Why is the Oort Cloud important for understanding the formation of the solar system?
The Oort cloud is far enough away that the gravitational influence of passing stars can perturb a comet’s orbit. A comet headed toward the inner solar system could hit the Sun or impact a planet. Or it could be “caught” by an interaction with one of the giant planets to become a really short-period comet.
What is the evidence for the existence of the Oort cloud?
Answer: There is what one could call “indirect observational evidence for the Oort Cloud. It has been known since 1932 (first proposed by Ernst Opik, then updated by Jan Oort in 1950) that one needs a source for long-period comets that is beyond the orbit of Pluto.
What are four key features of our solar system that any theory of solar system formation?
What are four key features of our solar system that any theory of solar system formation must be able to explain? There are vast numbers of asteroids and comets. There are clear patterns to the rotation and orbits of large bodies in the solar system. There are a few notable “exceptions to the rules.”
What property of our solar system must a formation theory explain?
What properties of our solar system must a formation theory explain? – Rotation of Uranus, Earth’s Moon, etc. States that our solar system formed from the gravitational collapse of a giant interstellar gas cloud—the solar nebula. You just studied 21 terms!
How does the nebular theory explain the formation of our solar system?
Currently the best theory is the Nebular Theory . This states that the solar system developed out of an interstellar cloud of dust and gas, called a nebula . Most likely the next step was that the nebula flattened into a disk called the Protoplanetary Disk ; planets eventually formed from and in this disk.
What are the theories of the formation of the solar system?
The Modern Laplacian theory French astronomer and mathematician Pierre-Simon Laplace first suggested in 1796 that the Sun and the planets formed in a rotating nebula which cooled and collapsed. The theory argued that this nebula condensed into rings, which eventually formed the planets and a central mass – the Sun.
What are the major phases of solar system formation?
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.
What are the 3 theories of the solar system?
Find out more below.
- The Accretion theory. The Sun passes through a dense interstellar cloud and emerges surrounded by a dusty, gaseous envelope.
- The Protoplanet theory. A dense interstellar cloud produces a cluster of stars.
- The Capture theory.
What are the five steps of the nebular hypothesis?
Terms in this set (5)
- step one(4) -The solar nebula consisted of. -hydrogen,
- step two(2) -A disturbance.
- step three(2) -The solar nebula assumed a flat, disk shape.
- step four(2) -Inner planets began to form from metallic.
- step five(2) -Larger outer planets began forming from fragments.
What is the meaning of nebular hypothesis?
Our solar system formed at the same time as our Sun as described in the nebular hypothesis. The nebular hypothesis is the idea that a spinning cloud of dust made of mostly light elements, called a nebula, flattened into a protoplanetary disk, and became a solar system consisting of a star with orbiting planets [12].
What is the correct order of formation within the nebular hypothesis?
1) The solar system begins as a cloud of dust and gas (nebula) 2) Nebula rotates and collapses toward the center of the cloud. 3) Heat and pressure is generated at the center forming the Sun. 4) A disk of gas and dust spins around the Sun and particles clump together to form planets (Protoplanetary Disk)
What is the order of the nebular hypothesis?
According to this theory, the Sun and all the planets of our Solar System began as a giant cloud of molecular gas and dust. Then, about 4.57 billion years ago, something happened that caused the cloud to collapse.
Why is the nebular hypothesis accepted?
This theory is widely accepted to account for the formation of stars and planetary systems such as ours. The first version of the nebular hypothesis was proposed in 1755 by the German philosopher Immanuel Kant and modified in 1796 by Pierre Laplace.
What are the evidences that support the nebular hypothesis?
Comets, asteroids, and meteorites recovered on Earth also provide a number of clues and evidence of Nebular-type development. And the motions of most solar system objects orbit and rotate in an organized fashion. There are a few exceptions to what we would expect to find.
Why was the nebular hypothesis rejected?
The main problem involved angular momentum distribution between the Sun and planets. The planets have 99% of the angular momentum, and this fact could not be explained by the nebular model. As a result, astronomers largely abandoned this theory of planet formation at the beginning of the 20th century.
What were some early ideas about the formation of our solar system?
The most widely accepted theory of planetary formation is known as the nebular hypothesis. This theory mentioned that, 4.6 billion years ago, the Solar System was formed by the gravitational collapse of a giant molecular cloud spanning several light-years.
What is the Kant Laplace nebular hypothesis?
The Kant-Laplace nebular hypothesis Kant’s central idea was that the solar system began as a cloud of dispersed particles. He assumed that the mutual gravitational attractions of the particles caused them to start moving and colliding, at which point chemical forces kept them bonded together.
What are the six stages of the nebular theory?
- Nebula, protosun forming, spinning planetary disk, protoplanets forming,
- Shock waves from a nearby supernova explosion.
- It also begins to flatten.
- Protosun.
- When the gravitational forces begin to fuse hydrogen into helium (fusion)
- Protoplanets.
- Inner protoplanets – most of their lightweight gases are boiled away,
What are the 4 characteristics of terrestrial planets?
Terrestrial planets also have a molten heavy-metal core, few moons and topological features such as valleys, volcanoes and craters. In our solar system, there are four terrestrial planets, which also happen to be the four closest to the sun: Mercury, Venus, Earth and Mars.
What force keeps all the planets in their orbits?
gravity
What is the meaning of planetesimals?
planetesimal. [ plăn′ĭ-tĕs′ə-məl ] Any of innumerable small bodies of accreted gas and dust thought to have orbited the Sun during the formation of the planets.
How did the inner and outer planets form?
The temperature of the early solar system explains why the inner planets are rocky and the outer ones are gaseous. As the gases coalesced to form a protosun, the temperature in the solar system rose. There were relatively few elements of any other kind in a solid state to form the inner planets.
What role do planetesimals play in the origin of the planets?
A planetesimal is small bodies from which a planet originated in the early stages of formation of the solar system. Because they formed in the cooler region of the solar nebula and therefore did not loose their lighter gases. Because they have their gases they are not as dense as the inner planets.
What is a planetesimal What was the role of planetesimals in the formation of planets?
According to the planetesimal hypothesis, when a planetary system is forming, there is a protoplanetary disk with materials from the nebulae from which the system came. This material is gradually pulled together by gravity to form small chunks. Some of these planetesimals go on to become planets and moons.
What is the planetesimal theory of the formation of the planets?
A widely accepted theory of planet formation, the so-called planetesimal hypotheses, the Chamberlin–Moulton planetesimal hypothesis and that of Viktor Safronov, states that planets form from cosmic dust grains that collide and stick to form ever-larger bodies.
Which event led to the formation of our 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.
How do planetesimals form 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.
How do we find planets?
Another method astronomers use to find planets is called gravitational microlensing. It works by carefully measuring the brightness of one star as it passes in front of another. The foreground star acts like a lens, focusing the light with its gravity and causing the star to brighten for a few hours.
What are the planets in our solar system made of?
Earth and the other three inner planets of our solar system (Mercury, Venus and Mars) are made of rock, containing common minerals like feldspars and metals like magnesium and aluminum. So is Pluto. The other planets are not solid. Jupiter, for instance, is made up mostly of trapped helium, hydrogen, and water.
What are the Jovian planets?
Jupiter, Saturn, Uranus and Neptune collectively make up the group known as the jovian planets. The general structures of the jovian planets are opposite those of the terrestrial planets.