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Science

Atomic number

The atomic number or proton number of a chemical element is the number of protons found in the nucleus of an atom. It is identical to the charge number of the nucleus. The atomic number uniquely identifies a chemical element. In an uncharged atom, the atomic number is also equal to the number of electrons.

Science

Moon

The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite. It is the fifth-largest natural satellite in the Solar System, and the largest among planetary satellites relative to the size of the planet that it orbits. The Moon is after Jupiter's satellite Io the second-densest satellite in the Solar System among those whose densities are known.

Art, Science

Bill Nye

William Sanford Nye, popularly known as Bill Nye the Science Guy, is an American science communicator, television presenter, and mechanical engineer. He is best known as the host of the PBS and syndicated children's science show Bill Nye the Science Guy (1993–1998), the Netflix show Bill Nye Saves the World (2017–present), and for his many subsequent appearances in popular media as a science educator.

Science

Valery Legasov

Valery Alekseyevich Legasov was a prominent Soviet inorganic chemist and a member of the Academy of Sciences of the USSR. He is now mainly remembered for his work as the chief of the commission investigating the Chernobyl disaster.

Science

Solar System

The Solar System is the gravitationally bound planetary system of the Sun and the objects that orbit it, either directly or indirectly. Of the objects that orbit the Sun directly, the largest are the eight planets, with the remainder being smaller objects, such as the five dwarf planets and small Solar System bodies. Of the objects that orbit the Sun indirectly—the moons—two are larger than the smallest planet, Mercury.

Science

Earth

Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago. Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.

Technology and industry, Science

Nikola Tesla

Nikola Tesla was a Serbian American inventor, electrical engineer, mechanical engineer, physicist, and futurist who is best known for his contributions to the design of the modern alternating current (AC) electricity supply system.

Science

Cannabidiol

Cannabidiol (CBD) is a naturally occurring cannabinoid constituent of cannabis. It was discovered in 1940 and initially thought not to be pharmaceutically active. It is one of at least 113 cannabinoids identified in hemp plants, accounting for up to 40% of the plant's extract. As of 2018 in the United States, Food and Drug Administration approval of cannabidiol as a prescription drug for medical uses has been limited to two rare forms of childhood epilepsy.

Science

English language

English is a West Germanic language that was first spoken in early medieval England and is now a global lingua franca. Named after the Angles, one of the Germanic tribes that migrated to the area of Britain that would later take their name, England, both names ultimately deriving from the Anglia peninsula in the Baltic Sea. It is closely related to the Frisian languages, but its vocabulary has been significantly influenced by other Germanic languages, particularly Norse, as well as by Latin and French.

Science

Helium

Helium is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements. After hydrogen, helium is the second lightest and second most abundant element in the observable universe, being present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this figure in the Sun and in Jupiter. This is due to the very high nuclear binding energy of helium-4 with respect to the next three elements after helium. This helium-4 binding energy also accounts for why it is a product of both nuclear fusion and radioactive decay. Most helium in the universe is helium-4, the vast majority of which was formed during the Big Bang. Large amounts of new helium are being created by nuclear fusion of hydrogen in stars.

Science

Sun

The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, with internal convective motion that generates a magnetic field via a dynamo process. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometers, i.e. 109 times that of Earth, and its mass is about 330,000 times that of Earth, accounting for about 99.86% of the total mass of the Solar System. About three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.

Politics, Science

A. P. J. Abdul Kalam

Avul Pakir Jainulabdeen Abdul Kalam was an Indian scientist who served as the 11th President of India from 2002 to 2007. He was born and raised in Rameswaram, Tamil Nadu and studied physics and aerospace engineering. He spent the next four decades as a scientist and science administrator, mainly at the Defence Research and Development Organisation (DRDO) and Indian Space Research Organisation (ISRO) and was intimately involved in India's civilian space programme and military missile development efforts. He thus came to be known as the Missile Man of India for his work on the development of ballistic missile and launch vehicle technology. He also played a pivotal organisational, technical, and political role in India's Pokhran-II nuclear tests in 1998, the first since the original nuclear test by India in 1974.

Science

Black hole

A black hole is a region of spacetime exhibiting gravitational acceleration so strong that nothing—no particles or even electromagnetic radiation such as light—can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of the region from which no escape is possible is called the event horizon. Although the event horizon has an enormous effect on the fate and circumstances of an object crossing it, no locally detectable features appear to be observed. In many ways, a black hole acts like an ideal black body, as it reflects no light. Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe.

Art, Science

Gerald Durrell

Gerald Malcolm Durrell, was a British naturalist, zookeeper, conservationist, author, and television presenter. He founded the Durrell Wildlife Conservation Trust and the Jersey Zoo on the Channel Island of Jersey in 1959. His memoirs of his family's years living in Greece were adapted into the television series The Durrells, and he wrote a number of books about his life as an animal collector and enthusiast, the most famous being My Family and Other Animals. He was the youngest brother of novelist Lawrence Durrell.

Science

MDMA

3,4-Methyl​enedioxy​methamphetamine (MDMA), commonly known as ecstasy (E), is a psychoactive drug primarily used as a recreational drug. The desired effects include altered sensations and increased energy, empathy, and pleasure. When taken by mouth, effects begin after 30–45 minutes and last 3–6 hours. As of 2018, MDMA has no approved medical uses.