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Astronomy Test Objective 1: Origins of the Universe Multiple Choice
Astronomy Test Objective 1: Origins of the Universe Multiple Choice

... b. end up with a smaller mass. c. continue to fuse iron in its core. d. become a neutron star. Matching Match each item with the correct phrase below. a. black hole b. fusion c. main sequence d. nebula e. spectrum 4. Combining of lightweight nuclei into heavier nuclei, such as four hydrogen nuclei c ...
GEARS Workshop Monday - Georgia Southern University
GEARS Workshop Monday - Georgia Southern University

... The Chandra data shows bright X-ray sources in this field, most of which are young stars. In this image, red, green, and blue represent low, medium, and high energy X-rays. The Chandra data have been overlaid on the Hubble Space Telescope image to show the context of these X-ray data. Very few X-ray ...
Beyond the Solar System Homework for Geology 8
Beyond the Solar System Homework for Geology 8

... 46. Only the most massive stars evolve to become black holes. 47. Hot stars evolve much more rapidly than do cool stars. 48. Degenerate matter is highly condensed material, where even the electrons of atoms are pushed in, towards the center or nucleus of the atoms. 49. Pulsars are a type of neutron ...
E1 Introduction to the universe
E1 Introduction to the universe

... Once the hydrogen in the core is used up, contraction will occur. This causes T↑ This causes outer layers to expand. The surface temperature drops, but the luminosity increases due to greater surface area! The helium in the core fuses into oxygen and carbon…. They fuse to form silicon. The helium in ...
Chapter 25.2 - Planet Earth
Chapter 25.2 - Planet Earth

CARBON STARS
CARBON STARS

... have a wide range of variability, from Miratypes with periods of hundreds of days to Cepheid-types with periods of a handful of days • Many semi-irregular types also observed ...
this article as a PDF
this article as a PDF

Astronomy
Astronomy

... If stars rotate with periods of tens of days, why does a neutron star rotate several to thousands of times a second? A. When a neutron star collapses, the intensified magnetic field causes it to rotate much more quickly. B. When a neutron star collapses, its rotation is kicked up by the ejected mat ...
7/3 Some stars were found in regions above the main sequence
7/3 Some stars were found in regions above the main sequence

Lecture16
Lecture16

... We recently added two new spectral types to this list. The “L”s and “T”s. Their temperatures range from 2500 K down to 700 K. These types generally contain the very lowest mass stars and “brown dwarfs”. Brown dwarfs have so little mass, they cannot even start nuclear fusion. ...
Physics 102 Quiz 4 - Solutions March 21, 2003 1. (1) Which of the
Physics 102 Quiz 4 - Solutions March 21, 2003 1. (1) Which of the

microsoft word
microsoft word

Investigate Stars and Galaxies - American Museum of Natural History
Investigate Stars and Galaxies - American Museum of Natural History

a thermonuclear flame has almost completed TEN SECONDS AFTER IGNITION,
a thermonuclear flame has almost completed TEN SECONDS AFTER IGNITION,

... i ron ic a lly, the stars that are thought to blow up as type Ia supernovae are usually paragons of stability— namely, white dwarf stars. A white dwarf is the inert remnant of what used to be a sunlike star. If left unmolested, it stays more or less in the state it was born, gradually cooling down a ...
Beyond the Solar System Homework for Geology 8
Beyond the Solar System Homework for Geology 8

A Tale of Star and Planet Formation
A Tale of Star and Planet Formation

... Clusters (may be bound) ...
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www.if.ufrgs.br

... 1) Neutron stars in x-ray binaries 2) Mass-radius relationship ...
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Cold atomic matter in the Universe Circmstellar shells around

Volcanoes and Igneous Activity Earth - Chapter 4
Volcanoes and Igneous Activity Earth - Chapter 4

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PowerPoint Presentation - ASTR498E High energy

... The area under consideration must be oriented face-on to lineof-sight to the star In principle, this definition works for any kind of energy emitted by the star… most commonly, we mean e/m radiation Sometimes, it is useful to consider the observed flux in a restricted range of e/m wavelengths (e.g., ...
Fundamental Motions (PowerPoint)
Fundamental Motions (PowerPoint)

... The star paths are inclined The Pole Star stays in an unchanging location, due North Some southern stars are never seen by us, while some Northern stars never go below the northern horizon (including those in the Big Dipper, for us in Kingston) Southern stars rise in the Southeast, and follow short ...
Galaxies and the Big Bang Theory
Galaxies and the Big Bang Theory

... •Spiral galaxies contain ____________ and _____________. Elliptical Galaxies •Look like _______________ or __________________ ______________. •Billions of stars •Contain very little _________ and ________ between stars. ...
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ppt file

Constants and Equations
Constants and Equations

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I : Importance of binary stars

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Stellar evolution



Stellar evolution is the process by which a star changes during its lifetime. Depending on the mass of the star, this lifetime ranges from a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. The table shows the lifetimes of stars as a function of their masses. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more-massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.
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