How was our solar system formed?
The Sun and the planets formed together, 4.6 billion years ago, from a cloud of gas and dust called the solar nebula. A shock wave from a nearby supernova explosion probably initiated the collapse of the solar nebula. The Sun formed in the center, and the planets formed in a thin disk orbiting around it.
How did planetesimals form planets?
The Birth of the Planets. Each planet began as microscopic grains of dust in the accretion disk. The atoms and molecules began to stick together, or accrete, into larger particles. By gentle collisions, some grains built up into balls and then into objects a mile in diameter, called planetesimals.
What is the evidence that the solar system was formed about 4.6 billion years ago?
Our solar system began forming about 4.6 billion years ago within a concentration of interstellar dust and hydrogen gas called a molecular cloud. The cloud contracted under its own gravity and our proto-Sun formed in the hot dense center. The remainder of the cloud formed a swirling disk called the solar nebula.
What were the main stages of the solar system formation theory?
Stages of Star System Formation Contraction: The cloud starts collapsing under its own gravity; over 100,000 years, it shrinks down to 100 AU, heats up (thermal energy), and compresses in the center. Accretion disk: The matter around the center spins up and flattens into a disk, while heat vaporizes the dust.
How old is our galaxy?
13.51 billion years
Milky Way/Age
Astronomers believe that our own Milky Way galaxy is approximately 13.6 billion years old. The newest galaxy we know of formed only about 500 million years ago.
What is the name of our solar system?
Our planetary system is named the “solar system” because our Sun is named Sol, after the Latin word for Sun, “solis,” and anything related to the Sun we call “solar.” Our planetary system is located in an outer spiral arm of the Milky Way galaxy.
What are the 2 main types of planets?
Planets are generally divided into two groups: the terrestrial and the giant planets. The terrestrial planets are the four inner planets: Mercury, Venus, Earth, and Mars.
What are two major differences in the composition of the inner and outer planets?
The four inner planets have slower orbits, slower spin, no rings, and they are made of rock and metal. The four outer planets have faster orbits and spins, a composition of gases and liquids, numerous moons, and rings. The outer planets are made of hydrogen and helium, so they are called gas giants.
What is meant by solar nebula?
Solar nebula, gaseous cloud from which, in the so-called nebular hypothesis of the origin of the solar system, the Sun and planets formed by condensation. Swedish philosopher Emanuel Swedenborg in 1734 proposed that the planets formed out of a nebular crust that had surrounded the Sun and then broken apart.
How long did it take to form our solar system?
Over time, these clumps slowly compact into a giant planet. These planets can form faster than their core accretion rivals, sometimes in as little as 1,000 years, allowing them to trap the rapidly vanishing lighter gases.
What are the major influences in the formation of the solar system?
Our solar system formed about 4.5 billion years ago from a dense cloud of interstellar gas and dust. The cloud collapsed, possibly due to the shockwave of a nearby exploding star, called a supernova. When this dust cloud collapsed, it formed a solar nebula—a spinning, swirling disk of material.
What holds the solar system together?
Our Sun – the heart of our solar system – is a yellow dwarf star, a hot ball of glowing gases. Its gravity holds the solar system together, keeping everything from the biggest planets to the smallest particles of debris in its orbit.
Are there any clues to the formation of the Solar System?
Fortunately, vital clues are scattered throughout the solar system — from the oldest rocks on the Earth, Earth’s Moon, Mars and the asteroids to the frozen outer reaches of the Kuiper Belt. NASA robotic missions are examining these distant worlds, making new discoveries that will help to fill in the pages of this story.
When did the story of the Solar System start?
Their story started even before our solar system formed 4.56 billion years ago. Their story started when the story started for every single thing in our universe. Our universe was born from the Big Bang about 13.5 billion years ago. The first stars lived out their lives and eventually exploded,…
How did the proto-sun form in the Solar System?
The cloud contracted under its own gravity and our proto-Sun formed in the hot dense center. The remainder of the cloud formed a swirling disk called the solar nebula. Within the solar nebula, scientists believe that dust and ice particles embedded in the gas moved, occasionally colliding and clumping together.
What was the composition of the early solar nebula?
Ongoing research is examining the early solar nebula’s composition and conditions such as radiation, by studying grains from comets, from the Sun, and the composition of Jupiter (for more information about comets, see Small Bodies / Big Impacts ).