Virgo The Virgo Supercluster (Virgo SC) or Local Supercluster (LSC or LS) is the irregular supercluster that contains the Virgo Cluster in addition to the Local Group, which in turn contains the Milky Way and Andromeda galaxies. At least 100 galaxy groups and clusters are located within its diameter of 33 megaparsecs (110 million light-years). It is one of millions of superclusters in the observable universe. Background[edit] Beginning with the first large sample of nebulae published by William and John Herschel in 1863, it was known that there is a marked excess of nebular fields in the constellation Virgo (near the north galactic pole). Structure[edit] Galaxy distribution[edit] The number density of galaxies in the LS falls off with the square of the distance from its center near the Virgo Cluster, suggesting that this cluster is not randomly located. Cosmology[edit] Large scale dynamics[edit] Dark matter[edit] Maps[edit] Diagrams[edit] See also[edit] References[edit] External links[edit]
Satellite galaxy A satellite galaxy is a galaxy that orbits a larger galaxy due to gravitational attraction.[1] Although a galaxy is made of a large number of objects (such as stars, planets, and nebulae) that are not connected to each other, it has a center of mass, which represents a weighted average (by mass) of the positions of each component object. This is similar to how an everyday object has a center of mass which is the weighted average of the positions of all its component atoms.[1] Galaxies which encounter one another from certain directions may interact: collide, merge, rip each other apart, or transfer some member objects. In these situations, it can be difficult to tell where one galaxy ends and where another begins. Satellite galaxies of the Milky Way, our own galaxy. References[edit] See also[edit]
Supernova A supernova (abbreviated SN, plural SNe after "supernovae") is a stellar explosion that is more energetic than a nova. It is pronounced /ˌsuːpəˈnoʊvə/ with the plural supernovae /ˌsuːpəˈnoʊviː/ or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months. During this interval a supernova can radiate as much energy as the Sun is expected to emit over its entire life span.[1] The explosion expels much or all of a star's material[2] at a velocity of up to 30,000 km/s (10% of the speed of light), driving a shock wave[3] into the surrounding interstellar medium. This shock wave sweeps up an expanding shell of gas and dust called a supernova remnant. Nova means "new" in Latin, referring to what appears to be a very bright new star shining in the celestial sphere; the prefix "super-" distinguishes supernovae from ordinary novae which are far less luminous. Discovery[edit]
Cosmos Cosmos is the Universe regarded as an ordered system.[1] The philosopher Pythagoras is regarded as the first person to apply the term cosmos (Greek κόσμος) to the order of the Universe.[2] Cosmology[edit] Cosmology is the study of the cosmos in several of the above meanings, depending on context. All cosmologies have in common an attempt to understand the implicit order within the whole of being. In this way, most religions and philosophical systems have a cosmology. In physical cosmology, the term cosmos is often used in a technical way, referring to a particular spacetime continuum within the (postulated) multiverse. Theology[edit] In theology, the term can be used to denote the created Universe, not including the creator. See also[edit] References[edit] External links[edit]
Light-year The light-year is most often used when expressing distances to stars and other distances on a galactic scale, especially in non-specialist and popular science publications. The unit usually used in professional astrometry is the parsec (symbol: pc, approximately 3.26 light-years; the distance at which one astronomical unit subtends an angle of one second of arc).[1] Definitions[edit] As defined by the IAU, the light-year is the product of the Julian year[note 2] (365.25 days as opposed to the 365.2425-day Gregorian year) and the speed of light (299792458 m/s).[note 3] Both these values are included in the IAU (1976) System of Astronomical Constants, used since 1984.[3] From this the following conversions can be derived. Other high-precision values are not derived from a coherent IAU system. History[edit] The first successful measurement of the distance to a star other than our Sun was made by Friedrich Bessel in 1838. Distances in light-years[edit] Related units[edit] See also[edit]
Nebula Portion of the Carina nebula A nebula (from Latin: "cloud";[1] pl. nebulae or nebulæ, with ligature, or nebulas) is an interstellar cloud of dust, hydrogen, helium and other ionized gases. Originally, nebula was a name for any diffuse astronomical object, including galaxies beyond the Milky Way. Observational history The "Pillars of Creation" from the Eagle Nebula. On November 26, 1610, Nicolas-Claude Fabri de Peiresc discovered the Orion Nebula using a telescope. In 1715, Edmund Halley published a list of six nebulae.[8] This number steadily increased during the century, with Jean-Philippe de Cheseaux compiling a list of 20 (including eight not previously known) in 1746. The number of nebulae was then greatly expanded by the efforts of William Herschel and his sister Caroline Herschel. Formation The Triangulum Emission Garren Nebula NGC 604 Many nebulae or stars form from the gravitational collapse of gas in the interstellar medium or ISM. Other nebulae may form as planetary nebulae.
Andromeda–Milky Way collision The Andromeda–Milky Way collision is a galaxy collision predicted to occur in about 4 billion years between the two largest galaxies in the Local Group—the Milky Way (which contains our Solar System and Earth) and the Andromeda Galaxy.,[1][2][3] although the stars involved are sufficiently far apart that it is improbable that many of them will individually collide.[4] Stellar collisions[edit] While the Andromeda Galaxy contains about 1 trillion (1012) stars and the Milky Way contains about 300 billion (3×1011), the chance of even two stars colliding is negligible because of the huge distances between the stars. For example, the nearest star to the Sun is Proxima Centauri, about 4.2 light-years (4.0×1013 km; 2.5×1013 mi) or 30 million (3×107) solar diameters away. Black hole collisions[edit] Certainty[edit] These studies also suggest that M33, the Triangulum Galaxy – the third largest and brightest galaxy of the Local Group – will participate in this event. Merger remnant[edit]
Star For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space. Once the hydrogen in the core of a star is nearly exhausted, almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the star's lifetime and, for some stars, by supernova nucleosynthesis when it explodes. Near the end of its life, a star can also contain degenerate matter. Astronomers can determine the mass, age, metallicity (chemical composition), and many other properties of a star by observing its motion through space, luminosity, and spectrum respectively. The total mass of a star is the principal determinant of its evolution and eventual fate. A star's life begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements.
Sons et lumières Like many, you enjoy the fireworks ... but have you ever admired the colors in mind, and only the colors ???? They amaze and dazzle, with hidden effects, from “color symbols”. And if these fireworks unite so many people at nightfall, is that the colors they emit left us all stunned… small or large. We are amazed by the magic of chemistry, first. Manufacturing processes which are obviously far from thinking of when you push “oh !” This shows us once again that the colors are related to the welfare, a way : those that relax, those that encourage and / or facilitate reflection. Indeed, each of them produces a condition for both our mental state and physical fitness. There are different color schemes that can act on your emotions like on your body so favorable, that is able to provide you with form, serenity and tranquility. The relaxing colors are blue and its variations chromatic, who prefer the peace and contemplation in a bedroom, to relieve stress and tensions during the day. Principle ?
Quantum mechanics Description of physical properties at the atomic and subatomic scale Quantum mechanics is a fundamental theory in physics that describes the behavior of nature at and below the scale of atoms.[2]: 1.1 It is the foundation of all quantum physics including quantum chemistry, quantum field theory, quantum technology, and quantum information science. Classical physics, the collection of theories that existed before the advent of quantum mechanics, describes many aspects of nature at an ordinary (macroscopic) scale, but is not sufficient for describing them at small (atomic and subatomic) scales. Most theories in classical physics can be derived from quantum mechanics as an approximation valid at large (macroscopic) scale.[3] Overview and fundamental concepts Quantum mechanics allows the calculation of properties and behaviour of physical systems. A fundamental feature of the theory is that it usually cannot predict with certainty what will happen, but only give probabilities. . and , where Here
Observable Universe The surface of last scattering is the collection of points in space at the exact distance that photons from the time of photon decoupling just reach us today. These are the photons we detect today as cosmic microwave background radiation (CMBR). However, with future technology, it may be possible to observe the still older neutrino background, or even more distant events via gravitational waves (which also should move at the speed of light). Sometimes astrophysicists distinguish between the visible universe, which includes only signals emitted since recombination—and the observable universe, which includes signals since the beginning of the cosmological expansion (the Big Bang in traditional cosmology, the end of the inflationary epoch in modern cosmology). The universe versus the observable universe[edit] If the universe is finite but unbounded, it is also possible that the universe is smaller than the observable universe. Size[edit] Misconceptions[edit] 13.8 billion light-years
Draco Dwarf Characteristics[edit] Paul W. Hodge analyzed the distribution of its stars in 1964 and concluded that its ellipticity was 0.29 ± 0.04.[6] Recent studies have indicated that the galaxy may potentially hold large amounts of dark matter.[7] Having an absolute magnitude of -8.6[c] and a total luminosity of only 2×105 L☉, it is one of the faintest companions to our Milky Way.[4] Draco Dwarf contains many red giant branch (RGB) stars; five carbon stars have been identified in Draco Dwarf and four likely asymptotic giant branch (AGB) stars have been detected.[4] The Draco Dwarf is estimated to be about 80 ± 10 kpc[2][3] from earth and span a distance of 830 ± 100 × 570 ± 70 pc. RR Lyrae[edit] In 1961, Walter Baade and Henrietta H. [edit] Dark matter[edit] Recently, dwarf spheroidal galaxies have become key objects for the study of dark matter. At large radii, radial velocity dispersion exhibit strange behavior. Notes[edit] References[edit] External links[edit] Coordinates: 17h 20m 12.4s, +57° 54′ 55″
Solar System Discovery and exploration Andreas Cellarius's illustration of the Copernican system, from the Harmonia Macrocosmica (1660) For many thousands of years, humanity, with a few notable exceptions, did not recognize the existence of the Solar System. Structure and composition The orbits of the bodies in the Solar System to scale (clockwise from top left) The principal component of the Solar System is the Sun, a G2 main-sequence star that contains 99.86% of the system's known mass and dominates it gravitationally.[13] The Sun's four largest orbiting bodies, the gas giants, account for 99% of the remaining mass, with Jupiter and Saturn together comprising more than 90%. Most large objects in orbit around the Sun lie near the plane of Earth's orbit, known as the ecliptic. The overall structure of the charted regions of the Solar System consists of the Sun, four relatively small inner planets surrounded by a belt of rocky asteroids, and four gas giants surrounded by the Kuiper belt of icy objects.
Colour Music