της Σελήνης, δήλωσε ο Τζέιμς Βαν Ορμαν, καθηγητής γεωλογίας. «Το εσωτερικό της Σελήνης φαίνεται να είναι αρκετά παρόμοιο με το εσωτερικό της Γης ως προς αυτά που γνωρίζουμε για την αφθονία του νερού», προσθέτει, στη μελέτη που δημοσιεύθηκε στο Science Express, στην διαδικτυακή έκδοση του αμερικανικού επιστημονικού περιοδικού Science ( Καθημερινή, 29/5/11)





First landing at the moon










Πρώτη καταγραφή αντιύλης στη Γη.







(Antimatter Found Orbiting Earth—A First)








Εκτός από τη δημιουργία αντιπρωτονίων στα επιστημονικά εργαστήρια, για πρώτη φορά καταγράφηκαν στο νότιο σέλας.




The antiprotons were discovered in a particular region of the Van Allen belt called the South Atlantic Anomaly, where the inner ring of the belt dips closest to Earth's surface.




Antiprotons likely exist in other parts of the Van Allen Belt as well, but they are orbiting at altitudes too high for PAMELA to detect, the scientists say


Χρήσιμες πληροφορίες θα βρείτε στο παρακάτω site.

I)The assumptions of the Greek Pythagorean
philosopher Philolaos,for the universe and
II) how they were treated by subsequent philosophers and scientists.



THE MUSIC WE CANNOT HEAR.



The sky was the first part of the world which was subjected to mathematical examination, (Wertheim, 1998, 17).






The properties and proportions of musical harmonies are related to numbers, and since all things seemed to equate nature with numbers, even though numbers were the key to all of nature, it was resulted that the data of numbers were elements of all beings, and that the whole sky was harmony and number.






"According to the Pythagoreans, the sky is a number, because the speeds of the planets and their distances from the center are geometric ratios. The slower and faster moving planets are in a ratio and they produce the corresponding musical harmony "(Kalfas, 2009, 265).


This is the music of the stars which was listening by Pythagoras, as the son of Apollo and Pythais.


Specifically they experimented with the sound which was produced, when they changed the length, the tension and the thickness of the string. They found that if you double the length of a string produces the same note but an octave lower in and is in harmony with the note that gave the original length, (Wertheim, 1998, 54). . The change in length in an inappropriate fraction lead to disharmony, (Simon Singh, 2005). So Pythagoras produced harmonious musical notes by varying the content of water in a cup and beating the cup each time, (Marcus Du Sauty, 2005, 124).






Philolaos managed to extract specific musical intervals. For this reason, the well-tuned guitar is aesthetic value corresponding to a mathematical instrument, (Burkert, Walter, 1972).


He argued that the motion of the sun, the moon, and the planets in the sky create specific musical notes, which were determined by the length of the orbit. Under this assumption we are immersed in the heavenly music, but we cannot understand it because we hear it since we were born and we were used to it.






Moreover, in every region of the sky there is an inherent human physical condition, since each geometric shape in the sky can be corresponded to a number and its passion. This numerical universe was combined with the moral characteristics of numbers. As ratios are behind the harmony of sounds, they could imagine harmony behind the dance of the planets and also they accepted the divine cosmic music. When the soul could hear the cosmic music is released from the material dimension of the body.


Also those elements of numbers and harmonies which were able to show that they are a reflection of the properties and parts of the sky and the whole cosmic order, those are collected and joined together, (Kalfas.2009, 165)


The belief of the Pythagoreans for the numbers were so strong, that they believed : there are ten stars that roam the sky, although there were visible only nine, the tenth planet was adding and was called anti-earth.




The nine celestial bodies revolved around the central fire was Earth, the seven planets known in antiquity (Sun, Moon, Mercury, Venus, Mars, Jupiter, Saturn) and the sphere of the fixed stars. (Kalfas, 2009.266 ). This non-geocentric system orbiting around a central point, from which was taken power and was the driving force behind the whole universe. The noblest element held polite place, so the fire must be at the center where it could precaution in "prisons’ Zeus." As the associate of Aristotle, Theophrastus's secular system differs in Olympus, in Cosmos and in Iposelinia ( under moon) and perigee region ( above earth) where the changes occur and called Uranus (Heaven), (Carl Huffman, 1993).

ANTICHTHON



The Antichthon was a star, which was moving diametrical to the Earth and it was not visible from Earth and it was complement the sum of the temple 10 of the first four numbers 4 +3+ 2+ 1. Each one of these numbers is identified with a concept or entity, such as the number 4 with the judiciary and the number 1 with the soul. It was invisible to us because the people inhabit in the opposite t hemisphere of the earth.

This individual case was reported for Philolaos from Aristotle in his book On Heaven (XIII, 293a, 18). 'Thus, the original invention by Philolaos created a rift in scientific thought at the time.


The ancient Greek statement was:

Kαὶ ὁ Ἀρχιμήδης ταύτης τῆς δόξης γέγονε (II, 13, 229β). Ἐν μὲν τῷ μέσῳ τοῦ παντὸς πῦρ εἶναί φασι, περὶ δὲ τὸ μέσον τὴν ἀντίχθονα φέρεσθαί φασι γῆν οὖσαν καὶ αὐτὴν ἀντίχθονα δὲ καλουμένην διὰ τὸ ἐξ ἐναντίας τῇδε τῇ Γῇ εἶναι, μετὰ δὲ τὴν ἀντίχθονα ἡ γῆ ἣδε φερομένη καὶ αὐτὴ περὶ τὸ μέσον, μετὰ δὲ τὴν γῆν ἡ σελήνη... τὴν δὲ γῆν ὡς ἓν τῶν ἂστρων οὖσαν κινουμένην περὶ τὸ μέσον κατὰ τὴν πρὸς τὸν ἣλιον σχέσιν νύκτα καὶ ἡμέραν ποιεῖν... ἡμέραν μὲν γὰρ ποιεῖ τὸ πρὸς τῷ ἡλίῳ μέρος καταλαμπομένη... οἱ δὲ γνησιώτερον αὐτῶν μετα-σχόντες πῦρ μὲν ἐν τῷ μέσῳ λέγουσι τὴν δημιουργικὴν δύναμιν τὴν ἐκ μέσου πάσαν τὴν γῆν ζῳογονοῦσαν καὶ τὸ ἀπεψυγμένον αὐτῆς ἀναθαλποῦσαν.
Symplikios refered that Antichthon follows a circular motion around the central fire, and it was not moving far away from earth.

«Επομένη τη γη ταύτη»

In fact the earth turns the uninhabited part towards Antichthon, so it was never seen by humans. The enigmatic element of the global standard for that time was not the moving earth, but the existence of antichthonos. The philosophers were concerned about the role and purpose of the introduction of an unseen planet in the planetary system. They did not surprised about the moving earth, which they testified that it existed as a legal and acceptable idea in certain communities of people before Filolaou. Otherwise the philosophers would be surprised and would face surprisingly the non-geostationary this global model (Carl Huffman, 1993).