1 Stars
... For most of a star’s life, hydrogen atoms fuse to form helium atoms. A star like this is a main sequence star. The hotter a main sequence star is, the brighter it is. A star remains on the main sequence as long as it is fusing hydrogen to form helium. Our Sun has been a main sequence star for about ...
... For most of a star’s life, hydrogen atoms fuse to form helium atoms. A star like this is a main sequence star. The hotter a main sequence star is, the brighter it is. A star remains on the main sequence as long as it is fusing hydrogen to form helium. Our Sun has been a main sequence star for about ...
Document
... stable part of their life cycle. White dwarfs are hot and dim and cannot be seen without a telescope. Red giants are cool and bright and some can be seen without a telescope. Can you locate blue giants on the H-R diagram? ...
... stable part of their life cycle. White dwarfs are hot and dim and cannot be seen without a telescope. Red giants are cool and bright and some can be seen without a telescope. Can you locate blue giants on the H-R diagram? ...
Lecture Eight (Powerpoint format) - Flash
... Binary stars are significant because they allow the masses, periods, and separations of each star to be accurately ...
... Binary stars are significant because they allow the masses, periods, and separations of each star to be accurately ...
H R Diagram Online Activity
... “Hertzsprung-Russell Diagram” page: * Read the first paragraph to find this answer: 1. What is a Hertzsprung-Russell Diagram? ___________________________________________________ * Look at the paragraphs below the pic of a HR Diagram… Find and complete these sentences: 2. “The position of each dot on ...
... “Hertzsprung-Russell Diagram” page: * Read the first paragraph to find this answer: 1. What is a Hertzsprung-Russell Diagram? ___________________________________________________ * Look at the paragraphs below the pic of a HR Diagram… Find and complete these sentences: 2. “The position of each dot on ...
pkt 14 Astrophysics
... Constellations - A group of stars in a recognizable pattern that appear to be near each other in space. Nebula is an interstellar cloud of dust, hydrogen gas and plasma. It is the first stage of a star's cycle but it can also refer to the remains of a dying star (planetary nebula). Originally nebula ...
... Constellations - A group of stars in a recognizable pattern that appear to be near each other in space. Nebula is an interstellar cloud of dust, hydrogen gas and plasma. It is the first stage of a star's cycle but it can also refer to the remains of a dying star (planetary nebula). Originally nebula ...
Chemical Universe. - University of Texas Astronomy
... the star produces neon; at two billion degrees Celsius (3.6 billion F), oxygen. The energy released in these nuclear reactions is what powers the stars. “That’s what the star’s structure cares about,” Sneden says. “The star’s structure could care less that it’s changing hydrogen into helium, helium ...
... the star produces neon; at two billion degrees Celsius (3.6 billion F), oxygen. The energy released in these nuclear reactions is what powers the stars. “That’s what the star’s structure cares about,” Sneden says. “The star’s structure could care less that it’s changing hydrogen into helium, helium ...
Triangulation Trigonometric Parallax
... – Superimposed on this orbital motion are small random motions of about 20 km/sec – In addition to their motion through space, stars spin on their axes and this spin can be measured using the Doppler shift technique – young stars are found to rotate faster than old stars ...
... – Superimposed on this orbital motion are small random motions of about 20 km/sec – In addition to their motion through space, stars spin on their axes and this spin can be measured using the Doppler shift technique – young stars are found to rotate faster than old stars ...
9 Measuring the properties of stars - Journigan-wiki
... It offers a simple, pictorial summary of stellar properties. Most stars lie on the main sequence with the hotter stars being more luminous. Blue stars are hottest while red stars are the coolest A star’s mass determines its location along the main sequence with more massive stars located at the top. ...
... It offers a simple, pictorial summary of stellar properties. Most stars lie on the main sequence with the hotter stars being more luminous. Blue stars are hottest while red stars are the coolest A star’s mass determines its location along the main sequence with more massive stars located at the top. ...
Red Giants - Faculty Web Pages
... good measure. Today we'll be focusing on those few Type-M stars that are amongst the brightest stars in the sky. Why are these stars so bright? What is going on with them? These unusually bright red stars are called “Red Giants.” Giant stars, and especially Red Giants, are stars that are near the en ...
... good measure. Today we'll be focusing on those few Type-M stars that are amongst the brightest stars in the sky. Why are these stars so bright? What is going on with them? These unusually bright red stars are called “Red Giants.” Giant stars, and especially Red Giants, are stars that are near the en ...
www.aavso.org
... Cepheids are a type of variable stars that fluctuate in brightness. There is a well defined relationship between brightness and the Period of the brightness variation. Cepheids were used to determine the distance to the Andromeda Galaxy and proved that the universe was much larger than just the Mil ...
... Cepheids are a type of variable stars that fluctuate in brightness. There is a well defined relationship between brightness and the Period of the brightness variation. Cepheids were used to determine the distance to the Andromeda Galaxy and proved that the universe was much larger than just the Mil ...
Challenging our Understanding of Stellar Structure and Evolution
... Why? First, the ’tops’ of both stellar maps contain relatively rare objects, for which large populations are not found until the observing horizon reaches hundreds or thousands of parsecs. Second, the ’bottoms’ and ’sides’ of both maps contain stars, either intrinsically faint, or whose rarity guara ...
... Why? First, the ’tops’ of both stellar maps contain relatively rare objects, for which large populations are not found until the observing horizon reaches hundreds or thousands of parsecs. Second, the ’bottoms’ and ’sides’ of both maps contain stars, either intrinsically faint, or whose rarity guara ...
Ch13_Lecture - Chemistry at Winthrop University
... – Superimposed on this orbital motion are small random motions of about 20 km/sec – In addition to their motion through space, stars spin on their axes and this spin can be measured using the Doppler shift technique – young stars are found to rotate faster than old stars ...
... – Superimposed on this orbital motion are small random motions of about 20 km/sec – In addition to their motion through space, stars spin on their axes and this spin can be measured using the Doppler shift technique – young stars are found to rotate faster than old stars ...
DTU 8e Chap 11 Characterizing Stars
... The modern classification scheme for stars, based on their spectra, was developed at the Harvard College Observatory in the late nineteenth century. Female astronomers, initially led by Edward C. Pickering and Williamina Fleming, and then by Annie Jump Cannon, analyzed hundreds of thousands of spect ...
... The modern classification scheme for stars, based on their spectra, was developed at the Harvard College Observatory in the late nineteenth century. Female astronomers, initially led by Edward C. Pickering and Williamina Fleming, and then by Annie Jump Cannon, analyzed hundreds of thousands of spect ...
life cycles of stars
... In which order will a single star of one solar mass progress through the various stages of stellar evolution? 1. Planetary nebula, main-sequence star, white dwarf, black hole 2. Proto-star, main-sequence star, planetary nebula, white dwarf 3. Proto-star, red giant, supernova, planetary nebula 4. Pr ...
... In which order will a single star of one solar mass progress through the various stages of stellar evolution? 1. Planetary nebula, main-sequence star, white dwarf, black hole 2. Proto-star, main-sequence star, planetary nebula, white dwarf 3. Proto-star, red giant, supernova, planetary nebula 4. Pr ...
Evolution of our Sun
... Explain why a massive star only lives a short time? What elements are created in a sun-like star? What elements are created in a massive star? Evolution of the Sun – Part 2 Name and briefly describe the stages that our sun will go through as it ages. About how long does our sun live as a main sequen ...
... Explain why a massive star only lives a short time? What elements are created in a sun-like star? What elements are created in a massive star? Evolution of the Sun – Part 2 Name and briefly describe the stages that our sun will go through as it ages. About how long does our sun live as a main sequen ...
Shining Light on the Stars: The Hertzsprung-Russell
... Our Sun is located here on the diagram, and as before, the 122 brightest stars visible in the night sky from Earth are located here. But what about all the stars in the nearby solar neighborhood, most of which are too faint to be seen without a telescope? We immediately see that these two groups of ...
... Our Sun is located here on the diagram, and as before, the 122 brightest stars visible in the night sky from Earth are located here. But what about all the stars in the nearby solar neighborhood, most of which are too faint to be seen without a telescope? We immediately see that these two groups of ...
the stars - Uni Heidelberg
... completely into helium. The star now burns helium in the nucleus and hydrogen in a shell surrounding it. The star starts to expand and becomes a red giant. Giant stars are very big and relatively cool, they radiate a large amount of energy and appear very luminous. When the star finishes all kinds o ...
... completely into helium. The star now burns helium in the nucleus and hydrogen in a shell surrounding it. The star starts to expand and becomes a red giant. Giant stars are very big and relatively cool, they radiate a large amount of energy and appear very luminous. When the star finishes all kinds o ...
THE STARS G. Iafrate(a), M. Ramella(a) and V. Bologna(b) (a) INAF
... completely into helium. The star now burns helium in the nucleus and hydrogen in a shell surrounding it. The star starts to expand and becomes a red giant. Giant stars are very big and relatively cool, they radiate a large amount of energy and appear very luminous. When the star finishes all kinds o ...
... completely into helium. The star now burns helium in the nucleus and hydrogen in a shell surrounding it. The star starts to expand and becomes a red giant. Giant stars are very big and relatively cool, they radiate a large amount of energy and appear very luminous. When the star finishes all kinds o ...
Iron does not burn.
... atom can wait on average a few million years before it undergoes this transition. The two levels of the hydrogen 1s ground state, slightly split by the interaction between the electron spin and the nuclear spin. The splitting is known as hyperfine structure. Even though this is a RARE transition, th ...
... atom can wait on average a few million years before it undergoes this transition. The two levels of the hydrogen 1s ground state, slightly split by the interaction between the electron spin and the nuclear spin. The splitting is known as hyperfine structure. Even though this is a RARE transition, th ...
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.