The formation of the solar system began with the creation of the sun after an exploding supernova caused spherical accumulation of dust particles and gas in a huge swirling cloud called nebula. Planets and other components of the solar system formed in the flat plane of the rotating disc of dust.Know More
The accumulation of dust particles some 4.5 billion years ago triggered a chain reaction. The center of the cloud attracted more dust as its gravitational force soared. The cloud increased its speed of rotation until it flattened into a disc rotating around a dense center. Temperatures at the core rose drastically as the cloud gathered enough energy to set off nuclear reactions. Eventually, the sun formed as hydrogen atoms joined to form helium, discharging huge amounts of energy in forceful eruptions.
The solar system formed two main groups of planets: the four rocky terrestrial planets closest to the sun and the four gaseous jovian planets farthest from the sun. The gaseous planets condensed at lower temperatures, hence their distance from the hot core of the solar system. The rocky and denser metallic materials formed the terrestrial planets because of their ability to condense at higher temperatures closer to the sun.Learn more in Astronomy
Seventeenth-century astronomer Galileo Galilei is widely credited with convincing major church leaders and prominent scientists that the sun, not the Earth, was the center of the solar system. Galileo was the first astronomer to study astronomy with a telescope, which helped him validate Nicolaus Copernicus' early 16th-century heliocentric theories.Full Answer >
According to NASA, astronomers have discovered at least 146 moons orbiting planets in Earth's solar system. As of 2014, 27 more moons await official confirmation of their discovery. This total does not include the six moons of the dwarf planets or tiny satellites that orbit asteroids and other celestial objects.Full Answer >
The geocentric, or Ptolemaic, model of the solar system is the astronomical model advanced by ancient people to describe the motions of the planets, Sun and moon. This model held that the Earth was the center of the solar system, and the other heavenly bodies orbited around it. Scientists now know that this model is incorrect and that the Sun is at the center of the solar system.Full Answer >
Using a formula that astrophysicist Greg Laughlin had created, the planets have been given values in terms of currency. The Earth is valued at five quadrillion dollars, as of February 2011, making it the most expensive among 1,235 other planets.Full Answer >