An other earth in our galaxy?? It's possible??
NASA discovered this..
The next video provr that.
The core of the sun: It's magic
The core of sun The core of the Sun is considered to extend from the center to about 20–25% of the solar radius. It has a150 g/cm3 (about 150 times the density of water) and a temperature of close to 15.7 million kelvin (K).
Jupiter: The 5th palnet
upiter is the fifth planet from the Sun and the largest planet in the Solar System. It is a gas giant with mass one-thousandth of that of the Sun but is two and a half times the mass of all the other planets in the Solar System combined. Jupiter is classified as a gas giant along with Saturn, Uranus and Neptune.
The Earth ... Our fantastic planet
Earth, also known as the world, Terra, or Gaia, is the third planet from the Sun, the densest planet in the Solar System, the largest of the Solar System's four terrestrial planets
The magic Hubble Space Telescope
The Hubble Space Telescope (HST) is a space telescope that was launched into low Earth orbit in 1990near ultraviolet, visible, and near infrared spectra. The telescope is named after the astronomer Edwin Hubble. and remains in operation.
NASA Telescopes Uncover Early Construction of Giant Galaxy
Astronomers have for the first time caught a glimpse of the earliest stages of massive galaxy construction. The building site
Wednesday, September 10, 2014
The core of the sun: It's magic
The core of sun
The core of the Sun is considered to extend from the center to about 20–25% of the solar radius. It has a150 g/cm3 (about 150 times the density of water) and a temperature of close to 15.7 million kelvin (K). By contrast, the Sun's surface temperature is approximately 5,800 K. Recent analysis of SOHO mission data favors a faster rotation rate in the core than in the rest of the radiative zone. Through most of the Sun's life, energy is produced by nuclear fusion through a series of steps called the p–p (proton–proton) chain; this process converts hydrogen into helium. Only 0.8% of the energy generated in the Sun comes from the CNO cycle.
density of up to
The core is the only region in the Sun that produces an appreciable
amount of thermal energy through fusion; 99% of the power is generated
within 24% of the Sun's radius, and by 30% of the radius, fusion has
stopped nearly entirely. The rest of the star is heated by energy that
is transferred outward by radiation from the core to the convective
layers just outside. The energy produced by fusion in the core must then
travel through many successive layers to the solar photosphere before
it escapes into space as sunlight or the kinetic energy of particles.
The proton–proton chain occurs around 9.2×1037 times each second in the core. Since this reaction uses four free protons (hydrogen nuclei), it converts about 3.7×1038 protons to alpha particles (helium nuclei) every second (out of a total of ~8.9×1056 free protons in the Sun), or about 6.2×1011 kg per second.[18] Since fusing hydrogen into helium releases around 0.7% of the fused mass as energy,[54] the Sun releases energy at the mass–energy conversion rate of 4.26 million metric tons per second, 384.6 yotta watts (3.846×1026 W),[1] or 9.192×1010 megatons of TNT per second.
The power production by fusion in the core varies with distance from
the solar center. At the center of the Sun, theoretical models estimate
it to be approximately 276.5 watts/m3,[55] a power production density that more nearly approximates reptile metabolism than a thermonuclear bomb.[d] Peak power production in the Sun has been compared to the volumetric heats generated in an active compost heap. The tremendous power output of the Sun is not due to its high power per volume, but instead due to its large size.
The fusion rate in the core is in a self-correcting equilibrium: a
slightly higher rate of fusion would cause the core to heat up more and expand slightly against the weight of the outer layers, reducing the fusion rate and correcting the perturbation;
and a slightly lower rate would cause the core to cool and shrink
slightly, increasing the fusion rate and again reverting it to its
present level.[56][57]
The gamma rays
(high-energy photons) released in fusion reactions are absorbed in only
a few millimeters of solar plasma and then re-emitted again in a random
direction and at slightly lower energy. Therefore it takes a long time
for radiation to reach the Sun's surface. Estimates of the photon travel
time range between 10,000 and 170,000 years.[58] In contrast, it takes only 2.3 seconds for the neutrinos,
which account for about 2% of the total energy production of the Sun,
to reach the surface. Since energy transport in the Sun is a process
which involves photons in thermodynamic equilibrium with matter, the
time scale of energy transport in the Sun is longer, on the order of
30,000,000 years. This is the time it would take the Sun to return to a
stable state if the rate of energy generation in its core were suddenly
to be changed.[59]
During the final part of the photon's trip out of the Sun, in the
convective outer layer, collisions are fewer and far between, and they
have less energy. The photosphere is the transparent surface of the Sun
where the photons escape as visible light. Each gamma ray in the Sun's core is converted into several million photons of visible light before escaping into space. Neutrinos
are also released by the fusion reactions in the core, but unlike
photons they rarely interact with matter, so almost all are able to
escape the Sun immediately. For many years measurements of the number of
neutrinos produced in the Sun were lower than theories predicted by a factor of 3. This discrepancy was resolved in 2001 through the discovery of the effects of neutrino oscillation: the Sun emits the number of neutrinos predicted by the theory, but neutrino detectors were missing 2⁄3 of them because the neutrinos had changed flavor by the time they were detected
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The magic black Hole (Video)
See the black hole on video... it's magic and danger dream
Let' see the video tougether
From Youtube
Let' see the video tougether
From Youtube
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Natural satellite of our solar system
A natural satellite, or moon, is a celestial body that orbits another body, e.g. a planet, which is called its . There are 173 known natural satellites orbiting planets in the Solar System, as well as at least eight orbiting IAU-listed dwarf planets. As of January 2012, over 200 minor-planet moons have been discovered.[4] There are 76 known objects in the asteroid belt with satellites (five with two satellites each), four Jupiter trojans, 39 near-Earth objects (two with two satellites each), and 14 Mars-crossers. There are also 84 known natural satellites of trans-Neptunian objects. Some 150 additional small bodies have been observed within rings of Saturn,
but only a few were tracked long enough to establish orbits. Planets
around other stars are likely to have satellites as well, though
numerous candidates have been detected to date, none have yet been
confirmed.
primary
Of the inner planets, Mercury and Venus have no natural satellites; Earth has one large natural satellite, known as the Moon; and Mars has two tiny natural satellites, Phobos and Deimos. The large gas giants have extensive systems of natural satellites, including half a dozen comparable in size to Earth's Moon: the four Galilean moons, Saturn's Titan, and Neptune's Triton. Saturn has an additional six mid-sized natural satellites massive enough to have achieved hydrostatic equilibrium, and Uranus has five. It has been suggested that some satellites may potentially harbour life, though there is currently no direct evidence of life.
The Earth–Moon system is unique in that the ratio of the mass of the
Moon to the mass of the Earth is much greater than that of any other
natural-satellite–planet ratio in the Solar System (although there are minor-planet systems with even greater ratios, notably the Pluto–Charon system).
Among the dwarf planets, Ceres and Makemake have no known natural satellites. Pluto has the relatively large natural satellite Charon and four smaller natural satellites. Haumea has two natural satellites, and Eris has one. The Pluto–Charon system is unusual in that the center of mass lies in open space between the two, a characteristic sometimes associated with a double-planet system.
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Mercury: The first and nearly planet to sun
Mercury is the smallest and closest to the Sun of the eight planets in the Solar System, with an orbital period Earth days. Seen from Earth, it appears to move around its orbit in about 116 days, which is much faster than any other planet. It has no known natural satellites. The planet is named after the Roman deity Mercury, the messenger to the gods.
of about 88
Because it has almost no atmosphere to retain heat, Mercury's surface
experiences the greatest temperature variation of all the planets,
ranging from 100 K (−173 °C; −280 °F) at night to 700 K (427 °C; 800 °F)
during the day at some equatorial regions. The poles are constantly
below 180 K (−93 °C; −136 °F). Mercury's axis has the smallest tilt of any of the Solar System's planets (about 1⁄30 of a degree), but it has the largest orbital eccentricity.[a] As such it does not experience seasons in the same way as most other planets such as Earth. At aphelion, Mercury is about 1.5 times as far from the Sun as it is at perihelion. Mercury's surface is heavily cratered and similar in appearance to the Moon, indicating that it has been geologically inactive for billions of years.
Mercury is gravitationally locked and rotates in a way that is unique in the Solar System. As seen relative to the fixed stars, it rotates exactly three times for every two revolutions[c] it makes around its orbit.[13] As seen from the Sun, in a frame of reference
that rotates with the orbital motion, it appears to rotate only once
every two Mercurian years. An observer on Mercury would therefore see
only one day every two years.
Because Mercury moves in an orbit around the Sun which lies within Earth's orbit (as does Venus),
it can appear in Earth's sky in the morning or the evening, but not in
the middle of the night. Also, like Venus and the Moon, it displays a
complete range of phases
as it moves around its orbit relative to Earth. Although Mercury can
appear as a bright object when viewed from Earth, its proximity to the
Sun makes it more difficult to see than Venus. Two spacecraft have
visited Mercury: Mariner 10 flew by in the 1970s and MESSENGER, launched in 2004, remains in orbit.
Mercury planet
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Venus: The 2nd planet solar system
Venus is the second planet from the Sun, orbiting it every 224.7 Earth days. It has no natural satellite. It isRoman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows. Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°.
Venus is a terrestrial planet
and is sometimes called Earth's "sister planet" because of their
similar size, gravity, and bulk composition (Venus is both the closest
planet to Earth and the planet closest in size to Earth). However, it
has also been shown to be radically different from Earth in other
respects. It has the densest atmosphere of the four terrestrial planets, consisting of more than 96% carbon dioxide. The atmospheric pressure
at the planet's surface is 92 times that of Earth's. With a mean
surface temperature of 735 K (462 °C; 863 °F), Venus is by far the
hottest planet in the Solar System. It has no carbon cycle
to lock carbon back into rocks and surface features, nor does it seem
to have any organic life to absorb it in biomass. Venus is shrouded by
an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light. Venus may have possessed oceans in the past,[13][14] but these would have vaporized as the temperature rose due to a runaway greenhouse effect. The water has most probably photodissociated, and, because of the lack of a planetary magnetic field, the free hydrogen has been swept into interplanetary space by the solar wind. Venus's surface is a dry desertscape interspersed with slab-like rocks and periodically refreshed by volcanism.
Venus
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Mars, the 4th planet of the solar system
Mars (The 4th planet) is the fourth planet from the Sun and the second smallest planet in the Solar System, after .Roman god of war, it is often described as the "Red Planet" because the iron oxide prevalent on its surface gives it a reddish appearance. Mars is a terrestrial planet with a thin atmosphere, having surface features reminiscent both of the impact craters of the Moon and the volcanoes, valleys, deserts, and polar ice caps of Earth. The rotational period
and seasonal cycles of Mars are likewise similar to those of Earth, as
is the tilt that produces the seasons. Mars is the site of Olympus Mons, the second highest known mountain within the Solar System (the tallest on a planet), and of Valles Marineris, one of the largest canyons. The smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature. Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Martian trojan asteroid.
MercuryNamed after the
Until the first successful Mars flyby in 1965 by Mariner 4,
many speculated about the presence of liquid water on the planet's
surface. This was based on observed periodic variations in light and
dark patches, particularly in the polar latitudes, which appeared to be seas and continents; long, dark striations were interpreted by some as irrigation channels for liquid water. These straight line features were later explained as optical illusions,
though geological evidence gathered by unmanned missions suggests that
Mars once had large-scale water coverage on its surface at some earlier
stage of its life. In 2005, radar data revealed the presence of large quantities of water ice at the poles and at mid-latitudes. The Mars rover Spirit sampled chemical compounds containing water molecules in March 2007. The Phoenix lander directly sampled water ice in shallow Martian soil on July 31, 2008.
Mars is host to five functioning spacecraft: three in orbit – the Mars Odyssey, Mars Express, and Mars Reconnaissance Orbiter – and two on the surface – Mars Exploration Rover Opportunity and the Mars Science Laboratory Curiosity. Defunct spacecraft on the surface include MER-A Spirit and several other inert landers and rovers such as the Phoenix lander, which completed its mission in 2008. Observations by the Mars Reconnaissance Orbiter have revealed possible flowing water during the warmest months on Mars.[25]
In 2013, NASA's Curiosity rover discovered that Mars' soil contains
between 1.5% and 3% water by mass (about two pints of water per cubic
foot or 33 liters per cubic meter, albeit attached to other compounds
and thus not freely accessible).
Mars can easily be seen from Earth with the naked eye, as can its reddish coloring. Its apparent magnitude reaches −3.0,[8] which is surpassed only by Jupiter, Venus,
the Moon, and the Sun. Optical ground-based telescopes are typically
limited to resolving features about 300 km (186 miles) across when Earth
and Mars are closest because of Earth's atmosphere.
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ESA Ministerial in Doubt as France, Germany Remain Far Apart on Future Launcher
PARIS — The French and German
governments remain so far apart on a future space-launch policy for
Europe that officials are now privately talking about canceling a
December conference of European space ministers or stripping it of
concrete decisions.
The basic division remains despite the German government’s alignment
with the French view that Europe needs a lower-cost rocket to maintain
its viability in the commercial market — which in turn provides European
governments with a viable launch industry.
Despite the consensus over the longer term, the two sides remain
split on whether European Space Agency governments should spend 1.2
billion euros ($1.6 billion) to complete work on a new upper stage for
the existing Ariane 5 rocket, which could fly in 2018-2019, or abandon
the upgrade to focus spending on a new Ariane 6 rocket, whose
development would cost upwards of 3 billion euros over 7-8 years.
Each side has its arguments.
Germany says completing the Ariane 5 ME vehicle, with a more powerful
and restartable upper stage, would give the Arianespace launch
consortium a superior weapon in the commercial market before the end of
the decade.
The problem: Ariane 5 ME likely will cost as much to launch as the
current Ariane 5 ECA rocket, or around 140 million euros, thus requiring
continued ESA cash injections of around 100 million euros per year to
balance Arianespace’s books.
The French argument is that the Ariane 5 ME money could be better
spent on Ariane 6, especially if there is a consensus that this rocket
should be in service around 2022.
ESA and the French space agency, CNES, have been working on an Ariane
6 design since the last ESA ministerial conference in November 2012.
But this design, with two solid-propellant stages topped by a cryogenic
stage, faced criticism from the commercial market and from Germany,
which said its industry would not have much of a place in the rocket’s
construction.
A mid-June proposal by Ariane 5 prime contractor Airbus Defence and
Space and rocket motor maker Safran, celebrated by French President
Francois Hollande, provided the final blow to the ESA design, officials
said.
The current Ariane 6 design being considered is a solid-fueled first
stage with cryogenic second and third stages, bolstered by one or two
pairs of solid-fueled strap-on boosters.
The Airbus-Safran proposal says this vehicle could be built and
launched for 80 million euros assuming 10 launches per year. For lighter
payloads of the sort often launched by European governments, the core
vehicle would use two strap-on boosters in a version called Ariane 62.
A heavier Ariane 64 variant would be used to orbit commercial
payloads weighing up to 11,000 kilograms. The core would be augmented
with four of the same strap-on boosters, each carrying 120,000 kilograms
of solid propellant.
ESA and its principal member states have agreed that whatever
solution is selected, the agency’s total annual spending on launch
vehicles — including the Vega small-satellite launcher and any costs
associated with Ariane 5 operations — should not exceed 800 million
euros per year.
Ariane 5 ME and Ariane 6 cannot both be fitted into this spending corridor; ESA governments must delay or cancel one of them.
Ariane 5 ME supporters say they believe they can cut the vehicle’s
recurring launch cost by 10 percent, enough to make its operations on
the commercial market more profitable and to do away with the annual
government support payments. The vehicle’s skeptics doubt whether this
will be the case.
Ariane 6 skeptics say the 80 million-euro cost per launch, assuming
10 launches per year, will be a stretch for the industrial team. And 80
million euros is already more than the 70 million-euro target that ESA
and CNES, had set for their earlier Ariane 6 design.
Many European government officials, at ESA and at the national space
agencies, notably in France and Germany, agreed to forgo their summer
vacations to meet weekly to find a solution. They met again Sept. 4 and
will reconvene with an important date of Sept. 17.
Several European space ministers will meet Sept. 23 in Zurich to
determine whether there is hope for a common policy in time for the
ministerial conference set for Dec. 2 in Luxembourg. If the answer is
no, they will have the option of canceling the Dec. 2 meeting, or
maintaining the date but limiting the conference to a general statement
about Europe’s future launch-vehicle policy, with costs, dates and
design details to be decided later.
As has been the case for a year, discussion in Europe about
continuing as a partner with the United States on the international
space station to 2020 and beyond has been put on ice pending a decision
on launcher policy.
Othor: Peter B. de Selding
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The Black hole, the mesterious of space
A black hole is a region of spacetime from which gravity prevents anything, including light, from[1] The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole.[2] The boundary of the region from which no escape is possible is called the event horizon.
Although crossing the event horizon has enormous effect on the fate of
the object crossing it, it appears to have no locally detectable
features. In many ways a black hole acts like an ideal black body, as it reflects no light.[3][4] Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum
as a black body of a temperature inversely proportional to its mass.
This temperature is on the order of billionths of a Kelvin for black holes of stellar mass, making it all but impossible to observe.
escaping.
Objects whose gravitational fields are too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace. The first modern solution of general relativity that would characterize a black hole was found by Karl Schwarzschild in 1916, although its interpretation as a region of space from which nothing can escape was first published by David Finkelstein
in 1958. Long considered a mathematical curiosity, it was during the
1960s that theoretical work showed black holes were a generic prediction
of general relativity. The discovery of neutron stars sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality.
Black holes of stellar mass are expected to form when very massive
stars collapse at the end of their life cycle. After a black hole has
formed it can continue to grow by absorbing mass from its surroundings.
By absorbing other stars and merging with other black holes, supermassive black holes of millions of solar masses may form. There is general consensus that supermassive black holes exist in the centers of most galaxies.
Despite its invisible interior, the presence of a black hole can be inferred through its interaction with other matter and with electromagnetic radiation such as light. Matter falling onto a black hole can form an accretion disk heated by friction, forming some of the brightest objects in the universe.
If there are other stars orbiting a black hole, their orbit can be used
to determine its mass and location. Such observations can be used to
exclude possible alternatives (such as neutron stars). In this way,
astronomers have identified numerous stellar black hole candidates in binary systems, and established that the core of the Milky Way contains a supermassive black hole of about 4.3 million solar masses.
Video from youtube
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The Sun: Our first star
The Sun formed about 4.567 billion[a][16] years ago from the gravitational collapse of a region within a large molecular cloud. Most of the matter gathered in the center, while the rest flattened into an orbiting disk that would become the Solar System. The central mass became increasingly hot and dense, eventually initiating thermonuclear fusion in its core. It is thought that almost all stars form by this process. The Sun is a G-type main-sequence star (G2V) based on spectral class and it is informally designated as a yellow dwarf because its visible radiation is most intense in the yellow-green portion of the spectrum, and although it is actually white in color, from the surface of the Earth it may appear yellow because of atmospheric scattering of blue light.[17] In the spectral class label, G2 indicates its surface temperature, of approximately 5778 K (5505 °C, 9941 °F), and V indicates that the Sun, like most stars, is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses about 620 million metric tons of hydrogen each second.[18][19]
Once regarded by astronomers as a small and relatively insignificant
star, the Sun is now thought to be brighter than about 85% of the stars
in the Milky Way, most of which are red dwarfs.[20][21] The absolute magnitude of the Sun is +4.83; however, as the star closest to Earth, the Sun is by far the brightest object in the sky with an apparent magnitude of −26.74.[22][23] This is about 13 billion times brighter than the next brightest star, Sirius, with an apparent magnitude of −1.46. The Sun's hot corona continuously expands in space creating the solar wind, a stream of charged particles that extends to the heliopause at roughly 100 astronomical units. The bubble in the interstellar medium formed by the solar wind, the heliosphere, is the largest continuous structure in the Solar System.[24][25]
The Sun is currently traveling through the Local Interstellar Cloud (near to the G-cloud) in the Local Bubble zone, within the inner rim of the Orion Arm of the Milky Way. Of the 50 nearest stellar systems within 17 light-years from Earth (the closest being a red dwarf named Proxima Centauri at approximately 4.2 light-years away), the Sun ranks fourth in mass. The Sun orbits the center of the Milky Way at a distance of approximately 24000–26000 light-years from the galactic center, completing one clockwise orbit, as viewed from the galactic north pole, in about 225–250 million years. Since the Milky Way is moving with respect to the cosmic microwave background radiation (CMB) in the direction of the constellation Hydra with a speed of 550 km/s, the Sun's resultant velocity with respect to the CMB is about 370 km/s in the direction of Crater or Leo.
The mean distance of the Sun from the Earth is approximately 1 astronomical unit (about 150,000,000 km; 93,000,000 mi), though the distance varies as the Earth moves from perihelion in January to aphelion in July. At this average distance, light travels from the Sun to Earth in about 8 minutes and 19 seconds. The energy of this sunlight supports almost all life[b] on Earth by photosynthesis,[31] and drives Earth's climate and weather. The enormous effect of the Sun on the Earth has been recognized since prehistoric times, and the Sun has been regarded by some cultures as a deity.
An accurate scientific understanding of the Sun developed slowly, and
as recently as the 19th century prominent scientists had little
knowledge of the Sun's physical composition and source of energy. This
understanding is still developing; there are a number of present-day anomalies in the Sun's behavior that remain unexplained.
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