Document
... 3. The halo. Old stars (including the globular clusters) and very dilute interstellar matter form a roughly spherical Galactic halo around the disk. The inner part of the halo is at least as large across as the disk, perhaps 60,000 light-years in radius. The gas in the inner halo is hot, 100,000 K, ...
... 3. The halo. Old stars (including the globular clusters) and very dilute interstellar matter form a roughly spherical Galactic halo around the disk. The inner part of the halo is at least as large across as the disk, perhaps 60,000 light-years in radius. The gas in the inner halo is hot, 100,000 K, ...
1957_boeke_cosmic view
... We all, children and grownups alike, are inclined to live in our own little world, in our immediate surroundings, or at any rate with our attention concentrated on those things with which we are directly in touch. We tend to forget how vast are the ranges of existing reality which our eyes cannot di ...
... We all, children and grownups alike, are inclined to live in our own little world, in our immediate surroundings, or at any rate with our attention concentrated on those things with which we are directly in touch. We tend to forget how vast are the ranges of existing reality which our eyes cannot di ...
Cosmic View The Universe in 40 Jumps
... We all, children and grownups alike, are inclined to live in our own little world, in our immediate surroundings, or at any rate with our attention concentrated on those things with which we are directly in touch. We tend to forget how vast are the ranges of existing reality which our eyes cannot di ...
... We all, children and grownups alike, are inclined to live in our own little world, in our immediate surroundings, or at any rate with our attention concentrated on those things with which we are directly in touch. We tend to forget how vast are the ranges of existing reality which our eyes cannot di ...
A Stargazers Guide to Astronomy
... system of waves. In empty space, light has a fixed speed and the wavelength can be measured. In the past 300 years, scientists have improved the way they measure the speed of light, and they have determined that it travels at nearly 299,792 kilometers, or 186,281 miles, per second. When we talk abou ...
... system of waves. In empty space, light has a fixed speed and the wavelength can be measured. In the past 300 years, scientists have improved the way they measure the speed of light, and they have determined that it travels at nearly 299,792 kilometers, or 186,281 miles, per second. When we talk abou ...
The Evolution of Galaxy - Tufts Institute of Cosmology
... mpelled by these mysteries, the pace of discovery in the study of clusters has accelerated over the past 40 years. Astronomers now know of some 10,000 of them. American astronomer George Abell compiled the first large list in the early 1950s, based on photographs of the entire northern sky taken at ...
... mpelled by these mysteries, the pace of discovery in the study of clusters has accelerated over the past 40 years. Astronomers now know of some 10,000 of them. American astronomer George Abell compiled the first large list in the early 1950s, based on photographs of the entire northern sky taken at ...
Quasars: Back to the Infant Universe
... Time of rise and fall in quasar brightness tells us its maximum size (= time to vary x the speed of light) ...
... Time of rise and fall in quasar brightness tells us its maximum size (= time to vary x the speed of light) ...
REVIEWS 18 years of science with the Hubble Space Telescope Julianne J. Dalcanton
... scales of a given system. Are we observing a faint object that happens to be close, or a bright object that is much farther away? Moreover, even when we can make reasonable assumptions about an object’s distance, we frequently lack the precision needed for critical cosmological tests. Over the past ...
... scales of a given system. Are we observing a faint object that happens to be close, or a bright object that is much farther away? Moreover, even when we can make reasonable assumptions about an object’s distance, we frequently lack the precision needed for critical cosmological tests. Over the past ...
Overview and historical perspective on Cosmology
... Gamma ray bursts from stars falling into black holes, or neutron star pairs, etc., with jets aimed at us? z=1, expansion slows galaxy mergers, star formation diminishes, quasar numbers decrease, major infalls to Milky Way stop, Milky Way takes present shape Sun and Earth form, 4.5 Gyr ago (z ~ 1/3), ...
... Gamma ray bursts from stars falling into black holes, or neutron star pairs, etc., with jets aimed at us? z=1, expansion slows galaxy mergers, star formation diminishes, quasar numbers decrease, major infalls to Milky Way stop, Milky Way takes present shape Sun and Earth form, 4.5 Gyr ago (z ~ 1/3), ...
Galaxies (Professor Powerpoint)
... Now consider the Milky Way galaxy. Using radio observations, it is possible to measure the orbital speed as a function of the distance from the center. ...
... Now consider the Milky Way galaxy. Using radio observations, it is possible to measure the orbital speed as a function of the distance from the center. ...
THE SPACE WEATHER OF PROXIMA CENTAURI b
... The MHD model of the stellar corona, wind, and magnetic field of Proxima, driven using the scaled GJ51 magnetogram, was computed using BATS-R-US. We assumed a stellar rotation period of 83 days (Benedict et al. 1998). Unlike the case of rapidly rotating stars, where rotation results in azimuthal wra ...
... The MHD model of the stellar corona, wind, and magnetic field of Proxima, driven using the scaled GJ51 magnetogram, was computed using BATS-R-US. We assumed a stellar rotation period of 83 days (Benedict et al. 1998). Unlike the case of rapidly rotating stars, where rotation results in azimuthal wra ...
Chapter 31: Galaxies and the Universe
... Variable Stars In the 1920s, astronomers mapped out the locations of globular clusters. These huge, spherical star clusters are located above or below the plane of the galactic disk, shown in Figure 31-1. Astronomers estimated the distances to the clusters by identifying variable stars in them. Vari ...
... Variable Stars In the 1920s, astronomers mapped out the locations of globular clusters. These huge, spherical star clusters are located above or below the plane of the galactic disk, shown in Figure 31-1. Astronomers estimated the distances to the clusters by identifying variable stars in them. Vari ...
Interpretation of the Helix Planetary Nebula using Hydro
... signatures (Bershadskii and Sreenivasan 2002) in the cosmic microwave background temperature anisotropies. From Jeans’ theory without Jeans’ swindle, a gravitational condensation on an acoustical density maximum rapidly becomes a non-acoustical density maximum because the gravitationally accreted ma ...
... signatures (Bershadskii and Sreenivasan 2002) in the cosmic microwave background temperature anisotropies. From Jeans’ theory without Jeans’ swindle, a gravitational condensation on an acoustical density maximum rapidly becomes a non-acoustical density maximum because the gravitationally accreted ma ...
Additional Cosmology Images
... NASA's Hubble Space Telescope has captured the most detailed images to date of the open star clusters NGC 265 and NGC 290 in the Small Magellanic Cloud — two sparkling sets of gemstones in the southern sky. These images, taken with Hubble's Advanced Camera for Surveys, show a myriad of stars in cry ...
... NASA's Hubble Space Telescope has captured the most detailed images to date of the open star clusters NGC 265 and NGC 290 in the Small Magellanic Cloud — two sparkling sets of gemstones in the southern sky. These images, taken with Hubble's Advanced Camera for Surveys, show a myriad of stars in cry ...
Potential for Life on the Terrestrial Planets
... available data suggest that more massive and slightly larger planets compared to Earth with orbital distances > 0.02 AU (around G stars) are more likely mini-Neptunes than a pure rocky planet with a tiny Earth-like atmosphere, but the present error bars in the radius-mass relation are too large and ...
... available data suggest that more massive and slightly larger planets compared to Earth with orbital distances > 0.02 AU (around G stars) are more likely mini-Neptunes than a pure rocky planet with a tiny Earth-like atmosphere, but the present error bars in the radius-mass relation are too large and ...
6th Grade Science
... velocity on the orbit of celestial objects. • Scale, proportion, and quantity; such as solar system, universe, galaxy, size of microorganisms. • Systems and system models; such as solar system, rotation, revolution, constellations. • Energy and matter: Flows, cycles, and conservation; such as heat t ...
... velocity on the orbit of celestial objects. • Scale, proportion, and quantity; such as solar system, universe, galaxy, size of microorganisms. • Systems and system models; such as solar system, rotation, revolution, constellations. • Energy and matter: Flows, cycles, and conservation; such as heat t ...
The evolution of organic matter in space
... stellar explosions by neutron absorption (s and r processes). In this phase, no equilibrium can be reached: the stars undergo mass loss either in a smooth way or in violent way, leading to the enrichment of the interstellar medium. Analytical arguments [2], as well as numerical simulations [3], show ...
... stellar explosions by neutron absorption (s and r processes). In this phase, no equilibrium can be reached: the stars undergo mass loss either in a smooth way or in violent way, leading to the enrichment of the interstellar medium. Analytical arguments [2], as well as numerical simulations [3], show ...
Cosmological Implications of Trace
... net local charge imbalances at the level where these imbalances generate electrostatic Coulomb forces of similar size to gravitational attractions, associated with a net charge-to-mass ratio of order CG = 8.6167 × 10−11 C/kg, or, alternatively expressed, a net proton or electron imbalance of 1 extr ...
... net local charge imbalances at the level where these imbalances generate electrostatic Coulomb forces of similar size to gravitational attractions, associated with a net charge-to-mass ratio of order CG = 8.6167 × 10−11 C/kg, or, alternatively expressed, a net proton or electron imbalance of 1 extr ...
Untitled
... story. According to many experts along with Hawking, if there is a scientific census of the rest of the Milky Way and beyond, the odds in favor of extra-terrestrial life's existence would rise dramatically. With all the speculations and the possibilities, what the extra-terrestrial life-form might a ...
... story. According to many experts along with Hawking, if there is a scientific census of the rest of the Milky Way and beyond, the odds in favor of extra-terrestrial life's existence would rise dramatically. With all the speculations and the possibilities, what the extra-terrestrial life-form might a ...
Galaxies
... Galaxy mass measurements show that galaxies need between 3 and 10 times more mass than can be observed to explain their rotation curves. The discrepancy is even larger in galaxy clusters, which need 10 to 100 times more mass. The total needed is more than the sum of the dark matter associated with e ...
... Galaxy mass measurements show that galaxies need between 3 and 10 times more mass than can be observed to explain their rotation curves. The discrepancy is even larger in galaxy clusters, which need 10 to 100 times more mass. The total needed is more than the sum of the dark matter associated with e ...
RAL Space brochure - Science and Technology Facilities Council
... may carry 1,000,000,000 tonnes of gas into space at several hundred km/s. When these clouds engulf Earth they can disrupt power, navigation, communication and satellite control systems. ...
... may carry 1,000,000,000 tonnes of gas into space at several hundred km/s. When these clouds engulf Earth they can disrupt power, navigation, communication and satellite control systems. ...
Document
... from an extremely dense and hot state, the Big Bang, 13.7 Gyr ago, expanding and cooling ever since. In the beginning, it consisted of an almost homogeneous plasma without heavy chemical elements and with only very tiny fluctuations in the density profile. It was very different from today’s structur ...
... from an extremely dense and hot state, the Big Bang, 13.7 Gyr ago, expanding and cooling ever since. In the beginning, it consisted of an almost homogeneous plasma without heavy chemical elements and with only very tiny fluctuations in the density profile. It was very different from today’s structur ...
Master SPACE - University of Science and Technology of Hanoi
... convection and radiation), heat equation, Fourier’s law, black body radiation, StefanBoltzmann law, emissivity and absorptivity, Kirchhoff's law of thermal radiation, thermal design and control of satellites, forced convection, introduction to finite element methods ...
... convection and radiation), heat equation, Fourier’s law, black body radiation, StefanBoltzmann law, emissivity and absorptivity, Kirchhoff's law of thermal radiation, thermal design and control of satellites, forced convection, introduction to finite element methods ...
Outer space
Outer space, or just space, is the void that exists between celestial bodies, including the Earth. It is not completely empty, but consists of a hard vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium as well as electromagnetic radiation, magnetic fields, neutrinos, dust and cosmic rays. The baseline temperature, as set by the background radiation from the Big Bang, is 2.7 kelvin (K). Plasma with a number density of less than one hydrogen atom per cubic metre and a temperature of millions of kelvin in the space between galaxies accounts for most of the baryonic (ordinary) matter in outer space; local concentrations have condensed into stars and galaxies. In most galaxies, observations provide evidence that 90% of the mass is in an unknown form, called dark matter, which interacts with other matter through gravitational but not electromagnetic forces. Data indicates that the majority of the mass-energy in the observable Universe is a poorly understood vacuum energy of space which astronomers label dark energy. Intergalactic space takes up most of the volume of the Universe, but even galaxies and star systems consist almost entirely of empty space.There is no firm boundary where space begins. However the Kármán line, at an altitude of 100 km (62 mi) above sea level, is conventionally used as the start of outer space in space treaties and for aerospace records keeping. The framework for international space law was established by the Outer Space Treaty, which was passed by the United Nations in 1967. This treaty precludes any claims of national sovereignty and permits all states to freely explore outer space. Despite the drafting of UN resolutions for the peaceful uses of outer space, anti-satellite weapons have been tested in Earth orbit.Humans began the physical exploration of space during the 20th century with the advent of high-altitude balloon flights, followed by manned rocket launches. Earth orbit was first achieved by Yuri Gagarin of the Soviet Union in 1961 and unmanned spacecraft have since reached all of the known planets in the Solar System. Due to the high cost of getting into space, manned spaceflight has been limited to low Earth orbit and the Moon.Outer space represents a challenging environment for human exploration because of the dual hazards of vacuum and radiation. Microgravity also has a negative effect on human physiology that causes both muscle atrophy and bone loss. In addition to these health and environmental issues, the economic cost of putting objects, including humans, into space is high.