Glencoe Earth Science
... Most of the heat energy produced by the Sun is caused by the fission, or radioactive decay, of helium into hydrogen in the Sun’s core. ...
... Most of the heat energy produced by the Sun is caused by the fission, or radioactive decay, of helium into hydrogen in the Sun’s core. ...
Solar System
... planets,[lower-alpha 3] with the remainder being significantly Oort cloud, which is thought to be the source for longsmaller objects, such as dwarf planets and small Solar period comets, may also exist at a distance roughly a thouSystem bodies. Of the objects that orbit the Sun indi- sand times furth ...
... planets,[lower-alpha 3] with the remainder being significantly Oort cloud, which is thought to be the source for longsmaller objects, such as dwarf planets and small Solar period comets, may also exist at a distance roughly a thouSystem bodies. Of the objects that orbit the Sun indi- sand times furth ...
Planet formation around stars of various masses: The snow line and
... with σ = σMMSN M⋆ /M⊙ for several different stellar masses over time for irradiation only, and for accretion + irradiation. We locate the snow line where Tmid = 170 K. More detailed derivations of this temperature (e.g. Podolak & Zucker 2004; Lecar et al. 2006) do not change the snow line distance s ...
... with σ = σMMSN M⋆ /M⊙ for several different stellar masses over time for irradiation only, and for accretion + irradiation. We locate the snow line where Tmid = 170 K. More detailed derivations of this temperature (e.g. Podolak & Zucker 2004; Lecar et al. 2006) do not change the snow line distance s ...
PDF Full-text
... Abstract: Exoplanets are born and evolve in the radiation and particle environment created by their host star. The host star’s optical and infrared radiation heats the exoplanet’s lower atmosphere and surface, while the ultraviolet, extreme ultraviolet and X-radiation control the photochemistry and ...
... Abstract: Exoplanets are born and evolve in the radiation and particle environment created by their host star. The host star’s optical and infrared radiation heats the exoplanet’s lower atmosphere and surface, while the ultraviolet, extreme ultraviolet and X-radiation control the photochemistry and ...
Document
... So, whatever calendar one adopts should account for the Tropical year and not the Sidereal or otherwise, the seasons will start earlier by about 20 minutes each year. The value of a Mean Tropical Year = 365.256363004 - .014172604493 = 365.2421904 days. The tropical year actually changes over the cen ...
... So, whatever calendar one adopts should account for the Tropical year and not the Sidereal or otherwise, the seasons will start earlier by about 20 minutes each year. The value of a Mean Tropical Year = 365.256363004 - .014172604493 = 365.2421904 days. The tropical year actually changes over the cen ...
Sample pages 1 PDF
... interest of Mercury’s passages across the Sun’s face has not inspired scientific expeditions to distant lands where bones of extinct birds might be found. These Mercurian events lack the romance of the Venus transits! Nevertheless, odd things have been reported from time to time. In fact (undoubtedl ...
... interest of Mercury’s passages across the Sun’s face has not inspired scientific expeditions to distant lands where bones of extinct birds might be found. These Mercurian events lack the romance of the Venus transits! Nevertheless, odd things have been reported from time to time. In fact (undoubtedl ...
White dwarf cooling sequences and cosmochronology
... lighter liquid left behind is redistributed by Rayleigh-Taylor instabilities [22, 23, 29, 31]. The result is an enrichment of oxygen in the central layers and its depletion in the outer ones. Even when rotation is considered, convection is indeed an efficient mechanism to redistribute the carbon ric ...
... lighter liquid left behind is redistributed by Rayleigh-Taylor instabilities [22, 23, 29, 31]. The result is an enrichment of oxygen in the central layers and its depletion in the outer ones. Even when rotation is considered, convection is indeed an efficient mechanism to redistribute the carbon ric ...
P1 topic 3 - WordPress.com
... Two major theories about the origin of the Universe are the Big Bang and the Steady State theories. Some evidence supports both theories. Other evidence supports only one theory. By considering the evidence, discuss why one of these theories is preferred by most scientists. ...
... Two major theories about the origin of the Universe are the Big Bang and the Steady State theories. Some evidence supports both theories. Other evidence supports only one theory. By considering the evidence, discuss why one of these theories is preferred by most scientists. ...
black hole
... The core of helium ash cannot generate nuclear energy. Nevertheless, it can grow hotter—because it contracts and converts gravitational energy into thermal energy. The rising temperature heats the unprocessed hydrogen just outside the core—hydrogen that was never previously hot enough to fuse. ...
... The core of helium ash cannot generate nuclear energy. Nevertheless, it can grow hotter—because it contracts and converts gravitational energy into thermal energy. The rising temperature heats the unprocessed hydrogen just outside the core—hydrogen that was never previously hot enough to fuse. ...
Sidereal Time Distribution in Large-Scale of Orbits
... In astronomy, we are concerned with how long it takes the Earth to spin with respect to the “fixed” stars, not the Sun. So, we would like a timescale that removes the complication of Earth's orbit around the Sun, and just focuses on how long it takes the Earth to spin 360 degrees with respect to the ...
... In astronomy, we are concerned with how long it takes the Earth to spin with respect to the “fixed” stars, not the Sun. So, we would like a timescale that removes the complication of Earth's orbit around the Sun, and just focuses on how long it takes the Earth to spin 360 degrees with respect to the ...
EARTH SCIENCE, PAGE I. Introduction Earth Science
... a. Physical Geology - study of the Earth's materials, such as minerals and rocks, and the various physical and chemical changes that occur on its surface and in its interior b. Historical Geology - history of the planet and its life forms from its origin to the present 2. Oceanography - study of the ...
... a. Physical Geology - study of the Earth's materials, such as minerals and rocks, and the various physical and chemical changes that occur on its surface and in its interior b. Historical Geology - history of the planet and its life forms from its origin to the present 2. Oceanography - study of the ...
Reflection #12: The Journey Ends
... exploration, people have developed many tools and products that have become very important in enriching our lives. Humans have traveled to the moon, landed probes on Mars and Venus, and sent probes speeding past Jupiter, Saturn and Uranus. More recently we have built an International Space Station, ...
... exploration, people have developed many tools and products that have become very important in enriching our lives. Humans have traveled to the moon, landed probes on Mars and Venus, and sent probes speeding past Jupiter, Saturn and Uranus. More recently we have built an International Space Station, ...
White Dwarf Stars - Stellar Physics Department
... H for magnetic white dwarfs that do show any detectable polarization. P for polarized magnetic white dwarfs. V for variable white dwarfs. And finally to complete the classification, a temperature index can follow their spectral classification. This index is defined as θ = 50400/Teff . Therefore, a w ...
... H for magnetic white dwarfs that do show any detectable polarization. P for polarized magnetic white dwarfs. V for variable white dwarfs. And finally to complete the classification, a temperature index can follow their spectral classification. This index is defined as θ = 50400/Teff . Therefore, a w ...
Stars
... • Luminosity is measured in units of energy emitted per second, or watts. The Sun’s luminosity is about 3.85 × 1026 W. The values for other stars vary widely, from about 0.0001 to more than 1 million times the Sun’s luminosity. No other stellar property varies as much. ...
... • Luminosity is measured in units of energy emitted per second, or watts. The Sun’s luminosity is about 3.85 × 1026 W. The values for other stars vary widely, from about 0.0001 to more than 1 million times the Sun’s luminosity. No other stellar property varies as much. ...
Arguments for the presence of a distant large
... necessarily be subjective, as there is no way of distinguishing such comets. The scenario that the alignment is due to a recent single approach of a perturber on a hyperbolic orbit, such as a passing star, is not possible, because the cluster in Fig. 2 extends to nearly 2708. If we reject comet 1993 ...
... necessarily be subjective, as there is no way of distinguishing such comets. The scenario that the alignment is due to a recent single approach of a perturber on a hyperbolic orbit, such as a passing star, is not possible, because the cluster in Fig. 2 extends to nearly 2708. If we reject comet 1993 ...
Arguments for the presence of a distant large undiscovered Solar
... necessarily be subjective, as there is no way of distinguishing such comets. The scenario that the alignment is due to a recent single approach of a perturber on a hyperbolic orbit, such as a passing star, is not possible, because the cluster in Fig. 2 extends to nearly 2708. If we reject comet 1993 ...
... necessarily be subjective, as there is no way of distinguishing such comets. The scenario that the alignment is due to a recent single approach of a perturber on a hyperbolic orbit, such as a passing star, is not possible, because the cluster in Fig. 2 extends to nearly 2708. If we reject comet 1993 ...
Arguments for the presence of a distant large undiscovered Solar
... necessarily be subjective, as there is no way of distinguishing such comets. The scenario that the alignment is due to a recent single approach of a perturber on a hyperbolic orbit, such as a passing star, is not possible, because the cluster in Fig. 2 extends to nearly 2708. If we reject comet 1993 ...
... necessarily be subjective, as there is no way of distinguishing such comets. The scenario that the alignment is due to a recent single approach of a perturber on a hyperbolic orbit, such as a passing star, is not possible, because the cluster in Fig. 2 extends to nearly 2708. If we reject comet 1993 ...
Debris disks: dynamics of small particles in
... Hot and cold dust around old F star The 1Gyr old F2V star η Corvi is most notable for its resolved Kuiper Belt, which SCUBA imaging at 450μm shows is near edge-on with a radius of ~100AU and central cavity (Wyatt et al. 2005) The SED shows presence of hot dust, which mid-IR imaging confirms placing ...
... Hot and cold dust around old F star The 1Gyr old F2V star η Corvi is most notable for its resolved Kuiper Belt, which SCUBA imaging at 450μm shows is near edge-on with a radius of ~100AU and central cavity (Wyatt et al. 2005) The SED shows presence of hot dust, which mid-IR imaging confirms placing ...
The Solar System
... – Outermost region = reddish brown to black (organic composition) – Innermost region = gray (carbon); light gray = stony/metallic Used with permission of V.Morris, Phillips Preparatory School ...
... – Outermost region = reddish brown to black (organic composition) – Innermost region = gray (carbon); light gray = stony/metallic Used with permission of V.Morris, Phillips Preparatory School ...
Homework #3, AST 203, Spring 2010
... solar system, including Jupiter, Saturn, Uranus and Neptune (many have argued that Uranus and Neptune should be in their own category of “ice giants”; they are actually mostly frozen gas, not vaporous gas like Jupiter and Saturn” • “Dwarf Planets”, some found in the main asteroid belt between Mars a ...
... solar system, including Jupiter, Saturn, Uranus and Neptune (many have argued that Uranus and Neptune should be in their own category of “ice giants”; they are actually mostly frozen gas, not vaporous gas like Jupiter and Saturn” • “Dwarf Planets”, some found in the main asteroid belt between Mars a ...
Chapter 2 | The Vastness of Space
... as his audience, was aware of the basics of naked-eye astronomy. For example, they knew correctly that the Moon shines by reflected light from the Sun. One must understand the essence and logical basis of ancient and medieval Earthcentered astronomy to understand the arguments that led to its demise ...
... as his audience, was aware of the basics of naked-eye astronomy. For example, they knew correctly that the Moon shines by reflected light from the Sun. One must understand the essence and logical basis of ancient and medieval Earthcentered astronomy to understand the arguments that led to its demise ...
Constraints on a Chance Universe & The Anthropic Principle
... fp - the fraction of stars that have planets similar to Earth Based on the most recent successes in finding extrasolar planets orbiting distant stars, it would seem that the value of the first ½ of this factor would be rather high. Optimists placing its value at 1.0 and pessimists at 0.1 (about 10% ...
... fp - the fraction of stars that have planets similar to Earth Based on the most recent successes in finding extrasolar planets orbiting distant stars, it would seem that the value of the first ½ of this factor would be rather high. Optimists placing its value at 1.0 and pessimists at 0.1 (about 10% ...
Three newly discovered sub-Jupiter-mass planets: WASP
... The WASP data were processed and searched for transit signals as described in Collier Cameron et al. (2006), and the candidate selection process was performed as described in Collier Cameron et al. (2007). We perform a search for transits on each season of data from each camera separately and we per ...
... The WASP data were processed and searched for transit signals as described in Collier Cameron et al. (2006), and the candidate selection process was performed as described in Collier Cameron et al. (2007). We perform a search for transits on each season of data from each camera separately and we per ...
fifth midterm -- review problems
... A 1.00 kg air cart similar to the one used in class is moving horizontally at a velocity of 0.256 m/s to the left. The cart hits a second 0.500 kg cart moving at a speed of 0.128 m/s in the same direction. If the two carts stick together, find the final velocity (speed and direction). Find the inter ...
... A 1.00 kg air cart similar to the one used in class is moving horizontally at a velocity of 0.256 m/s to the left. The cart hits a second 0.500 kg cart moving at a speed of 0.128 m/s in the same direction. If the two carts stick together, find the final velocity (speed and direction). Find the inter ...
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.