The Universe: Cosmos and Geocentric Concepts

Chapter 1: The Universe

• The human mind created the term "COSMOS" when it conceptualized the entire universe in an organized manner.
• Claudius Ptolemy, a renowned astronomer of the Egyptian-Greek tradition, initiated systematic study of the cosmos and introduced the geocentric concept, which suggested The Earth is at the center of the universe.
• According to the geocentric concept, the Earth is at the center of the cosmos, with the sun and other planets orbiting it. This idea remained popular for a long time.
• Nicolaus Copernicus proposed the heliocentric concept in 1543, which posited a revolutionary shift in understanding the universe with The Sun, rather than the Earth, being at the center.
• Although Copernicus's theory concerning the cosmos was confined to the solar system, it altered the course of cosmic research.
• British astronomer William Herschel discovered in 1805, with the use of a telescope, the solar system is only a small component of the galaxy.
• Edwin P. Hubble, an American astronomer, demonstrated in 1925 that the visible universe has a diameter of 250 million light-years, containing millions of galaxies like our own Milky Way.
• The understanding of the cosmos has evolved, and several theories have been proposed to explain the universe's emergence.

Theories Related to the Origin of the Universe

• Big Bang Theory: Proposed by George Lemaître.
• Steady-State Theory: Proposed by Thomas Gold and Hermann Bondi.
• Pulsating Universe Theory: Proposed by Dr. Alan Sandage.

Big Bang Theory

• The Big Bang Theory is considered the most accepted model for the universe's origin and was proposed by George Lemaître; in the 1960-70s.
• According to the Big Bang Theory, the universe originated from an explosion around 15 billion years ago.
• The dispersion of matter happened as a result of the events that caused this explosion - Cosmic Explosion, or Big Bang- forming black and ordinary matter.
• Aggregation of matter led to the formation of several cosmic entities and common matter accumulated, causing their size to grow, resulting in the formation of galaxies.
• Explosion materials regrouped to create stars and, planets and satellites formed later in the same way.
• With evidence gathered from the widening distances between galaxies, the "Big Bang" has caused the cosmos to develop, and its steady expansion continues.
• The European Center for Nuclear Research (CERN) did the Large Hadron Collider (LHC) experiment on March 30, 2010 to decipher the secrets of the cosmos by building a 27 km tunnel 100 feet beneath the Earth's surface in Geneva.
• More than a thousand scientists took part in the Proton beams that were made to collide at roughly the speed of light to create 'Higgs Boson' by this historical experiment.
• This experiment will probe the unresolved mysteries of the cosmos, such as dark matter, dark energy, extra dimensions, and the God Particle.
• Scientists want to recreate in the lab the cosmic event that took place 15 billion years ago. This event is called the "Big Bang."
• The 'Higgs Boson', called the 'God Particle', reveals the mysteries of the cosmos because it is considered the most basic unit.
• CERN ultimately revealed the discovery of the sub-atomic particle Hix Boson on July 4, 2012.
• It is regarded as a landmark discovery in understanding the mysteries of the cosmos. The Large Hadron Collider was closed on February 14, 2013, and reopened in June 2015.
• There are about 100 billion galaxies in the universe; Galaxies are clusters of innumerable stars with a central bulge.
• The bulge refers to the center of galaxies, where there is a huge population of stars; Each galaxy has about 100 billion stars.
• Lyman Alpha Blobs are a cluster of galaxies and gases that are amoeba-shaped, 200 million light-years.
• Galaxies in this structure are four times closer to each other than the other Galaxies in the cosmos; The Andromeda Galaxy is the galaxy closest to our Milky Way, 2.2 million light-years from our galaxy.
• Our Milky Way galaxy is called the Mandakini.
• Nebulae, like the Orion Nebula, are the galaxy's coolest and brightest stars. The galaxy is one lakh light years wide.
• The sun, which orbits the galaxy in over 200 million years, is a star in our galaxy; planets like the Planemos are a pair of objects that look very similar outside of the solar system.
• Sirius or Dog Star, which has Earth about nine light years distant and has two times the mass of the Sun, is about 20 times brighter than the sun.
• The closest star to the sun is Proxima Centauri and 4.3 light-years away.
• Looking into the sky at night for the first time in 1609 using a telescope, Galileo found stars that are invisible to the naked eye.
• The Indian Space Research Organization launched the Solar Telescope MAST in Udaipur, Rajasthan on August 4, 2015.
• This telescope could capture a digital velocity image of the sun per minute, providing more information about it and celestial activity during the day.
• China is building the world's largest radio telescope, FAST, which will surpass NASA's Kepler telescope when built.

Stars: Birth and Death (Lifecycle)

• Cloud of gas and dust existing in the universe, rotation in the galaxy affects it and that causes it core nuclear fusion begins and the process of hydrogen turning into helium begins. This is when it becomes a star.
• When the hydrogen in the center is gone, the stars core shrinks and heats up, but hydrogen keeps turning into helium on the outside; gradually, the star cools and turns red, called Red Giants.
• After that, helium turns into carbon and carbon into heavier like iron. As a result, the core bursts which is called Supernova.
• If the stars mass is less than Ms (Ms is the suns mass is), it loses its nuclear energy and turns into White Dwarf.
• A white dwarf also known as Fossil Star, turns cold and becomes Black Dwarf.
• Called Chandrasekhar limit, 1.4 Ms, free-ranging electrons get too fast and leave the nucleus and leave Neutrons. This phase is called Neutron Star, or Pulsar.
• Neutron keeps shrinking and in the Neutron, the huge amount of mass in the end only shows at one point. It's also called a Blackhole.
• Because light can't even get away with in the dark, that's why it is unseen, and John Wheeler is the one who gave the Blackhole its concept.
• When a blackhole is a group then it's known as Rog Blackhole; a quasar is a bright space object that releases a huge amount of energy.
• NASA found the oldest star and it's Kepler 444.

Solar System

• The solar system consists of the sun, 8 planets, 172 satellites, comets, meteors, and asteroids.
• The sun, which is the origin of the solar system, is a star that provides energy and light; Source of the sun's energy is hydrogen atoms into helium.
• The part of the sun that we can see with eyes is the photosphere; The outer part of the sun that is only visible during a solar eclipse is the corona.
• Sometimes, the storm of atoms from the photosphere comes out so with so, the force of attraction crosses goes to the space; solar flares;
• While going through Earth's atmosphere touches particles and produces Aurora Light which can be seen at North and South Pole.
• Solar flares appear as dark spots where solar flares originate; these are called sun spots, which are cooler parts, about 1500 degrees.
• Sun spots exert a strong magnetic radiation that disrupts Earth's wireless communications.
• The process of their formation is called the Solar Flair cycle and happens about 11 years.
• To study sun and protect electrical system organization ISRO made Aditya-1 and it's going to launch the first satellite in 2017 during that time.
• It is through solar coronagraphy that solar radiation is obtained.

Specific Facts Related to the Sun

• The minimum distance from the sun to the Earth is 147 million km (14.70 crore)
• The farthest distance from the sun to the Earth is 152.1 million km (15.21 crore)
• The average distance from the sun to the Earth is 149.8 million km (14.98 crore)
• The Sun's diameter is 1,392,000 km.
• The Volume - 13 lakhs times bigger than the Earth
• The Mass - 3,32,000 times bigger than the Earth
• The area surrounding the Sun is 28 times around the Earth.
• Central Density - 100 grams in each cubic cm
• Hydrogen-71% of chemical composition
• Helium 26.5% of chemical composition
• Other element 2.5% of chemical composition
• Photosphere temperature (Surface Temperature) - 6000°C
• Temperature in middle is 15 million °C
• Sun spot temperate is 1500°C
• Energy emission is 1026 joules/second (1026J/s)
• Central pressure is 1 Arab atmosphere unit.
• Rotation speed - 25.38 days (equator related
• 33 days related to the poles
• The Sun's age is 5 billion years
• Common Star life is 10 Billion years
• Takes 8 minutes, 20 seconds to arrive the Earth
• The speed of light is 3 × 108 m/s, 30000 km per sec

Planet

• A radiantless celestial body that revolves around stars is called a planet; these are made from stars and circle the sun.
• These don't have their own light but are illuminated from the sun and absorb the sun's heat.
• All rotate from west to east only but not planet Venus and Aruna: Mercury, Venus, Earth and Mars are those
• The planets move, in an eastern west rotation
• The interior planets are Mercury, Venus, Earth and Mars and composed of heavy materials while external planets are Jupiter Saturn Auna and Varura.
• Solar system has eight planets.

Modified Solar System

• Mercury. As small as the planet, close to the sun and is closest to the Solar system is called 'great planets'. Mercury is the smallest planet.
• It's a small planet and it takes 88 days to complete one orbit. It is planet Earth and Mercury that exist in the interiors between the sun and that are known as endotherms. It's not possible because no wind and very
• There is none available so both days and nights are freezing; which is why life cannot survive on Mercury. The temperature range is the highest in all planets- (560°C), one day on Mercury is equivalent to one month or 90 days.
• Venus: The 2nd planet, as it is closest to the sun. Rotation happens 225 day. it's closest planet to Earth and known as star of morning. The planet is also to smaller similar in surface and so known "Sister of Earth", no oxygen.
• Earth: This world, called "Earth," is third solar planet. This Earth does movement from the West.

Six / Geography

• The earth circles at an altitude of 23 1/2
• Average distance: 150 km from Sun
• Orbit: Approx 365 days from sun
• Only planet where air is available for life

4. Mars

• Fourth planet from the sun and completes circle the earth in 687 days
• Surface is red
• Thin atmosphere
• Rotates like earth and Phobos and Deimos are two orbits (Deimos smallest and Nix, is highest mountain
• From the planet, certain statistics are discovered: Diameter diameter is 6,794 kilometers.
• Its surface is known to be -87°C to- 5°C and a carbon, oxygen, nitrogen air. Several expeditions have confirmed these as welll.
• Many campaigns are activated to preserve surface water.

Seven: One Summary Planet

• Jupiter is the largest planet in the solar system.
• The earth complete circle of the one kilometer is 11.9 years and planets are its 67 satellites with the largest.
• Around the plane of their 295 Earth one in 43 with rotation activity and the largest.
• Earth is to Saturn second largest and a few are visible there
• Saturn revolves once one kilometer diameter and in the air is Hydrogen.
• Several missions there have been in fact and an activity that takes place amongst the people.
• This planet is known to be the closest for scientific process to the Earth as well.
• There are several asteroids in-between for a good

Explore the evolution of understanding the universe, from the concept of 'COSMOS' to Ptolemy's geocentric model. Discover Copernicus's heliocentric concept and Herschel's discovery of the solar system's place in the galaxy. Learn about early astronomy.