Cycles of magnetic activity in solar-type stars. The place of the Sun
... these 50 stars with cycles they have found only 12 stars and the Sun to be characterized by the cyclic activity of the "Excellent" class. We illustrate the method of cyclic period calculation with Scargle’s periodogram technique on the example of the Sun. We obtained the periodogram of the yearly av ...
... these 50 stars with cycles they have found only 12 stars and the Sun to be characterized by the cyclic activity of the "Excellent" class. We illustrate the method of cyclic period calculation with Scargle’s periodogram technique on the example of the Sun. We obtained the periodogram of the yearly av ...
PDF only - at www.arxiv.org.
... regimes capture dust emission because of the relatively low grain temperature, 20-60 K. Such emission is important within our Solar System, in proto-planetary disks where we believe planetary systems like our own are forming, and throughout the disk of the Mil ...
... regimes capture dust emission because of the relatively low grain temperature, 20-60 K. Such emission is important within our Solar System, in proto-planetary disks where we believe planetary systems like our own are forming, and throughout the disk of the Mil ...
Particle-Gas Dynamics and Primary Accretion
... density σg(R) (g cm–2), at distance R from the star, are based on assumptions about emission from solid particles, and will underestimate the disk mass once particles have grown past millimeter size. The concept of the minimum mass nebula (MMN) (e.g., Hayashi, 1981; Hayashi et al., 1985) is a handy ...
... density σg(R) (g cm–2), at distance R from the star, are based on assumptions about emission from solid particles, and will underestimate the disk mass once particles have grown past millimeter size. The concept of the minimum mass nebula (MMN) (e.g., Hayashi, 1981; Hayashi et al., 1985) is a handy ...
mean field magnetohydrodynamics of accretion disks
... steep vertical stratification in z combined with full radial dependences in $ and axisymmetric motions in the tangential direction ’) to 1.5D (integration over z) requires that we explicitly treat the vacuum fields above and below the disk all the way out to infinity, which is a crucial missing ingr ...
... steep vertical stratification in z combined with full radial dependences in $ and axisymmetric motions in the tangential direction ’) to 1.5D (integration over z) requires that we explicitly treat the vacuum fields above and below the disk all the way out to infinity, which is a crucial missing ingr ...
Irregular Satellites of the Planets: Products of Capture in the Early
... Here, a p is the orbital semimajor axis of the planet and µ = m p /M" , where m p and M" are the masses of the planet and Sun, respectively. Values of r H for the giant planets are from ∼0.35 AU to 0.77 AU, increasing with distance from the Sun (Table 1). Most regular satellites follow orbits of low ...
... Here, a p is the orbital semimajor axis of the planet and µ = m p /M" , where m p and M" are the masses of the planet and Sun, respectively. Values of r H for the giant planets are from ∼0.35 AU to 0.77 AU, increasing with distance from the Sun (Table 1). Most regular satellites follow orbits of low ...
4373 - Zuber, M. T., H. Y. McSween Jr., R. P. Binzel, L. T. Elkins
... to be consistent with chondrites, but could not constrain the metal content. The composition of the silicate portion (mantle + crust) of Vesta was estimated (Jones 1984) based on mineral-melt partitioning of Mg, Si, and Sc. This bulk silicate composition was equivalent to 75% olivine plus 25% eucrit ...
... to be consistent with chondrites, but could not constrain the metal content. The composition of the silicate portion (mantle + crust) of Vesta was estimated (Jones 1984) based on mineral-melt partitioning of Mg, Si, and Sc. This bulk silicate composition was equivalent to 75% olivine plus 25% eucrit ...
mission design - Messenger - The Johns Hopkins University Applied
... Mercury is the closest planet to the Sun. Since it never strays far in the sky from the Sun’s glare, early astronomers had a difficult time viewing it, and considered it a "wandering star" appearing just before sunrise or just after sunset. Mercury travels around the Sun faster than any other planet ...
... Mercury is the closest planet to the Sun. Since it never strays far in the sky from the Sun’s glare, early astronomers had a difficult time viewing it, and considered it a "wandering star" appearing just before sunrise or just after sunset. Mercury travels around the Sun faster than any other planet ...
10-Jets and outflows
... 1 pc has grown at the speed of 10 km s−1 , then it must be 105 years old, comparable to the age of a Class I protostar. In general, outflow sizes range from under 0.1 pc to several parsecs. Furthermore, outflow speeds range from a few km s−1 up to about 100 km s−1 . Therefore, kinematic ages take on ...
... 1 pc has grown at the speed of 10 km s−1 , then it must be 105 years old, comparable to the age of a Class I protostar. In general, outflow sizes range from under 0.1 pc to several parsecs. Furthermore, outflow speeds range from a few km s−1 up to about 100 km s−1 . Therefore, kinematic ages take on ...
Stellarium User Guide - Skolekonsulenterne.dk
... also notice that the stars have started to move slightly across the sky. If it’s daytime you might be able to see the sun moving (but it’s less apparent than the movement of the stars). Increase the rate at which time passes again by clicking on the button a third time. Now time is really flying! Le ...
... also notice that the stars have started to move slightly across the sky. If it’s daytime you might be able to see the sun moving (but it’s less apparent than the movement of the stars). Increase the rate at which time passes again by clicking on the button a third time. Now time is really flying! Le ...
Origin of the Structure of the Kuiper Belt during a Dynamical
... observed orbital distribution of the Kuiper belt and that expected from the sculpting model (including observational biases) has never been done. Third, and most importantly, our view of the evolution of the giant planets’ orbits has changed radically. Last year, we proposed a new comprehensive scen ...
... observed orbital distribution of the Kuiper belt and that expected from the sculpting model (including observational biases) has never been done. Third, and most importantly, our view of the evolution of the giant planets’ orbits has changed radically. Last year, we proposed a new comprehensive scen ...
Super-Earth and Sub-Neptune Exoplanets: a First Look from the
... outward from the edge of our homey little planet. Telescope domes at my back, I have watched the Sun glow red as it approached secz = ∞ and finally set below the horizon. From Mount Hopkins, I have seen the shadows of flowering ocotillo plants (Fouquieria splendens) grow long against the desert. Fro ...
... outward from the edge of our homey little planet. Telescope domes at my back, I have watched the Sun glow red as it approached secz = ∞ and finally set below the horizon. From Mount Hopkins, I have seen the shadows of flowering ocotillo plants (Fouquieria splendens) grow long against the desert. Fro ...
vortices - University of Toronto Physics
... In this simple picture the core is like a string, in which the superfluid density goes to zero at the origin - the core has a finite diameter, because the singularity in the phase cannot persist in bulk superfluid. In He-4 this diameter is very small (only about 1 Angstrom!), but in other superfluid ...
... In this simple picture the core is like a string, in which the superfluid density goes to zero at the origin - the core has a finite diameter, because the singularity in the phase cannot persist in bulk superfluid. In He-4 this diameter is very small (only about 1 Angstrom!), but in other superfluid ...
PPT presentation
... found that the PN and HII region abundances of oxygen and neon agreed within the same galaxy but that the PN nitrogen was enhanced by 0.9 dex in the SMC and LMC. Interpreted as due to CN cycle processing of almost all of the original carbon into nitrogen at the time of the first dredge-up. This proc ...
... found that the PN and HII region abundances of oxygen and neon agreed within the same galaxy but that the PN nitrogen was enhanced by 0.9 dex in the SMC and LMC. Interpreted as due to CN cycle processing of almost all of the original carbon into nitrogen at the time of the first dredge-up. This proc ...
The Evolution of Molecular Clouds
... collect gas into giant molecular clouds must then be about 30 Myr. A similar estimate for the solar neighborhood, where the timescales are somewhat longer than the Galactic average, yields a formation timescale for molecular clouds of about 50 Myr (Larson 1991a, 1992b). Note that this estimated for ...
... collect gas into giant molecular clouds must then be about 30 Myr. A similar estimate for the solar neighborhood, where the timescales are somewhat longer than the Galactic average, yields a formation timescale for molecular clouds of about 50 Myr (Larson 1991a, 1992b). Note that this estimated for ...
The Gould Belt
... the age of the sample, and ranges from 130◦ to 180◦ according to various estimates. The spatial distribution of the stars is highly nonuniform; a significant drop in their density is observed at a radius of ≈80 pc from the center, i.e., the entire system has a donut shape. The well-known diffuse clust ...
... the age of the sample, and ranges from 130◦ to 180◦ according to various estimates. The spatial distribution of the stars is highly nonuniform; a significant drop in their density is observed at a radius of ≈80 pc from the center, i.e., the entire system has a donut shape. The well-known diffuse clust ...
- Spiral - Imperial College London
... synoptic observations of Sun-like stars at the Lowell observatory (Lockwood et al. 1992). Lockwood et al. (1997) selected 41 program stars bracketing the Sun in temperature and mean chromospheric activity (34 of these stars were also included in the Mount Wilson survey) and started their regular pho ...
... synoptic observations of Sun-like stars at the Lowell observatory (Lockwood et al. 1992). Lockwood et al. (1997) selected 41 program stars bracketing the Sun in temperature and mean chromospheric activity (34 of these stars were also included in the Mount Wilson survey) and started their regular pho ...
EXPOSITION OF TIME
... however, to presume, that the Universe had been created before the Big Bang. The expanding model does not exclude a creator, but it limits the time when the job could have been done… Some people think that science should only concern those laws of physics that describe the development of the Univers ...
... however, to presume, that the Universe had been created before the Big Bang. The expanding model does not exclude a creator, but it limits the time when the job could have been done… Some people think that science should only concern those laws of physics that describe the development of the Univers ...
2004 SA Orlov
... The proposed model of gravitation, cosmology and cosmogony is based on an assumption that the initial cause of rotations of all the celestial objects or their systems in the Universe is the vortex rotation (in corresponding space regions) of a gaseous cosmic-space medium, viz. the ether. The ether r ...
... The proposed model of gravitation, cosmology and cosmogony is based on an assumption that the initial cause of rotations of all the celestial objects or their systems in the Universe is the vortex rotation (in corresponding space regions) of a gaseous cosmic-space medium, viz. the ether. The ether r ...
Starburst Galaxies - Beck-Shop
... over 100 solar masses (beyond which stars become unstable). By far the majority of stars though are at the low-mass end of this range – 80% have masses less than that of the Sun. The higher mass stars are thus few and far between, but their brightnesses are out of all proportion greater than those o ...
... over 100 solar masses (beyond which stars become unstable). By far the majority of stars though are at the low-mass end of this range – 80% have masses less than that of the Sun. The higher mass stars are thus few and far between, but their brightnesses are out of all proportion greater than those o ...
GALAXIES 626
... (ii) Globular clusters - dense compact clusters distributed in the Galactic halo. Hubble image of the globular cluster M80. In the Milky Way, globular clusters are made up of old stars only. ...
... (ii) Globular clusters - dense compact clusters distributed in the Galactic halo. Hubble image of the globular cluster M80. In the Milky Way, globular clusters are made up of old stars only. ...
Introduction to Comets - Mr. Hill`s Science Website
... (from NASA: Amazing Space Online Exploration website) ...
... (from NASA: Amazing Space Online Exploration website) ...
The Moon Tilt Illusion - Penn Engineering
... high in the sky and the sun had set in the west one hour before this photo was taken. The moon is 45◦ above the horizon in the southeast, 80% illuminated by light from the sun striking the moon at an angle of 17◦ above the horizontal, as shown by the arrow drawn on the photograph. Our intuition (i.e ...
... high in the sky and the sun had set in the west one hour before this photo was taken. The moon is 45◦ above the horizon in the southeast, 80% illuminated by light from the sun striking the moon at an angle of 17◦ above the horizontal, as shown by the arrow drawn on the photograph. Our intuition (i.e ...
Document
... In the most popular theory, icy planetesimals in the primitive solar nebula that wandered close to Uranus or Neptune but not close enough to be captured by them were flung to great distances from the Sun, some to be lost from the solar system while others populated what was to become a great cloud o ...
... In the most popular theory, icy planetesimals in the primitive solar nebula that wandered close to Uranus or Neptune but not close enough to be captured by them were flung to great distances from the Sun, some to be lost from the solar system while others populated what was to become a great cloud o ...
Asteroids, Meteorites, and Comets
... bodies that could potentially collide with Earth, the solar system is viewed as a collection of objects with a whole continuum of sizes.The Sun is orbited by material that ranges in size from grains of interplanetary dust to the giant Jupiter, and the planets in their turn are orbited by moons from ...
... bodies that could potentially collide with Earth, the solar system is viewed as a collection of objects with a whole continuum of sizes.The Sun is orbited by material that ranges in size from grains of interplanetary dust to the giant Jupiter, and the planets in their turn are orbited by moons from ...
History of Solar System formation and evolution hypotheses
Ideas concerning the origin and fate of the world date from the earliest known writings; however, for almost all of that time, there was no attempt to link such theories to the existence of a ""Solar System"", simply because almost no one knew or believed that the Solar System, in the sense we now understand it, existed. The first step towards a theory of Solar System formation was the general acceptance of heliocentrism, the model which placed the Sun at the centre of the system and the Earth in orbit around it. This conception had been gestating for thousands of years, but was only widely accepted by the end of the 17th century. The first recorded use of the term ""Solar System"" dates from 1704.