and by 1532 had basically completed his manuscript entitled ‘De revolutionibus orbium coelestium’ (On the Revolutions of Heavenly Spheres). In his seminal work, Copernicus formulated a fully predictive model of the universe in which the Earth is just another planet orbiting the ...
The Bohr model shows the atom as a small, positively charged nucleus surrounded by orbiting electrons. Bohr was the first to discover thatelectrons travel in separate orbits around the nucleusand that the number of electrons in the outer orbit determines the properties of an element. Who discovere...
Visiting Earth again in 1979, the dematerialisation circuit was fried While the TARDIS was orbiting Earth. The TARDIS was taken on board a Slarvian transport, and the Doctor and Susan learned that the snail-like species planned to conquer Earth by hatching their eggs all over the planet. Thei...
This idea is natural and intuitive. Anyone who stands outside and looks up can clearly see that the stars and the planets are turning around the Earth. But ancients astronomers who studied the heavens found a few problems. Instead of following a straight path in the sky, some of the planet...
yet it was just as surprising to astronomers as their discoveries about distant quasars and colliding galaxies. Peering just 8 billion miles from Earth—the distance light travels in just twelve hours—astronomers were stunned to discover a small planet orbiting the sun. Named Sedna, this most re...
Russian cosmonaut Valentina Tereshkova once said: “If women can be railroad workers in Russia, why can't they fly in space?” On June 16, 1963, Tereshkova did just that. She piloted the Soviet space capsule Vostok 6, spending three days in space and orbiting Earth 48 times. While she ...
Ganymede, Greek Ganymēdēs, Latin Ganymedes, or Catamitus, in Greek legend, the son of Tros (or Laomedon), king of Troy. Because of his unusual beauty, he was
Most planet hunters aren't looking for exoplanets, per se. Those worlds are too small and dim to easily see. They're looking instead for telltale shifts in the light of a star, “wobbles” in its spectral identity caused by the gravitational pull of an unseen orbiting exoplanet. When tha...
It was, in the minds of many astronomers,a bizarre definition. For one, it excluded Earth during its messy early eons. It also left out thousands of confirmed “exo-planets” orbiting stars besides our own. (Catherine Cesarsky, who became the IAU’s president just days after the...
Only good internal quality and beauty will impress people forever and never fade.__【4】__ On the contrary,when people who are fascinated by a person's clothes eventually find out that he is an undesirable person,they would think he is pretentious and may even treat him with contempt(蔑视...