- Spiral - Imperial College London
... the solar values. Thus, even if the solar activity cycle is anomalous with respect to the majority of stars (as was for example proposed by Böhm-Vitense 2007) there are stars which exhibit solar-like chromospheric and photometric variabilities. We note that the comparison of stellar and solar varia ...
... the solar values. Thus, even if the solar activity cycle is anomalous with respect to the majority of stars (as was for example proposed by Böhm-Vitense 2007) there are stars which exhibit solar-like chromospheric and photometric variabilities. We note that the comparison of stellar and solar varia ...
Volatiles in protoplanetary disks
... not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition of planets, asteroids, comets and Kuiper belt objects. Many of the chemical properties and architecture of the ...
... not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition of planets, asteroids, comets and Kuiper belt objects. Many of the chemical properties and architecture of the ...
Volatiles in protoplanetary disks
... not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition of planets, asteroids, comets and Kuiper belt objects. Many of the chemical properties and architecture of the ...
... not necessarily during the final assembly of terrestrial planets. During the lifetime of a protoplanetary disk, both solidand gas-phase chemistry is active, shaping the initial composition of planets, asteroids, comets and Kuiper belt objects. Many of the chemical properties and architecture of the ...
Elements of astronomy
... any other night. They all seem to be at the same distance from us, and to be attached to the surface of a vast hemisphere, of which the place of the observer is the centre. But, although the stars are relatively fixed, the hemisphere, Stars rise obliquely from as a whole, is in constant motion. the ...
... any other night. They all seem to be at the same distance from us, and to be attached to the surface of a vast hemisphere, of which the place of the observer is the centre. But, although the stars are relatively fixed, the hemisphere, Stars rise obliquely from as a whole, is in constant motion. the ...
The Solar System and Beyond
... inhomogeneities in the immediate environment of the Sun, required for heliospheric interface studies. During the last 50 to 100 million years, the Sun has been crossing an empty region of the galactic disk, the so-called Local Bubble, which is probably a remnant of supernova explosions. No dense clo ...
... inhomogeneities in the immediate environment of the Sun, required for heliospheric interface studies. During the last 50 to 100 million years, the Sun has been crossing an empty region of the galactic disk, the so-called Local Bubble, which is probably a remnant of supernova explosions. No dense clo ...
Tidal Effects on the Oort Cloud Comets and Dynamics of the Sun in
... The Solar System presents a complex dynamical structure and is not isolated from the Galaxy. In particular the comet reservoir of our planetary system, the Oort cloud, is extremely sensitive to the the galactic environment due to its peripheral collocation inside the Solar System. In this framework, ...
... The Solar System presents a complex dynamical structure and is not isolated from the Galaxy. In particular the comet reservoir of our planetary system, the Oort cloud, is extremely sensitive to the the galactic environment due to its peripheral collocation inside the Solar System. In this framework, ...
Digital STARLAB Teachers Guide
... projection system in its price range for portable and small fixed domes. The projector features a custom fisheye lens (patent pending) capable of depicting an accurate, high-contrast, simulated night sky with the capacity to explore a multitude of motions and displays eliminating the need for addition ...
... projection system in its price range for portable and small fixed domes. The projector features a custom fisheye lens (patent pending) capable of depicting an accurate, high-contrast, simulated night sky with the capacity to explore a multitude of motions and displays eliminating the need for addition ...
Asteroids - GEOCITIES.ws
... Asteroids that can pass inside the orbit of Mars are said to be near-Earth asteroids. The near-Earth asteroids are subdivided into several classes. The most distant--those that can cross the orbit of Mars but that have perihelion distances (q) greater than 1.3 AU--are dubbed Mars crossers. This grou ...
... Asteroids that can pass inside the orbit of Mars are said to be near-Earth asteroids. The near-Earth asteroids are subdivided into several classes. The most distant--those that can cross the orbit of Mars but that have perihelion distances (q) greater than 1.3 AU--are dubbed Mars crossers. This grou ...
Asteroids, Comets, and Meteorites: Cosmic Invaders of the Earth
... observing an apparent massive protogalaxy in its formative stages. It is 12 billion light-years from Earth, meaning the object was seen as it existed only a few billion years after the big bang. In the meantime, the Milky Way galaxy (Fig. 5), which is of fairly modest size, pulled enough matter toge ...
... observing an apparent massive protogalaxy in its formative stages. It is 12 billion light-years from Earth, meaning the object was seen as it existed only a few billion years after the big bang. In the meantime, the Milky Way galaxy (Fig. 5), which is of fairly modest size, pulled enough matter toge ...
Comet Ion Tails Purpose Introduction Materials
... from the Sun. These moving charged particles constitute the solar wind. Because the solar wind moves much faster than the speed at which the comet travels – several hundred km/s compared to tens of km/s – the ion tail will always appear straight. For both the dust and ion comet tails, their lengths ...
... from the Sun. These moving charged particles constitute the solar wind. Because the solar wind moves much faster than the speed at which the comet travels – several hundred km/s compared to tens of km/s – the ion tail will always appear straight. For both the dust and ion comet tails, their lengths ...
The Kuiper Belt Explored by Serendipitous Stellar Occultations
... decay δF = [r/(αD)]2, where D is the object-to-Earth distance (for an impact parameter smaller than αD – r). αD = R* is the radius of the star projected at the distance of the occulting object. Note that if the star’s apparent size is known, the occultation profile provides some information on the o ...
... decay δF = [r/(αD)]2, where D is the object-to-Earth distance (for an impact parameter smaller than αD – r). αD = R* is the radius of the star projected at the distance of the occulting object. Note that if the star’s apparent size is known, the occultation profile provides some information on the o ...
Astrospheres and Solar-like Stellar Winds | SpringerLink
... The solar wind does not expand forever. Eventually it runs into the local interstellar medium (LISM). The interaction region between the solar wind and LISM is the subject of Section 2.3, and it is through analogous interaction regions around other stars that solar-like stellar winds can be detected ...
... The solar wind does not expand forever. Eventually it runs into the local interstellar medium (LISM). The interaction region between the solar wind and LISM is the subject of Section 2.3, and it is through analogous interaction regions around other stars that solar-like stellar winds can be detected ...
8 Comets: Potential Sources of Prebiotic Molecules for the
... molten – otherwise they would be shaped according to the equilibrium figure of a liquid body: a sphere or, if the body rotates, an ellipsoid. What are the ices and dust mentioned in the definition of a comet made of? Cometary ices are water ice mostly, mixed with smaller quantities of other species li ...
... molten – otherwise they would be shaped according to the equilibrium figure of a liquid body: a sphere or, if the body rotates, an ellipsoid. What are the ices and dust mentioned in the definition of a comet made of? Cometary ices are water ice mostly, mixed with smaller quantities of other species li ...
Solar Superstorms and Planetary Alignments
... to gigantic lighting bolts that flash across the ring plane. When Cassini got close enough to the giant planet, mission specialists were shocked to discover lightning of immense power, up to a million times more powerful than anything on Earth. Planets and moons are not electrically inert because th ...
... to gigantic lighting bolts that flash across the ring plane. When Cassini got close enough to the giant planet, mission specialists were shocked to discover lightning of immense power, up to a million times more powerful than anything on Earth. Planets and moons are not electrically inert because th ...
Astro Review - Parkway C-2
... The first step in the sun’s formation began when a nebula started to contract. As it contracted, its temperature rose and it became a protostar. When the core of the protostar reached about 10 million K, nuclear fusion began and the sun became a star. When the forces of pressure and gravity became b ...
... The first step in the sun’s formation began when a nebula started to contract. As it contracted, its temperature rose and it became a protostar. When the core of the protostar reached about 10 million K, nuclear fusion began and the sun became a star. When the forces of pressure and gravity became b ...
Extrasolar Kuiper Belt Dust Disks
... between 5 µm and 500 µm. This thermal emission dust was observed by the IRAS and COBE space telescopes, and the interplanetary dust particles (IDPs) were detected in situ by dust detectors on the Pioneer 10 and 11, Voyager, Galileo, and Ulysses spacecrafts. Its fractional luminosity is estimated to ...
... between 5 µm and 500 µm. This thermal emission dust was observed by the IRAS and COBE space telescopes, and the interplanetary dust particles (IDPs) were detected in situ by dust detectors on the Pioneer 10 and 11, Voyager, Galileo, and Ulysses spacecrafts. Its fractional luminosity is estimated to ...
Advances in exoplanet science from Kepler (Lissauer et al. 2014)
... planets ranging from 1.26 to 1.74. For comparison, the ratio of orbital periods in the Solar System ranges from 1.63 (Venus and Earth) to 6.3 (Mars and Jupiter). The outermost planet, Kepler-11g, has a period of 118.4 days. TTVs have been used to estimate the planets’ masses. Most, if not all, have ...
... planets ranging from 1.26 to 1.74. For comparison, the ratio of orbital periods in the Solar System ranges from 1.63 (Venus and Earth) to 6.3 (Mars and Jupiter). The outermost planet, Kepler-11g, has a period of 118.4 days. TTVs have been used to estimate the planets’ masses. Most, if not all, have ...
Document
... • A spectroscopic study of coronal dimming associated with a coronal mass ejection, Harrison, R.A. and Lyons, M., 2000, Astron. Astrophys. ...
... • A spectroscopic study of coronal dimming associated with a coronal mass ejection, Harrison, R.A. and Lyons, M., 2000, Astron. Astrophys. ...
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... in the Solar System moves around the Sun on the elliptical orbit , it is positioned on the very elongated elliptical orbit though. I guess it is very well known fact that PLuto is not always the farthest from the Sun in the Solar family of objects. It takes PLuto almost 250 years to go around the Su ...
... in the Solar System moves around the Sun on the elliptical orbit , it is positioned on the very elongated elliptical orbit though. I guess it is very well known fact that PLuto is not always the farthest from the Sun in the Solar family of objects. It takes PLuto almost 250 years to go around the Su ...
Irregular Satellites of the Giant Planets
... Uranus and Neptune since these satellites have apparent motions almost exactly the same as those of their host planets (Holman et al., 2004; Kavelaars et al., 2004). In this technique several tens of images are taken of the same field over a period of a few hours. These images are then shifted at th ...
... Uranus and Neptune since these satellites have apparent motions almost exactly the same as those of their host planets (Holman et al., 2004; Kavelaars et al., 2004). In this technique several tens of images are taken of the same field over a period of a few hours. These images are then shifted at th ...
The Oort cloud as a remnant of the protosolar nebula
... by Whitworth & Summers (1985, Table 1), there is no solution of Eqs. (10) and (11) in the range of zc /zs from 1.955 to 3755. Hence, the value zc /zs = 1.955 appears to be natural as the second border of acceptability. To avoid numerical difficulties in numerical integration at the true border, we a ...
... by Whitworth & Summers (1985, Table 1), there is no solution of Eqs. (10) and (11) in the range of zc /zs from 1.955 to 3755. Hence, the value zc /zs = 1.955 appears to be natural as the second border of acceptability. To avoid numerical difficulties in numerical integration at the true border, we a ...
Measuring distances to the edge of the local group
... Two main formation models have been proposed. Wetherill (1980) proposed that planetesimals formed primarily from the agglomeration of dust within the solar nebula. Herndon (2004) showed that this model did not produce sufficiently massive planetary cores, so he proposed a model in which the cores of ...
... Two main formation models have been proposed. Wetherill (1980) proposed that planetesimals formed primarily from the agglomeration of dust within the solar nebula. Herndon (2004) showed that this model did not produce sufficiently massive planetary cores, so he proposed a model in which the cores of ...
The Origin of Comets - Wesley Grove Chapel
... very near each other, capture does not occur. This is because they seldom collide and stick together, their relative velocities almost always allow them to escape each other’s sphere of influence, their spheres of influence rarely expand, and gases are not inside these spheres to assist in capture. ...
... very near each other, capture does not occur. This is because they seldom collide and stick together, their relative velocities almost always allow them to escape each other’s sphere of influence, their spheres of influence rarely expand, and gases are not inside these spheres to assist in capture. ...
Evolution of Circumstellar Disks Around Normal Stars
... of primordial disks and is the material responsible for the formation of giant planets. Observational evidence for the dissipation of gas in primordial disks surrounding young sun–like stars is scant. Millimeter wave surveys (Dutrey et al., this volume) are on–going and confirm the basic results: 1) ...
... of primordial disks and is the material responsible for the formation of giant planets. Observational evidence for the dissipation of gas in primordial disks surrounding young sun–like stars is scant. Millimeter wave surveys (Dutrey et al., this volume) are on–going and confirm the basic results: 1) ...
Basic Solar Positional Astronomy
... Before atomic clocks, the problem with GMT was that it was based on an imaginary mean Sun. Thus it was not measurable, especially by navigators trying to calculate longitude. They require an entirely uniform, definable and measurable time scale that accords with the axis of spin of the Earth and whi ...
... Before atomic clocks, the problem with GMT was that it was based on an imaginary mean Sun. Thus it was not measurable, especially by navigators trying to calculate longitude. They require an entirely uniform, definable and measurable time scale that accords with the axis of spin of the Earth and whi ...
Solar System
The Solar System comprises the Sun and the planetary system that orbits it, either directly or indirectly. Of those objects that orbit the Sun directly, the largest eight are the planets, with the remainder being significantly smaller objects, such as dwarf planets and small Solar System bodies such as comets and asteroids. Of those that orbit the Sun indirectly, two are larger than the smallest planet.The Solar System formed 4.6 billion years ago from the gravitational collapse of a giant interstellar molecular cloud. The vast majority of the system's mass is in the Sun, with most of the remaining mass contained in Jupiter. The four smaller inner planets, Mercury, Venus, Earth and Mars, are terrestrial planets, being primarily composed of rock and metal. The four outer planets are giant planets, being substantially more massive than the terrestrials. The two largest, Jupiter and Saturn, are gas giants, being composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are ice giants, being composed largely of substances with relatively high melting points compared with hydrogen and helium, called ices, such as water, ammonia and methane. All planets have almost circular orbits that lie within a nearly flat disc called the ecliptic.The Solar System also contains smaller objects. The asteroid belt, which lies between Mars and Jupiter, mostly contains objects composed, like the terrestrial planets, of rock and metal. Beyond Neptune's orbit lie the Kuiper belt and scattered disc, populations of trans-Neptunian objects composed mostly of ices, and beyond them a newly discovered population of sednoids. Within these populations are several dozen to possibly tens of thousands of objects large enough to have been rounded by their own gravity. Such objects are categorized as dwarf planets. Identified dwarf planets include the asteroid Ceres and the trans-Neptunian objects Pluto and Eris. In addition to these two regions, various other small-body populations, including comets, centaurs and interplanetary dust, freely travel between regions. Six of the planets, at least three of the dwarf planets, and many of the smaller bodies are orbited by natural satellites, usually termed ""moons"" after the Moon. Each of the outer planets is encircled by planetary rings of dust and other small objects.The solar wind, a stream of charged particles flowing outwards from the Sun, creates a bubble-like region in the interstellar medium known as the heliosphere. The heliopause is the point at which pressure from the solar wind is equal to the opposing pressure of interstellar wind; it extends out to the edge of the scattered disc. The Oort cloud, which is believed to be the source for long-period comets, may also exist at a distance roughly a thousand times further than the heliosphere. The Solar System is located in the Orion Arm, 26,000 light-years from the center of the Milky Way.