WONDERS OF THE SOLAR SYSTEM PDF

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Wonders of the Solar System is a planetarium program that explores the sizes, distances, and amazing natural features of the nine known planets, many of the. This graphic of the solar system was made using real images of the planets and Cover Images: Solar System: NASA/JPL; YSS logo: NASA; Sun: Venus energy present, it is no wonder astrobiologists think Europa could be a habitat for . In Wonders of the Solar System – the book of the acclai The graph on page 5 of the pdf shows that the sun's energy output fluctuates with a roughly year.


Wonders Of The Solar System Pdf

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Visit muscpertastsunear.tk to find events near you. is the hottest planet in our Solar System, with an average temperature of °C. The surface. This BBC Focus Special Edition reveals the wonders of the Solar System and the latest missions to explore new frontiers IN THIS ISSUE. Wonders of the Universe Professor Brian Cox & Andrew Cohen .. The distance between the Sun and the outermost planet of our solar system, Neptune.

Amun can be seen as the hidden aspect of the Sun, sometimes associated with his voyage through the Underworld during the night.

Worship of Amun-Re as the supreme god became so widespread that the Egyptian religion became almost monotheistic during the New Kingdom. Amun-Re was said to exist in all things, and it was believed that he transcended the boundaries of space and time to be all-seeing and eternal. In this sense, he could be seen as a precursor to the gods of the Judeo-Christian and Islamic traditions. The walls of Karnak Temple are literally covered with representations of Amun-Re, usually depicted in human form with a double-plumed crown of feathers — the precise meaning of which is unknown.

He is most often seen with the Pharaoh, but he also appears at Karnak in animal form, as a ram. The Great Hypostyle Hall, the dominant feature of the temple, is aligned such that on 21 December, the winter solstice and shortest day in the Northern Hemisphere, the disc of the Sun rises between the great pillars and floods the space with light, which comes from a position directly over a small building inside which Amun-Re himself was thought to reside.

Standing beside the towering stone columns watching the solstice sunrise is a powerful experience. It connects you directly with the names of the great pharaohs of ancient Egypt, because Amenophis III, Tutankhamen and Rameses II would have stood there to greet the rising December sun over three millennia ago.

As Earth moves around the Sun, the North Pole gradually tilts towards the Sun and the Sun takes a higher daily arc across the sky until midsummer, when it reaches its highest point. This gradual tilting back and forth throughout the year means that the point at which the Sun rises on the eastern horizon also moves each day. If you stand facing east, the most southerly rising point occurs at the winter solstice. The sunrise then gradually drifts northwards until it reaches its most northerly point at the summer solstice.

The solstices would have been unique times of year and important for a civilisation that revered the Sun as a god. Standing in Karnak Temple watching the sunrise on this special midwinter day the alignment is obvious, but proving that ancient sites are aligned with events in the sky is difficult and controversial. This is because a temple the size of Karnak will always be aligned with something in the sky, simply because it has buildings that point in all directions!

These columns are delicately carved, and it is the inscriptions that suggest the sunrise alignment is deliberate. The left-hand column has an image of the Pharaoh embracing Amun-Re, and on one face are three carved papyrus stems — a plant that only grows along the northern reaches of the Nile. The right-hand column is similar in design, except the Pharaoh embraces Amun-Re wearing the crown of upper Egypt, which is south of Karnak.

The three carved stems on this column are lotus blossoms, which only grow to the south. It seems clear therefore that the columns are positioned and decorated to mark the compass directions around the temple, which is persuasive evidence that the heart of this building is aligned to capture the light from an important celestial event — the rising of the Sun in midwinter. The temple represents the fascination of the ancient Egyptians with the movement of the lights they saw in the sky. Their instinct to venerate them was pre-scientific, but the building also appears to enshrine a deepening awareness of the geometry of the cosmos.

The development of more advanced agricultural techniques made civilisations more prosperous, ultimately giving them more time for thought, philosophy, mathematics and science. So astronomy began a virtuous cycle through which the quest to understand the heavens and their meaning lead to practical and intellectual riches beyond the imagination of the ancients. The step from observing the regularity in the movement of the heavenly lights to modern science took much of recorded human history.

The ancient Greeks began the work, but the correct description of the motion of the Sun, Moon and planets across the sky was discovered in the seventeenth century by Johannes Kepler. Removing the veil of the divine to reveal the true beauty of the cosmos was a difficult process, but the rewards that stem from that innate human fascination with the lights in the sky have proved to be incalculable By following the light we have mapped our place among the hundreds of billions of stars that make up the Milky Way Galaxy.

We have visited our nearest star, Proxima Centauri, and measured its chemical compositions, and those of thousands of other stars in the sky. We have even journeyed deep into the Milky Way and stared into the black hole that lies at the centre of our galactic home. But this is just the beginning… The Universe is an awe-inspiring place, full of wonder and demanding the answers to so many questions. We have so much to learn and so many places to explore. As we have discovered the grand cycles that play out above our heads we have come to realise that we are part of a structure that extends way beyond our solar system and the billion stars that make up our galaxy.

Our nearest star, the Sun, is million kilometres 93 million miles away, but each night when this star disappears from view, thousands more fill the night sky. In the most privileged places on Earth, up to 10, stars can be seen with the naked eye, and all of them are part of the galaxy we call home. A galaxy is a massive collection of stars, gas and dust bound together by gravity. It is a place where stars live and die, where the life cycles of our universe are played out on a gargantuan scale.

We think there are around billion galaxies in the observable universe, each containing many millions of stars. The smallest galaxies, known as dwarf galaxies, have as few as ten million stars. The biggest, the giants, have been estimated to contain in the region of trillion. It is now widely accepted that galaxies also contain much more than just the matter we can see using our telescopes. They are thought to have giant halos of dark matter, a new form of matter unlike anything we have discovered on Earth and which interacts only weakly with normal matter.

Despite this, its gravitational effect dominates the behaviour of galaxies today and most likely dominated the formation of the galaxies in the early Universe. This is because we now think that around 95 per cent of the mass of galaxies such as our own Milky Way is made up of dark matter.

The search for the nature of dark matter is one of the great challenges for twenty-first-century physics. We shall return to the fascinating subject of dark matter later in the book.

It was first used to describe the galaxy that dominates our night skies, even though the Greeks could have had no concept of its true scale. For many people it looks like the rising of storm clouds on the horizon, but as the Earth turns nightly towards the centre of our galaxy, the hazy band of light reveals itself as clouds of stars — billions of them stretching thousands of light years inwards towards the galactic centre.

This story is the origin of the modern name for our galaxy — the Milky Way. In this image the central jet is visible, which is a powerful beam of hot gas produced by a massive black hole in the core of the galaxy. It is our largest and closest spiral galaxy, and in this picture we can clearly see rings of new star formations developing. The spiral shape of the galaxy is immediately obvious, with curving arms of pinky-red, star-forming regions and blue star clusters.

However, recent Hubble Space Telescope images have identified older stars within it, making the galaxy as old as others but with new star formations. The majority of stars lie in a disc around , light years in diameter and, on average, around 1, light years thick. These vast distances are very difficult to visualise.

A Visual Exploration of All the Planets, Moons and Other Heavenly Bodies that Orbit Our Sun

A distance of , light years means that light itself, travelling at , kilometres , miles per second, would take , years to make a journey across our galaxy. You would have to lay around million solar systems end to end to cross our galaxy. At the centre of our galaxy, and possibly every galaxy in the Universe, there is believed to be a super-massive black hole. Astronomers believe this because of precise measurements of the orbit of a star known as S2.

The only known way of cramming 4. Beyond the S-stars, the galactic centre is a melting pot of celestial activity, filled with all sorts of different systems that interact and influence each other. The Arches Cluster is the densest known star cluster in the galaxy. Formed from about young, intensely hot stars that dwarf our sun in size, these stars burn brightly and are consequently very short-lived, exhausting their supply of hydrogen in just a couple of million years.

The Quintuplet Cluster contains one of the most luminous stars in our galaxy, the Pistol Star, which is thought to be near the end of its life and on the verge of becoming a supernova see Chapter 2.

It is in central clusters like the Arches and the Quintuplet that the greatest density of stars in our galaxy can be found. As we move out from the crowded galactic centre, the number of stars drops with distance, until we reach the sparse cloud of gas in the outer reaches of the Milky Way known as the Galactic Halo. HE is a star in the last stages of its life; known as a red giant, it is a vast structure far bigger than our sun, but much cooler at its surface.

HE is interesting because astronomers have been able to measure the precise quantities of five radioactive elements — uranium, thorium, europium, osmium and iridium — in the star. Using a technique very similar to carbon dating a method archaeologists use to measure the age of organic material on Earth , astronomers have been able to get a precise age for this ancient star. This is why the detection of five radioactive elements in the light from HE was so important.

This dying star turns out to be Known as a barred spiral galaxy, it consists of a bar-shaped core surrounded by a disc of gas, dust and stars that creates individual spiral arms twisting out from the centre.

Until very recently, it was thought that our galaxy contained only four spiral arms — Perseus, Norma, Scutum—Centaurus and Carina—Sagittarius, with our sun in an off shoot of the latter called the Orion spur — but there is now thought to be an additional arm, called the Outer arm, an extension to the Norma arm.

Close to the inner rim of the Orion spur is the most familiar star in our galaxy. The Sun was once thought to be an average star, but we now know that it shines brighter than 95 per cent of all other stars in the Milky Way. Every second, the Sun burns million tonnes of hydrogen in its core, producing million tonnes of helium in the fusion reaction. Located 5, light years away, the Lagoon Nebula is one of a handful of active star-forming regions in our galaxy that are visible from Earth with the naked eye.

Roughly once a year a new light appears in our galaxy, as somewhere in the Milky Way a new star is born. The Lagoon Nebula is one such star nursery; within this giant interstellar cloud of gas and dust, new stars are created.

Discovered by French astronomer Guillaume Le Gentil in , this is one of a handful of active star-forming regions in our galaxy that are visible with the naked eye. This huge cloud is slowly collapsing under its own gravity, but slightly denser regions gradually accrete more and more matter, and over time these clumps grow massive enough to turn into stars. The centre of this vast stellar nursery, known as the Hourglass, is illuminated by an intriguing object known as Herschel Recent measurements suggest that Herschel 36 may actually be three large young stars orbiting around each other, with the entire system having a combined mass of over fifty times that of our sun.

This makes Herschel 36 a true system of giants. Eventually Herschel 36 and all the stars in the Milky Way will die, and when they do, many will go out in a blaze of glory.

Eta Carinae is a pair of billowing gas and dust clouds that are the remnants of a stellar explosion from an unstable star system. The system consists of at least two giant stars, and shines with a brightness four million times that of our sun. One of these stars is thought to be a Wolf-Rayet star.

These stars are immense, over twenty times the mass of our sun, and are engaged in a constant struggle to hang onto their outer layers, losing vast amounts of mass every second in a powerful solar wind. In , Eta Carinae became one of the brightest stars in the Universe when it exploded. The blast spat matter out at nearly 2.

Eta Carinae survived intact and remains buried deep inside these clouds, but its days are numbered. Because of its immense mass, the Wolf-Rayet star is using up its hydrogen fuel at a ferocious rate. Within a few hundred thousand years, it is expected that the star will explode in a supernova or even a hypernova the biggest explosion in the known Universe , although its fate may be sealed a lot sooner.

In , an explosion thought to be similar to the Eta Carinae event was seen in a galaxy over seventy million light years from the Milky Way. Just two years later, the star exploded as a supernova. Eta Carinae is very much closer — at a distance of only 7, light years — so as a supernova it may shine so brightly that it will be visible from Earth even in daylight.

Out in the Milky Way we can see the whole cycle of stellar life playing out. Roughly once a year a new light appears, as somewhere in the Milky Way a new star is born. Eta Carinae is one of the most massive and visible stars in the night sky, but because of its mass it is also the most volatile and most likely to explode in the near future.

NASA Seeing the light from these distant worlds and watching the life cycle of the Universe unfold is a breathtaking reminder that light is the ultimate messenger; carrying information about the wonders of the Universe to us across interstellar and intergalactic distances.

But light does much more than just allow us to see these distant worlds; it allows us to journey back through time, providing a direct and real connection with our past. This seemingly impossible state of affairs is made possible not only because of the information carried by the light, but by the properties of light itself Eventually all the stars in the Milky Way will die, many in spectacular explosions. Herschel 36 was formed from just such a stellar explosion, which occurred within the Eta Carinae system.

If we aspire to understand the world around us, one of the most basic questions we must ask is about the nature of light. It is the primary way in which we observe our own planet, and the only way we will ever be able to explore the Universe beyond our galaxy. For now, even the stars are far beyond our reach, and we rely on their light alone for information about them. By the seventeenth century, many renowned scientists were studying the properties of light in detail, and parallel advances in engineering and science both provided deep insights and catalysed each other.

The studies of Kepler, Galileo and Descartes, and some of the later true greats of physics — Huygens, Hooke and Newton — were all fuelled by the desire to build better lenses for microscopes and telescopes to enable them to explore the Universe on every scale, and to make great scientific discoveries and advances in the basic science itself.

There were some notable exceptions, including the great mathematician Leonhard Euler, who felt that the phenomena of diffraction could only be explained by a wave theory. In , the English doctor Thomas Young appeared to settle the matter once and for all when he reported the results from his famous double-slit experiment, which clearly showed that light diffracted, and therefore must travel in the form of a wave.

Diffraction is a fascinating and beautiful phenomena that is very difficult to explain without waves. Imagine two waves on top of each other with exactly the same wavelength and wave height technically known as the amplitude , but aligned precisely so that the peak of one wave lies directly on the trough of the other in more technical language, we say that the waves are degrees out of phase , and so the waves cancel each other out.

If these waves were light waves you would get darkness! This is exactly what is seen in diffraction experiments through small slits. The slits act like lots of little sources of light, all slightly displaced from one another.

This means that there will be places beyond the slits where the waves cancel each other out, and places where they will add up, leading to the light and dark areas seen by experimenters like Young. This was taken as clear evidence that light was some kind of wave — but waves of what? The experiment demonstrates the inseparability of the wave and particle natures of light and other quantum particles. In the mid-nineteenth century, the study of electricity and magnetism engaged many great scientific minds.

At the Royal Institution in London, Michael Faraday was busy doing what scientists do best — playing around with wire and magnets.

He discovered that if you push a magnet through a coil of wire, an electric current flows through the wire while the magnet is moving. This is a generator; the thing that sits in all power stations around the world today, providing us with electricity.

A single amp is defined as the current that must flow along two parallel wires of infinite length and negligible diameter to produce an attractive force of 0. By , a great deal was known about electricity and magnetism. Magnets could be used to make electric currents flow, and flowing electric currents could deflect compass needles in the same way that magnets could.

There was clearly a link between these two phenomena, but nobody had come up with a unified description. Electricity and magnetism can be unified by introducing two new concepts: electric and magnetic fields. The idea of a field is central to modern physics; a simple example of something that can be represented by a field is the temperature in a room.

If you could measure the temperature at each point in the room and note it down, eventually you would have a vast array of numbers that described how the temperature changes from the door to the windows and from the floor to the ceiling. This array of numbers is called the temperature field. In a similar way, you could introduce the concept of a magnetic field by holding a compass at places around a wire carrying an electric current and noting down how much the needle deflects, and in what direction.

The numbers and directions are the magnetic field.

This might seem rather abstract and not much of a simplification, but Maxwell found that by introducing the electric and magnetic fields and placing them centre stage, he was able to write down a single set of equations that described all the known electrical and magnetic phenomena. These picture strips illustrate maps of the Milky Way Galaxy as they appear in different wavelength regions. The fact that the velocity of light can be measured experimentally on a bench top with wires and magnets was the key piece of evidence that light is an electromagnetic wave.

At this point you may be wondering what all this has to do with the story of light. Well, here is something profound that provides a glimpse into the true power and beauty of modern physics. In writing down his laws of electricity and magnetism using fields, Maxwell noticed that by using a bit of simple mathematics, he could rearrange his equations into a more compact and magically revealing form.

His new equations took the form of what are known as wave equations. In other words, they had exactly the same form as the equations that describe how soundwaves move through air or how water waves move through the ocean. But waves of what? The waves Maxwell discovered were waves in the electric and magnetic fields themselves.

His equations showed that as an electric field changes, it creates a changing magnetic field. But in turn as the magnetic field changes, it creates a changing electric field, which creates a changing magnetic field, and so on.

And this will continue to happen forever, as long as you do nothing to them. This is profound in itself, but there is an extra, more profound conclusion. When Maxwell did the sums, he must have fallen off his chair. He found that his equations predicted that the waves in the electric and magnetic fields travelled at the speed of light!

In other words, Maxwell had discovered that light is nothing more than oscillating electric and magnetic fields, sloshing back and forth and propelling each other through space as they do so. In modern language, we would say that light is an electromagnetic wave.

In order to have his epiphany, Maxwell needed to know exactly what the speed of light was. Remarkably, the fact that light travels very fast, but not infinitely so, had already been known for almost two hundred years. However, as the Greek philosophers gave more thought to the nature of light, a debate about its speed of travel ensued that continued for thousands of years.

In one corner sat eminent names such as Euclid, Kepler and Descartes, who all sided with Aristotle in believing that light travelled infinitely fast. In the other, Empedocles and Galileo, separated by almost two millennia, felt that light must travel at a finite, if extremely high, velocity.

He considered light travelling across the vast distance from the Sun to Earth, and noted that everything that travels must move from one point to another.

In other words, the light must be somewhere in the space between the Sun and the Earth after it leaves the Sun and before it reaches the Earth.

This means it must travel with a finite velocity. Aristotle dismissed this argument by invoking his idea that light is simply a presence, not something that moves between things. Without experimental evidence, it is impossible to decide between these positions simply by thinking about it!

Galileo set out to measure the speed of light using two lamps. He held one and sent an assistant a large distance away with another. When they were in position, Galileo opened a shutter on his lamp, letting the light out.

His conclusion was that light must travel extremely rapidly, because he was unable to determine its speed. He was able to do this because if it had been slower, he should have been able to measure a time delay. The question, how fast is the speed of light, has plagued scientists for thousands of years. Part of the answer came from observing how light travels between points: from the Sun to Earth.

The first experimental determination that the speed of light was not infinite was made by the seventeenth-century Danish astronomer, Ole Romer. In , Romer was attempting to solve one of the great scientific and engineering challenges of the age; telling the time at sea. Finding an accurate clock was essential to enable sailors to navigate safely across the oceans, but mechanical clocks based on pendulums or springs were not good at being bounced around on the ocean waves and soon drifted out of sync.

In order to pinpoint your position on Earth you need the latitude and longitude. Latitude is easy; in the Northern Hemisphere, the angle of the North Star Polaris above the horizon is your latitude. In the Southern Hemisphere, things are more complicated because there is no star directly over the South Pole, but it is still possible with a little astronomical know-how and trigonometry to determine your latitude with sufficient accuracy for safe navigation.

Astronomers call this arc the Meridian.

The point at which the Sun crosses the Meridian is also the point at which it reaches its highest position in the sky on any given day as it journeys from sunrise in the east to sunset in the west.

We call this time noon, or midday. Earth rotates once on its axis every twenty-four hours — fifteen degrees every hour. If it reads 2pm when the Sun reaches its highest point in the sky where you are, you are thirty degrees to the west of Greenwich.

Easy, except that you need a very accurate clock that keeps time for weeks or months on end These spectacular star trails are produced in the sky as a result of diurnal motion. This is the motion created as Earth spins on its axis at fifteen degrees per hour, rotating once over twenty-four hours.

The technological challenge of building sufficiently accurate clocks was too great, so scientists began to look for high-precision natural clocks, and it seemed sensible to look to the heavens. Galileo, having discovered the moons of Jupiter, was convinced he could use the orbits of these moons as a clock, as they regularly passed in and out of the shadow of the giant planet.

The principle is beautifully simple; Jupiter has four bright moons that can be seen relatively easily from Earth, and the innermost moon, Io, goes around the planet every 1.

Thus by using the Jovian system as a cosmic clock, Galileo devised an accurate system for keeping time. Despite this, it was clear this technique could be used to measure longitude accurately on land, where stable conditions and high-quality telescopes were available.

In the process of further refining his longitude tables, he sent one of his astronomers, Jean Picard, to the Uraniborg Observatory near Copenhagen, where Picard employed the help of a young Danish astronomer, Ole Romer.

Over the course of several months, the prediction for when Io would emerge from behind Jupiter drifted. At some times of the year there was a significant discrepancy of over twenty-two minutes between the predicted and the actual observed timings of the eclipses. This appeared to ruin the use of Io as a clock and end the idea of using it to calculate longitude.

PDF - Solar System

However, Romer came up with an ingenious and correct explanation of what was happening. These sketches published in Istoria e Dimonstrazione in show the changing position of the moons of Jupiter over 12 days. Jupiter is represented by the large circle, with the four moons as dots on either side. The three black spots are the shadows of the moons Ganymede top left , Io left and Callisto. The white spot above centre is Io, while the blue spot upper right is Ganymede.

Callisto is out of the image to the right. NASA Romer noticed that the observed time of the eclipses drifted later relative to the predicted time as the distance between Jupiter and Earth increased as the planets orbited the Sun, then drifted back again when the distance between Jupiter and Earth began to decrease.

His explanation, which is correct, was simple. Imagine that light takes time to travel from Jupiter to Earth; as the distance between the two planets increases, so the light from Jupiter will take longer to travel between them.

Conversely, as the distance between Jupiter and Earth decreases, it takes the light less time to reach you and so you see Io emerge sooner than predicted.

Factor in the time it takes light to travel between Jupiter and Earth and the theory works. Romer did this by trial and error, and was able to correctly account for the shifting times of the observed eclipses. The first published number for the speed of light was that obtained by the Dutch astronomer Christiaan Huygens, who had corresponded with Romer. Since a toise is two metres seven feet , this gives a speed of ,, metres per second, which is not far off the modern value of ,, metres ,, feet per second.

His measurement of the speed of light was the first determination of the value of what scientists call a constant of nature.

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In the s and s the sound barrier took on an almost mythical status as engineers worldwide tried to build aircraft that could exceed the kilometres per hour miles per hour at which sound travels in air at twenty degrees Celsius. But what is the meaning of this speed limit? What is the underlying physics, and how does it affect our engineering attempts to break it?

Sound in a gas such as air is a moving disturbance of the air molecules. Imagine dropping a saucepan lid onto the floor. As it lands, it rapidly compresses the air beneath it, pushing the molecules closer together. This increases the density of the air beneath the lid, which corresponds to an increase in air pressure. In a gas, molecules will fly around to try to equalise the pressure, which is why winds develop between high and low pressure areas in our atmosphere.

With a falling lid, some of the molecules in the high-pressure area beneath it will rush out to the surrounding lower-pressure areas; these increase in pressure, causing molecules to rush into the neighbouring areas, and so on. So the disturbance in the air caused by the falling lid moves outwards as a wave of pressure. Once we reached 12, metres, the pilot put the Hawker Hunter into the roll and we dived down through the clouds, upside down. Almost immediately, we broke through the sound barrier.

The speed of this pressure wave is set by the properties of the air. To a reasonable approximation, the speed of the sound wave depends mainly on the average speed of the air molecules at a particular temperature. This was known long before aircraft were invented, but it did not satisfy those who wanted to propel a human faster than sound. Many attempts were made during World War II to produce a supersonic aircraft, but the sound barrier was not breached until 14 October , when Chuck Yeager became the first human to pilot a supersonic flight.

Flying in the Bell—XS1, Yeager was dropped out of the bomb bay of a modified B29 bomber, through the sound barrier and into the history books. Today, aircraft routinely break the sound barrier, but the routine element hides the fascinating aerodynamic and engineering challenges that had to be overcome so that humans could travel faster than sound. Test pilot Dave Southwood demonstrated these to me in the making of the programme in a beautiful aircraft that was not designed to break the sound barrier in level flight — the Hawker Hunter.

Designed in the s, the Hawker Hunter is a legendary British jet fighter of the post-war era. Designed to fly at Mach 0. We climbed to 12, metres 42, feet , flipped the Hunter into an inverted dive, then plunged full-throttle towards the Bristol Channel. Then something happened which created the template for all complex life. Two single cells merged together. They got inside each other and, instead of dying, formed a kind of hybrid, which survived and proliferated.

And because every animal and plant today shares the same basic building block — the same type of cell structure — we are very confident that this only happened once, somewhere in the oceans of the primordial Earth. Brian explains how an energy source called a proton gradient may have helped life form at hot underwater vents. That remains one of the greatest mysteries about the origins of human existence. We still don't know how life arose, but it may well have happened at hydrothermal vents - underwater hot springs dotted across the ocean floor.

They churned out a potent mix of chemicals and energy, that may have combined to create the first life. Whatever the truth, many scientists believe that with the right conditions, the chances of life arising are surprisingly high.

But if those conditions had not existed on Earth, our planet today would be a watery soup of complex chemicals, but no more.When they emerged from the Lunar shadow, they saw a crescent Earth rising against the blackness of space and chose to broadcast a creation story to the people of their home planet.

Other editions. The Great Rift Valley is not just an extraordinary geological feature…there is more to this place because the echoes of the history of humanity ring louder across these plains than anywhere else on the planet.

Retrieved November 23, , from nasa. Students can draw the entire solar system or just one solar system object. Shiva is therefore also a regenerative or reproductive power, part of the endless cycle of death and rebirth that is central to the Hindu belief system. Conventional thinking holds that both time and space began at time zero, the beginning of the Planck era.