More on Cluster HR diagrams - University of Texas Astronomy
... At this point you should be able to look at Figures 19.17 (open cluster) and 19.18 (globular cluster) on p. 519 of your book, and understand clearly how we know that one was “just born” recently (about 100 million years ago), while the other must be extremely old, about 10 billion years. Can you now ...
... At this point you should be able to look at Figures 19.17 (open cluster) and 19.18 (globular cluster) on p. 519 of your book, and understand clearly how we know that one was “just born” recently (about 100 million years ago), while the other must be extremely old, about 10 billion years. Can you now ...
2010 AP Gravitation Notes
... 36. A satellite of mass m is in an elliptical orbit around the Earth, which has mass Me and radius Re. The orbit varies from closest approach of a at point A to maximum distance of b from the center of the Earth at point B. At point A, the speed of the satellite is vo Assume that the gravitational p ...
... 36. A satellite of mass m is in an elliptical orbit around the Earth, which has mass Me and radius Re. The orbit varies from closest approach of a at point A to maximum distance of b from the center of the Earth at point B. At point A, the speed of the satellite is vo Assume that the gravitational p ...
Lecture 33: The Lives of Stars Astronomy 141
... Main Sequence stars are powered by the fusion of Hydrogen into Helium in their cores The more massive a star is, the shorter its lifetime. Low-Mass stars are long-lived, spend some time as Red Giants, then leave behind a White Dwarf. Very high-mass stars have very short lives, spend a short time as ...
... Main Sequence stars are powered by the fusion of Hydrogen into Helium in their cores The more massive a star is, the shorter its lifetime. Low-Mass stars are long-lived, spend some time as Red Giants, then leave behind a White Dwarf. Very high-mass stars have very short lives, spend a short time as ...
Life_Cycle_of_a_Star_Powerpoint
... • The core shrinks and the outer parts expand • It turns red as it is cooling • This phase will last until the star exhausts its remaining fuel. • The pressure of the nuclear reaction is not strong enough to equalize the force of gravity so the star will collapse. ...
... • The core shrinks and the outer parts expand • It turns red as it is cooling • This phase will last until the star exhausts its remaining fuel. • The pressure of the nuclear reaction is not strong enough to equalize the force of gravity so the star will collapse. ...
RED GIANTS
... Helium fusion begins at the center of a giant • While the exterior layers expand, the helium core continues to contract and eventually becomes hot enough (100 million kelvins) for helium to begin to fuse into carbon and oxygen – core helium fusion – 3 He a C + energy and C + He a O + energy – occur ...
... Helium fusion begins at the center of a giant • While the exterior layers expand, the helium core continues to contract and eventually becomes hot enough (100 million kelvins) for helium to begin to fuse into carbon and oxygen – core helium fusion – 3 He a C + energy and C + He a O + energy – occur ...
Pluto Evidence
... Pluto is not a planet because it has not cleared out its local neighborhood. When a planet has cleared its local neighborhood, there are no other objects flying where it orbits. Any object that passes near the planet either gets pulled into the planet or gets flung away by the planet. Because the pl ...
... Pluto is not a planet because it has not cleared out its local neighborhood. When a planet has cleared its local neighborhood, there are no other objects flying where it orbits. Any object that passes near the planet either gets pulled into the planet or gets flung away by the planet. Because the pl ...
Galaxy1
... stars in the sky. This is because they have extremely large luminosity. They can be readily seen at great distances. • The stars in our little volume of the Galaxy are almost completely, low mass stars. • This means if we increased the volume that we are using to search for stars, we would start to ...
... stars in the sky. This is because they have extremely large luminosity. They can be readily seen at great distances. • The stars in our little volume of the Galaxy are almost completely, low mass stars. • This means if we increased the volume that we are using to search for stars, we would start to ...
PHYSICS CHAPTER 8 : Universal Gravitation
... seen every 75–76 years. Many comets with long orbital periods may appear brighter and more spectacular, but Halley is the only short-period comet that is clearly visible to the naked eye, and thus, the only naked-eye comet certain to return within a human lifetime. During its returns to the inner so ...
... seen every 75–76 years. Many comets with long orbital periods may appear brighter and more spectacular, but Halley is the only short-period comet that is clearly visible to the naked eye, and thus, the only naked-eye comet certain to return within a human lifetime. During its returns to the inner so ...
Life on Earth Came From Other Planets
... The parent star may have lost between 40% to 80% of its mass before exploding (Kalirai, et al. 2007; Liebert et al. 2005; Wachter et al. 2008) and its planets would have significantly increased their orbital distances and may have been ejected from its solar system prior to supernova. Thus the super ...
... The parent star may have lost between 40% to 80% of its mass before exploding (Kalirai, et al. 2007; Liebert et al. 2005; Wachter et al. 2008) and its planets would have significantly increased their orbital distances and may have been ejected from its solar system prior to supernova. Thus the super ...
Stellar Evolution - Hays High Indians
... Star has settled into the most stable part of its life Converts hydrogen to helium (H => He) Next step depends on the mass of the star Three different examples of stars: 1. Stars similar to our Sun 2. Stars several times more massive than the Sun 3. HUGE HUMONGOUS stars, VERY massive ...
... Star has settled into the most stable part of its life Converts hydrogen to helium (H => He) Next step depends on the mass of the star Three different examples of stars: 1. Stars similar to our Sun 2. Stars several times more massive than the Sun 3. HUGE HUMONGOUS stars, VERY massive ...
What makes a planet habitable?
... Soft X-ray and EUV induced expansion of the upper atmospheres can lead to high non-thermal loss rates present Venus, Mars ...
... Soft X-ray and EUV induced expansion of the upper atmospheres can lead to high non-thermal loss rates present Venus, Mars ...
The Stellar Cycle
... As hydrogen in the core is being used up, it starts to contract, raising temperature in the surrounding. Eventually, hydrogen will burn only in a shell. There is less gravity from above to balance this pressure. The Sun will then swell to enormous size and luminosity, and its surface temperature wil ...
... As hydrogen in the core is being used up, it starts to contract, raising temperature in the surrounding. Eventually, hydrogen will burn only in a shell. There is less gravity from above to balance this pressure. The Sun will then swell to enormous size and luminosity, and its surface temperature wil ...
Standard candles
... white dwarf star in a binary pair with a red dwarf star steals mass from the red dwarf until it is too massive to support itself against gravity any more. Then its core collapses, starting a runaway nuclear reaction and a bright explosion. Because the collapse always happens at the same mass, the lu ...
... white dwarf star in a binary pair with a red dwarf star steals mass from the red dwarf until it is too massive to support itself against gravity any more. Then its core collapses, starting a runaway nuclear reaction and a bright explosion. Because the collapse always happens at the same mass, the lu ...
Dynamics of Planetary Systems - Uppsala Astronomical Observatory
... concerned, and it may be that our planetary orbits remain stable over a time much longer than the age of the Solar System (4.6 · 109 years). However, the problem of the stability of the Solar System has remained one of the great challenges of dynamics ever since it arose during the 19th century. The ...
... concerned, and it may be that our planetary orbits remain stable over a time much longer than the age of the Solar System (4.6 · 109 years). However, the problem of the stability of the Solar System has remained one of the great challenges of dynamics ever since it arose during the 19th century. The ...
Some Important Introductory Concepts
... Kepler’s 3rd law, as modified by Newton (coming up), will be a cornerstone of much of this course, because it allows us to estimate masses of astronomical objects (e.g. masses of stars, galaxies, the existence of black holes and the mysterious “dark matter”). Example of use of Kepler’s 3rd law: Th ...
... Kepler’s 3rd law, as modified by Newton (coming up), will be a cornerstone of much of this course, because it allows us to estimate masses of astronomical objects (e.g. masses of stars, galaxies, the existence of black holes and the mysterious “dark matter”). Example of use of Kepler’s 3rd law: Th ...
Although a wall looks real, solid to sight and feel, a wall is not a wall
... Throughout most of the life of the star, the nuclear fires in its interior burn steadily, consuming hydrogen and leaving behind a residue of heavier elements. These heavier elements are the ashes of the star’s fire. Oxygen, iron, copper, and many other elements, ranging up to gold, lead, and uranium ...
... Throughout most of the life of the star, the nuclear fires in its interior burn steadily, consuming hydrogen and leaving behind a residue of heavier elements. These heavier elements are the ashes of the star’s fire. Oxygen, iron, copper, and many other elements, ranging up to gold, lead, and uranium ...
3Nov_2014
... • More distant streetlights appear dimmer than ones closer to us. • It works the same with stars! • If we know the total energy output of a star (luminosity), and we can count the number of photons we receive from that star (brightness), we can calculate its distance L d= 4pB ...
... • More distant streetlights appear dimmer than ones closer to us. • It works the same with stars! • If we know the total energy output of a star (luminosity), and we can count the number of photons we receive from that star (brightness), we can calculate its distance L d= 4pB ...
Unit 1
... • More distant streetlights appear dimmer than ones closer to us. • It works the same with stars! • If we know the total energy output of a star (luminosity), and we can count the number of photons we receive from that star (brightness), we can calculate its distance L d= 4pB ...
... • More distant streetlights appear dimmer than ones closer to us. • It works the same with stars! • If we know the total energy output of a star (luminosity), and we can count the number of photons we receive from that star (brightness), we can calculate its distance L d= 4pB ...
D1 Stellar quantities (PPT)
... ▪ The great temperature differences between the hot inner regions and the cool outer regions of the disk determined what of condensates were available for planet formation at each location from the center. The inner nebula was rich in heavy solid grains and deficient in ices and gases. The outskirts ...
... ▪ The great temperature differences between the hot inner regions and the cool outer regions of the disk determined what of condensates were available for planet formation at each location from the center. The inner nebula was rich in heavy solid grains and deficient in ices and gases. The outskirts ...
Jan 2017 - Bays Mountain Park
... propagate through the solar plasma. By looking at how the Corona’s composition changes, researchers can determine which mechanism is more important, says Tom Woods, a solar scientist at the University of Colorado at Boulder and principal investigator of MinXSS: “It’s helping address this very long-t ...
... propagate through the solar plasma. By looking at how the Corona’s composition changes, researchers can determine which mechanism is more important, says Tom Woods, a solar scientist at the University of Colorado at Boulder and principal investigator of MinXSS: “It’s helping address this very long-t ...
Atmospheric circulations of terrestrial planets orbiting low
... The primary goal of this study is to follow up on the above previous efforts to examine habitability and atmospheric circulation of M-star planets, focusing on their sensitivities to planetary rotation period. Previous modeling studies have shown that changes in rotation period can cause substantial ...
... The primary goal of this study is to follow up on the above previous efforts to examine habitability and atmospheric circulation of M-star planets, focusing on their sensitivities to planetary rotation period. Previous modeling studies have shown that changes in rotation period can cause substantial ...
Black Hole
... Review: Evolution of High-Mass Stars Stars born with more then 8 — 10 M cannot lose enough mass to become white dwarfs. These stars die by exploding as Supernovae II. Ignition of “metals” During periods when the core of a star is not hot enough so that its nuclei can produce energy by fusion, it n ...
... Review: Evolution of High-Mass Stars Stars born with more then 8 — 10 M cannot lose enough mass to become white dwarfs. These stars die by exploding as Supernovae II. Ignition of “metals” During periods when the core of a star is not hot enough so that its nuclei can produce energy by fusion, it n ...
Sections F and G
... We can image different layers of the Sun using radiation at different wavelengths since these are emitted or absorbed differently. Recall from Astrophysical Concepts, the idea of ‘optical depth’. If radiation of intensity I0 is incident on one side of a slab of material of thickness x then the emerg ...
... We can image different layers of the Sun using radiation at different wavelengths since these are emitted or absorbed differently. Recall from Astrophysical Concepts, the idea of ‘optical depth’. If radiation of intensity I0 is incident on one side of a slab of material of thickness x then the emerg ...
History of astronomy
... of Roger Bacon (1267): “Greater things than these may be performed by refracted vision. For it is is easy to understand by the canons above mentioned that the greatest things may appear exceeding small, and the contrary. For we can give such figures to transparent bodies, and dispose them in such or ...
... of Roger Bacon (1267): “Greater things than these may be performed by refracted vision. For it is is easy to understand by the canons above mentioned that the greatest things may appear exceeding small, and the contrary. For we can give such figures to transparent bodies, and dispose them in such or ...
Planetary habitability
Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and sustain life. Life may develop directly on a planet or satellite or be transferred to it from another body, a theoretical process known as panspermia. As the existence of life beyond Earth is unknown, planetary habitability is largely an extrapolation of conditions on Earth and the characteristics of the Sun and Solar System which appear favourable to life's flourishing—in particular those factors that have sustained complex, multicellular organisms and not just simpler, unicellular creatures. Research and theory in this regard is a component of planetary science and the emerging discipline of astrobiology.An absolute requirement for life is an energy source, and the notion of planetary habitability implies that many other geophysical, geochemical, and astrophysical criteria must be met before an astronomical body can support life. In its astrobiology roadmap, NASA has defined the principal habitability criteria as ""extended regions of liquid water, conditions favourable for the assembly of complex organic molecules, and energy sources to sustain metabolism.""In determining the habitability potential of a body, studies focus on its bulk composition, orbital properties, atmosphere, and potential chemical interactions. Stellar characteristics of importance include mass and luminosity, stable variability, and high metallicity. Rocky, terrestrial-type planets and moons with the potential for Earth-like chemistry are a primary focus of astrobiological research, although more speculative habitability theories occasionally examine alternative biochemistries and other types of astronomical bodies.The idea that planets beyond Earth might host life is an ancient one, though historically it was framed by philosophy as much as physical science. The late 20th century saw two breakthroughs in the field. The observation and robotic spacecraft exploration of other planets and moons within the Solar System has provided critical information on defining habitability criteria and allowed for substantial geophysical comparisons between the Earth and other bodies. The discovery of extrasolar planets, beginning in the early 1990s and accelerating thereafter, has provided further information for the study of possible extraterrestrial life. These findings confirm that the Sun is not unique among stars in hosting planets and expands the habitability research horizon beyond the Solar System.The chemistry of life may have begun shortly after the Big Bang, 13.8 billion years ago, during a habitable epoch when the Universe was only 10–17 million years old. According to the panspermia hypothesis, microscopic life—distributed by meteoroids, asteroids and other small Solar System bodies—may exist throughout the universe. Nonetheless, Earth is the only place in the universe known to harbor life. Estimates of habitable zones around other stars, along with the discovery of hundreds of extrasolar planets and new insights into the extreme habitats here on Earth, suggest that there may be many more habitable places in the universe than considered possible until very recently. On 4 November 2013, astronomers reported, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of Sun-like stars and red dwarfs within the Milky Way. 11 billion of these estimated planets may be orbiting Sun-like stars. The nearest such planet may be 12 light-years away, according to the scientists.