Our Sun, Sol - Hobbs High School
... increases the rate of hydrogen burning, expanding the outer layers. ...
... increases the rate of hydrogen burning, expanding the outer layers. ...
PHYSICS 113 Practice Questions #2
... c. whether it is loca ted on the o uter regions o r the central reg ions of the mo lecular cloud that gave it birth d. the speed and direction of its rotation e. the size of the d isk around it 15. Why do all stars spend most of their lives on the main sequence? a. because the neutrinos created insi ...
... c. whether it is loca ted on the o uter regions o r the central reg ions of the mo lecular cloud that gave it birth d. the speed and direction of its rotation e. the size of the d isk around it 15. Why do all stars spend most of their lives on the main sequence? a. because the neutrinos created insi ...
Pretest
... like a thick ribbon of stars across the night sky. This is because we are looking at it from within one of its arms, so it is like looking at the edge of a dinner plate. From above and below, the Milky Way would look like a disc or a spiral because you would be outside of it and able to see the enti ...
... like a thick ribbon of stars across the night sky. This is because we are looking at it from within one of its arms, so it is like looking at the edge of a dinner plate. From above and below, the Milky Way would look like a disc or a spiral because you would be outside of it and able to see the enti ...
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2-2 wkst - Home [www.petoskeyschools.org]
... b. As stars get older, they lose some of their material. c. Stars last forever. d. New stars form from the material of old stars. 2. During a star’s life cycle, hydrogen changes to helium in a process called ____________________. 3.When a star dies, either gradually or in a big explosion, much of it ...
... b. As stars get older, they lose some of their material. c. Stars last forever. d. New stars form from the material of old stars. 2. During a star’s life cycle, hydrogen changes to helium in a process called ____________________. 3.When a star dies, either gradually or in a big explosion, much of it ...
Chapter 10 Measuring the Stars: Giants, Dwarfs, and the Main
... * Some stars are supergiants and are also located near the top right (_______________) * White dwarfs are hot, faint, small stars near the bottom of the diagram • Some white dwarfs are Earth sized * Bright and near stars plotted on diagram Extending the Cosmic Distance Scale * Spectroscopic Parallax ...
... * Some stars are supergiants and are also located near the top right (_______________) * White dwarfs are hot, faint, small stars near the bottom of the diagram • Some white dwarfs are Earth sized * Bright and near stars plotted on diagram Extending the Cosmic Distance Scale * Spectroscopic Parallax ...
Astro 10 Practice Test 3
... b. The helium in their cores has all been used up, which means they’ve started buring hydrogen for the first time. c. They have been ejected from the cluster by gravitational encounters with other stars. d. They’ve run out of hydrogen to burn in their cores, and have evolved into red giants. ...
... b. The helium in their cores has all been used up, which means they’ve started buring hydrogen for the first time. c. They have been ejected from the cluster by gravitational encounters with other stars. d. They’ve run out of hydrogen to burn in their cores, and have evolved into red giants. ...
MASS – LUMINOSITY RELATION FOR MASSIVE STARS
... Near the stellar surface we have Mr ≈ M and Lr ≈ L, and adopting κ ≈ κe = const, we may integrate equation (s2.3) to obtain ...
... Near the stellar surface we have Mr ≈ M and Lr ≈ L, and adopting κ ≈ κe = const, we may integrate equation (s2.3) to obtain ...
Document
... • Four hydrogen atoms are fused to produce one helium atom. The remaining matter is given off in the form of heat and light energy. ...
... • Four hydrogen atoms are fused to produce one helium atom. The remaining matter is given off in the form of heat and light energy. ...
HW #8 Stellar Evolution I Solutions
... luminosity, radius and temperature while on the main sequence, because of the natural thermostat mechanism in main sequence stars. The thermostat mechanism acts to return the core fusion rates back to an equilibrium rate in the event of fluctuations in the core fusion rate. This is known as a negati ...
... luminosity, radius and temperature while on the main sequence, because of the natural thermostat mechanism in main sequence stars. The thermostat mechanism acts to return the core fusion rates back to an equilibrium rate in the event of fluctuations in the core fusion rate. This is known as a negati ...
Comet Pan-Starrs 12 March 2013
... Fe disintegrates into protons and neutrons Protons and electrons combine to form neutrons This takes heat out of the star Without pressure support the core collapses Gravitational potential energy is converted to heat, and the outer part of the star is ejected • The core may stabilize as a neutron ...
... Fe disintegrates into protons and neutrons Protons and electrons combine to form neutrons This takes heat out of the star Without pressure support the core collapses Gravitational potential energy is converted to heat, and the outer part of the star is ejected • The core may stabilize as a neutron ...
Big Bang and Life Cycle of Stars
... • According to this theory, all the matter and energy of the universe were at one time concentrated in an incredibly hot dense region, a form of matter called plasma. • At a super heated state, it was too hot for atoms to form, or other properties such as gravity or electromagnetic forces to occur • ...
... • According to this theory, all the matter and energy of the universe were at one time concentrated in an incredibly hot dense region, a form of matter called plasma. • At a super heated state, it was too hot for atoms to form, or other properties such as gravity or electromagnetic forces to occur • ...
Chap. 02
... – no further helium burning, produce helium white dwarf Star M > 1.5 Msun – core not degenerate (ρ < 106 g cm-3) – but high temperature (> 108 K), ignite helium burning – Peaceful transition to helium burning Star 0.4 Msun < M < 1.5 Msun – core degenerate (ρ < 106 g cm-3) – and high temperature (> 1 ...
... – no further helium burning, produce helium white dwarf Star M > 1.5 Msun – core not degenerate (ρ < 106 g cm-3) – but high temperature (> 108 K), ignite helium burning – Peaceful transition to helium burning Star 0.4 Msun < M < 1.5 Msun – core degenerate (ρ < 106 g cm-3) – and high temperature (> 1 ...
TYPES OF STARS
... Modified from: http://cas.sdss.org/dr5/en/proj/teachers/basic/spectraltypes/lesson.asp When astronomers look through their telescopes, they see billions of stars. How do they make sense of all these stars? The goal of this problem set is for you to understand that astronomers classify stars on the b ...
... Modified from: http://cas.sdss.org/dr5/en/proj/teachers/basic/spectraltypes/lesson.asp When astronomers look through their telescopes, they see billions of stars. How do they make sense of all these stars? The goal of this problem set is for you to understand that astronomers classify stars on the b ...
1) The following questions refer to the HR diagram
... D) they are the end-products of small, low-mass stars. E) they are the opposite of black holes. 22) What happens to the surface temperature and luminosity when a protostar radiatively contracts? A) Its surface temperature remains the same and its luminosity decreases. B) Its surface temperature and ...
... D) they are the end-products of small, low-mass stars. E) they are the opposite of black holes. 22) What happens to the surface temperature and luminosity when a protostar radiatively contracts? A) Its surface temperature remains the same and its luminosity decreases. B) Its surface temperature and ...
Part 1
... (d) Draw the evolutionary track of the proto-Sun, starting from the parent gas cloud where the Sun was born. ...
... (d) Draw the evolutionary track of the proto-Sun, starting from the parent gas cloud where the Sun was born. ...
Stellar Evolution
... • When hydrogen fusion starts at the end of the protostar stage, a star is born on the `zero-age main sequence’. • As hydrogen is being converted into helium in the core of a star, its structure changes slowly and stellar evolution begins. ...
... • When hydrogen fusion starts at the end of the protostar stage, a star is born on the `zero-age main sequence’. • As hydrogen is being converted into helium in the core of a star, its structure changes slowly and stellar evolution begins. ...
2 - Lnk2Lrn
... Stars Stars are formed by interstellar dust coming together through mutual gravitational attraction. The loss of potential energy is responsible for the initial high temperature necessary for fusion. The fusion process releases so much energy that the pressure created prevents the star from c ...
... Stars Stars are formed by interstellar dust coming together through mutual gravitational attraction. The loss of potential energy is responsible for the initial high temperature necessary for fusion. The fusion process releases so much energy that the pressure created prevents the star from c ...
Star
A star is a luminous sphere of plasma held together by its own gravity. The nearest star to Earth is the Sun. Other stars are visible from Earth during the night, appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth. Historically, the most prominent stars were grouped into constellations and asterisms, and the brightest stars gained proper names. Extensive catalogues of stars have been assembled by astronomers, which provide standardized star designations.For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space. Once the hydrogen in the core of a star is nearly exhausted, almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the star's lifetime and, for some stars, by supernova nucleosynthesis when it explodes. Near the end of its life, a star can also contain degenerate matter. Astronomers can determine the mass, age, metallicity (chemical composition), and many other properties of a star by observing its motion through space, luminosity, and spectrum respectively. The total mass of a star is the principal determinant of its evolution and eventual fate. Other characteristics of a star, including diameter and temperature, change over its life, while the star's environment affects its rotation and movement. A plot of the temperature of many stars against their luminosities, known as a Hertzsprung–Russell diagram (H–R diagram), allows the age and evolutionary state of a star to be determined.A star's life begins with the gravitational collapse of a gaseous nebula of material composed primarily of hydrogen, along with helium and trace amounts of heavier elements. Once the stellar core is sufficiently dense, hydrogen becomes steadily converted into helium through nuclear fusion, releasing energy in the process. The remainder of the star's interior carries energy away from the core through a combination of radiative and convective processes. The star's internal pressure prevents it from collapsing further under its own gravity. Once the hydrogen fuel at the core is exhausted, a star with at least 0.4 times the mass of the Sun expands to become a red giant, in some cases fusing heavier elements at the core or in shells around the core. The star then evolves into a degenerate form, recycling a portion of its matter into the interstellar environment, where it will contribute to the formation of a new generation of stars with a higher proportion of heavy elements. Meanwhile, the core becomes a stellar remnant: a white dwarf, a neutron star, or (if it is sufficiently massive) a black hole.Binary and multi-star systems consist of two or more stars that are gravitationally bound, and generally move around each other in stable orbits. When two such stars have a relatively close orbit, their gravitational interaction can have a significant impact on their evolution. Stars can form part of a much larger gravitationally bound structure, such as a star cluster or a galaxy.