* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Video review
Astronomical unit wikipedia , lookup
Aquarius (constellation) wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
Tropical year wikipedia , lookup
Astrobiology wikipedia , lookup
Definition of planet wikipedia , lookup
Directed panspermia wikipedia , lookup
IAU definition of planet wikipedia , lookup
Advanced Composition Explorer wikipedia , lookup
Planetary habitability wikipedia , lookup
Nebular hypothesis wikipedia , lookup
Extraterrestrial life wikipedia , lookup
Star formation wikipedia , lookup
Comparative planetary science wikipedia , lookup
Solar System wikipedia , lookup
Timeline of astronomy wikipedia , lookup
History of Solar System formation and evolution hypotheses wikipedia , lookup
Formation and evolution of the Solar System wikipedia , lookup
Birth of the Solar System 1. The first modern theory of the formation of planets and solar systems from a nebular cloud was proposed by philosopher Immanuel _________ in the 1700s. 2. A collapsing gas cloud (nebula) that form a star system increases its rotation rate because of the conservation of _________________ momentum. 3. The protostar is the early stage of a star that forms at the ____________ of the collapsing gas cloud. 4. The Sun formed in the center of the nebular cloud about ______billion years ago. 5. Elements heavier than hydrogen and helium are formed by ________________________. 6. Comet material was brought back to Earth by the _____________ spacecraft in 2006. 7. Particles within the collapsing solar nebula disk begin to collide and collect (accrete) from the _____________________ force. 8. Gravity takes over the formation of clumps in the early solar system when they reach the approximate size of ____________________. 9. Bodies in the solar system greater than about __________ km across are pulled into a spherical shape by gravity. 10. The Moon was most likely formed after the violent collision of a body the size of Mars with ______________. 11. The two moons of Mars, Phobos and Deimos, are thought to be captured ________________. 12. The solar system’s _____________ line is a boundary outside of which water is in a frozen state, allowing the giant gas and ice planets to form. 13. The blue-green color of the giant ice planet Uranus is due to an upper layer of __________________ gas. 14. The likely explanation of the Moon’s craters having the same age, the large number of icy bodies in the Kuiper belt, the motion of Neptune farther out in its orbit, and the scattering of asteroids throughout the solar system at the same time, was the occurrence of a resonance between the Jupiter-Neptune orbits approximately ______ billion years ago. 15. The Sun will end its life in about ______ billion years, expanding beyond the inner planets to form a red-giant star, then ending as a white dwarf.