Stellar Evolution
... • If a protostar forms with a mass less than 0.08 solar masses, its internal temperature never reaches a value high enough for thermonuclear fusion to begin. • This failed star is called a brown dwarf, halfway between a planet (like Jupiter) and a star. ...
... • If a protostar forms with a mass less than 0.08 solar masses, its internal temperature never reaches a value high enough for thermonuclear fusion to begin. • This failed star is called a brown dwarf, halfway between a planet (like Jupiter) and a star. ...
High School Science Proficiency Review #2 Earth Science
... C. Some types of electromagnetic radiation from stars are all galaxies are moving away from us? absorbed by Earth’s atmosphere. A. The once‐smaller universe is expanding in all direc‐ D. Some of the light being sent out from telescopes can be ...
... C. Some types of electromagnetic radiation from stars are all galaxies are moving away from us? absorbed by Earth’s atmosphere. A. The once‐smaller universe is expanding in all direc‐ D. Some of the light being sent out from telescopes can be ...
Sample pages 2 PDF
... the earth indicates that, approximately 14 billion years ago (the exact time remains in some dispute) the universe as we observe it was confined to a very small region of space and has been expanding from that confined space ever since (the ‘Big Bang’) (More precisely, the space itself has been expa ...
... the earth indicates that, approximately 14 billion years ago (the exact time remains in some dispute) the universe as we observe it was confined to a very small region of space and has been expanding from that confined space ever since (the ‘Big Bang’) (More precisely, the space itself has been expa ...
The Big Bang
... According to the big bang theory, what did the small sphere in the figure to the left contain? After the big bang, what happened to the matter that was released? Why do scientists now believe that the matter that exploded out of the big bang did not distribute itself evenly throughout the universe? ...
... According to the big bang theory, what did the small sphere in the figure to the left contain? After the big bang, what happened to the matter that was released? Why do scientists now believe that the matter that exploded out of the big bang did not distribute itself evenly throughout the universe? ...
Document
... find the exam with your name on it bring ID, calculator, and pencil there will be about 80 questions on the final exam ...
... find the exam with your name on it bring ID, calculator, and pencil there will be about 80 questions on the final exam ...
Nuclear Physics, Chemistry and Notation
... A nucleus X contains a protons (Note that once you know a, you look up what symbol to use for X; i.e. a and X give the same information.), b neutrons and has c bound electrons. It is written as a+b +(a−c) a X ...
... A nucleus X contains a protons (Note that once you know a, you look up what symbol to use for X; i.e. a and X give the same information.), b neutrons and has c bound electrons. It is written as a+b +(a−c) a X ...
Document
... From gas to dust to planets: Formation of our Solar System: The chemical elements formed in the interiors of stars. Dying stars ejected material into interstellar space, and presolar grains and amorphous material condensed in stellar atmospheres of stars such as Red Giants, AGB stars, and supernova ...
... From gas to dust to planets: Formation of our Solar System: The chemical elements formed in the interiors of stars. Dying stars ejected material into interstellar space, and presolar grains and amorphous material condensed in stellar atmospheres of stars such as Red Giants, AGB stars, and supernova ...
AY 12 Homework #4 Solutions Winter 2016 Longer Problems 1. a
... d) A star with M < 2 M burns hydrogen via the pp-chain. In addition, it experiences a helium flash in its core at the start of helium burning. A star above 2 M burns hydrogen via the CNO cycle. Such a star is also able to transition to helium burning smoothly because its core is not degenerate. e) ...
... d) A star with M < 2 M burns hydrogen via the pp-chain. In addition, it experiences a helium flash in its core at the start of helium burning. A star above 2 M burns hydrogen via the CNO cycle. Such a star is also able to transition to helium burning smoothly because its core is not degenerate. e) ...
How the univ works
... 14. A neutron star that spins and radiates energy is called a ____________. ...
... 14. A neutron star that spins and radiates energy is called a ____________. ...
Document
... spontaneously into space at high speeds. Alpha Particle = 2 protons and 2 neutrons Beta Particle = electron Gamma Ray = electromagnetic wave. All three types of radiation are ionizing (dislodge electrons and cause chemical reactions to happen) ...
... spontaneously into space at high speeds. Alpha Particle = 2 protons and 2 neutrons Beta Particle = electron Gamma Ray = electromagnetic wave. All three types of radiation are ionizing (dislodge electrons and cause chemical reactions to happen) ...
The Life and Death of Stars
... It has been doing this for 4.5 billion years Has enough Hydrogen in the core for 5 billion years What happens when all the core hydrogen is burnt? – the core will collapse, become denser and hotter – Helium starts to fuse into Carbon and Oxygen ...
... It has been doing this for 4.5 billion years Has enough Hydrogen in the core for 5 billion years What happens when all the core hydrogen is burnt? – the core will collapse, become denser and hotter – Helium starts to fuse into Carbon and Oxygen ...
Life in the Universe
... Life elsewhere in the Universe must resemble that present on Earth, because no other basis for life can exist! ...
... Life elsewhere in the Universe must resemble that present on Earth, because no other basis for life can exist! ...
Death of High Mass Stars
... • After core has a mass greater than 1.4 M (Chandrasekhar limit) the electron degeneracy is not strong enough. • Electrons are forced to combine with the protons to create neutrons. • Core collapses until pressure from physical force of neutrons bouncing against each other stops it. • Core rebounds ...
... • After core has a mass greater than 1.4 M (Chandrasekhar limit) the electron degeneracy is not strong enough. • Electrons are forced to combine with the protons to create neutrons. • Core collapses until pressure from physical force of neutrons bouncing against each other stops it. • Core rebounds ...
Supernovae: Heavy Elements
... 1% of all stellar mass is from supernova explosions Supernova explosions could easily be responsible for all of the iron and other heavy elements found in the galaxy Our sun, our planets, the silicon in our rocks, the change in our pockets, and the metal in the little green men’s spaceships, are all ...
... 1% of all stellar mass is from supernova explosions Supernova explosions could easily be responsible for all of the iron and other heavy elements found in the galaxy Our sun, our planets, the silicon in our rocks, the change in our pockets, and the metal in the little green men’s spaceships, are all ...
SCE 18 – Part 10
... • If we run this “backwards” we see that at earlier times, galaxies must have been closer together. • Eventually the distance would approach zero. • Would occur about 13-14 thousand million years ago. • Colloquially, this event is known as the “Big Bang” after Fred Hoyle. Georges Lemaître called it ...
... • If we run this “backwards” we see that at earlier times, galaxies must have been closer together. • Eventually the distance would approach zero. • Would occur about 13-14 thousand million years ago. • Colloquially, this event is known as the “Big Bang” after Fred Hoyle. Georges Lemaître called it ...
Birth of Elements
... with a bang, with matter and radiation being created, or at a time when stars began to shine? Telling both stories would make this article too long and so I will confine myself to an account of stellar nucleo-synthesis. We assume a period of time when matter and radiation have been created and when ...
... with a bang, with matter and radiation being created, or at a time when stars began to shine? Telling both stories would make this article too long and so I will confine myself to an account of stellar nucleo-synthesis. We assume a period of time when matter and radiation have been created and when ...
the free PDF resource
... usually yellow, white or blue depending on temperature (hotter = more blue) mass varies hugely usually orbited by planets sometimes exists in a pair (called binary system) almost entirely hydrogen. ...
... usually yellow, white or blue depending on temperature (hotter = more blue) mass varies hugely usually orbited by planets sometimes exists in a pair (called binary system) almost entirely hydrogen. ...
Distribution of Elements in the Earth`s Crust
... space. Over time, hydrogen and helium particles coalesced into dense clouds, or nebulae, of contracting gas, which eventually formed the first stars. As the atoms in these stars were crushed under the enormous pressure generated by their mutual gravitation, their cores reached temperatures of many m ...
... space. Over time, hydrogen and helium particles coalesced into dense clouds, or nebulae, of contracting gas, which eventually formed the first stars. As the atoms in these stars were crushed under the enormous pressure generated by their mutual gravitation, their cores reached temperatures of many m ...
123mt13-2a
... Two hydrogen atoms combine to form a molecule (red herring) Two hydrogen atoms collide – 3 points for this because this can happen but it does not “occur whenever” A hydrogen atom captures and electron (unphysical process) A hydrogen atom absorbs a red photon (red photons have insufficient energy to ...
... Two hydrogen atoms combine to form a molecule (red herring) Two hydrogen atoms collide – 3 points for this because this can happen but it does not “occur whenever” A hydrogen atom captures and electron (unphysical process) A hydrogen atom absorbs a red photon (red photons have insufficient energy to ...
Chemical Universe. - University of Texas Astronomy
... art of Sneden’s work is helping to figure out what events influenced the chemical makeup of the present-day galaxy. The fact that the oldest stars contain more europium (an r-process element made in supernovae) than barium (an s-process element), for example, means that the early formation of elemen ...
... art of Sneden’s work is helping to figure out what events influenced the chemical makeup of the present-day galaxy. The fact that the oldest stars contain more europium (an r-process element made in supernovae) than barium (an s-process element), for example, means that the early formation of elemen ...
Metal Abundances of Subdwarf B Stars from SPY
... Metal Abundances of Subdwarf B Stars from SPY – a ...
... Metal Abundances of Subdwarf B Stars from SPY – a ...
lab 14B - atomic challenge
... All the elements were created in the super-hot cores of stars. Stars get their energy by combining hydrogen atoms together to make other elements, such as helium. Along the way, a few protons get converted into neutrons and electrons. In this investigation, you will learn how these subatomic particl ...
... All the elements were created in the super-hot cores of stars. Stars get their energy by combining hydrogen atoms together to make other elements, such as helium. Along the way, a few protons get converted into neutrons and electrons. In this investigation, you will learn how these subatomic particl ...
Quantum Tunneling
... energy, was not the escape of a single proton, but of a helium nucleus--two protons and two neutrons bound together by the nuclear force, a very strong bond. Such ...
... energy, was not the escape of a single proton, but of a helium nucleus--two protons and two neutrons bound together by the nuclear force, a very strong bond. Such ...
Where do we come from?
... If the universe had remained dense, it wouldn’t have cooled enough for nuclei, atoms, galaxies, and us to form. (Speaking to an audience of humans, I make no apologies ...
... If the universe had remained dense, it wouldn’t have cooled enough for nuclei, atoms, galaxies, and us to form. (Speaking to an audience of humans, I make no apologies ...
Nucleosynthesis
Nucleosynthesis is the process that creates new atomic nuclei from pre-existing nucleons, primarily protons and neutrons. The first nuclei were formed about three minutes after the Big Bang, through the process called Big Bang nucleosynthesis. It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos.With the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that continues today. Some of these elements, particularly those lighter than iron, continue to be delivered to the interstellar medium when low mass stars eject their outer envelope before they collapse to form white dwarfs. The remains of their ejected mass form the planetary nebulae observable throughout our galaxy.Supernova nucleosynthesis within exploding stars by fusing carbon and oxygen is responsible for the abundances of elements between magnesium (atomic number 12) and nickel (atomic number 28). Supernova nucleosynthesis is also thought to be responsible for the creation of rarer elements heavier than iron and nickel, in the last few seconds of a type II supernova event. The synthesis of these heavier elements absorbs energy (endothermic) as they are created, from the energy produced during the supernova explosion. Some of those elements are created from the absorption of multiple neutrons (the R process) in the period of a few seconds during the explosion. The elements formed in supernovas include the heaviest elements known, such as the long-lived elements uranium and thorium.Cosmic ray spallation, caused when cosmic rays impact the interstellar medium and fragment larger atomic species, is a significant source of the lighter nuclei, particularly 3He, 9Be and 10,11B, that are not created by stellar nucleosynthesis.In addition to the fusion processes responsible for the growing abundances of elements in the universe, a few minor natural processes continue to produce very small numbers of new nuclides on Earth. These nuclides contribute little to their abundances, but may account for the presence of specific new nuclei. These nuclides are produced via radiogenesis (decay) of long-lived, heavy, primordial radionuclides such as uranium and thorium. Cosmic ray bombardment of elements on Earth also contribute to the presence of rare, short-lived atomic species called cosmogenic nuclides.