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Properties of Stars Name
Properties of Stars Name

... Properties of Stars ...
The Sun: Our Nearest Star
The Sun: Our Nearest Star

Microsoft Power Point version
Microsoft Power Point version

... lives we observe only a brief moment in any one star’s life by studying large numbers of stars, we get a “snapshot” of one moment in the history of the stellar community we can draw conclusions just like we would with human census data…we do stellar demographics! ...
HR Diagram - TeacherWeb
HR Diagram - TeacherWeb

PHYSICS 1500 - ASTRONOMY TOTAL
PHYSICS 1500 - ASTRONOMY TOTAL

Life Cycle of a Star
Life Cycle of a Star

... Death of a star like our sun • atoms no longer fuse, fuel is used up - Outer gases escape leaving the core which collapses and shrinks - Heat still present but will continue to escape for about a billion of years ...
ASTR 1020 General Astronomy: Stars and Galaxies REVIEW
ASTR 1020 General Astronomy: Stars and Galaxies REVIEW

... No White Dwarf Can have more than 1.4M~ Otherwise it will groan and collapse under its own weight. We’ll come back to this later. ...
Deep Space Mystery Note Form 3
Deep Space Mystery Note Form 3

...  Binary stars are when there are two stars and they revolve around each other.  In these systems supernovas occur also.  Stars up to eight times the mass of our sun usually evolve into white dwarfs.  A star that is condensed to this size has a very strong gravitational pull.  With that gravity, ...
Final 2004
Final 2004

... d 40 billion years (16.) Whi h of the following is an a urate des ription of the behavior of the nu leons in the rea tion p+p ! 2 H + e+ +  ? a one neutron hanges to a proton b one proton hanges to a neutron the nu leons retain their identities d none of the above (17.) Whi h of the following ...
ultracam observations of pulsating sdB stars
ultracam observations of pulsating sdB stars

... horizontal branch stars and normal stellar evolution Post-GB and He-flash He-burning core 0.5 M H-rich envelope 0.4 M/ metal-rich - red HB 0.2 M/ metal-poor - blue HB 0. - .05 M - EHB / sdB Problems: How does RGB star lose its entire H envelope? How does it still suffer Heflash? ...
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1st Semester Earth Science Review 2014-15

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... 3. The Earth and other planets (nebular hypothesis; plate tectonics) It’s tempting to think about these topics as independent, but I want you to think about the relative scales of the systems we’ve talked about. Specifically, consider the many different objects we’ve talked about: electrons, molecul ...
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...  A star is born when temperature and pressure at its center become great enough to start nuclear fusion. ...
Stellar Physics 2
Stellar Physics 2

... B. Neutron stars are stars with a mass below the Chandrasekhar Mass limit and its electrons have become relativistic. C. Neutron stars are stars with a mass above the Chandrasekhar Mass limit, its electrons are yet to become relativistic. ...
Chapter10 (with interactive links)
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The Milky Way

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Integrative Studies 410 Our Place in the Universe

... • Conclusion: there are no stars beyond a certain distance ...
Starlight and What it Tells Us
Starlight and What it Tells Us

... – If two stars have the same color and distance, difference in brightness is due to difference in size – Dwarf and giant stars are literally dwarfs or giants ...
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DP11 Foundations of Astronomy

... The core of the Sun Just as the waves from earthquakes tell us about the Earth's interior as they travel through it, the way that waves travel through the Sun tells us about its interior. Another thing you can observe from the Sun is neutrinos. These are a type of fundamental particle produced in t ...
ppt - SLAC
ppt - SLAC

... A W-R star is “A hot (25,000 to 50,000 K), massive (more than 25 solar masses), luminous star in an advanced stage of evolution, which is losing mass in the form a powerful stellar wind. Wolf-Rayets are believed to be O stars that have lost their hydrogen envelopes, leaving their helium cores expose ...
I CAN SEE THE STARS IN YOUR EYES
I CAN SEE THE STARS IN YOUR EYES

... at this speed, the trip from Earth to the sun, a distance of 93 million miles, would take about 8 minutes, not very long for such a long trip! Yet, to get to the next closest star, Proxima Centauri, would take 4.2 years. “Hmmm…,” you think to yourself, “that might be an interesting fact to include i ...
How Bright is that star?
How Bright is that star?

... The luminosity of a star depends on two things The surface area (A) of the Star… bigger stars are brighter because there is more area to shine. And The luminosity (l ) of a square meter of surface area. L = Al ...
NCEA Level 2 Earth and Space Science (91192) 2015
NCEA Level 2 Earth and Space Science (91192) 2015

NCEA Level 2 Earth and Space Science (91192) 2015
NCEA Level 2 Earth and Space Science (91192) 2015

... Star birth explained with associated energy changes: GMC collapsing changes gravitational potential energy into heat energy. When this heat energy temperature reaches about 1 000 000 K, nuclear fusion of hydrogen into helium occurs. All stars spend a period of time on the main sequence where the sta ...
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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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