Here
... protons) combine to form 1 helium nucleus (which has two protons and two neutrons). • The details are a bit complex: In the Sun, 6 hydrogen nuclei are involved in a sequence that produces two hydrogen nuclei and one helium nucleus. This is the proton-proton chain. In more massive stars, a carbon ...
... protons) combine to form 1 helium nucleus (which has two protons and two neutrons). • The details are a bit complex: In the Sun, 6 hydrogen nuclei are involved in a sequence that produces two hydrogen nuclei and one helium nucleus. This is the proton-proton chain. In more massive stars, a carbon ...
It all began with a Big Bang!
... hotter and denser than anything we can imagine. Then it suddenly exploded. The Universe that we know was born. In a fraction of a second, the Universe grew from smaller than a single atom to bigger than a galaxy. It is still expanding today. ...
... hotter and denser than anything we can imagine. Then it suddenly exploded. The Universe that we know was born. In a fraction of a second, the Universe grew from smaller than a single atom to bigger than a galaxy. It is still expanding today. ...
It`s time to eat humble pie: latest evidence gives humans a
... than the mass of our sun, the gravity will be so strong that the star collapses in on itself, forming a tightly packed ‘‘white dwarf’’. Stars of even greater mass, between eight and 25 times that of the sun, are subject to even stronger forces of gravity and these form neutron stars. Any larger, and ...
... than the mass of our sun, the gravity will be so strong that the star collapses in on itself, forming a tightly packed ‘‘white dwarf’’. Stars of even greater mass, between eight and 25 times that of the sun, are subject to even stronger forces of gravity and these form neutron stars. Any larger, and ...
Review for Astronomy 3 Midterm #2
... Novae occur in systems consisting of a white dwarf with a main sequence/red giant companion. The white dwarf will sometimes “steal matter” from its companion, and eventually will have enough hydrogen on its surface for that hydrogen to begin to fuse to helium. It will do this very quickly and then ...
... Novae occur in systems consisting of a white dwarf with a main sequence/red giant companion. The white dwarf will sometimes “steal matter” from its companion, and eventually will have enough hydrogen on its surface for that hydrogen to begin to fuse to helium. It will do this very quickly and then ...
astrocoursespring2012lec2-6
... Stars with lower masses comprise the yellow, orange, and red dwarfs on the lower-right part of the main sequence, where they remain for billions of years. As a star begins to exhaust the hydrogen fuel in its core, it evolves away from the main sequence toward the upper right and becomes a red giant ...
... Stars with lower masses comprise the yellow, orange, and red dwarfs on the lower-right part of the main sequence, where they remain for billions of years. As a star begins to exhaust the hydrogen fuel in its core, it evolves away from the main sequence toward the upper right and becomes a red giant ...
When radiation ruled
... Key idea: When the universe was smaller (when the distance between us and some object was smaller), the temperature was hotter. There is no obvious limit to the temperature. Events in the universe’s life, when the universe was smaller & hotter. Production of the first nuclei other than H (3min) ( Re ...
... Key idea: When the universe was smaller (when the distance between us and some object was smaller), the temperature was hotter. There is no obvious limit to the temperature. Events in the universe’s life, when the universe was smaller & hotter. Production of the first nuclei other than H (3min) ( Re ...
Untitled
... to create the element beryllium. Bery Ilium lives for 10- 16 (0.0000000000000001) seconds before it disintegrates, but during that time, it can combine with another helium to make carbon. In essence, three heliums collide practically slmuttaneously, in what's called the triple alpha process, to make ...
... to create the element beryllium. Bery Ilium lives for 10- 16 (0.0000000000000001) seconds before it disintegrates, but during that time, it can combine with another helium to make carbon. In essence, three heliums collide practically slmuttaneously, in what's called the triple alpha process, to make ...
Atoms and Elements
... • Once a star starts producing iron-56, any further fusion reactions consume energy. The star either becomes a white dwarf, or, if the star was large enough, the core collapses, and the outer layers of the star explode in a supernova. • The core forms a neutron star, with a mass of 1.4 times that of ...
... • Once a star starts producing iron-56, any further fusion reactions consume energy. The star either becomes a white dwarf, or, if the star was large enough, the core collapses, and the outer layers of the star explode in a supernova. • The core forms a neutron star, with a mass of 1.4 times that of ...
Components of the Universe Test Review
... can travel through a vacuum 3. smaller units, such as kilometers, result in values that are impractical and large 4. many objects in the universe radiate light that can be seen from Earth ...
... can travel through a vacuum 3. smaller units, such as kilometers, result in values that are impractical and large 4. many objects in the universe radiate light that can be seen from Earth ...
Mon Oct 28, 2013 MOON AND MARS IN PREDAWN SKY Tonight
... Tonight the moon rises shortly before three in the morning, while Mars comes up a little after 3. By 4 am you can find the red planet off to the left of the moon and slightly below it. Although they appear right next to each other, these two celestial objects are in different constellations: Mars is ...
... Tonight the moon rises shortly before three in the morning, while Mars comes up a little after 3. By 4 am you can find the red planet off to the left of the moon and slightly below it. Although they appear right next to each other, these two celestial objects are in different constellations: Mars is ...
Lecture 4 Hydrostatic equilibrium
... the star. Hence changes that involve substantial losses or gains of energy can not take place on timescales shorter than ...
... the star. Hence changes that involve substantial losses or gains of energy can not take place on timescales shorter than ...
Astronomy 100, Fall 2006 Name: Due: December 5, 2006 at 11 a.m.
... do with the distribution of globular clusters in this galaxy? ...
... do with the distribution of globular clusters in this galaxy? ...
New ultra faint dwarf galaxy candidates discovered with the Dark
... velocities and 'Dynamical Mass' of this candidate: J0335' Once dynamical mass is known, then can be added to the sum of all known dwarfs, and we can see if we can answer confirm (or deny) that dark matter is a possible source for gamma rays in the galactic center. ...
... velocities and 'Dynamical Mass' of this candidate: J0335' Once dynamical mass is known, then can be added to the sum of all known dwarfs, and we can see if we can answer confirm (or deny) that dark matter is a possible source for gamma rays in the galactic center. ...
File
... 1. Nebula or stellar nursery- a star is born in a large cloud of dust and gas. As the star spins and becomes hotter, a protostar is formed. 2. Main Sequence Star-The star gives off light and heat for thousands of millions of years. 3. Red Giant-Near the end of its life, the star swells into a huge r ...
... 1. Nebula or stellar nursery- a star is born in a large cloud of dust and gas. As the star spins and becomes hotter, a protostar is formed. 2. Main Sequence Star-The star gives off light and heat for thousands of millions of years. 3. Red Giant-Near the end of its life, the star swells into a huge r ...
Chapter 25.2 - Planet Earth
... tons. Densities this great are possible only when electrons are displaced inward from their regular orbits, around an atom’s nucleus, allowing the atoms to take up less than the “normal” amount of space. Material in this state is called degenerate matter. In degenerate matter, the atoms have been sq ...
... tons. Densities this great are possible only when electrons are displaced inward from their regular orbits, around an atom’s nucleus, allowing the atoms to take up less than the “normal” amount of space. Material in this state is called degenerate matter. In degenerate matter, the atoms have been sq ...
I`m using this stupid huge font
... Some current data suggest that life on Earth might have originated deep underground, independent of sunlight, so that life could arise on frozen planets across the Galaxy. ...
... Some current data suggest that life on Earth might have originated deep underground, independent of sunlight, so that life could arise on frozen planets across the Galaxy. ...
sun.galaxy.notes
... But what determines the size of a star? Gravity wants to crush the star So why doesn’t it? Because the outward pressure Or force of energy from Fusion balances out the inward force of gravity This keeps the star in a state of balance or equilibrium! ...
... But what determines the size of a star? Gravity wants to crush the star So why doesn’t it? Because the outward pressure Or force of energy from Fusion balances out the inward force of gravity This keeps the star in a state of balance or equilibrium! ...
Star Clusters and Stellar Dynamics
... energy by an amount equal to the mean energy; or the time to change its velocity vector by ~ 90 deg. • There will be a few strong encounters, and lots of weak ones. Their effects can be estimated through Coulomlike scattering ...
... energy by an amount equal to the mean energy; or the time to change its velocity vector by ~ 90 deg. • There will be a few strong encounters, and lots of weak ones. Their effects can be estimated through Coulomlike scattering ...
Star Formation in the Galactic Center
... stars…..Would over produce massive stars that are not seen. In situ: only need to suppress low-mass by 10% or so. Could indicate IMF is not universal….especially in extreme cases involving BHs. ...
... stars…..Would over produce massive stars that are not seen. In situ: only need to suppress low-mass by 10% or so. Could indicate IMF is not universal….especially in extreme cases involving BHs. ...
What keeps stars shining? What holds them up? Lecture 14. The
... • Why does the main sequence luminosity increase so rapidly with mass? The central temperature of more massive stars must be higher to support additional material. The Hydrogen fusion rate is very sensitive to the star's central temperature. • Main sequence stars are especially stable because of the ...
... • Why does the main sequence luminosity increase so rapidly with mass? The central temperature of more massive stars must be higher to support additional material. The Hydrogen fusion rate is very sensitive to the star's central temperature. • Main sequence stars are especially stable because of the ...
The Life Cycles of Stars
... mass of a star, in addition, decides the temperature of a star’s core each time it goes into a period of flexion. Depending on the stage in a star’s development, various elements are formed within the core of the star, with the heaviest sustainable material being iron, when a massive star forms an i ...
... mass of a star, in addition, decides the temperature of a star’s core each time it goes into a period of flexion. Depending on the stage in a star’s development, various elements are formed within the core of the star, with the heaviest sustainable material being iron, when a massive star forms an i ...
File - YEAR 11 EBSS PHYSICS DETAILED STUDIES
... sun. In doing so, they have been able come up with ‘facts’ about our sun. (These facts are all theoretical as it is impossible to test them) These facts include: Fusion occurs within 0.25R where temperatures reach above 10 million degrees. Radiative diffusion is the main mechanism for energy tran ...
... sun. In doing so, they have been able come up with ‘facts’ about our sun. (These facts are all theoretical as it is impossible to test them) These facts include: Fusion occurs within 0.25R where temperatures reach above 10 million degrees. Radiative diffusion is the main mechanism for energy tran ...
How is Light Made?
... • Obtained by integrating Planck’s Law over λ • Luminosity is proportional to T4 ⇒ small increase in temperature produces big increase in luminosity ...
... • Obtained by integrating Planck’s Law over λ • Luminosity is proportional to T4 ⇒ small increase in temperature produces big increase in luminosity ...
Main sequence
In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hertzsprung and Henry Norris Russell. Stars on this band are known as main-sequence stars or ""dwarf"" stars.After a star has formed, it generates thermal energy in the dense core region through the nuclear fusion of hydrogen atoms into helium. During this stage of the star's lifetime, it is located along the main sequence at a position determined primarily by its mass, but also based upon its chemical composition and other factors. All main-sequence stars are in hydrostatic equilibrium, where outward thermal pressure from the hot core is balanced by the inward pressure of gravitational collapse from the overlying layers. The strong dependence of the rate of energy generation in the core on the temperature and pressure helps to sustain this balance. Energy generated at the core makes its way to the surface and is radiated away at the photosphere. The energy is carried by either radiation or convection, with the latter occurring in regions with steeper temperature gradients, higher opacity or both.The main sequence is sometimes divided into upper and lower parts, based on the dominant process that a star uses to generate energy. Stars below about 1.5 times the mass of the Sun (or 1.5 solar masses (M☉)) primarily fuse hydrogen atoms together in a series of stages to form helium, a sequence called the proton–proton chain. Above this mass, in the upper main sequence, the nuclear fusion process mainly uses atoms of carbon, nitrogen and oxygen as intermediaries in the CNO cycle that produces helium from hydrogen atoms. Main-sequence stars with more than two solar masses undergo convection in their core regions, which acts to stir up the newly created helium and maintain the proportion of fuel needed for fusion to occur. Below this mass, stars have cores that are entirely radiative with convective zones near the surface. With decreasing stellar mass, the proportion of the star forming a convective envelope steadily increases, whereas main-sequence stars below 0.4 M☉ undergo convection throughout their mass. When core convection does not occur, a helium-rich core develops surrounded by an outer layer of hydrogen.In general, the more massive a star is, the shorter its lifespan on the main sequence. After the hydrogen fuel at the core has been consumed, the star evolves away from the main sequence on the HR diagram. The behavior of a star now depends on its mass, with stars below 0.23 M☉ becoming white dwarfs directly, whereas stars with up to ten solar masses pass through a red giant stage. More massive stars can explode as a supernova, or collapse directly into a black hole.