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PHYS 200 - Understanding the Universe
PHYS 200 - Understanding the Universe

AyC10 Fall 2007: Midterm 2 Review Sheet
AyC10 Fall 2007: Midterm 2 Review Sheet

... High-mass stars have short lives and explode in supernovae before many other stars have even finished burning up their hydrogen. Therefore, only young clusters should contain high-mass stars. Old clusters won’t have any left. CS 169-196 Refer to the Supernovae worksheet for more material on this ran ...
Skywatch Astro Ed Dec13
Skywatch Astro Ed Dec13

... of other stars, then hurled into space as the stars died, where they could be incorporated into new stars. Population II stars formed when there were almost no heavier elements around, so they have only tiny amounts of them. But Population I stars, like the Sun, are younger, so they have higher prop ...
Support worksheet – Topic 3 Questions
Support worksheet – Topic 3 Questions

... State in what way Cepheid stars are different from other variable stars. ...
3A8d
3A8d

Powerpoint
Powerpoint

... b) by nucleosynthesis in massive stars. c) in the cores of stars like the Sun. d) within planetary nebulae. e) They have always existed. ...
Astronomy
Astronomy

... molecular hydrogen—giant molecular clouds (GMC). They are gravitationally unstable, and matter coalesces to smaller denser clumps within, which then proceed to collapse and form stars.  Star formation is a complex process, which always produces a gaseous protoplanetary disk around the young star. T ...
Chapter 30 Notes
Chapter 30 Notes

... As the planetary nebula disperses; gravity causes the remaining matter in the star to collapse inward until it cannot be pressed further together. A hot, extremely dense core of matter is left behind. This mass is called a white dwarf and can shine for billions of years before it cools completely. S ...
The Earth and Beyond
The Earth and Beyond

... If the light source is moving ___ from us we would find that the absorption lines are all _______ towards the ___ end of the spectrum (the longer wavelength end). The ________ the light source is moving the further its pattern is shifted. Light from the edge of the ______ also shows this pattern, so ...
Astronomy 120
Astronomy 120

... 1. Zeilik Study Exercise 16.1 In a short paragraph, describe the primary characteristics of a white dwarf? 2. Zeilik Study Exercise 16.2 In a short paragraph, describe to a friend who has not studied astronomy the chief features of a neutron star. 3. Zeilik Study Exercise 16.5 Assuming no loss of ma ...
Type I SuperNova
Type I SuperNova

... Nothing ...
A not so massive cluster hosting a very massive star
A not so massive cluster hosting a very massive star

... We present the first physical characterization of the young open cluster VVV CL041. We spectroscopically observed the cluster main-sequence stellar population and a very-massive star candidate: WR62-2. CMFGEN modelling to our near-infrared spectra indicates that WR62-2 is a very luminous (106.4±0.2 ...
star
star

... A special class of binary stars is the X-ray binaries, so-called because they emit X-rays. X-ray binaries are made up of a normal star and a collapsed star (a white dwarf, neutron star, or black hole). These pairs of stars produce X-rays if the stars are close enough together that material is pulled ...
Stars in Their Youth
Stars in Their Youth

... Once the hydrogen in the core is exhausted, the curtain will come down on the first act, and the subsequent acts of the stellar drama will follow. As we shall see, the subsequent acts will be of shorter and shorter duration. Astonishingly, for a drama that has gone on for tens of millions or billion ...
Beyond solar system
Beyond solar system

Document
Document

... • As I lower you toward event horizon, your perception of stars begin to change and blur. Are you getting a sinking feeling? • When you get close enough to the event horizon, no rope – no matter how strong – can stand the strain. It will snap and break, and you will begin an inexorable fall toward t ...
$doc.title

... 2a.  Mark  and  label  the  Sun  (spectral  type=G2V,  MV  =  4.83,  B-­‐V=+0.66)  and  the  star  Vega   (spectral  type:  A0V,  MV  =  0.5,  B-­‐V=0.0)  in  the  HR  diagram.  [Assume  the  tick  marks  on  the  lower   horizontal ...
1 - TeacherWeb
1 - TeacherWeb

... 14. In what part of their life cycle are most stars in the universe? ...
Black Hole
Black Hole

... It is the tiniest star, having collapsed into a superdense state. It is thought to have formed when a large star exploded as a supernova. ...
Exam Name___________________________________
Exam Name___________________________________

D2 Stellar characteristics and stellar evolution
D2 Stellar characteristics and stellar evolution

Different types of YSOs
Different types of YSOs

... Early solar system consisted of a planetary nebula-dust and gas surrounding protostar and early sun Chondrites & components clearly formed in nebula. Differentiated bodies too? ...
Open Houses at the Campus Observatory Astronomical Horizons Lecture
Open Houses at the Campus Observatory Astronomical Horizons Lecture

... • Baseballs move faster at hotter temperature • Baseballs hit walls faster & more often • Pressure is higher ...
Measuring Stars
Measuring Stars

... The double cluster in Perseus, H-R diagram shows that most young stars has not reached the MS and only most massive stars has left the MS, it is very young probably 10-15 million years ...
Stars and Star Patterns
Stars and Star Patterns

... Stars As Calendars  It seems that the constellations in the east rise a little earlier each evening. This means that the seasons are changing and we are seeing different constellations.  An example is in the Northern Hemisphere, Orion is high in the sky during the winter and Scorpio can only be s ...
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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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