Know the facts

 Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south and is bounded by the continents of Asia and Australia in the west and the Americas in the east. Area: 165.2 million km² Mean depth: 4,280 m Water volume: 710,000,000 km3 (170,000,000 cu mi) Islands: Bora Bora, Tahiti, Te Ika-a-Māui / North Island, Rarotonga, Jarvis Island, more Bridges: Onahama Marine Bridge At 165,250,000 square kilometers (63,800,000 square miles) in the area (as defined with a southern Antarctic border), this largest division of the World Ocean—and, in turn, the hydrosphere—covers about 46% of Earth's water surface and about 32% of its total surface area, larger than all of Earth's land area combined (148,000,000 square kilometers). The centers of both the Water Hemisphere and the Western Hemisphere are in the Pacific Ocean. Ocean circulation (caused by the Coriolis effect) subdivides ...

 Mercury Mercury is the smallest planet in the Solar System and the closest to the Sun. Its orbit around the Sun takes 87.97 Earth days, the shortest of all the Sun's planets. Density: 5.43 g/cm³ Distance from Sun: 57.91 million km Orbital period: 88 days Length of day: 58d 15h 30m Mass: 3.285 × 10^23 kg (0.055 M⊕) Surface area: 74.8 million km² Radius: 2,439.7 km Mercury rotates in a way that is unique in the Solar System. It is tidally locked with the Sun in a 3:2 spin–orbit resonance, meaning that relative to the fixed stars, it rotates on its axis exactly three times for every two revolutions it makes around the Sun. 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 Mercurian years. Mercury's axis has the smallest tilt of any of the Solar System's planets (about 1⁄30 degree). Its orbital eccentricity is the largest...

 Sun The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as visible light, ultraviolet light, and infrared radiation. Surface temperature: 5,778 K Distance to Earth: 149.6 million km Age: 4.603 billion years Mass: 1.989 × 10^30 kg Radius: 696,340 km Gravity: 274 m/s² Moons: 3122 Florence, 130 Elektra, 90482 Orcus The enormous effect of the Sun on Earth has been recognized since prehistoric times. The Sun was thought of by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of solar calendars, one of which is the Gregorian calendar, the predominant calendar in use today. The Sun's core fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. This energy, which can take between 10,000 and 170,000 years to escape the ...

 Nuclear Fusion Nuclear fusion is a reaction in which two or more atomic nuclei are combined to form one or more different atomic nuclei and subatomic particles (neutrons or protons). ... Fusion is the process that powers active or main sequence stars and other high-magnitude stars, where large amounts of energy are released. The Sun is a main-sequence star, and thus generates its energy by nuclear fusion of hydrogen nuclei into helium. In its core, the Sun fuses 500 million metric tons of hydrogen each second. A fusion process that produces nuclei lighter than iron-56 or nickel-62 will generally release energy. These elements have relatively small mass per nucleon and large binding energy per nucleon. Fusion of nuclei lighter than these releases energy (an exothermic process), while fusion of heavier nuclei results in energy retained by the product nucleons, and the resulting reaction is endothermic. The opposite is true for the reverse process, nuclear fission. This means that th...

 Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, being larger than only Mercury. In English, Mars carries the name of the Roman god of war and is often referred to as the "Red Planet". Gravity: 3.721 m/s² Distance from Sun: 227.9 million km Orbital period: 687 days Surface area: 144.8 million km² Mass: 6.39 × 10^23 kg (0.107 M⊕) Radius: 3,389.5 km Moons: Phobos, Deimos The latter refers to the effect of the iron oxide prevalent on Mars's surface, which gives it a reddish appearance (as shown), that is distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, with surface features reminiscent of the impact craters of the Moon and the valleys, deserts and polar ice caps of Earth. The days and seasons are comparable to those of Earth, because the rotational period as well as the tilt of the rotational axis relative to the ecliptic plane are similar. Mars is the site...

Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandth the mass of the Sun.  Moons: Europa, Ganymede, Io, Callisto, Amalthea, Himalia, Valetudo, Carme, Adrastea, Thebe Surface area: 61.42 billion km² Mass: 1.898 × 10^27 kg (317.8 M⊕) Radius: 69,911 km Orbital period: 12 years Gravity: 24.79 m/s² Distance from Sun: 778.5 million km Jupiter is primarily composed of hydrogen, but helium constitutes one quarter of its mass and one tenth of its volume. It likely has a rocky core of heavier elements, but like the other giant planets, Jupiter lacks a well-defined solid surface. The on-going contraction of its interior generates heat greater than the amount received from the Sun. Because of its rapid rotation, the planet's shape is that of an oblate spheroid; it has a slight but noticeable bulge around ...

 Moon The Moon is Earth's only natural satellite. At about one-quarter the diameter of Earth, it is the largest natural satellite in the Solar System relative to the size of its planet, the fifth largest satellite in the Solar System overall, and is larger than any known dwarf planet.  Distance to Earth: 384,400 km Gravity: 1.62 m/s² Radius: 1,737.4 km Orbital period: 27 days Surface area: 3.793×107 km2; (0.074 of Earth's) Surface pressure: 10−7 Pa (1 picobar) (day); 10−10 Pa (1 femtobar); (night); Satellite of: Earth The Moon's orbit around Earth has a sidereal period of 27.3 days. During each synodic period of 29.5 days, the amount of visible surface illuminated by the Sun varies from none up to 100%, resulting in lunar phases that form the basis for the months of a lunar calendar. The Moon is tidally locked to Earth, which means that the length of a full rotation of the Moon on its own axis causes its same side (the near side) to always face Earth, and the somewhat longe...

 Pluto Pluto (minor planet designation: 134340 Pluto) is a dwarf planet in the Kuiper belt, a ring of bodies beyond the orbit of Neptune. It was the first and the largest Kuiper belt object to be discovered. After Pluto was discovered in 1930, it was declared to be the ninth planet from the Sun. Beginning in the 1990s, its status as a planet was questioned following the discovery of several objects of similar size in the Kuiper belt and the scattered disc, including the dwarf planet Eris. This led the International Astronomical Union (IAU) in 2006 to formally define the term "planet"—excluding Pluto and reclassifying it as a dwarf planet. Pluto is the ninth-largest and tenth-most-massive known object directly orbiting the Sun. It is the largest known trans-Neptunian object by volume but is less massive than Eris. Like other Kuiper belt objects, Pluto is primarily made of ice and rock and is relatively small—one-sixth the mass of the Moon and one-third its volume. It has a mod...

  Steam engine A  steam engine  is a  heat engine  that performs  mechanical work  using  steam  as its  working fluid . The steam engine uses the force produced by steam pressure to push a  piston  back and forth inside a cylinder. This pushing force can be transformed, by a  connecting rod  and  flywheel , into  rotational  force for  work . The term "steam engine" is generally applied only to  reciprocating engines  as just described, not to the  steam turbine . Steam engines are  external combustion engines ,  where the working fluid is separated from the combustion products. The ideal  thermodynamic  cycle used to analyze this process is called the  Rankine cycle . In general usage, the term  steam engine  can refer to either complete steam plants (including  boilers  etc.), such as railway  steam locomotives  and  port...

  Leonardo da Vinci Leonardo da Vinci (15 April 1452 – 2 May 1519) was an Italian polymath of the High Renaissance who was active as a painter, draughtsman, engineer, scientist, theorist, sculptor and architect. While his fame initially rested on his achievements as a painter, he also became known for his notebooks, in which he made drawings and notes on a variety of subjects, including anatomy, astronomy, botany, cartography, painting, and paleontology. Leonardo's genius epitomized the Renaissance humanist ideal, and his collective works compose a contribution to later generations of artists matched only by that of his younger contemporary, Michelangelo. Born out of wedlock to a successful notary and a lower-class woman in, or near, Vinci, he was educated in Florence by the renowned Italian painter and sculptor Andrea del Verrocchio. He began his career in the city, but then spent much time in the service of Ludovico Sforza in Milan. Later, he worked in Florence and Milan again, a...

  Jagadish Chandra Bose Sir Jagadish Chandra Bose CSI CIE FRS ( 30 November 1858 – 23 November 1937 ) was a biologist, physicist, botanist and an early writer of science fiction. He pioneered the investigation of radio and microwave optics, made significant contributions to plant science, and laid the foundations of experimental science in the Indian subcontinent. IEEE named him one of the fathers of radio science. Bose is considered the father of Bengali science fiction, and also invented the crescograph, a device for measuring the growth of plants. A crater on the moon has been named in his honour. He founded Bose Institute, a premier research institute of India and also one of its oldest. Established in 1917, the institute was the first interdisciplinary research centre in Asia. He served as the Director of Bose Institute from its inception until his death. Born in Munshiganj, Bengal Presidency, during British governance of India (now in Bangladesh), Bose graduated from St. Xavi...

  C. V. Raman C.V.Raman or  Sir Chandrasekhara Venkata Raman   FRS  (   7 November 1888 – 21 November 1970) was an Indian physicist known for his work in the field of  light scattering .   With his student  K. S. Krishnan , he discovered that when light traverses a transparent material, some of the deflected light changes its  wavelength  and  frequency . This phenomenon, a hitherto unknown type of scattering of light, was subsequently termed the Raman effect or  Raman scattering .  Raman received the 1930  Nobel Prize in Physics  for the discovery and was the first Asian to receive a Nobel Prize in any branch of science. Born to Tamil Brahmin parents, Raman was a precocious child, completing his secondary and higher secondary education from St Aloysius' Anglo-Indian High School at the ages of 11 and 13, respectively. He topped the bachelor's degree examination of the University of Madras with honours in phy...

  Rigveda The  Rigveda  or  Rig Veda  ( Sanskrit :  ऋग्वेद ) is an  ancient Indian  collection of  Vedic Sanskrit   hymns . It is one of the four sacred  canonical  texts ( śruti ) of  Hinduism  known as the  Vedas . The Rigveda is the oldest known Vedic Sanskrit text. Its early layers are one of the oldest extant texts in any Indo-European language. The sounds and texts of the Rigveda have been orally transmitted since the 2nd millennium BCE. The philological and linguistic evidence indicates that the bulk of the Rigveda Samhita was composed in the northwestern region of the Indian subcontinent, most likely between c. 1500 and 1000 BCE, although a wider approximation of c. 1900–1200 BCE has also been given. The text is layered consisting of the Samhita, Brahmanas, Aranyakas and Upanishads. The Rigveda Samhita is the core text, and is a collection of 10 books (maṇḍalas) with 1,028 hymns (sūktas) in about 10,600 v...

  Vedas Vedas  are a large body of  religious texts  originating in  ancient India . Composed in  Vedic Sanskrit , the texts constitute the oldest layer of  Sanskrit literature  and the oldest  scriptures  of  Hinduism . There are four Vedas: the Rigveda, the Yajurveda, the Samaveda and the Atharvaveda. Each Veda has four subdivisions – the Samhitas (mantras and benedictions), the Aranyakas (text on rituals, ceremonies, sacrifices and symbolic-sacrifices), the Brahmanas (commentaries on rituals, ceremonies and sacrifices), and the Upanishads (texts discussing meditation, philosophy and spiritual knowledge). Some scholars add a fifth category – the Upasanas (worship). The texts of the Upanishads discuss ideas akin to the heterodox sramana-traditions. Vedas are śruti ("what is heard"), distinguishing them from other religious texts, which are called smṛti ("what is remembered"). Hindus consider the Vedas to be apauruṣeya, which means ...

  Rishikesh In September 2015, the Union tourism minister Mahesh Sharma announced that Rishikesh and Haridwar will be the first in India to be given the title of "twin national heritage cities". Due to the religious significance of the place, non-vegetarian food and alcohol are strictly prohibited in Rishikesh. The city has hosted the annual International Yoga Festival on the first week of March since 1989. Rishikesh, also spelt as Hrishikesh, is a city governed by Rishikesh Municipal Corporation (since October 2017), and a tehsil in Dehradun district of the Indian state Uttarakhand. Located in the foothills of the Himalayas in northern India, it is known as the "Gateway to the Garhwal Himalayas" and "Yoga Capital of the World". It lies 21 km (13 mi) north of the city Haridwar and 45 km (28 mi) southeast of the state capital Dehradun. Rishikesh has an approximate population of between 252,533 and 320,222, making it the seventh most populated city in the st...

  Chanakya Chanakya was an ancient Indian teacher, philosopher, economist, jurist and royal advisor. He is traditionally identified as Kauṭilya or Vishnugupta, who authored the ancient Indian political treatise, the Arthashastra, a text dated to roughly between the 4th century BCE and the 3rd century CE. As such, he is considered the pioneer of the field of political science and economics in India, and his work is thought of as an important precursor to classical economics. His works were lost near the end of the Gupta Empire in the 6th century CE and not rediscovered until the early 20th century. Chanakya assisted the first Mauryan emperor Chandragupta in his rise to power. He is widely credited for having played an important role in the establishment of the Maurya Empire. Chanakya served as the chief advisor to both emperors Chandragupta and his son Bindusara. Literary works Two books are attributed to Chanakya: Arthashastra, and Chanakya Niti, also known as Chanakya Neeti-shastr...

  Lodi Gardens Lodi Gardens  or  Lodhi Gardens  is a city park situated in  New Delhi ,  India . Spread over 90 acres (360,000 m 2 ),  it contains,  Mohammed Shah 's Tomb,  Tomb of Sikandar Lodi ,  Shisha Gumbad  and  Bara Gumbad ,   architectural  works of the 15th century by  Lodis  - who ruled parts of  northern India  and  Punjab  and  Khyber Pakhtunkhwa  province of modern-day  Pakistan , from 1451 to 1526. The site is now protected by the  Archaeological Survey of India  (ASI). The gardens are situated between Khan Market and Safdarjung's Tomb on Lodhi Road and is a popular spot for morning walks for the Delhites. Architecture In the middle of the gardens is the Bara Gumbad ("Big Dome"), it consists of a large rubble-construct dome and is not a tomb[citation needed] but was constructed as a gateway to either the attached three domed masjid (mosque) or a...