The Birth of a Solar System The history

The Birth of a Solar System The history of our Solar System began about 13. 7 billion years ago with the Big Bang creation event. This provided the elements, along with later material from former stars, to form the solar system. Scientists now believe that our Milky Way galaxy was formed very early in the history of the Universe, perhaps as early as 950 million to 1 billion ABB. Our solar system, however, took another 8 billion years or so to form.

The Protoplanetary Disk Model A protoplanetary disk is a circumstellar disk of matter, including gas and dust, from which planets may eventually form or be in the process of forming.

The Protoplanetary Disk Model The existence of such disks was long suspected, but was confirmed by direct imaging in 1994 when C. Robert O'Dell and colleagues of Rice University used the Hubble Space Telescope (HST) to examine newborn stars in the Orion Nebula. About half of those were found to be surrounded by disks of gas and dust.

The Protoplanetary Disk Model Also in 1994, John Stauffer and associates of the Harvard -Smithsonian Center for Astrophysics reported that 70 to 80 percent of infant stars at the center of the Orion Nebula showed signs of having disks. This high fraction has since been confirmed by more sensitive observations by the Infrared Space Observatory.

The Protoplanetary Disk Model The heavier elements were formed in many earlier stars and supernovas. Dust, gas and chemical compounds began to concentrate in a region of space. Supernova shockwaves helped to “clump” the matter. A large, rotating nebula began to form. As a result of Thegravitational protosun became a star. Thethe solar contraction, spin ignition flare-up may rate increased. Most have blown away the mass concentrated in hydrogen and helium the central proto-star. atmospheres of inner The remaining planets. The material formed an protoplanets heated, accretion disk. separating heavy. The and light minerals. Larger material in the bodies cooled slower, accretion disk began heavy materials towith clump. The nebula settling longer began toover contract times into central about 5 billion years cores. ago.

The Protoplanetary Disk Model http: //www. daviddarling. info/encycl opedia/P/protoplandisk. html

The Protoplanetary Disk Model http: //www. youtube. com/watch? v=3 Ymeaj. E-TT 8 http: //www. youtube. com/watch? v=T Uj. JTNKO 9 FU