  KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS  
  Auteur  Message 

yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 24 Fév à 9:33  
 Sa fête sera désormais le 7 Novembre...
Nous n'avons pas d'information concernant la journée de fête associée au prénom Kira.
Pour une jeune femme de Lettonie par nuages570.
SES ORIGINES, SA LIBERTÉ DE CULTE, SES PHILOSOPHIES ET SES ESPOIRS.
The force that protects our planet.
Nom : Kira
Sexe : Mixte (Masculin et Féminin)
Utilisation : Kira, d'origine gaéliqueécossais, est un prénom très populaire pouvant être porté par une personne de sexe masculin et féminin.
Les personnes ayant le prénom Kira peuvent être originaires de : Allemagne, Autriche, Azerbaïdjan, Biélorussie, Bulgarie, ÉtatsUnis d'Amérique, Irlande, Japon, Kazakhstan, RoyaumeUni, Russie, Suisse, Ukraine.
Variantes: Les variantes du prénom Kira à travers le monde sont Ciara.
Signification : Sombre (Dark), Dame noire (Dark lady) (*) .
Le Nombre actif qui correspond à ce prénom est 3.
Interprétation : Qualités: Créatif, Joyeux Planète dominante: Jupiter Couleurs: Pourpre, Lilas, Mauve Pierres précieuses: Améthyste
Sa fête sera désormais le 7 Novembre...
Citations du Citoyen Tignard Yanis.
COMPTE VK DE TIGNARD YANIS
UN JOUR POUR PROFITER DES ACTES. JE PARLE DE LA CHANCE. CELLE QUI PORTE UNE ORAISON VERS LA FLORAISON. POÉSIE DU CITOYEN TIGNARD YANIS ALIAS TAY La chouette effraie.
LE DESTIN ET LA VIE: LE COEUR D'UN CONCEPT S'EST EN IGNORÉ LA FIN LORSQUE L'ON S'APERÇOIT QU'UN NOUVEL HORIZON SE PROFIL DEPUIS LE DÉPART DE LA PALPITATION. POÉSIE DU CITOYEN TIGNARD YANIS
La circonstance est une affirmation de la conviction car elle implique une conscience sur l'événement. L'évolution est une évolution car elle implique une évidence d'esprit et d'expression. Philosophie poétique du Citoyen Tignard Yanis.
LE TERME DE SIGNALER CORRESPOND AUX CIRCONSTANCES DU TEMPS. AINSI LA MANIÈRE DÉFINIE LE TERME ET LE TERRITOIRE EST LA CORRESPONDANCE DE LA CIRCONSTANCE. CITATION DU CITOYEN TIGNARD YANIS.
SENTIMENTS DE TAY La chouette effraie.
22 February 2018
With the aim of making the best possible use of existing satellites, ESA and Canada have made a deal that turns Swarm into a foursatellite mission to shed even more light on space weather and features such as the aurora borealis.
In orbit since 2013, ESA’s three identical Swarm satellites have been returning a wealth of information about how our magnetic field is generated and how it protects us from dangerous electrically charged atomic particles in the solar wind.
Canada’s Cassiope satellite carries three instrument packages, one of which is ePOP. It delivers information on space weather which complements that provided by Swarm. Therefore, the mission teams began looking into how they could work together to make the most of the two missions.
To make life easier, it also just so happens that Cassiope’s orbit is ideal to improve Swarm’s readings.
And now, thanks to this international cooperation and formalised through ESA’s Third Party Mission programme, ePOP has effectively become a fourth element of the Swarm mission. It joins Swarm’s Alpha, Bravo and Charlie satellites as Echo. Cassiope carries ePOP
Josef Aschbacher, ESA’s Director of Earth Observation Programmes, noted, “This is a textbook example of how virtual constellations and collaborative initiatives can be realised, even deep into the missions’ exploitation phases.
“We embrace the opportunity to include ePOP in the Swarm mission, especially because it is clear that the more data we get, the better the picture we have of complex space weather dynamics.
“ESA is looking forward to seeing the fruits of this collaboration and the improved return on investment for both Europe and Canada.”
Andrew Yau from the University of Calgary added, “Swarm and ePOP have several unique measurement capabilities that are highly complementary.
“By integrating ePOP into the Swarm constellation, the international scientific community will be able to pursue a host of new scientific investigations into magnetosphere–ionosphere coupling, including Earth’s magnetic field and related current systems, upperatmospheric dynamics and aurora dynamics.” Birkeland currents
John Manuel from the Canadian Space Agency noted, “We are pleased to see ePOP join ESA’s three Swarm satellites in their quest to unravel the mysteries of Earth's magnetic field.
“Together, they will further improve our understanding of Earth's magnetic field and role it plays in shielding Canada and the world from the effects of space weather.”
Giuseppe Ottavianelli, ThirdParty Mission Manager at ESA concluded, “I am pleased that the ePOP ensemble is now formally integrated into our Swarm constellation.
“This milestone achievement confirms the essential role of ESA’s Earthnet programme, enabling synergies across missions, fostering international cooperation, and supporting data access.”
While ePOP changes its name to Echo as part of the Swarm mission, it will also continue to provide information for its original science investigations.
http://www.esa.int/Our_Activities/Observing_the_Earth/Swarm/Swarm_trio_becomes_a_quartet
The force that protects our planet
SENTIMENTS DE TAY La chouette effraie ET RAPPORT DE Y'BECCA
Dernière édition par yanis la chouette le Sam 24 Fév à 9:46, édité 1 fois  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 24 Fév à 9:33  
 LE SYSTEME SOLAIRE ET LE COUPLE. Axel Bauer, Zazie  A Ma Place... https://www.youtube.com/watch?v=vOznRtE4fOg
The horizon or skyline is the apparent line that separates earth from sky, the line that divides all visible directions into two categories: those that intersect the Earth's surface, and those that do not. At many locations, the true horizon is obscured by trees, buildings, mountains, etc., and the resulting intersection of earth and sky is called the visible horizon. When looking at a sea from a shore, the part of the sea closest to the horizon is called the offing.[1] The word horizon derives from the Greek "ὁρίζων κύκλος" horizōn kyklos, "separating circle",[2] from the verb ὁρίζω horizō, "to divide", "to separate",[3] and that from "ὅρος" (oros), "boundary, landmark".[4]
Dans peu de temps, quelque deux ou trois cents ans, on considérera notre vie actuelle avec terreur et dérision, tout ce qui existe aujourd'hui paraîtra maladroit, lourd, très inconfortable, et étrange.
Oncle Vania (18991900) de Anton Pavlovitch Tchekhov

La dérision est peutêtre un rempart contre la solitude. En effet, les moqueurs veulent un public, et celui qui en est la victime est toujours seul.
Soudain dans la forêt profonde (2005) de Amos Klausner, dit Amos Oz

Le méchant redoute les hommes, il ne redoute pas le ciel ; le juste est tourné en dérision par les hommes, le Ciel n'agit pas ainsi envers lui.
Proverbe de Proverbes chinois

Ce qui sauve ces gens, c'est leur instinct de résistance, cette once de dérision, presque de gaieté, avec lesquels ils font mine d'ignorer leurs pertes. Ils rient peutêtre jaune, mais ils rient.
Journal de l'année du désastre (2012) de Kathrine Kressmann Taylor

Finalement, il n'y a jamais qu'un combat : celui des esprits sérieux contre les esprits ludiques, le grand Combat du Sens contre la Dérision nihiliste.
Topologie du pessimisme (1997) de Roland Jaccard

La Dérision est la Joie, née de ce que nous nous imaginons qu'il existe quelque chose que nous méprisons dans un objet que nous haïssons.
L'Ethique (1677), Livre III de Baruch Spinoza

Dire qu'hors de l'amour il n'y a rien, c'est frapper de dérision l'ambition individuelle et collective, qui mérite cette dérision, mais fautil le dire ? Certaines vérités sont cruelles. Les proclamer, c'est risquer de désespérer.
Journal de Jacques, comte de BourbonBusset

L'Egyptien naît avec un papyrus dans le coeur, où il est écrit en lettres d'or que la dérision sauve du désespoir.
L'Egyptienne (1991) de Gilbert Sinoué

Le rire, la moquerie, la dérision sont des entreprises de purification, de déblaiement, ils préparent des salubrités futures.
La nuit sera calme (1974) de Roman Kacew, dit Romain Gary

Quand nous approchons de l'heure de notre mort, notre vie familière peut paraître inchangée, l'audelà hurle à nos oreilles un chant profond qui tourne en dérision toutes nos petites préoccupations.
Gilles et Jeanne (1983) de Michel Tournier

Moi j'ai tout donné mes illusions Et ma vie et mes hontes Pour vous épargner la dérision De n'être au bout du compte Que ce qu'à la fin nous aurons été.
Le Roman inachevé (1956) de Louis Aragon

Ma joie serait grande de le pouvoir nommer fripon, fripouille, canaille, crapule, voyou, filou, jolis noms chargés d'évoquer ce que par dérision vous appelez un joli monde.
Journal du Voleur (1949) de Jean Genet

Le ton dominant de l'institution était la dérision de toute sensiblerie et l'exaltation des plus rudes vertus.
Fermina Marquez (1911) de Valéry Larbaud

Ainsi, l'avachissement d'une immense dérision envahitil le coeur sans plus d'angoisse, librement.
L'Erotisme (1957) de Georges Bataille

Je hais les mouches, leur vol est une aberration, une dérision du vol  à quoi bon voler, d'ailleurs, quand on sait marcher au plafond?
Eric ChevillardLe vaillant petit tailleur (2004) de Eric Chevillard

La dérision en toutes choses est l'ultime défi au malheur.
de JeanBaptiste Rossi, dit Sébastien Japrisot

Et qu'estce que la gloire? Un vain son répété,  Une dérision de notre vanité,  Un nom qui retentit sur des lèvres mortelles,  Vain, trompeur, inconstant, périssable comme elles.
Harmonies poétiques et religieuses, Pourquoi mon âme estelle triste? de Alphonse de Lamartine

C'est quelqu'un dont j'admirais l'étendue du talent en tant qu'homme de radio, acteur, cinéaste et chansonnier. Il y avait dans toutes ses activités une sorte d'unité, un ton nouveau, corrosif, de dérision et d'autodérision.
Réactions à la mort de Jean Yanne, le 23 mai 2003. de Gilles Jacob

Chantant des broquards et atteintes de mocquerie, par grande derision, sur la couardise et lascheté effeminée de Crassus.
Crassus, 60 de Jacques Amyot

Ainsi quand nous approchons de l'heure de notre mort, notre vie familière peut paraître inchangée, l'audelà hurle à nos oreilles un chant profond qui tourne en dérision toutes nos petites préoccupations.
Gilles & Jeanne de Michel Tournier

Details Open/Close
Title Earth from Space: Bering Strait Released: 23/02/2018 Length 00:02:26 Language English Footage Type Documentary Copyright ESA  European Space Agency Description
Earth from Space is presented by Kelsea BrennanWessels from the ESA Web TV virtual studios. Offering radar vision, Sentinel1 takes us over the Bering Strait in this edition, where the sea ice is particularly low this winter.
See also Earth from Space: Bering Strait to download the image.
https://www.esa.int/spaceinvideos/Videos/2018/02/Earth_from_Space_Bering_Strait
News  February 22, 2018 Seven Ways Mars InSight is Different
NASA's Mars InSight lander team is preparing to ship the spacecraft from Lockheed Martin Space in Denver, where it was built and tested, to Vandenberg Air Force Base in California, where it will become the first interplanetary mission to launch from the West Coast. The project is led by NASA's Jet Propulsion Laboratory in Pasadena, California.
We know what "The Red Planet" looks like from the outside  but what's going on under the surface of Mars? Find out more in the 60second video from NASA's Jet Propulsion Laboratory.
NASA has a long and successful track record at Mars. Since 1965, it has flown by, orbited, landed and roved across the surface of the Red Planet. What can InSight  planned for launch in May  do that hasn't been done before?
InSight is the first mission to study the deep interior of Mars.
A dictionary definition of "insight" is to see the inner nature of something. InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) will do just that. InSight will take the "vital signs" of Mars: its pulse (seismology), temperature (heat flow), and its reflexes (radio science). It will be the first thorough checkup since the planet formed 4.5 billion years ago.
InSight will teach us about planets like our own.
InSight's team hopes that by studying the deep interior of Mars, we can learn how other rocky planets form. Earth and Mars were molded from the same primordial stuff more than 4 billion years ago, but then became quite different. Why didn't they share the same fate?
When it comes to rocky planets, we've only studied one in great detail: Earth. By comparing Earth's interior to that of Mars, InSight's team hopes to better understand our solar system. What they learn might even aid the search for Earthlike exoplanets, narrowing down which ones might be able to support life. So while InSight is a Mars mission, it's also more than a Mars mission.
InSight will try to detect marsquakes for the first time.
One key way InSight will peer into the Martian interior is by studying motion underground  what we know as marsquakes. NASA has not attempted to do this kind of science since the Viking mission. Both Viking landers had their seismometers on top of the spacecraft, where they produced noisy data. InSight's seismometer will be placed directly on the Martian surface, which will provide much cleaner data.
Scientists have seen a lot of evidence suggesting Mars has quakes. But unlike quakes on Earth, which are mostly caused by tectonic plates moving around, marsquakes would be caused by other types of tectonic activity, such as volcanism and cracks forming in the planet's crust. In addition, meteor impacts can create seismic waves, which InSight will try to detect.
Each marsquake would be like a flashbulb that illuminates the structure of the planet's interior. By studying how seismic waves pass through the different layers of the planet (the crust, mantle and core), scientists can deduce the depths of these layers and what they're made of. In this way, seismology is like taking an Xray of the interior of Mars.
Scientists think it's likely they'll see between a dozen and a hundred marsquakes over the course of two Earth years. The quakes are likely to be no bigger than a 6.0 on the Richter scale, which would be plenty of energy for revealing secrets about the planet's interior.
First interplanetary launch from the West Coast
All of NASA's interplanetary launches to date have been from Florida, in part because the physics of launching off the East Coast are better for journeys to other planets. But InSight will break the mold by launching from Vandenberg Air Force Base in California. It will be the first launch to another planet from the West Coast.
InSight will ride on top of a powerful Atlas V 401 rocket, which allows for a planetary trajectory to Mars from either coast. Vandenberg was ultimately chosen because it had more availability during InSight's launch period.
A whole new region will get to see an interplanetary launch when InSight rockets into the sky. In a clear, predawn sky, the launch may be visible in California from Santa Maria to San Diego.
First interplanetary CubeSat
The rocket that will loft InSight beyond Earth will also launch a separate NASA technology experiment: two minispacecraft called Mars Cube One, or MarCO. These briefcasesized CubeSats will fly on their own path to Mars behind InSight.
Their objective is to relay back InSight data as it enters the Martian atmosphere and lands. It will be a first test of miniaturized CubeSat technology at another planet, which researchers hope can offer new capabilities to future missions.
If successful, the MarCOs could represent a new kind of data relay to Earth. InSight's success is independent of its CubeSat tagalongs.
InSight could teach us how Martian volcanoes were formed.
Mars is home to some impressive volcanic features. That includes Tharsis  a plateau with some of the biggest volcanoes in the solar system. Heat escaping from deep within the planet drives the formation of these types of features, as well as many others on rocky planets. InSight includes a selfhammering heat probe that will burrow down to 16 feet (5 meters) into the Martian soil to measure the heat flow from the planet's interior for the first time. Combining the rate of heat flow with other InSight data will reveal how energy within the planet drives changes on the surface.
Mars is a time machine
Studying Mars lets us travel to the ancient past. While Earth and Venus have tectonic systems that have destroyed most of the evidence of their early history, much of the Red Planet has remained static for more than 3 billion years. Because Mars is just onethird the size of Earth and Venus, it contains less energy to power the processes that change a planet's structure. That makes it a fossil planet in many ways, with the secrets of our solar system's early history locked deep inside.
Learn more about InSight's mission goals and instrumentation at a live public talk, part of JPL's von Karman lecture series, on Thursday, Feb. 22 at 7 p.m. PST (10 p.m. EST). The event will be streamed live on https://www.youtube.com/NASAJPL/live .
More information about InSight is at:
https://mars.nasa.gov/insight
News Media Contact Andrew Good Jet Propulsion Laboratory, Pasadena, Calif. 8183932433 andrew.c.good@jpl.nasa.gov
2018037
https://www.jpl.nasa.gov/news/news.php?feature=7067&utm_source=iContact&utm_medium=email&utm_campaign=NASAJPL&utm_content=mars201802221

Public Events  Overview Tours Lecture Series Speakers Bureau Team Competitions Special Events
The von Kármán Lecture Series: 2018
Looking Deep: The InSight Mission to Mars
February 23
The InSight mission, scheduled to launch in May, 2018, will be the first NASA mission to observe the deep interior of Mars. Mars, Earth, Venus, and Mercury are as similar as they are different, and the view granted by our human and robotic eyes only scratches the surface. By sending instruments that can teach us about the interior of Mars, we learn about the history and evolution of all these familiar planets. The instruments InSight will bring to Elysium Planitia are conceptually simple, yet also sensitive, delicate, and complex. The spacecraft itself uses proven hardware from previous missions to Mars’ surface, but also features new activities crucial to the success of InSight science.
Come dig deep into the workings of Earth’s next trip to the Red Planet. InSight (Interior Exploration Using Seismic Investigations, Geodesy, and Heat Transport) is a mission in NASA’s Discovery Program. It is led by Principal Investigator, Dr. Bruce Banerdt, and is managed by the Jet Propulsion Laboratory (JPL). InSight is a collaborative partnership of NASA, Lockheed Martin Space Systems, Cetre National d’Etudes Spatiales (CNES) of France, and the Deutsches Zentrum für Luft und Raumfahrt (DLR).
Speaker: Troy Lee Hudson Technologist, at the NASA Jet Propulsion Laboratory Instrument Systems Engineer for the InSight mission HeatFlow and Physical Properties Package (HP3).
Location: Friday, February 23, 2018, 7pm The Vosloh Forum at Pasadena City College 1570 East Colorado Blvd. Pasadena, CA › Directions
Webcast: Click here to watch the recorded event on Ustream
https://www.jpl.nasa.gov/events/lectures_archive.php?year=2018&month=2&utm_source=iContact&utm_medium=email&utm_campaign=NASAJPL&utm_content=vonkarman201802221
Historically, the distance to the visible horizon has long been vital to survival and successful navigation, especially at sea, because it determined an observer's maximum range of vision and thus of communication, with all the obvious consequences for safety and the transmission of information that this range implied.
YANIS.  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 24 Fév à 9:34  
 Conceptuellement, l’horizon est la limite de ce que l'on peut observer, du fait de sa propre position ou situation. Ce concept simple se décline en physique, philosophie, communication, et bien d'autres domaines :
This importance lessened with the development of the radio and the telegraph, but even today, when flying an aircraft under visual flight rules, a technique called attitude flying is used to control the aircraft, where the pilot uses the visual relationship between the aircraft's nose and the horizon to control the aircraft. A pilot can also retain his or her spatial orientation by referring to the horizon.
In many contexts, especially perspective drawing, the curvature of the Earth is disregarded and the horizon is considered the theoretical line to which points on any horizontal plane converge (when projected onto the picture plane) as their distance from the observer increases. For observers near sea level the difference between this geometrical horizon (which assumes a perfectly flat, infinite ground plane) and the true horizon (which assumes a spherical Earth surface) is imperceptible to the naked eye[dubious – discuss] (but for someone on a 1000meter hill looking out to sea the true horizon will be about a degree below a horizontal line).
In astronomy the horizon is the horizontal plane through the eyes of the observer. It is the fundamental plane of the horizontal coordinate system, the locus of points that have an altitude of zero degrees. While similar in ways to the geometrical horizon, in this context a horizon may be considered to be a plane in space, rather than a line on a picture plane. Distance to the horizon
One typically sees further along the Earth's curved surface than a simple geometric calculation allows for because of refraction error. If the ground, or water, surface is colder than the air above it, a cold, dense layer of air forms close to the surface, causing light to be refracted downward as it travels, and therefore, to some extent, to go around the curvature of the Earth. The reverse happens if the ground is hotter than the air above it, as often happens in deserts, producing mirages. As an approximate compensation for refraction, surveyors measuring distances longer than 300 feet subtract 14% from the calculated curvature error and ensure lines of sight are at least 5 feet from the ground, to reduce random errors created by refraction. Typical desert horizon
However, ignoring the effect of atmospheric refraction, distance to the horizon from an observer close to the Earth's surface is about[5]
d ≈ 3.57 h , {\displaystyle d\approx 3.57{\sqrt {h}}\,,} d \approx 3.57\sqrt{h} \,,
where d is in kilometres and h is height above ground level in metres. The constant 3.57 has units of km/m½.
Examples:
For an observer standing on the ground with h = 1.70 metres (5 ft 7 in), the horizon is at a distance of 4.7 kilometres (2.9 mi). For an observer standing on the ground with h = 2 metres (6 ft 7 in), the horizon is at a distance of 5 kilometres (3.1 mi). For an observer standing on a hill or tower of 100 metres (330 ft) in height, the horizon is at a distance of 36 kilometres (22 mi). For an observer standing at the top of the Burj Khalifa (828 metres (2,717 ft) in height), the horizon is at a distance of 103 kilometres (64 mi). For an observer atop Mount Everest (8,848 metres (29,029 ft) in altitude), the horizon is at a distance of 336 kilometres (209 mi).
With d in miles (i.e. "land miles" of 5,280 feet (1,609.344 m)[5]) and h in feet,
d ≈ 1.5 h ≈ 1.22 h . {\displaystyle d\approx {\sqrt {1.5h}}\approx 1.22{\sqrt {h}}\,.} {\displaystyle d\approx {\sqrt {1.5h}}\approx 1.22{\sqrt {h}}\,.}
Where the constant 1.22 has units of mi/ft½. Examples, assuming no refraction:
For an observer on the ground with eye level at h = 5 ft 7 in (1.70 m), the horizon is at a distance of 2.9 miles (4.7 km). For an observer standing on a hill or tower 100 feet (30 m) in height, the horizon is at a distance of 12.2 miles (19.6 km). For an observer on the summit of Aconcagua (22,841 feet (6,962 m) in height), the sealevel horizon to the west is at a distance of 184 miles (296 km). For a U2 pilot, whilst flying at its service ceiling 70,000 feet (21,000 m), the horizon is at a distance of 324 miles (521 km)
Other planets
On terrestrial planets and other solid celestial bodies with negligible atmospheric effects, the distance to the horizon for a "standard observer" varies as the square root of the planet's radius. Thus, the horizon on Mercury is 62% as far away from the observer as it is on Earth, on Mars the figure is 73%, on the Moon the figure is 52%, on Mimas the figure is 18%, and so on. Geometrical model Geometrical basis for calculating the distance to the horizon, secant tangent theorem Geometrical distance to the horizon, Pythagorean theorem Three types of horizon
If the Earth is assumed to be a featureless sphere (rather than an oblate spheroid) with no atmospheric refraction, then the distance to the horizon can easily be calculated.[6]
The secanttangent theorem states that
O C 2 = O A × O B . {\displaystyle \mathrm {OC} ^{2}=\mathrm {OA} \times \mathrm {OB} \,.} \mathrm{OC}^2 = \mathrm{OA} \times \mathrm{OB} \,.
Make the following substitutions:
d = OC = distance to the horizon D = AB = diameter of the Earth h = OB = height of the observer above sea level D+h = OA = diameter of the Earth plus height of the observer above sea level
The formula now becomes
d 2 = h ( D + h ) {\displaystyle d^{2}=h(D+h)\,\!} d^2 = h(D+h)\,\!
or
d = h ( D + h ) = h ( 2 R + h ) , {\displaystyle d={\sqrt {h(D+h)}}={\sqrt {h(2R+h)}}\,,} d = \sqrt{h(D+h)} =\sqrt{h(2R+h)}\,,
where R is the radius of the Earth.
The equation can also be derived using the Pythagorean theorem. Since the line of sight is a tangent to the Earth, it is perpendicular to the radius at the horizon. This sets up a right triangle, with the sum of the radius and the height as the hypotenuse. With
d = distance to the horizon h = height of the observer above sea level R = radius of the Earth
referring to the second figure at the right leads to the following:
( R + h ) 2 = R 2 + d 2 {\displaystyle (R+h)^{2}=R^{2}+d^{2}\,\!} (R+h)^2 = R^2 + d^2 \,\! R 2 + 2 R h + h 2 = R 2 + d 2 {\displaystyle R^{2}+2Rh+h^{2}=R^{2}+d^{2}\,\!} R^2 + 2Rh + h^2 = R^2 + d^2 \,\! d = h ( 2 R + h ) . {\displaystyle d={\sqrt {h(2R+h)}}\,.} d = \sqrt{h(2R + h)} \,.
Another relationship involves the distance s along the curved surface of the Earth to the horizon; with γ in radians,
s = R γ ; {\displaystyle s=R\gamma \,;} s = R \gamma \,;
then
cos γ = cos s R = R R + h . {\displaystyle \cos \gamma =\cos {\frac {s}{R}}={\frac {R}{R+h}}\,.} \cos \gamma = \cos\frac{s}{R}=\frac{R}{R+h}\,.
Solving for s gives
s = R cos − 1 R R + h . {\displaystyle s=R\cos ^{1}{\frac {R}{R+h}}\,.} s=R\cos^{1}\frac{R}{R+h} \,.
The distance s can also be expressed in terms of the lineofsight distance d; from the second figure at the right,
tan γ = d R ; {\displaystyle \tan \gamma ={\frac {d}{R}}\,;} \tan \gamma = \frac {d} {R} \,;
substituting for γ and rearranging gives
s = R tan − 1 d R . {\displaystyle s=R\tan ^{1}{\frac {d}{R}}\,.} s=R\tan^{1}\frac{d}{R} \,.
The distances d and s are nearly the same when the height of the object is negligible compared to the radius (that is, h ≪ R). Approximate geometrical formulas Graphs of distances to the true horizon on Earth for a given height h. s is along the surface of the Earth, d is the straight line distance, and ~d is the approximate straight line distance assuming h << the radius of the Earth, 6371 km. In the SVG image, hover over a graph to highlight it.
If the observer is close to the surface of the earth, then it is valid to disregard h in the term (2R + h), and the formula becomes
d = 2 R h . {\displaystyle d={\sqrt {2Rh}}\,.} d = \sqrt{2Rh} \,.
Using kilometres for d and R, and metres for h, and taking the radius of the Earth as 6371 km, the distance to the horizon is
d ≈ 2 ⋅ 6371 ⋅ h / 1000 ≈ 3.570 h , {\displaystyle d\approx {\sqrt {2\cdot 6371\cdot {h/1000}}}\approx 3.570{\sqrt {h}}\,,} d \approx \sqrt{2\cdot6371\cdot{h/1000}} \approx 3.570\sqrt{h} \,,.
Using imperial units, with d and R in statute miles (as commonly used on land), and h in feet, the distance to the horizon is
d ≈ 2 ⋅ 3963 ⋅ h / 5280 ≈ 1.5 h ≈ 1.22 h {\displaystyle d\approx {\sqrt {2\cdot 3963\cdot {h/5280}}}\approx {\sqrt {1.5h}}\approx 1.22{\sqrt {h}}} {\displaystyle d\approx {\sqrt {2\cdot 3963\cdot {h/5280}}}\approx {\sqrt {1.5h}}\approx 1.22{\sqrt {h}}}.
If d is in nautical miles, and h in feet, the constant factor is about 1.06, which is close enough to 1 that it is often ignored, giving:
d ≈ h {\displaystyle d\approx {\sqrt {h}}} d \approx \sqrt h
These formulas may be used when h is much smaller than the radius of the Earth (6371 km or 3959 mi), including all views from any mountaintops, airplanes, or highaltitude balloons. With the constants as given, both the metric and imperial formulas are precise to within 1% (see the next section for how to obtain greater precision). Exact formula for a spherical Earth
If h is significant with respect to R, as with most satellites, then the approximation made previously is no longer valid, and the exact formula is required:
d = 2 R h + h 2 , {\displaystyle d={\sqrt {2Rh+h^{2}}}\,,} d = \sqrt{2Rh + h^2} \,,
where R is the radius of the Earth (R and h must be in the same units). For example, if a satellite is at a height of 2000 km, the distance to the horizon is 5,430 kilometres (3,370 mi); neglecting the second term in parentheses would give a distance of 5,048 kilometres (3,137 mi), a 7% error. Objects above the horizon Geometrical horizon distance
To compute the greatest distance at which an observer can see the top of an object above the horizon, compute the distance to the horizon for a hypothetical observer on top of that object, and add it to the real observer's distance to the horizon. For example, for an observer with a height of 1.70 m standing on the ground, the horizon is 4.65 km away. For a tower with a height of 100 m, the horizon distance is 35.7 km. Thus an observer on a beach can see the top of the tower as long as it is not more than 40.35 km away. Conversely, if an observer on a boat (h = 1.7 m) can just see the tops of trees on a nearby shore (h = 10 m), the trees are probably about 16 km away.
Referring to the figure at the right, the top of the lighthouse will be visible to a lookout in a crow's nest at the top of a mast of the boat if
D B L < 3.57 ( h B + h L ) , {\displaystyle D_{\mathrm {BL} }<3.57\,({\sqrt {h_{\mathrm {B} }}}+{\sqrt {h_{\mathrm {L} }}})\,,} D_\mathrm{BL} < 3.57\,(\sqrt{h_\mathrm{B}} + \sqrt{h_\mathrm{L}}) \,,
where DBL is in kilometres and hB and hL are in metres. A view across a 20kmwide bay in the coast of Spain. Note the curvature of the Earth hiding the base of the buildings on the far shore.
As another example, suppose an observer, whose eyes are two metres above the level ground, uses binoculars to look at a distant building which he knows to consist of thirty storeys, each 3.5 metres high. He counts the storeys he can see, and finds there are only ten. So twenty storeys or 70 metres of the building are hidden from him by the curvature of the Earth. From this, he can calculate his distance from the building:
D ≈ 3.57 ( 2 + 70 ) {\displaystyle D\approx 3.57({\sqrt {2}}+{\sqrt {70}})} D \approx 3.57(\sqrt{2}+\sqrt{70})
which comes to about 35 kilometres.
It is similarly possible to calculate how much of a distant object is visible above the horizon. Suppose an observer's eye is 10 metres above sea level, and he is watching a ship that is 20 km away. His horizon is:
3.57 10 {\displaystyle 3.57{\sqrt {10}}} 3.57 \sqrt{10}
kilometres from him, which comes to about 11.3 kilometres away. The ship is a further 8.7 km away. The height of a point on the ship that is just visible to the observer is given by:
h ≈ ( 8.7 3.57 ) 2 {\displaystyle h\approx \left({\frac {8.7}{3.57}}\right)^{2}} h\approx\left(\frac{8.7}{3.57}\right)^2
which comes to almost exactly six metres. The observer can therefore see that part of the ship that is more than six metres above the level of the water. The part of the ship that is below this height is hidden from him by the curvature of the Earth. In this situation, the ship is said to be hulldown. Effect of atmospheric refraction
If the Earth were an airless world like the Moon, the above calculations would be accurate. However, Earth has an atmosphere of air, whose density and refractive index vary considerably depending on the temperature and pressure. This makes the air refract light to varying extents, affecting the appearance of the horizon. Usually, the density of the air just above the surface of the Earth is greater than its density at greater altitudes. This makes its refractive index greater near the surface than at higher altitudes, which causes light that is travelling roughly horizontally to be refracted downward.[7] This makes the actual distance to the horizon greater than the distance calculated with geometrical formulas. With standard atmospheric conditions, the difference is about 8%.[citation needed] This changes the factor of 3.57, in the metric formulas used above, to about 3.86. This correction can be, and often is, applied as a fairly good approximation when conditions are close to standard. When conditions are unusual, this approximation fails. Refraction is strongly affected by temperature gradients, which can vary considerably from day to day, especially over water. In extreme cases, usually in springtime, when warm air overlies cold water, refraction can allow light to follow the Earth's surface for hundreds of kilometres. Opposite conditions occur, for example, in deserts, where the surface is very hot, so hot, lowdensity air is below cooler air. This causes light to be refracted upward, causing mirage effects that make the concept of the horizon somewhat meaningless. Calculated values for the effects of refraction under unusual conditions are therefore only approximate.[5] Nevertheless, attempts have been made to calculate them more accurately than the simple approximation described above.
Outside the visual wavelength range, refraction will be different. For radar (e.g. for wavelengths 300 to 3 mm i.e. frequencies between 1 and 100 GHz) the radius of the Earth may be multiplied by 4/3 to obtain an effective radius giving a factor of 4.12 in the metric formula i.e. the radar horizon will be 15% beyond the geometrical horizon or 7% beyond the visual. The 4/3 factor is not exact, as in the visual case the refraction depends on atmospheric conditions.
Integration method—Sweer
If the density profile of the atmosphere is known, the distance d to the horizon is given by[8]
d = R E ( ψ + δ ) , {\displaystyle d={{R}_{\text{E}}}\left(\psi +\delta \right)\,,} d={{R}_{\text{E}}}\left( \psi +\delta \right) \,,
where RE is the radius of the Earth, ψ is the dip of the horizon and δ is the refraction of the horizon. The dip is determined fairly simply from
cos ψ = R E μ 0 ( R E + h ) μ , {\displaystyle \cos \psi ={\frac {{R}_{\text{E}}{\mu }_{0}}{\left({{R}_{\text{E}}}+h\right)\mu }}\,,} \cos \psi = \frac{{R}_{\text{E}}{\mu}_{0}}{\left( {{R}_{\text{E}}}+h \right)\mu } \,,
where h is the observer's height above the Earth, μ is the index of refraction of air at the observer's height, and μ0 is the index of refraction of air at Earth's surface.
The refraction must be found by integration of
δ = − ∫ 0 h tan ϕ d μ μ , {\displaystyle \delta =\int _{0}^{h}{\tan \phi {\frac {{\text{d}}\mu }{\mu }}}\,,} \delta =\int_{0}^{h}{\tan \phi \frac{\text{d}\mu }{\mu }} \,,
where ϕ {\displaystyle \phi \,\!} \phi \,\! is the angle between the ray and a line through the center of the Earth. The angles ψ and ϕ {\displaystyle \phi \,\!} \phi \,\! are related by
ϕ = 90 ∘ − ψ . {\displaystyle \phi =90{}^{\circ }\psi \,.} \phi =90{}^\circ \psi \,.
Simple method—Young
A much simpler approach, which produces essentially the same results as the firstorder approximation described above, uses the geometrical model but uses a radius R′ = 7/6 RE. The distance to the horizon is then[5]
d = 2 R ′ h . {\displaystyle d={\sqrt {2R^{\prime }h}}\,.} d=\sqrt{2 R^\prime h} \,.
Taking the radius of the Earth as 6371 km, with d in km and h in m,
d ≈ 3.86 h ; {\displaystyle d\approx 3.86{\sqrt {h}}\,;} d \approx 3.86 \sqrt{h} \,;
with d in mi and h in ft,
d ≈ 1.32 h . {\displaystyle d\approx 1.32{\sqrt {h}}\,.} d \approx 1.32 \sqrt{h} \,.
Results from Young's method are quite close to those from Sweer's method, and are sufficiently accurate for many purposes. Curvature of the horizon
This section has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages) This section does not cite any sources. (June 2013) This section needs expansion with: examples and additional citations. You can help by adding to it. (June 2013) The curvature of the horizon is easily seen in this photograph, taken from a space shuttle at an altitude of 226 km in 2008.
From a point above the surface the horizon appears slightly bent (it is a circle). There is a basic geometrical relationship between this visual curvature κ {\displaystyle \kappa } \kappa , the altitude h {\displaystyle h} h, and the Earth's radius R {\displaystyle R} R, . It is
κ = ( 1 + h R ) 2 − 1 . {\displaystyle \kappa ={\sqrt {\left(1+{\frac {h}{R}}\right)^{2}1}}\ .} \kappa=\sqrt{\left(1+\frac{h}{R}\right)^21}\ .
The curvature is the reciprocal of the curvature angular radius in radians. A curvature of 1 appears as a circle of an angular radius of 57.3° corresponding to an altitude of approximately 2640 km above the Earth's surface. At an altitude of 10 km (33,000 ft, the typical cruising altitude of an airliner) the mathematical curvature of the horizon is about 0.056, the same curvature of the rim of circle with a radius of 10 m that is viewed from 56 cm directly above the center of the circle. However, the apparent curvature is less than that due to refraction of light in the atmosphere and because the horizon is often masked by high cloud layers that reduce the altitude above the visual surface. Vanishing points Two points on the horizon are at the intersections of the lines extending the segments representing the edges of the building in the foreground. The horizon line coincides here with the line at the top of the doors and windows. Main article: Vanishing point
The horizon is a key feature of the picture plane in the science of graphical perspective. Assuming the picture plane stands vertical to ground, and P is the perpendicular projection of the eye point O on the picture plane, the horizon is defined as the horizontal line through P. The point P is the vanishing point of lines perpendicular to the picture. If S is another point on the horizon, then it is the vanishing point for all lines parallel to OS. But Brook Taylor (1719) indicated that the horizon plane determined by O and the horizon was like any other plane:
The term of Horizontal Line, for instance, is apt to confine the Notions of a Learner to the Plane of the Horizon, and to make him imagine, that that Plane enjoys some particular Privileges, which make the Figures in it more easy and more convenient to be described, by the means of that Horizontal Line, than the Figures in any other plane;…But in this Book I make no difference between the Plane of the Horizon, and any other Plane whatsoever...[9][10]
The peculiar geometry of perspective where parallel lines converge in the distance, stimulated the development of projective geometry which posits a point at infinity where parallel lines meet. In her book Geometry of an Art (2007), Kirsti Andersen described the evolution of perspective drawing and science up to 1800, noting that vanishing points need not be on the horizon. In a chapter titled "Horizon", John Stillwell recounted how projective geometry has led to incidence geometry, the modern abstract study of line intersection. Stillwell also ventured into foundations of mathematics in a section titled "What are the Laws of Algebra ?" The "algebra of points", originally given by Karl von Staudt deriving the axioms of a field was deconstructed in the twentieth century, yielding a wide variety of mathematical possibilities. Stillwell states
This discovery from 100 years ago seems capable of turning mathematics upside down, though it has not yet been fully absorbed by the mathematical community. Not only does it defy the trend of turning geometry into algebra, it suggests that both geometry and algebra have a simpler foundation than previously thought.[11]
See also
Aerial landscape art Atmospheric refraction Dawn Dusk Horizontal and vertical Landscape Landscape art Limb[disambiguation needed] Limb darkening Lunar limb Sextant
References
"Offing". Webster's Third New International Dictionary (Unabridged ed.). Pronounced, "HorIzon". Liddell, Henry George & Scott, Robert. "ὁρίζων". A GreekEnglish Lexicon. Perseus Digital Library. Archived from the original on June 5, 2011. Retrieved April 19, 2011. Liddell, Henry George & Scott, Robert. "ὁρίζω". A GreekEnglish Lexicon. Perseus Digital Library. Archived from the original on June 5, 2011. Retrieved April 19, 2011. Liddell, Henry George & Scott, Robert. "ὅρος". A GreekEnglish Lexicon. Perseus Digital Library. Archived from the original on June 5, 2011. Retrieved April 19, 2011. Young, Andrew T. "Distance to the Horizon". Green Flash website (Sections: Astronomical Refraction, Horizon Grouping). San Diego State University Department of Astronomy. Archived from the original on October 18, 2003. Retrieved April 16, 2011. Plait, Phil (15 January 2009). "How far away is the horizon?". Discover. Bad Astronomy. Kalmbach Publishing Co. Archived from the original on 29 March 2017. Retrieved 20170328. Proctor, Richard Anthony; Ranyard, Arthur Cowper (1892). Old and New Astronomy. Longmans, Green and Company. p. 73. Archived from the original on 20170329. Sweer, John (1938). "The Path of a Ray of Light Tangent to the Surface of the Earth". Journal of the Optical Society of America. 28: 327–329. doi:10.1364/JOSA.28.000327. (Subscription required (help)). Taylor, Brook. New Principles of Perspective. p. 1719. Anderson, Kirsti (1991). "Brook Taylor's Work on Linear Perspective". Springer. p. 151. ISBN 0387974865.
Stillwell, John (2006). "Yearning for the Impossible". Horizon. A K Peters, Ltd. pp. 47–76. ISBN 156881254X.
Further reading
Young, Andrew T. "Dip of the Horizon". Green Flash website (Sections: Astronomical Refraction, Horizon Grouping). San Diego State University Department of Astronomy. Retrieved April 16, 2011.
Sciences et techniques Géologie
Un horizon en pédologie est une couche du sol, homogène et parallèle à la surface.
Informatique
Horizon, un logiciel SIGB de la société SirsiDynix ; New Horizon Interactive, société de logiciels ; Horizon, un jeu d'arcade.
Physique
L’horizon est un cercle centré sur l’observateur entre le ciel et la Terre, tenant compte de la courbure de cette dernière ; L’horizon des particules est la limite de la région de l'espacetemps susceptible d'influencer un point donné ; En particulier, l’horizon cosmologique est la limite de l'univers visible depuis la Terre, est, sous certaines conditions, un horizon des particules ; L’horizon des évènements est la limite de la région de l'espacetemps influençable depuis un point donné ; En particulier, l’horizon d'un trou noir est la frontière entre un trou noir et le reste de l'univers, est un horizon des événements.
Sciences humaines
Un horizon en philosophie, un concept à rapprocher de l'aveuglement ; L’horizon, la classification chronologique des périodes précolombiennes dans les Andes centrales (Bolivie et Pérou).
Technique
L’horizonradar est la distance maximale que peut atteindre le faisceau radar à un angle de site nul.
Arts et culture Cinéma / télévision
L'Horizon est un film de Lev Koulechov (1932) ; Horizons sans fin, film de Jean Dréville (1953) ; L'Horizon est un film de Jacques Rouffio (1967) ; Event Horizon, le vaisseau de l'audelà est un film américain de Paul W. S. Anderson (1997) ; Horizon est une émission de télévision diffusée par la BBC.
Jeu vidéo
Horizon, shoot 'em up d'Irem sorti en 1985 Horizon, jeu 4X de L3O Interactive sorti en 2014 Horizon Zero Dawn, actionRPG de Guerrilla Games à paraître en 2016
Musique
Horizon est un single de The Cinematic Orchestra sorti en 2002 ; L'Horizon est un album de musique de Dominique A sorti en 2006 ; Horizons est un album de Détroit sorti en 2013 ; Horizons est une chanson du groupe Genesis sorti en 1972. Horizon est une chanson de l'album Private Collection de Jon & Vangelis sortie en 1983
Littérature
Les Horizons vaincus, un livre de l'alpiniste italien Reinhold Messner relatant son ascension en solitaire et sans oxygène de l'Everest ; Horizon est le quatrième et dernier tome de la tétralogie de fantasy Le Couteau du partage de Lois McMaster Bujold ; L'Horizon est un roman de Patrick Modiano paru en 2010.
Médias Presse
Horizons, un quotidien algérien en langue française ; Horizons, le magazine de la recherche du Fonds national suisse de la recherche scientifique (FNS) et des Académies suisses des sciences (également édité en allemand sous le titre Horizonte).
Radio
Horizon, une radio locale française de catégorie B, fondée en 1985 et diffusant ses programmes sur une partie de la région HautsdeFrance ; Horizon, une station de radio locale implantée en SeineMaritime, fondée en 1982.
Produits, services et organisations
Air Horizons, une compagnie aérienne française ; Horizons, une ancienne attraction du parc Epcot à Walt Disney World Resort ; La SimcaTalbot Horizon, une voiture des marques Simca et Talbot ; Classe Horizon, frégates francoitaliennes ; Horizon, un navire de croisière construit en 1990 ; Réseau de bus Horizon, bus de l'agglomération de Châteauroux ; New Horizons, une sonde spatiale de la NASA pour l'étude de Pluton et de la ceinture de Kuiper.
Voir aussi
Sur les autres projets Wikimedia :
Horizon, sur Wikimedia Commons horizon, sur le Wiktionnaire Horizon, sur Wikiquote
Horizons lointains Ce lien renvoie vers une page d'homonymie Les Horizons perdus Ce lien renvoie vers une page d'homonymie Nouveaux Horizons Ce lien renvoie vers une page d'homonymie
Title Goonhilly Released 22/02/2018 10:39 am Copyright GES  Goonhilly Earth Station Ltd. Description
Goonhilly Earth Station, a commercial tracking station in Cornwall, UK, will be upgraded to provide Europe’s first deepspace services on a commercial basis.
Under the project, the station’s GHY6 antenna (seen here), built in 1985 and featuring a 32 mdiameter dish, will be upgraded to provide high bitrate data links for missions far from Earth – typically exceeding 2 million km.
These include not only missions to our somewhat closer Moon, but also to the asteroids and planetary destinations such as Mars.
More information
Major European Space Agency Project at Goonhilly
ESA ground station network Id 390564
http://www.esa.int/spaceinimages/Images/2018/02/Goonhilly2
MOSAÏQUE ET SENTIMENTS DU CITOYEN TIGNARD YANIS ALIAS TAY La chouette effraie  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 24 Fév à 9:34  
 Evgenia Armanovna Medvedeva (alt. spelling: Yevgenia Medvedeva;[9] Russian: Евгения Армановна Медведева, IPA: [jɪvˈɡʲenʲɪjə mʲɪˈdvʲedʲɪvə]; born 19 November 1999), also known as Zhenya Medvedeva (Russian: Женя Медведева), is a Russian figure skater. She is the 2018 Olympic silver medalist, a twotime world champion (2016, 2017), a twotime European champion (2016, 2017), a twotime Grand Prix Final champion (2015, 2016), and a twotime Russian national champion (2016, 2017). Earlier in her career, she won the 2015 World Junior Championships, the 2014 Junior Grand Prix Final, and the 2015 Russian Junior Championships.[10] She won the silver medal in the ladies’ singles event at the 2018 Olympic Games in Pyeongchang.
#30AnsPernaut Compte certifié @TF1LeJT 22 févr. Très ému, @pernautjp découvre une nouvelle surprise : les gentils mots des téléspectateurs.
TIGNARD YANIS @TIGNARDYANIS En réponse à @TF1LeJT @pernautjp
MONSIEUR PERNAUT JEAN PIERRE. JE VOUS SOUHAITE UN JOYEUX ANNIVERSAIRE. VOUS FAITES PARTI DE CEUX QUI ONT PERMIS À LA FRANCE D'ÊTRE CONVIVIALE, IMPERTINENTE ET CRÉATIVE. VOUS ÊTES UN PILLIER DE LA RÉPUBLIQUE DANS VOTRE AMOUR DU PEUPLE. TAY
FÉLICITATIONS À MADEMOISELLE ZAGITOVA ALINA. UNE NOUVELLE GÉNÉRATION RUSSE EST EN TRAIN DE NAÎTRE ET CETTE JEUNE FEMME CONFIRME LA RÉALITÉ DE L'EXISTENCE, DE LA CONSCIENCE ET DE LA CONVICTION: ELLE A SU ÉMERGER DANS SA TÊTE ET SA VOLONTÉ. TAY
Alina Ilnazovna Zagitova (pron. ZahGHITtohvah; Russian: Алина Ильназовна Загитова;[1] born 18 May 2002) is a Russian figure skater. She is the 2018 Olympic champion, 2018 European champion, 2017–18 Grand Prix Final champion, and 2018 Russian national champion. Zagitova won a silver medal in the team event at the 2018 Winter Olympics, as part of the OAR's team.
Earlier in her career, she won gold at the 2017 World Junior Championships and at the 2016–17 Junior Grand Prix Final, where she became the first junior lady to achieve a total score above the 200 mark, scoring 207.43 points.

22 February 2018
Until now, if you’re an entrepreneur planning future missions beyond Earth, you’d have to ask a big space agency to borrow their deepspace antennas. Now, thanks to the UK’s county of Cornwall and ESA, you’ll have a commercial option, too.
If you’re planning on flying a robotic or even human mission in the near future to the Moon, an asteroid or even Mars, one indispensable requirement you’ll face is the need for at least one deepspace tracking dish to communicate with your craft.
Today, however, there’s no commercial deepspace service available to rent – and building a new station from scratch all on your own is rather pricey, although would be justified for a spacecraft travelling to exotic locations like Jupiter.
ESA has three deepspace dishes, in Australia, Spain and Argentina, that provide leadingedge performance and fullsky coverage for tracking and communicating with missions like Mars Express, Gaia and ExoMars. BepiColombo at Mercury
Later this year, they will add the new BepiColombo mission to Mercury and, in the near future, ESA’s Solar Orbiter, Euclid and Cheops.
“The amount of science data flowing in from ESA’s current missions, not to mention from future missions with improved instruments, is growing strongly,” says ESA’s Pier Bargellini, responsible for network operations.
“By the middle of the next decade, ESA’s deepspace communication needs for supporting today’s missions, like ExoMars, and upcoming spacecraft, like Juice, is expected to exceed our present capacity by around half.
“We are considering urgently how to bridge this gap.”
This is why ESA engineering teams are excited by a new initiative aimed at redeveloping part of Goonhilly Earth Station, an existing commercial station in Cornwall, UK, to enable it to provide Europe’s first deepspace tracking services on a commercial basis.
Under the project, a 32 mdiameter dish built in 1985 will be upgraded to provide fast data links for missions far beyond Earth – typically exceeding 2 million km.
In future, once commercial capacity is available, ESA’s deepspace antenna network will focus on supporting sophisticated missions demanding highperformance systems.
Test links will be made with ESA missions such as Mars Express, one of the first times an Agency mission communicates with a nonESA, nonNASA station from another planet. Mars Express monitored the flyby of comet Siding Spring on 19 October 2014 Mars Express
The project will be initially funded through a €9.5 million investment from the UK’s Cornwall & Isles of Scilly Local Enterprise Partnership, a public–private regional economic development body, and will later include a smaller investment from ESA.
“Once the station upgrade work is complete, in about 24 months, Goonhilly will be able to complement ESA’s own stations, and provide deepspace tracking for the Agency’s missions as well as those of other space agencies or from private space startups aiming to exploit the Moon or mine asteroids,” notes KlausJürgen Schulz, responsible of ESA ground station engineering.
Goonhilly, established in 1962 and at one time the largest satellite station in the world, with over 60 dishes of varying size, is well known in the UK. Its antennas have brought iconic images to UK TV viewers, including Muhammad Ali fights, the Olympic Games, the Apollo 11 Moon landing and 1985’s Live Aid concert.
With the growing demand for deepspace tracking for both space agencies and new commercial space companies, the Goonhilly upgrade is an excellent example of how ESA can foster new business for European industry through engineering contracts to transform existing antennas into stateofthe art deepspace ground stations.
“Upgrading Goonhilly and building up a commercial capability to support future exploration missions is good for ESA and good for European science and industry,” says Rolf Densing, ESA’s Director of Operations.
“It’s also excellent value for European taxpayers.”
http://www.esa.int/Our_Activities/Operations/Estrack/Goonhilly_goes_deep_space
ET
Title Carbon Cycle Released: 21/02/2018 Length 00:03:20 Language English Footage Type Animation Copyright ESA/Planetary Visions Description
As part of the way Earth works as a system, carbon is continuously passed between the ocean, the land and the atmosphere. This involves a range of different processes, some of which can be observed by satellites. Human activity is disturbing these natural processes and causing a rise in atmospheric carbon dioxide. Satellites and ESA’s Climate Change Initiative are helping to improve our understanding of the carbon cycle and its role in climate change.
Learn more about the Climate Change Initiative
http://www.esa.int/spaceinvideos/Videos/2018/02/Carbon_Cycle
MOSAÏQUE ET SENTIMENTS DU CITOYEN TIGNARD YANIS ALIAS TAY La chouette effraie ET DE Y'BECCA Revenir en haut Aller en bas Voir le profil de l'utilisateur Envoyer un message privé http://www.atelieryannistignard.com En ligne  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 24 Fév à 9:34  
 TIGNARD YANIS @TIGNARDYANIS 17 h il y a 17 heures LE MURMURE DE L'EXISTENCE EST UNE HYPOTHÈSE LORSQUE L'HYPNOSE EXPOSE LA CONTRAINTE D'ACCEPTER UNE PRÉSENCE QUE L'ON ACCEPTE PAS ÊTRE SIENNE: UNE CIRCONSTANCE DE VIE QUE L'ON PORTE TEL UN PARASITE. TAY
DANS LE REJET DE LA VIE, IL Y A LONGTEMPS QUE LE SUJET FAIT PART DE SA SOLITUDE AU SOUFFLE. LE SILENCE SE PORTE AUX SAISONS TELS LES SOUPIRS QUI PEUPLENT LE TEMPS. L'HYPNOSE NE PEUT ENSEIGNER LA CERTITUDE CAR LA PEUR DEMEURE ENFOUIE. TAY
JE NE COMPRENDS PAS LA SOLLICITUDE QUE L'HYPNOSE VEUT APPELER SOUS FORME DE DÉLIVRANCE: IL Y A LE CONCEPT DU CONTEXTE QUI DONNE L'ATTRAIT D'IMPRESSION SUR LE SUPÉRIEUR DONNANT AINSI À L'ÉTHIQUE DE POUVOIR ATTENDRE LA LIBERTÉ SANS ARTIFICES. TAY
L'HYPNOSE EST UN ART ET IL POSSÈDE LA FACULTÉ DE GUÉRIR DANS LA PLUPART DES DOMAINES MÉDICAUX. LA SAGESSE DE LA CONSCIENCE EST UNE OEUVRE AUQUEL NOUS SOMMES AU BORD D'UN GOUFFRE: À NOUS DE DÉFINIR SI IL EST UNE CAVERNE, UN SENTIMENT OU UN UNIVERS. TAY
AINSI,
21 February 2018
Slowed by skimming through the very top of the upper atmosphere, ESA’s ExoMars has lowered itself into a planethugging orbit and is about ready to begin sniffing the Red Planet for methane.
The ExoMars Trace Gas Orbiter arrived at Mars in October 2016 to investigate the potentially biological or geological origin of trace gases in the atmosphere.
It will also serve as a relay, connecting rovers on the surface with their controllers on Earth.
But before any of this could get underway, the spacecraft had to transform its initial, highly elliptical fourday orbit of about 98 000 x 200 km into the final, much lower and circular path at about 400 km.
“Since March 2017, we’ve been conducting a terrifically delicate ‘aerobraking’ campaign, during which we commanded it to dip into the wispy, uppermost tendrils of the atmosphere once per revolution, slowing the craft and lowering its orbit,” says ESA flight director Michel Denis.
Good progress Access the video
“This took advantage of the faint drag on the solar wings, steadily transforming the orbit. It’s been a major challenge for the mission teams supported by European industry, but they’ve done an excellent job and we’ve reached our initial goal.
“During some orbits, we were just 103 km above Mars, which is incredibly close.”
The end of this effort came at 17:20 GMT on 20 February, when the craft fired its thrusters for about 16 minutes to raise the closest approach to the surface to about 200 km, well out of the atmosphere. This effectively ended the aerobraking campaign, leaving it in an orbit of about 1050 x 200 km. Visualisation of Venus Express during the aerobraking manoeuvre, which will see the spacecraft orbiting Venus at an altitude of around 130 km from 18 June to 11 July, 2014 Venus Express aerobraking 2014
“We already acquired experience with aerobraking on a test basis at the end of the Venus Express mission, which was not designed for aerobraking, in 2014,” says spacecraft operations manager Peter Schmitz.
“But this is the first time ESA has used the technique to achieve a routine orbit around another planet – and ExoMars was specifically designed for this.”
Aerobraking around an alien planet that is, typically, 225 million km away is an incredibly delicate undertaking. The thin upper atmosphere provides only gentle deceleration – at most some 17 mm/s each second. How small is this?
If you braked your car at this rate from an initial speed of 50 km/h to stop at a junction, you’d have to start 6 km in advance.
“Aerobraking works only because we spent significant time in the atmosphere during each orbit, and then repeated this over 950 times,” says Michel.
“Over a year, we’ve reduced the speed of the spacecraft by an enormous 3600 km/h, lowering its orbit by the necessary amount.”
In the next month, the control team will command the craft through a series of up to 10 orbittrimming manoeuvres, one every few days, firing its thrusters to adjust the orbit to its final twohour, circular shape at about 400 km altitude, expected to be achieved around midApril. Taking stereo images
The initial phases of science gathering, in midMarch, will be devoted to checking out the instruments and conducting preliminary observations for calibration and validation. The start of routine science observations should happen around 21 April.
“Then, the craft will be reoriented to keep its camera pointing downwards and its spectrometers towards the Sun, so as to observe the Mars atmosphere, and we can finally begin the longawaited science phase of the mission,” says Håkan Svedhem, ESA’s project scientist.
The main goal is to take a detailed inventory of trace gases, in particular seeking out evidence of methane and other gases that could be signatures of active biological or geological activity.
A suite of four science instruments will make complementary measurements of the atmosphere, surface and subsurface. Its camera will help to characterise features on the surface that may be related to tracegases sources, such as volcanoes.
It will also look for waterice hidden just below the surface, which along with potential trace gas sources could guide the choice for future mission landing sites. Relaying calls from rovers
April will also see the craft test its datarelay capability, a crucial aspect of its mission at Mars.
A NASAsupplied radio relay payload will catch data signals from US rovers on the surface and relay these to ground stations on Earth. Data relaying will get underway on a routine basis later in the summer.
Starting in 2021, once ESA’s own ExoMars rover arrives, the orbiter will provide datarelay services for both agencies and for a Russian surface science platform.
ExoMars is a joint endeavour between ESA and Roscosmos.
http://www.esa.int/Our_Activities/Operations/Surfing_complete
ET;
Title Saturn’s B ring peaks Released 19/02/2018 10:00 am Copyright NASA/JPL/SSI Description
While the Winter Olympics is in full swing in PyeongChang, South Korea, and many winter sport fanatics head to snowclad mountains to get their thrills on the slopes this skiseason, this dramatic mountain scene is somewhat offpiste – in Saturn’s rings to be precise.
These fluffy peaks are among the tallest seen in Saturn’s main rings, towering as high as 2.5 km above the plane of the rings, a significant deviation from the vertical thickness of the planet’s main rings, which is generally only about 10 m. They rise abruptly from the edge of the B ring to cast long shadows in this image.
But these mountains are far from solid: they are constantly changing accumulations of ring particles that respond to the gravity of moonlets and wavelike formations induced in the rings.
Part of the Cassini Division, between the B and the A rings, appears at the top of the image, showing ringlets in the inner division. This is one prominent region at the outer edge of the B ring where moonlets up to a kilometre or more in size are found. It is possible that these bodies significantly affect the ring material streaming past them and force the particles upward in a ‘splashing’ manner, in reality making them impossible to ski.
Images like this are only possible around the time of Saturn’s equinox, which occurs every halfSaturnyear, or about every 15 Earth years. The illumination geometry that accompanies equinox lowers the Sun’s angle to the ring plane and causes structures jutting out of the plane to cast long shadows across the rings.
This image was taken by the international Cassini spacecraft’s narrowangle camera on 26 July 2009, two weeks before the planet’s 11 August equinox, as the Sun shone directly edgeon to the ring plane.
This view looks toward the southern, sunlit side of the rings from about 32º below the ring plane. The view was acquired at a distance of 336 000 km from Saturn and at a Sun–Saturn–spacecraft, angle of 132º. Image scale is 2 km/ pixel and the image captures a 1200 kmlong section arcing along the outer edge of the B ring.
The image was previously highlighted in a release on 1 November 2010.
The Cassini mission is a cooperative project of NASA, ESA and Italy’s ASI space agency. The mission concluded in September 2017. Id 390415
https://www.esa.int/spaceinimages/Images/2018/02/Saturn_s_B_ring_peaks
MOSAÏQUE ET SENTIMENTS DU CITOYEN TIGNARD YANIS ALIAS TAY La chouette effraie ET DE Y'BECCA  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 24 Fév à 10:40  
 LA CHINE BOUDDHISTE, L'INDE COMMUNISTE, Y'BECCA ET LE TIBET.
LES ÉTOILES. DÉDIE AUX RÉPUBLIQUES DE L'INDE, DU NÉPAL ET DU TIBET.
ELLES ONT UNE ROTATION... LES DIFFÉRENTS ARC DE CERCLES CAR L’ÉQUATEUR ET LES PÔLES ONT UNE ROTATIONS LIES AUX DIFFÉRENTS COURANTS INTÉRIEUR DÉCRIT PAR LES ALBATROS DANS LEURS EXPLORATIONS DES NUAGES... L’OMÉGA EST UNE FAIBLE ÉTOILE, MALGRÉ TOUT, CERTAINS SCIENTIFIQUES SE SONT AMUSES à DONNER DES SENS DIFFÉRENTS à LA LETTRE OMÉGA.
LA LUMIÈRE ET DIFFÉRENTES GALAXIES ONT UNE RÉVOLUTION LIÉE AUX ROTATIONS PROVOQUANT DES ELLIPTIQUES AUX ORIGINES DES PREMIERS TROU NOIRS OU L'INVERSE DU MAGNÉTISME VIENT QUE LA MORT SERAI UNE VARIATION DES SUBSTANCES DANS LE MAGNÉTIQUE ENGENDRANT LE TERME.
DANS LA LUMIÈRE ET L'OMBRE, ON A RÉUSSI à SAVOIR QUE LE SOLEIL SE DÉPLAÇAIT DANS L'ESPACE: UN GRAIN MONTRE QUE RIEN N'EST IMMOBILE DANS LA CIRCONSTANCE DE L'APESANTEUR. LE VIDE N'EST DONC PAS IMMOBILE ET DANS CES DIFFÉRENTS PHÉNOMÈNES PRÉSENTS; NOUS PERCEVONS DES REPÈRES CAR CES DIFFÉRENTS PHÉNOMÈNES NOUS PERMETTENT D'AVOIR UN REPÈRE.: S'AMUSE NAGALÏÉW LA MOUETTE DANS CES THÉORIES SUR L'UNIVERS, LE PRÉSENT ET LA CIRCONSTANCE.
LE RENARD EST MUET, LA CHOUETTE JUBILE, LE LOUP EST ÉMERVEILLÉ ET LA CIGOGNE SAVOURE.
PUIS; L’ŒIL ARDENT, NAGALÏÉW LA MOUETTE REGARDE SON PÈRE MAGELLAN L'ALBATROS ET RAJOUTE:
" CERTAINES ÉTUDES ME PERMETTENT DE COMPRENDRE, CHER PÈRE QUE LES MATHS ET L'INFORMATIQUE NE MÉRITENT PAS QUE L'ON PASSE à COTÉ DU PLAISIRS DE LA JOIE ET DES LARMES ".
" NAGALÏÉW; IL EST TEMPS DE SAVOIR Où SE DIRIGE LE MONDE... IL EST TEMPS DE REALISER QU'IL FAUT INTERVENIR... IL EST TEMPS QU'IL FAUT FAIRE REAGIR.. " : LUI RÉPONDS SON PÈRE.
ALORS TAY LA CHOUETTE REGARDE NAGALÏÉW QU'IL A ÉLEVÉ DANS L'AMOUR DE JÉRUSALEM AUPRÈS DE SES PARENTS ET DIT :
" JE VAIS TE RÉCITER CE POÈME QUE J'AI ÉCRIS, NAGALÏÉW ET à VOUS, TOUS MES AMIS ET AMIES...
LE GARDIEN DU PHARE...
COMME J'AIMERAI QUE LES EAUX ME PORTENT DEVANT LES PORTES DU PHARE. J'EN SORTIRAI LE GARDIEN ET REFERMERAIT LA PORTE à DOUBLE TOUR... ALORS, JE MONTERAI EN HAUT DE LA TOUR, CETTE CITADELLE PRÉNOMMÉE LE PHARE AFIN D'Y ALLUMER LA LUMIÈRE: DE FLAMME OU D'ÉLECTRICITÉ.
LA MER, MAINTENANT, JE VEUX LA VOIR M'AVALER; JE GUIDERAI LES VOYAGEURS DEPUIS MON PHARE ET DANS MON RIEN. DANS LES CIRCONSTANCES DES MOUVEMENTS DE MARÉES, JE VERRAI LE CONFLIT ET LA PAIX DE LA COLÈRE ET DE LA SÉRÉNITÉ. JAMAIS, JE NE L’ÉTEINDRAI MURMURANT MA SOIF ET MA FOI EN L'EXISTENCE ET AU VERBE.
JE NE SUIS PAS EMPRISONNÉE CAR J'AI UNE LUMIÈRE: CELLE DE PRONONCER LIBERTÉ ET DE VOIR LA TEMPÊTE DÉBOUSSOLER LES ESPRITS DES GRANDES GUEULES... DANS LA FRATERNITÉ, LE GARDIEN DU PHARE VOGUE SUR LA MER... "
NAGALÏÉW REGARDE SON PARRAIN ET DIT: " UN RÊVE FOU QUE JÉRUSALEM ET LA RÉPUBLIQUE... UN RÊVE AUX HAUTEURS DU SOUFFLE, DE LA FRATERNITÉ ET DU PEUPLE."
" POUR LE RAYON VERT OU CHANTECLERC, LE COQ " DISENT LE RENARD ET LE LOUP... LE CANARI PORTE UN CHANT DE JUSTICE VERS LA NATURE.
" POUR LA CONSCIENCE, LA VÉRITÉ, L’ESPÉRANCE ET L’ÂME..." S'EXCLAME LA CIGOGNE ET MERLIN LE ROUGE GORGE DU NÉPAL.
ECRIT DU CITOYEN TIGNARD YANIS  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Sam 3 Mar à 4:15  
 LE SPLEEN, L'OBSCURANTISME, LE TERME, LA CLARTÉ, Y'BECCA ET LA NATURE. http://leclandesmouettes.bbflash.net/t731lespleenlobscurantismeletermeybeccaetlanature … http://leclandesmouettes.bbflash.net/t730lespleenlobscurantismelaclarteybeccaetlanature LA CHASSE AUX BALEINES, Y'BECCA, MON ÂME ET GREENPEACE. http://leclandesmouettes.bbflash.net/t729lachasseauxbaleinesybeccamonameetgreenpeace Daniel Balavoine  Tous les cris les SOS https://www.youtube.com/watch?v=voIINSw_y9Y TAY. Y'BECCA  
   yanis la chouette
Nombre de messages : 11658 Localisation : http://yanis.tignard.free.fr Date d'inscription : 12/11/2005
 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS Lun 21 Mar à 4:34  
 compagnon.yanis.tignard @Yanis_Tignard · 19 mars En réponse à @WhiteHouse et @POTUS LA RÉPUBLIQUE D'UKRAINE DEVRAIT ÊTRE AUTONOME DE LA COMMUNAUTÉ EUROPÉENNE ET INDÉPENDANTE DE LA CONFÉDÉRATION DE LA RUSSIE : AFFIRME LA COMMUNAUTÉ PARLEMENTAIRE D'IRLANDE DU NORD ! DANS L'HORIZON VERS LE VIVANT : BELFAST EST TOUJOURS DANS MON COEUR ! ELLE EST MA SŒUR. TAY
COMMUNAUTÉ PARLEMENTAIRE DU SAHARA OCCIDENTAL, QUI SERA AUTONOME DU MAROC ET INDÉPENDANTE DE L'ALGÉRIE, NE CHERCHERA NI À DUPER LES ALGERIENS ET LES MAROCAINS : UN SOCLE JUDICIAIRE POUR LA COHÉSION ET LA PAIX SI ON CROIT AUX ÊTRES ET AUX MAGISTRATURES ENTRE PEUPLES. Y'BECCA. TAY
COMMUNAUTÉ PARLEMENTAIRE DU SAHARA OCCIDENTAL REGARDE LA COMMUNAUTÉ PARLEMENTAIRE D'IRLANDE DU NORD ET LA RÉPUBLIQUE D'UKRAINE ET DIT : PAR ALLAH JUSQU'À YAHVÉ, VOUS ÊTES MES SŒURS DE SANG EN UN SERMENT DANS LE SOUFFLE DE L'ALGÉRIE ET LE VIVANT DU MAROC. Y'BECCA EN JÉRUSALEM. TAY
compagnon.yanis.tignard @Yanis_Tignard · 1 min L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS DANS LE DESTIN ET LA VIE: LE COEUR D'UN CONCEPT S'EST IGNORÉ LA FIN LORSQUE L'ON S'APERÇOIT QU'UN NOUVEL HORIZON SE PROFIL DEPUIS LE DÉPART DE LA PALPITATION ! LE SPLEEN, L'OBSCURANTISME, LE TERME, LA CLARTÉ, Y'BECCA ET LA NATURE. TAY
L'INTERROGATOIRE, POLICE CRIMINELLE, LA JUSTICE ET L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS : LA MÉTAPHYSIQUE DE SES ORIGINES, SA LIBERTÉ DE CULTE, SES PHILOSOPHIES ET SES ESPOIRS. LE DESTIN ET LA VIE POUR VIVRE DES ACTES : UNE ORAISON VERS LA FLORAISON ? LES MÉCANISMES. TAY
LE DESTIN ET LA VIE AUQUEL LE COEUR D'UN CONCEPT S'EST EN IGNORER LA FIN LORSQUE L'ON S'APERÇOIT QU'UN NOUVEL HORIZON SE PROFIL DEPUIS LE DÉPART DE LA PALPITATION. LE TERME DE SIGNALER DANS L'HORIZON VERS LE VIVANT CORRESPOND AUX CIRCONSTANCES DU TEMPS. Y'BECCA EN JÉRUSALEM. TAY
L'HYPNOSE EST UN ART ET IL POSSÈDE LA FACULTÉ DE GUÉRIR DANS LA PLUPART DES DOMAINES MÉDICAUX. LA SAGESSE DE LA CONSCIENCE EST UNE OEUVRE AUQUEL NOUS SOMMES AU BORD D'UN GOUFFRE : À NOUS DE DÉFINIR SI ELLE EST UNE CAVERNE, UN SENTIMENT OU UN UNIVERS. TAY
DANS LE REJET DE LA VIE OU DE LA FIN DE VIE, IL Y A LONGTEMPS QUE LE SUJET FAIT PART DE SA SOLITUDE AU SOUFFLE. LE SILENCE SE PORTE AUX SAISONS TELS LES SOUPIRS QUI PEUPLENT LE TEMPS. L'HYPNOSE NE PEUT ENSEIGNER LA CERTITUDE CAR LA PEUR DEMEURE ENFOUIE : LE DESTIN ET LA VIE. TAY
LE CONSERVATISME NE SE MESURE PAS À L'ASPECT DE CROYANCE, DE PHILOSOPHIE OU DE TERME D'ÉLABORATION: IL EST DANS LE CADRE DU PATRIMOINE. LE CONSERVATISME NE SE MESURE PAS À L'ASPECT DE CROYANCE, DE PHILOSOPHIE OU DE TERME D'ÉLABORATION : IL EST DANS LE CADRE DU PATRIMOINE. TAY
TÉMOIGNAGE DE CITOYEN TIGNARD YANIS, PN 3286 de la Cour Européenne des droits de la femme, de l'enfant et de l'Homme, ALIAS TAY La chouette effraie, Y'BECCA EN JÉRUSALEM : les peuples dans le l'horizon, le vent et le verbe vers l'infini, le souffle et le vivant VERS L’ÉGIDE DE AMANDINE NIETZSCHERIMBAUD : Y'BECCA EN JÉRUSALEM ! Les peuples dans l'horizon vers l'infini  
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 Sujet: Re: KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS  
 
    KIRA, Y'BECCA, L'INFINI, LE MOUVEMENT, L'HORIZON ET LE TEMPS  

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