Search results
Results from the WOW.Com Content Network
The visible-light (left) and infrared (right) views of the Trifid Nebula—a giant star-forming cloud of gas and dust located 5,400 light-years away in the constellation Sagittarius Stars are thought to form inside giant clouds of cold molecular hydrogen — giant molecular clouds roughly 300,000 times the mass of the Sun ( M ☉ ) and 20 ...
The nebular hypothesis says that the Solar System formed from the gravitational collapse of a fragment of a giant molecular cloud, [9] most likely at the edge of a Wolf-Rayet bubble. [10] The cloud was about 20 parsecs (65 light years) across, [9] while the fragments were roughly 1 parsec (three and a quarter light-years) across. [11]
A major difficulty was that, in this supposition, turbulent dissipation took place over the course of a single millennium, which did not give enough time for planets to form. The nebular hypothesis was first proposed in 1734 by Swedish scientist Emanuel Swedenborg [6] and later expanded upon by Prussian philosopher Immanuel Kant in 1755.
The compact object that was created after the explosion lies in the center of the Crab Nebula and its core is now a neutron star. Still other nebulae form as planetary nebulae . This is the final stage of a low-mass star's life, like Earth's Sun. Stars with a mass up to 8–10 solar masses evolve into red giants and slowly lose their outer ...
1796 – Pierre Laplace re-states the nebular hypothesis for the formation of the Solar System from a spinning nebula of gas and dust. [125] 1798 – Henry Cavendish accurately measures the gravitational constant in the laboratory, which allows the mass of the Earth to be derived, and hence the masses of all bodies in the Solar System. [126]
1965 – Penrose discovers the structure of the light cones in gravitational plane wave spacetimes. 1965 – Ezra Newman and others introduce Kerr-Newman metric. [152] [153] 1965 – Arno Penzias and Robert Wilson accidentally discover the cosmic microwave background radiation. [154] This rules out the steady-state model of Fred Hoyle and ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
It was composed of hydrogen and helium created shortly after the Big Bang 13.8 Ga (billion years ago) and heavier elements ejected by supernovae. About 4.5 Ga, the nebula began a contraction that may have been triggered by the shock wave from a nearby supernova. [23] A shock wave would have also made the nebula rotate.