Knowledge Encyclopaedia (BY:Sarvesh Khannukar)

Why are some planets so big?             The largest planets of solar system are the  planets Jupiter and Saturn. Both planets have distinct bands around them with stripes. Saturn  can be recognized easily by its rings. Uranus , uniquely tilted sideways, and the blue Neptune , the coldest of the outer planes, are also much Larger then the inner planets. The outer planets are so big because they are comprised mainly of gases such as helium and hydrogen. These planets have a solid core, which is surrounded by liquid or frozen gas. This reason why they are also known as "gas giants" . Guys if you like this blog comment down below Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/why-does-moon-change-its-shape.html

Why does the moon  change its shape? The moon, which causes high and low tides on the Earth, is a sphere. It does not change it's shape; only our view of it changes. The reason is that unlike the stars, the moon does not produce light, but only reflects the light of sun, since the moon moon goes around the earth once in a mouth, the orientation of the moon, the sun, and the earth respective to one another changes. For this reason, the illuminated part of the moon cannot always be seen clearly from the Earth. Sometimes we see it full, sometimes half, and sometimes not at all. The side of the moon that faces us remains the same. We can see craters and dark spots on the moon, which are known as 'mares'  Guys if you like this blog comment down below. Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/how-far-away-are-stars-from-us.html

How far away are the stars from us? Most of the stars are billions of  kilometres away form us. Billion is the number is nine zeros. However, astronomers specify distances in space in a different unit called, light years, as doing calculations with too many zeros is a problem. A light year is the distance covered by light in one year. The speed of light is 300,000 km/s. If we count the number of seconds in a year(60*60*24*365), and multiply it with the speed of light, we get the distance covered by light in one year: 9460 billion km. Proxima Centauri, the star nearest to the sun, is 4.2 light years away from the Earth. Guys if you like this blog comment down below: Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/are-all-slow-moving-points-are-light.html

Are all slow moving points are light stars?  Most of us think that all points of lights in the sky are stars. But this is not always true. Some of the bright points of light may be planets, which are irradiated by the sun. Some may be remote galaxies, collections of many stars. Unlike the moon and the planets, stars shine by producing their own light. Some stars shine strongly and some weakly. The energy for shining is generated inside the core of the stars. Our sun is also a star and is relatively small in comparison to other stars. Guys if you lik this blog comment down below: Check out my previus blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/what-do-see-in-sky-at-night.html

What do see in the sky at night? If we look at sky  on clear night, we can see the distant stars and constellations and usually the moon. Sometimes we can also see comets or shooting stars, and on seeing them quickly make a wish. It believed that a wish made this way is always fulfilled. With the help of a telescope, we can see many more stars than we do with the naked eyes. Astronomers observe the sky with telescope and keep discovering new stars and galaxy. Guys if you like this blog Comment down below Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/what-happened-550-millions-years-ago.html

What happened 550 millions years ago?                                                    About 550 millions ago, a lot of changes took places on the Earth. At that time probably the whole of the Earth warmed up. As a result, a lot of ice melted and the sea level rose. It is assumed that the composition of sea water became calciferous, turning mollusks that lived earlier in the sea into animals with hard protective calcium shells or calcium skeletons. From that animals started turning into fossils after deaths. The first such animals were the trilobites, and these water later followed by the mussels and ammonites, which are related to the octopus. Guys if you like this blog please comment down below  Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/how-earthquakes-occurs.html

Where do earthquakes occurs?                                                                                                                                                                  Earthquakes occurs mainly at the borders of the plates where two plates slide past each other. Most earthquake occurs in the Himalayan region. The actual seismic center, the 'hypocentre', lies deep below the surface of the Earth. The point on the surface of the Earth lying immediately above this is called 'epicenter'. Scientists can determine this point. They measure the time it takes th...

Why does the Earth tremble sometimes? The moving tectonic plates, in which the uppermost layer of the Earth is divided, not only collide at many places but also often slide past each other. This causes friction and leads to problem once in a while. Stress builds up, which then gets discharged very quickly. there is a jerk-the Earth trembles. This gives rise to shock waves that can cause a lot of damage at places, depending on the intensity of the earthquake and where they occur. Luckily, to some extent we can protect ourselves from these waves. A tsunami occurs if the center of the earthquake lies below the sea. Guys If you like this blog please comment down below. Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/where-are-volcanoes-found.html

Where are volcanoes found? Volcanoes are found primarily at the borders of the plates, where the oceanic Earth's crust submerges below another plate, melts in the depth, and magma rises. This is generally the cases all around the Pacific Ocean. Here, the Cocos and the Nazca plates submerge below the middle and South America  and the Pacific plate submerges below the small plates in Southeast Asia. Volcanoes are found in areas ranging from Italy To Turkey and Iran up to the Indonesian islands. Very rarely will we find volcanoes in the middle of a plate. These occur only in 'hot spots' which are areas with high volcanoes activity, such as the Hawaiin Islands. Please comment down below if you like this blog and you can check my previous blog link is given below .. Check my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/why-do-people-leave-near-volcanoes.html

Why do people leave near volcanoes?                                                                           Farmers prefer to settle near volcanoes because the soil is very fertile due to the lava and volcanic ash deposits. When the volcanoes erupts, people leave the place for some time, and return to the risk zone after the eruption because the safer places are already inhabited. Moreover, for many people the area around the volcanoes is home, which they do not want to leave. If you like this blog please comment down below ... Check Out My previous blog here https://ourearthintheuniverse1.blogspot.com/2020/05/when-do-volcanoes-become-dangerous.html

When do volcanoes become dangerous? We can call a volcano dangerous only when it causes damage to human life. For instance, if a volcano erupts on the almost uninhabited East-Asian peninsula of Kamchatka, it is hardly reported in the news. But, if a volcano starts spewing hot gases and ash in a densely populated area, many lives are at risk. Explosive volcanic eruptions discharge huge quantities of dust and ash, often burying neighboring areas. Thin, dark magma can flow at a fast speed of up to 100 km/h marking it eruptions can also have far-reaching consequences. When the Indonesian volcanic Krakatoa erupted in 1883, the volcanic ash reached up to a height of 80 km, which for some time darkened the sky worldwide.  Guys if you like this blog please comment down below Read my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/why-do-we-have-different-types-of.html

Why do we have different types of volcanoes?                             Since the material coming out of the Earth's core is different in different areas, the resultant changes are also different. if the magma is very hot, more than 1000᷾ C, it is dark, thin and mostly flows quietly. The sides of such volcanoes have gradual slopes. Colder, and hence more viscous, magma often erupts in explosions. The volcanic cone is steeper. Because of the heat in the Earth's core,geysers (water fountains), solfataras (discharge of hot sulfuric gases), and hot water sources are found near the volcano. These are often used for heating in places such as Iceland. Guys if you like this blog comment down below  And if you More blogs on this comment down below. Read My Previous Blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/how-are-volcanoes-formed.html

How are volcanoes formed? Volcanoes are natural phenomenon that occurs everywhere, but some places are more then others. The molten rocks and gases in the mantle called magma pushes its way upwards and pours to surface through cracks in the crust. This is a volcano. There are different types of volcanoes; some are explosive others are not, and all erupt as spectacularly as we see on the television. Some eruptions take place unexpectedly, but others can be predicted, which is very important for the people near a volcano. So Guys if you like this blog comment me down below and tell me which blog you want next on my site.                                                                 Check out my previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/how-are-new-sea...

How are new seas formed?     Seas arise at place where the Earth's crust cracks open due ti expansion.Around 200 million years ago the Atlantic was formed in this way. Today in Earth Africa,a crack from Malawi to Ethiopia has formed as a result of the eruption of a volcano. If the soil sinks further, water from the oceans will enter  the region to give rise to a water body. this has already happened in the case of Red sea, the continuation of the east African rift system. If the plate continues to expand,then at some point of time it breaks completely giving rise to a long mid-ocean volcanic ridge.                                                                                                      ...

How were mountains formed? Mountains are formed in two ways. When the tectonic plates (Solid Rocks)  moves , they collide against each other. When the heavy oceanic part of the plate collides with the continental part, it submerges below it. The Andes , for instance, were formed in this way.   The other way is when two continents collide with each other, the plates bend at the point of Contact and fold up steeply. The Himalayas or the Alps were formed in this way around 35 millions years ago and are counted among the 'young' mountains of the world. Old mountains, such as Black Forest or the Harz mountains, are lower range because peaks have been worn down by rain, ice, and wind over time.                                       If You like this blog please comment down below or if you are having any doubts comment below or Contact me.        ...

Who discovered the continental drift?                                                   This discovery is credited to the German geologist Alfred Wegener. He not only discovered that the coastline of South America fits Very well against that of Africa but also showed that the fossils in both the coastal regions are similar. He also proposed another idea: about 300 million years ago there must have been a single, continuous landmass that somehow broke up and gave rise to several parts-the tectonic plates. The continents on these plates drifted away from one another and then rejoined the way they are today. Thus, landmass were displaced, and their position is changing even today. The tectonic plates are still moving at a speed around 6 cm per year.    If you like this blog please comment down below or if you have any question c...

How many plates does the Earth's crust have? The relatively solid earth's crust and a part of the layer that lies below it-is divided into seven large and more than smaller plates. These plates float over the hot , viscous layer, which is constantly in motion-like boiling soup. These flushes of heat in the Earth's interior are known as 'convection cells' at places where the convection currents push the rocks upwards , the crust often breaks and gives rise to a new crust. For example, the mid-ocean ridges in the Atlantic and Pacific oceans.           If you like this blog please comment down below                                                                                                       ...

Did the Earth always look as it does today? No, since its origin about 4.8 billion years ago, our planet has undergone a lot of changes. the initial ball of fire cooled down and the surface slowly turned solid. Today we know that the Earth's crust is dived into several plates, which moves continuously. Entire continents have been displaced and mountains, islands, and new seas have been formed or have disappeared. Even the flora and fauna have evolved over time. Many species have become extinct and new ones have been discovered. This development of the earth over billions of years is known as the history of the Earth.   If you like this blog please comment down  below                                                                                ...

What is the atmosphere made up of? The word 'Atmosphere' means a gaseous cover enveloping a planet. without atmosphere life would not have been possible on the Earth: One-fifth of the atmosphere is oxygen and fourth-fifth is nitrogen. Like the earth's interior, the atmosphere too is made up of several layers.All animals and plants live in the lowermost layers of the atmosphere called the 'troposphere'. All weather phenomena take place in the troposphere. Even aeroplanes fly in the outer edge of the troposphere. The stratosphere, the mesosphere,the ionosphere, and the exosphere lie above the troposphere.                                                                                                         ...

Why do we not fall off from the Earth?   Gravity is the force of the Earth that attracts every object towards itself. From our perspective this force always acts downwards. For a long time people did not believe that the Earth is round because then the people 'underneath' the sphere would have actually fallen down. In 1687, a physicist, Isaac Newton, proved that the force  of gravity always acts toward the center  of the Earth. On the Earth, the force of gravitation always acts 'downwards' irrespective of Eskimos in the Arctic region, people in the Europe or inhabitants of Australia.           If you like this blog please comment down  below                                                                             ...

How did we discover that the Earth is round?                                       About 3000 years ago people believed  that the Earth is Flat. But people wondered why ships disappeared at the horizon. Sailors too returned from journeys and were proof that ships did not fall off the edge of the Earth. The simplest explanation was: the Earth must be round. The final proof came in the year 1522 after the expedition of Ferdinand Magellan, who was the first to sail around  the Earth.         If you like this blog please comment down  below   Read the previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/how-do-we-discover-what-is-inside-earth.html

How do we discover what is inside the Earth?                     Caves and mines go only up to 1-2 km inside the Earth. Even the deepest wells of the world, Such as the one 12 km deep in the Russian Kola Peninsula or the 9 km deep one in the Upper Palatinate,hardly scratch the Earth's crust. One can 'look' deep inside the Earth in the aftermath of earthquakes or by creating nuclear explosions. The explosions generate sound or seismic waves. they also throw off rock particles. By measuring  their intensity and timing, scientists  discover the composition of the Earth's interiors.                If you like this blog please comment down  below                                                          Read previous ...

What is the internal structure of the Earth? Like an onion, the Earth has several layers. The outermost layer, the Earth's crust,has an average depth of about 40 km. as compared with diameter of the earth, which is around 12,700 km, the earth's crust is very small. it is primarily made up of solid rocks. below the crust is the mantle, reaching to a depth of about 2900 km. due to the heat inside the earth, the mantle consists of solid and molten rocks. below the mantle is the core, made up of iron and nickle. the deeper one travels inside the earth, the hotter it is. The temperature in the core is between 4000 and 5000'c.    If you like this blog please comment down  below   Read the previous blog here: https://ourearthintheuniverse1.blogspot.com/2020/05/what-is-external-structure-of-our-earth.html

What is the External Structure of the Earth? It has been known for more than 2000 years that the earth is round, but we were able to actually see this much later only when we flew into space. The Journey as describe by author Jules in his book journey to the center of the Earth was, after all, impossible. Only one thing that was known: the earth is made up of  " Soil, Rocks, and Water". Today, we know that the earth is also surrounded by an air cover called the atmosphere.   If you like this blog please comment down  below