The Arch of Constantine (Italian: Arco di Costantino) is a triumphal arch in Rome dedicated to the emperor Constantine the Great. The arch was commissioned by the Roman Senate to commemorate Constantine's victory over Maxentius at the Battle of Milvian Bridge in AD 312. Situated between the Colosseum and the Palatine Hill, the arch spans the Via Triumphalis, the route taken by victorious military leaders when they entered the city in a triumphal procession. [a] Dedicated in 315, it is the largest Roman triumphal arch, with overall dimensions of 21 m (69 ft) high, 25.9 m (85 ft) wide and 7.4 m (24 ft) deep.[1] It has three bays, the central one being 11.5 m (38 ft) high and 6.5 m (21 ft) wide and the laterals 7.4 m (24 ft) by 3.4 m (11 ft) each. The arch is constructed of brick-faced concrete covered in marble.
The three bay design with detached columns was first used for the Arch of Septimius Severus in the Roman Forum (which stands at the end of the triumph route) and repeated in several other arches now lost.
Though dedicated to Constantine, much of the sculptural decoration consists of reliefs and statues removed from earlier triumphal monuments dedicated to Trajan (98–117), Hadrian (117–138) and Marcus Aurelius (161–180), with the portrait heads replaced with his own.[2]
The arch, which was constructed between 312 and 315, was dedicated by the Senate to commemorate ten years (a decennia[b]) of Constantine's reign (306–337) and his victory over the then reigning emperor Maxentius (306–312) at the Battle of Milvian Bridge on 28 October 312,[4] as described on its attic inscription,[5] and officially opened on 25 July 315. Not only did the Roman senate give the arch for Constantine's victory, they also were celebrating decennalia: a series of games that happened every decade during the Roman Empire. On these occasions they also said many prayers and renewed both spiritual and mundane vows.[6] However, Constantine had actually entered Rome on 29 October 312, amidst great rejoicing, and the Senate then commissioned the monument.[7] Constantine then left Rome within two months and did not return until 326.[8]
During the Middle Ages, the Arch of Constantine was incorporated into one of the family strongholds of ancient Rome, as shown in the painting by Herman van Swanevelt, here. Works of restoration were first carried out in the 18th century,[11][c] the last excavations have taken place in the late 1990s, just before the Great Jubilee of 2000. The arch served as the finish line for the marathon athletic event for the 1960 Summer Olympics.
In the lead-up to the launch of the James Webb telescope, we look at the scientific objectives of the most powerful space observatory ever sent into orbit.
Are we alone in the universe? What did the first galaxies formed after the Big Bang look like? How did the planets in our solar system emerge? The James Webb telescope hopes to find answers to these existential questions.
Set to launch on December 22, the James Webb is the product of the combined scientific prowess of NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA) – and by extension, Université de Montréal (UdeM). The CSA contributed a scientific instrument and a guidance sensor to the massive observatory and René Doyon, Director of UdeM’s Institute for Research on Exoplanets (iREx) and a professor in the Physics Department, is the principal investigator on the Canadian scientific team.
Together, the components supplied by the CSA, NASA and the ESA form the most complex, accurate and powerful space observatory ever built, one that promises revolutionary discoveries in astronomy.
The unparalleled power of the observatory will help scientists throughout the world scrutinize the distant reaches of the universe to learn more about the composition and inhabitability of exoplanets and study the life cycle of stars.
Exploring new worlds in search of life
The James Webb Telescope is the successor to the Hubble space telescope but is more precise and efficient because of the size of its mirror, the range of light it can detect and its location.
These attributes will enable the Webb to study the planets in our solar system and other planetary systems in unprecedented detail. Moreover, the scientific instrument developed by Doyon’s team is designed to analyze many types of celestial bodies, including the atmospheric composition of distant exoplanets.
“What we’re looking for, our holy grail, are ‘biosignatures,’ that is, signs of extraterrestrial life,” explained iREx coordinator Nathalie Ouellette, an astrophysicist who does communications for the James Webb.
She hastened to add that we shouldn’t imagine these signs of life the way they are depicted in science fiction films: “We’re talking about finding signs of biological activity or the signature of certain molecules that we have identified as essential to life, such as oxygen, water vapour, carbon dioxide, methane and ozone. Based on the presence of such molecules, particularly in certain combinations, we may be able to determine that conditions are conducive to the development of life when we explore an exoplanet using the telescope.”
Casting light on the dawn of the universe
Telescopes are also time machines of a sort. “Looking into space is like looking into the past,” said Ouellette. “Light waves travel so fast that, to the naked eye, they seem to flash instantly from one point to another. In space, however, the distances are so vast that the time it takes light to travel is perceptible.”
That makes the Webb a marvellous time machine. It will be able to see back in time to 200 million years after the Big Bang, something that has never been done before. “With the Hubble, we could go to 500 million years after the Big Bang, so now we’re going 300 million years further,” noted Ouellette. “That’s remarkable, considering that the beginning of the universe was a tumultuous period. Galaxies were colliding and stars were forming at a rapid pace.”
“Tell me where you come from and I’ll tell you who you are”
The Webb will thus improve our understanding of the development of the first luminous objects (galaxies) over time. Ouellette believes the telescope will also provide insight into the creation of our own solar system.
“We still have many questions about the origins of life in our solar system. We don’t know exactly how we came to be on Earth and how the planets were formed,” Ouellette pointed out. “By studying other systems, stars and planets at various stages of development, we hope to be able to trace our own history and understand ourselves better.”
That is the ultimate goal of the James Webb: to revolutionize our understanding of the universe and, above all, to place the Earth, in all its fragility and uniqueness, in a broader context.
Si amas la cultura, la tradición, las aventuras extremas y planeas pasar unas vacaciones inolvidables, te invitamos a celebrar el Año Nuevo Maya en la Riviera. Pero, si piensas que tendrás que esperar a que finalice el año, tenemos buenas noticias para ti: esta celebración milenaria ocurre en julio y no tendrás que esperar tanto, al contrario de la celebración mundial de Finde Año. A continuación, te contaremos la historia y orígenes de esta tradición y por qué no puedes dejar de vivirla. ¿Estás listo?
¿Año nuevo en Julio?
Es bien conocido que la cultura maya era ávida conocedora de la astronomía y de manera muy disciplinada seguían el movimiento de los astros para calendarizar y tipificar la importancia de los eventos que ocurrían en la tierra, en total sincronía con lo que ocurría en el cielo.
De acuerdo con el calendario maya “Haab” que sigue puntualmente el ciclo de la tierra en relación al sol, los astrónomos mayas determinaron que para ellos, el ciclo del año no iniciaba en enero, a diferencia del calendario gregoriano que rige nuestros ciclos y que heredamos de la cultura romana; los mayas medían el tiempo calculando hasta 18 ciclos vinculados por los movimientos de las principales luminarias de nuestro sistema (Luna y Sol), así como por los tránsitos planetarios de Venus y la ubicación de constelaciones como las Pléyades.
De acuerdo a este cálculo, el 26 de julio de cada año, daba inicio a un nuevo ciclo y a una nueva personalidad que caracterizaba al nuevo año y que era identificado con su propio glifo.
Pero, aunque el 26 es un día súper especial para esta ancestral cultura, el día 25 (El Día Fuera Del Tiempo) era incluso más importante porque en esta fecha los mayas acostumbraban a dar las gracias y tomarse un tiempo para reflexionar sobre las ganancias, logros y sobre todo, las lecciones que se aprendieron a los largo del ciclo anterior.