YEAR - University of Maryland Astronomy
... Not Stars The Sun's Magnetic Field How Stars Form X-Rays and Gamma Rays on the Sun The Problem with Mars Fasten Your Seatbelts! The Bumpy Ride to Star Formation Looking at Other Wavelengths: A Survey of Astronomy Observatories from Radio to Gamma Rays Gravity, From Here to Eternity Have you seen the ...
... Not Stars The Sun's Magnetic Field How Stars Form X-Rays and Gamma Rays on the Sun The Problem with Mars Fasten Your Seatbelts! The Bumpy Ride to Star Formation Looking at Other Wavelengths: A Survey of Astronomy Observatories from Radio to Gamma Rays Gravity, From Here to Eternity Have you seen the ...
3. Cosmology and the Origin and Evolution of Galaxies
... more than 60% of the brightest mm galaxies lie between redshifts z =1.8 - 3.58,9. If we take into account the small fraction (< 10%) of the sub-mm background that corresponds to these bright sub-mm sources, however, it is immediately apparent that some other method has to be found in order to measur ...
... more than 60% of the brightest mm galaxies lie between redshifts z =1.8 - 3.58,9. If we take into account the small fraction (< 10%) of the sub-mm background that corresponds to these bright sub-mm sources, however, it is immediately apparent that some other method has to be found in order to measur ...
SUPERNOVA REMNANT SHOCKS IN AN INHOMOGENEOUS
... (McKee and Ostriker 1977). Although fh is high in the local ISM, its value at a typical point in the galactic disk remains controversial (Cox 1987). It is quite likely that fh depends on both the nature of the galaxy and the location within it. In principle, observations of SNRs could provide the me ...
... (McKee and Ostriker 1977). Although fh is high in the local ISM, its value at a typical point in the galactic disk remains controversial (Cox 1987). It is quite likely that fh depends on both the nature of the galaxy and the location within it. In principle, observations of SNRs could provide the me ...
Synthesis of Complex Organic Molecules
... About 100 seconds after the Big Bang, protons, neutrons and electrons existed in photon radiation at a temperature of about of about 109 K. Hydrogen, deuterium and helium could then form. Besides H and He, the only other element that could form via collisions during this nucleosynthesis epoch was li ...
... About 100 seconds after the Big Bang, protons, neutrons and electrons existed in photon radiation at a temperature of about of about 109 K. Hydrogen, deuterium and helium could then form. Besides H and He, the only other element that could form via collisions during this nucleosynthesis epoch was li ...
STELLAR ABLATION OF PLANETARY ATMOSPHERES
... particle driven ion heating, parallel electric field, and other processes occurring at altitudes from 1000 km upward [André et al., 1998] then supply the additional energy needed, particularly for O+ to escape the Earth’s gravitational well (about 10 eV). Wu et al. [1999] has systematically investi ...
... particle driven ion heating, parallel electric field, and other processes occurring at altitudes from 1000 km upward [André et al., 1998] then supply the additional energy needed, particularly for O+ to escape the Earth’s gravitational well (about 10 eV). Wu et al. [1999] has systematically investi ...
Zhu Qualifier Solutions - University of Toronto Astronomy
... 3.1.3. Why are the lower and upper limits of the IMF poorly understood compared to that of the middle (several M stars)? What constraints are there? 3.1.4. What’s the difference between a field and stellar cluster IMF? 3.1.5. How do you determine an a present-day mass function (PDMF) from an IMF? 3 ...
... 3.1.3. Why are the lower and upper limits of the IMF poorly understood compared to that of the middle (several M stars)? What constraints are there? 3.1.4. What’s the difference between a field and stellar cluster IMF? 3.1.5. How do you determine an a present-day mass function (PDMF) from an IMF? 3 ...
arXiv:astro-ph/9909369 v1 22 Sep 1999
... in the Antennae (Vigroux et al., 1996), but is now observed also in Mrk 171 (Gallais et al., 1999), NGC 253 (Keto et al., 1999), NGC 5253 (Crowther et al., 1999), or Arp 220 (Soifer et al., 1999). A plausible interpretation of these sources is that they are buried super-star-clusters, that will late ...
... in the Antennae (Vigroux et al., 1996), but is now observed also in Mrk 171 (Gallais et al., 1999), NGC 253 (Keto et al., 1999), NGC 5253 (Crowther et al., 1999), or Arp 220 (Soifer et al., 1999). A plausible interpretation of these sources is that they are buried super-star-clusters, that will late ...
2004 SA Orlov
... In modern astrophysics, the star evolution is considered according to the following scheme: - at the initial stage, the appearance of dense clouds of gas and dust occurs, from which, under the action of the own gravitation, a compressing proto-star is formed. Then, an ordinary star is formed, and af ...
... In modern astrophysics, the star evolution is considered according to the following scheme: - at the initial stage, the appearance of dense clouds of gas and dust occurs, from which, under the action of the own gravitation, a compressing proto-star is formed. Then, an ordinary star is formed, and af ...
Astro Review - Parkway C-2
... 64. The relatively small, rocky bodies generally found orbiting between Mars and Jupiter are known as ____. 65. Which force is most responsible for the formation of a star? 66. Gamma rays, X-rays, visible light, and radio waves are all types of ____. ...
... 64. The relatively small, rocky bodies generally found orbiting between Mars and Jupiter are known as ____. 65. Which force is most responsible for the formation of a star? 66. Gamma rays, X-rays, visible light, and radio waves are all types of ____. ...
mg_colloq - University of Massachusetts Amherst
... • Include the oldest, most massive galaxies • Formed the bulk of their stellar mass at high redshift, on short time scale: ≈90% at z>2 (Renzini 2006) • Probes of the physics of early star formation • Evolved passively since ...
... • Include the oldest, most massive galaxies • Formed the bulk of their stellar mass at high redshift, on short time scale: ≈90% at z>2 (Renzini 2006) • Probes of the physics of early star formation • Evolved passively since ...
story of telescope
... book challenging the ancient ideas about the solar system. In the Copernican system, the Earth rotated around its axis once a day and it revolved around the Sun once a year. This model explained the retrograde motion in an elegant manner, without using any epicycles. According to the Copernican syst ...
... book challenging the ancient ideas about the solar system. In the Copernican system, the Earth rotated around its axis once a day and it revolved around the Sun once a year. This model explained the retrograde motion in an elegant manner, without using any epicycles. According to the Copernican syst ...
Super-solar Metal Abundances in Two Galaxies at ζ ∼ 3.57
... Zn as a function of Zn ii column density for G0 and G1, other GRB-DLAs and QSO-DLAs. For G1 we derive [S/Zn] = −0.33 ± 0.04 and [Si/Zn] = −0.72 ± 0.06. Anomalous relative abundances have been found before in high-z absorption line systems. In QSO-DLAs, significant [S/Zn] < 0 is observed for about ha ...
... Zn as a function of Zn ii column density for G0 and G1, other GRB-DLAs and QSO-DLAs. For G1 we derive [S/Zn] = −0.33 ± 0.04 and [Si/Zn] = −0.72 ± 0.06. Anomalous relative abundances have been found before in high-z absorption line systems. In QSO-DLAs, significant [S/Zn] < 0 is observed for about ha ...
Galaxy Evolution
... ELLIPTICAL GALAXIES consist only of the bulge component and have no disk. LENTICULAR GALAXIES are essentially ellipticals with a very thin, often almost invisible disk, which gives them the shape of a lentil. SPIRAL GALAXIES have both a bulge and a disk with spiral arms. If a bar is present, this co ...
... ELLIPTICAL GALAXIES consist only of the bulge component and have no disk. LENTICULAR GALAXIES are essentially ellipticals with a very thin, often almost invisible disk, which gives them the shape of a lentil. SPIRAL GALAXIES have both a bulge and a disk with spiral arms. If a bar is present, this co ...
Galaxy Evolution Encyclopedia of Astronomy & Astrophysics eaa.iop.org Mauro Giavalisco
... ELLIPTICAL GALAXIES consist only of the bulge component and have no disk. LENTICULAR GALAXIES are essentially ellipticals with a very thin, often almost invisible disk, which gives them the shape of a lentil. SPIRAL GALAXIES have both a bulge and a disk with spiral arms. If a bar is present, this co ...
... ELLIPTICAL GALAXIES consist only of the bulge component and have no disk. LENTICULAR GALAXIES are essentially ellipticals with a very thin, often almost invisible disk, which gives them the shape of a lentil. SPIRAL GALAXIES have both a bulge and a disk with spiral arms. If a bar is present, this co ...
Exploring the Most Bizarre Ideas in Cosmology Astronomers
... Anderson, however, also raises the suggestion that maybe Thales was really arguing that the chief property of water— fluidity—rather than literal water per se, was the real underlying principle of the universe. Everything is therefore "like" or "a form of" water rather than water in the usual sense ...
... Anderson, however, also raises the suggestion that maybe Thales was really arguing that the chief property of water— fluidity—rather than literal water per se, was the real underlying principle of the universe. Everything is therefore "like" or "a form of" water rather than water in the usual sense ...
An Expanded View of the Universe
... What was the nature of the first stars? When did the first galaxies assemble and what were their properties? When did galaxies assemble into larger scale structures, shaping the distribution of matter as we see it today? ...
... What was the nature of the first stars? When did the first galaxies assemble and what were their properties? When did galaxies assemble into larger scale structures, shaping the distribution of matter as we see it today? ...
the origin of the hubble sequence - Yale Astronomy
... star formation rate per unit area is then proportional to μ2 , which is similar to the quadratic dependence on volume density originally proposed by Schmidt (1959). This prediction does not, however, provide any ready basis for understanding why the gas depletion timescale should increase along the ...
... star formation rate per unit area is then proportional to μ2 , which is similar to the quadratic dependence on volume density originally proposed by Schmidt (1959). This prediction does not, however, provide any ready basis for understanding why the gas depletion timescale should increase along the ...
A new view of galaxy evolution
... the universe is in a “dark” form that cannot be period. The critical aspect of this, however, is detected directly. The nature of this dark mat- that very little to no additional mass is added to ter, however, has a direct and perhaps primary a galaxy once it forms in the very early universe. role i ...
... the universe is in a “dark” form that cannot be period. The critical aspect of this, however, is detected directly. The nature of this dark mat- that very little to no additional mass is added to ter, however, has a direct and perhaps primary a galaxy once it forms in the very early universe. role i ...
Plotting the Rotation Curve of M31
... approaching or receding limb of the galaxy and the velocity of rotation at that point. A velocity vs radius graph is plotted and compared with their predicted result. Equipment: calculator, ruler, graph paper (if needed) Questions to ask the class before the activity: What is the Universe composed o ...
... approaching or receding limb of the galaxy and the velocity of rotation at that point. A velocity vs radius graph is plotted and compared with their predicted result. Equipment: calculator, ruler, graph paper (if needed) Questions to ask the class before the activity: What is the Universe composed o ...
EXPOSITION OF TIME
... bonds, which connect the history of our planet and pursuance of the earth civilisation despite the differences among nations, races, and religions. The mystery of time lies in the fact, that it is omnipresent and still does not take the slightest space. It can be measured, but not seen. It cannot be ...
... bonds, which connect the history of our planet and pursuance of the earth civilisation despite the differences among nations, races, and religions. The mystery of time lies in the fact, that it is omnipresent and still does not take the slightest space. It can be measured, but not seen. It cannot be ...
EOS Experts Guide - by topic and by name
... Brief biographies of scientists from the three EOS centers — the Earth Systems Research Center, Ocean Process Analysis Laboratory, and the Space Science Center — provide areas of specialty, research interests, credentials, and contact information. Experts can also be found by means of an alphabetica ...
... Brief biographies of scientists from the three EOS centers — the Earth Systems Research Center, Ocean Process Analysis Laboratory, and the Space Science Center — provide areas of specialty, research interests, credentials, and contact information. Experts can also be found by means of an alphabetica ...
8 Comets: Potential Sources of Prebiotic Molecules for the
... Cometary dust particles disperse more or less rapidly into the interplanetary space, according to their shape, nature and initial velocity. Some of them cross the path of the Earth; if large enough they produce meteors. One can get an idea of cometary dust particles by looking at particles collected ...
... Cometary dust particles disperse more or less rapidly into the interplanetary space, according to their shape, nature and initial velocity. Some of them cross the path of the Earth; if large enough they produce meteors. One can get an idea of cometary dust particles by looking at particles collected ...
Measuring distances to the edge of the local group
... 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 inner planets condensed within massive gaseous envelopes similar to present-day gas gi ...
... 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 inner planets condensed within massive gaseous envelopes similar to present-day gas gi ...
Venus express: Highlights of the nominal mission - HAL
... successful Mars Express bus—a 600 kg 3-axis stabilized platform with two body-fixed telecommunication antennas (Fig. 1). The spacecraft is described in detail by Svedhem et al. (2007a, 2008). Most of the subsystems and payloads are mounted on its walls and on panels inside the bus, while ASPERA and ...
... successful Mars Express bus—a 600 kg 3-axis stabilized platform with two body-fixed telecommunication antennas (Fig. 1). The spacecraft is described in detail by Svedhem et al. (2007a, 2008). Most of the subsystems and payloads are mounted on its walls and on panels inside the bus, while ASPERA and ...
Module 11.1.1: Galaxies: Morphology and the Hubble Sequence
... of those. And those are sort of the last pre-‐modern compilations of galaxian data. Nowadays, it's all done in fully automated objective fashion from digital sky surveys, and modern catalogs of ...
... of those. And those are sort of the last pre-‐modern compilations of galaxian data. Nowadays, it's all done in fully automated objective fashion from digital sky surveys, and modern catalogs of ...
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.