On 22nd April of every solar year, the high-spirited inhabitants of the planet, Earth, adore the diminutive locality of it, celebrating “International Mother Earth Day”. That seeks to promote, creating a fair balance between the earth and nature and the social, economic, and environmental requisites of current and future generations. Besides, we are enjoined to venerate the ecosystems of Earth, its water reservoirs, its N2 and O2 brim-full atmosphere, and its bountiful and tempting natural beauties. Although, the Earth is the only planet, in eight planets of our solar system, to have such peculiar and distinctive properties, yet, its such undeniable affluence doesn’t restrain us from querying about the outer space. Unless, we brief shortly about Earth, we can’t proceed on to the outer space bodies. The article is to focus, primarily, on to the expatiation of the marvelous extraterrestrial entities. Commencing with the planets of our solar system, particularly, Earth:
PLANETS: The planets are categorized into two definite divisions; one is terrestrial or Earth-like and second is Jovian or Jupiter-like planets. The terrestrial planets are inclusive of Mercury, Venus, Earth, and Mars, while the Jovian planets contain Jupiter, Saturn, Uranus, and Neptune. The distance of 93 million miles between Earth and the sun, termed as one Astronomical Unit (A.U), is weighed up a very helpful cosmic yardstick, in determining the distances of planets to sun. The terrestrial planets whirl steadily, taking between 100 and 250 days to complete one rotation, whereas, the Jovian planets gyrate in less than one day. Terrestrial planets are rock-strewn and small; on the other hand, Jovian planets are prodigious and composed of gaseous components. Bringing into focus our planet: “Earth” is a Germanic word, meaning, “ground”. The contemplating minds propose that, Earth was formed 4.6 billion years ago, the very same time, sun and planets (solar system) were coalesced from Solar Nebula. The third planet from sun and the fifth largest amongst five planets, dubbed ”spheroid”, has a diameter of 7,918 miles (12, 747.98 kilometers). The core of the earth is nearly 4,400 miles (7, 084 kilometers) wide, which encompasses the outermost and innermost core. The outermost 1,400 miles (2,254 kilometers) and innermost 1,600 miles (2,576 miles) of Earth’s core are contained of liquid and solid portions (iron and nickel) respectively, and the two together, act as a dynamo as the Earth rotates, creating the magnetic field extending over thousands of miles, which aids to deflect injurious particles, coming from outer space (outer space initiates 100 miles above the Earth). It is equipped with one natural satellite (moon) only. With the orbital velocity of 18.5 miles/second, it takes 23. 934 hours to take a trip around its axis (culminating in the coming of day and night) and 365. 25 days to complete its orbit about sun.
ASTEROIDS: Asteroids are tiny and rocky bodies that inhabit the interplanetary orbits between Mars and Jupiter. The planetary science denominates these rocky bodies “Minor Planets”, a term operational, to designate solar system bodies, not larger than moons. The largest and smallest asteroids are Ceres (480 miles, discovered in 1801 by Giuseppe Piazzi, named after Roman goddess of harvest) and 1991 BA (6 meters) particularly. The wide gap in space between Mars and Jupiter, if applied with mathematical progression “Titius’-Bode’s law”, predicted that an undiscovered planet resided the gap. Today, it is suggested that at some time, two or more proto-planets collided, forming the Asteroid Belt or it has been formed, reckoning the remnants of the planet, failed to be formed during the development of solar system. Moreover, the colossal build-up and gravitational pull of Jupiter eschewed these bodies to conjoin or corporate into one. It is to be believed that, 65 million years ago, asteroids led to the extinction of dinosaurs, when the asteroid impacts were very prevalent, but afterwards, they faded or lessened out in numbers and intensity, reaching Earth’s surface in the form of meteoroids. The notable asteroids are Pallas, Juno, Icarus and Vesta.
COMETS: Comets are the small spheres, accompanied by the substantial volatile ices and dust, between the stars and the sun. The word “comet” has its origin in Greek language, which means “long-haired”. The comet, Halley’s Comet approaches the sun every 75 years, which is the most famous periodic comet (a comet, have the orbital periods less than 200 years). These’re glittering objects in the sky with their lustrous coma and dust and ion tails. It must be elaborated that, what goes in the comet, that leaves its tail, shining. When a comet leans towards the sun (and it’s active), the outer layer of it vaporizes and builds up a gaseous envelope called a Coma around the solid nucleus, which contains water ice. Particles of iron and rock, entrapped in the nucleus are released in the coma. Thence, solar radiation exerts pressure on the coma and compels the particles away from the direction of the sun, forming a tail. Particles in the tail shine by reflected sunlight. The distinctive sections of comet’s structure are: nucleus, coma, hydrogen cloud, dust tail, and ion tail.
Meteors: At the last of preceding paragraph, particles, formed up become the interplanetary dust. And when the earth revolves, it sweeps up these particles, and which burn up as bright streaks in the atmosphere called meteors. There’re two kinds to meteors: i. sporadic meteors, which can be observed any clear night of the astronomical year, and ii. Periodic meteors, which appear in showers from a particular point, for instance, Orionid meteor shower occurs in October, sourced by Halley’s comet.
BLACK HOLES: The most conversed and worshipped cosmological body, among the celestial objects, is Black Hole. The prediction of such enchanting or bewitching bodies comes forth with the advent of, the most extoled theory in the astronomical world, general theory of relativity (Albert Einstein) in 1916, which declared that when a star expired, it would leave behind a small, concentrated or dense residuum core. Furthermore, the discovery of the first black hole ( Cygnus X-1) dates back to 1971 and coinage, one of the least common processes of words-formation in English language, of the term, ‘black hole’ has association with American astronomer John Wheeler, who invented it in 1967. The black holes are classified into three kinds, in accordance with the differentiation in concentration (covering a smaller region, in correspondence to strong gravitational force, though massive)as: 1. stellar black holes, 2. Intermediate black holes, and 3. Supermassive black holes. Astrophysicists believe that there is nearly 10 million-1 billion stellar black holes in the universe and all are comprised of three layers- the outer and inner event horizon (the boundary around the black hole’s opening) and singularity (the inner region, where the mass of a black hole is concentrated). Under classical physics, it is affirmed that nothing (nay, even light) can escape from a black hole but Quantum mechanics denies such ridiculous interpretations, as it states, that against a particle, its antiparticle is formed also, thus, the mentioned conception is likely to be asseverated by citing, “Hawking Radiations’, which are radiated from a black hole.
Furthermore, the multiverse, besides the acknowledged factual elaboration of the world (comprising of the constellations and galaxies), is constituted by some unknown prodigious structures, awaiting us, to scout. And we’re willing to explore them whilst living our impermanent (predetermined) lives, cruising for the everlasting (till doomsday) bodied structures.