22 Years of a Pulsar
... The future • Continue monitoring system at Parkes • Determine if measured values of xdot, omegadot pass the test • Does the proper motion measurement agree with LBA ...
... The future • Continue monitoring system at Parkes • Determine if measured values of xdot, omegadot pass the test • Does the proper motion measurement agree with LBA ...
Constellation Paper - Matt Hape`s Portfolio
... The Pisces constellation is clearly a very interesting and important thing in space. It contains many things that are scientifically significant, but there are two things in particular that make the Pisces constellation unique. The first object of interest is a Messier object known as Messier 74, o ...
... The Pisces constellation is clearly a very interesting and important thing in space. It contains many things that are scientifically significant, but there are two things in particular that make the Pisces constellation unique. The first object of interest is a Messier object known as Messier 74, o ...
A Walk through the Southern Sky: A Guide to Stars and
... Rigel is actually thousands of times brighter than Sirius. It appears fainter because it is over a thousand light years away, while Sirius is only 81⁄2 light years from us. We measure the brightness of the stars as seen with the naked eye on a scale called the magnitude scale. Hipparchus, a Greek as ...
... Rigel is actually thousands of times brighter than Sirius. It appears fainter because it is over a thousand light years away, while Sirius is only 81⁄2 light years from us. We measure the brightness of the stars as seen with the naked eye on a scale called the magnitude scale. Hipparchus, a Greek as ...
Superbubble Activity in Star-Forming Galaxies M. S. Oey
... and confirmed the existence of C iv and Si iv absorption in all cases. A stringent test of the adiabatic model is to compare the predicted and observed shell kinematics in cases where the input mechanical power and other parameters are well-constrained. This was carried out for eight, young, wind-do ...
... and confirmed the existence of C iv and Si iv absorption in all cases. A stringent test of the adiabatic model is to compare the predicted and observed shell kinematics in cases where the input mechanical power and other parameters are well-constrained. This was carried out for eight, young, wind-do ...
Have You Seen Canopus Tonight?
... other bright stars on the sky, about 310 light years by current estimates. However, other very bright looking stars as Rigel (900 light years?) or Deneb (1,000 light years?) are more distant. Nevertheless, this still makes Canopus a splendid and imposing star as we shall see. We know, too, that Cano ...
... other bright stars on the sky, about 310 light years by current estimates. However, other very bright looking stars as Rigel (900 light years?) or Deneb (1,000 light years?) are more distant. Nevertheless, this still makes Canopus a splendid and imposing star as we shall see. We know, too, that Cano ...
The Milky Way as a galaxy
... the angular position of a source relative to the Galactic disk. However, we will now introduce another three-dimensional coordinate system for the description of the Milky Way geometry that will prove very convenient in the study of its kinematic and dynamic properties. It is a cylindrical coordinat ...
... the angular position of a source relative to the Galactic disk. However, we will now introduce another three-dimensional coordinate system for the description of the Milky Way geometry that will prove very convenient in the study of its kinematic and dynamic properties. It is a cylindrical coordinat ...
Teil 2
... orbital motion, i.e., they appear centred at the central meridian during the respective quadrature phases, thus are not facing each other as would be the case for a hypothetical reflection effect. The leading hemispheres on both components appear with an effectively lower temperature than the traili ...
... orbital motion, i.e., they appear centred at the central meridian during the respective quadrature phases, thus are not facing each other as would be the case for a hypothetical reflection effect. The leading hemispheres on both components appear with an effectively lower temperature than the traili ...
neutron star
... BLACK HOLE VERIFICATION • We need to measure mass by: — Using orbital properties of a companion — Measuring the velocity and distance of orbiting gas ...
... BLACK HOLE VERIFICATION • We need to measure mass by: — Using orbital properties of a companion — Measuring the velocity and distance of orbiting gas ...
Essential physics of early galaxy formation
... further star formation. As halos build-up mass with time, their DM potential well can sustain much larger star formation rates (SFR) without losing gas. This naturally implies that, at any given time, there is a limiting star formation efficiency such that the energy produced by newly-formed stars i ...
... further star formation. As halos build-up mass with time, their DM potential well can sustain much larger star formation rates (SFR) without losing gas. This naturally implies that, at any given time, there is a limiting star formation efficiency such that the energy produced by newly-formed stars i ...
25 Years of the Hubble Space Telescope - Speaker
... with Hubble’s Advanced Camera for Surveys. It is a 50-light-year-wide view of the central region of the Carina Nebula, where a maelstrom of star birth -- and death -- is taking place. The nebula is sculpted by the action of outflowing winds and scorching ultraviolet radiation from the monster stars ...
... with Hubble’s Advanced Camera for Surveys. It is a 50-light-year-wide view of the central region of the Carina Nebula, where a maelstrom of star birth -- and death -- is taking place. The nebula is sculpted by the action of outflowing winds and scorching ultraviolet radiation from the monster stars ...
the stebbins galaxy: the origins of interstellar medium studies
... 1) The distribution of globular clusters, presumed to be centered around the center of mass of the Galaxy, shows the Sun to be far from that center. 2) The measured distances to globular clusters show the Galaxy to be about 70,000 parsecs (200,000 light-years or so) in diameter (Shapley, 1930a: 221) ...
... 1) The distribution of globular clusters, presumed to be centered around the center of mass of the Galaxy, shows the Sun to be far from that center. 2) The measured distances to globular clusters show the Galaxy to be about 70,000 parsecs (200,000 light-years or so) in diameter (Shapley, 1930a: 221) ...
Sample pages 1 PDF
... mirror on Mt. Palomar in 1948. Currently, 13 telescopes with diameter above 8 m are in use, and planning for telescopes with 30 m diameter or more has begun. In recent years, our capabilities to find very distant, and thus very dim, objects and to examine them in detail have improved immensely thank ...
... mirror on Mt. Palomar in 1948. Currently, 13 telescopes with diameter above 8 m are in use, and planning for telescopes with 30 m diameter or more has begun. In recent years, our capabilities to find very distant, and thus very dim, objects and to examine them in detail have improved immensely thank ...
Science with IMACS on Magellan
... gradients in the halos of nearby brighter galaxies such as those of the Sculptor group. They are particularly interested in using the tip of the red giant branch as a distance indicator to nearby galaxies with a wide range of metal abundances, as a check of possible dependences of Cepheid-based dist ...
... gradients in the halos of nearby brighter galaxies such as those of the Sculptor group. They are particularly interested in using the tip of the red giant branch as a distance indicator to nearby galaxies with a wide range of metal abundances, as a check of possible dependences of Cepheid-based dist ...
Chapter 17--Star Stuff
... The length of time from the formation of a protostar to the birth of a main-sequence star depends on the star’s mass. Massive stars do everything faster. The contraction of a high-mass protostar into a main-sequence star may take only a million years or less. A star like our Sun takes about 50 milli ...
... The length of time from the formation of a protostar to the birth of a main-sequence star depends on the star’s mass. Massive stars do everything faster. The contraction of a high-mass protostar into a main-sequence star may take only a million years or less. A star like our Sun takes about 50 milli ...
Wolf-Rayet Stars
... to identify, by spectroscopic observations, even at large distances. W-R stars are divided into three broad spectroscopic classes (WN, WC and WO) based on the emission lines present in their spectrum. WN stars show emission lines predominantly of helium and nitrogen, although emission due to carbon, ...
... to identify, by spectroscopic observations, even at large distances. W-R stars are divided into three broad spectroscopic classes (WN, WC and WO) based on the emission lines present in their spectrum. WN stars show emission lines predominantly of helium and nitrogen, although emission due to carbon, ...
Hidden57_rf
... the narrow band of light that could penetrate the Earth’s atmosphere and was visible to our eyes or to sensitive photographic plates loaded at the focus of increasingly large telescopes. With these resources alone, the discoveries were still stupendous: the mapping of our Solar System, the identific ...
... the narrow band of light that could penetrate the Earth’s atmosphere and was visible to our eyes or to sensitive photographic plates loaded at the focus of increasingly large telescopes. With these resources alone, the discoveries were still stupendous: the mapping of our Solar System, the identific ...
The Final Version of the White Paper is available.
... The discovery almost 20 years ago of the first giant planet outside of the solar system (Mayor & Queloz 1995) spawned a real revolution in astronomy. The completely unexpected characteristics of this first planet captured the imagination and interest of the scientific community and the general publi ...
... The discovery almost 20 years ago of the first giant planet outside of the solar system (Mayor & Queloz 1995) spawned a real revolution in astronomy. The completely unexpected characteristics of this first planet captured the imagination and interest of the scientific community and the general publi ...
Collaborations with East Asian VLBI stations
... Target sources : Galactic masers (H2O@22GHz, SiO@43GHz) New aspect: dual-beam for phase-referencing ...
... Target sources : Galactic masers (H2O@22GHz, SiO@43GHz) New aspect: dual-beam for phase-referencing ...
Red supergiants and the past of Cygnus OB2
... main star-forming sites have been shifting with time. The study of this older component is made difficult by the effects of stellar evolution, and in particular by the fact that its most massive components have already disappeared as supernovae. A thus far unexplored probe of the massive star format ...
... main star-forming sites have been shifting with time. The study of this older component is made difficult by the effects of stellar evolution, and in particular by the fact that its most massive components have already disappeared as supernovae. A thus far unexplored probe of the massive star format ...
Searching for the oldest, most metal-poor stars in the SkyMapper Survey
... the universe. Like all stars, the Population III stars performed nuclear fusion in their cores. Hydrogen atoms are fused to form helium, and helium atoms were subsequently fused to form carbon. α-elements, such as magnesium, calcium, and titanium, are made through helium capture by elements such as ...
... the universe. Like all stars, the Population III stars performed nuclear fusion in their cores. Hydrogen atoms are fused to form helium, and helium atoms were subsequently fused to form carbon. α-elements, such as magnesium, calcium, and titanium, are made through helium capture by elements such as ...
Emission from dust in galaxies: Metallicity dependence
... a random-walk process of photons. Next, we define an optical depth of dust grains for Lyα photons over the length of lpath as τdust . It is estimated as τdust ∼ πa2 lpath ndust , where a is the size of grains and ndust is their number density. Here, we will discuss whether the Lyα photons have a cha ...
... a random-walk process of photons. Next, we define an optical depth of dust grains for Lyα photons over the length of lpath as τdust . It is estimated as τdust ∼ πa2 lpath ndust , where a is the size of grains and ndust is their number density. Here, we will discuss whether the Lyα photons have a cha ...
VLT identifications in the Chandra/XMM
... The spectrum in the lower right shows a Seyfert-2 galaxy with heavy X-ray absorption and an AGN-type luminosity. The latter spectrum is characteristic for the bulk of the detected galaxies, which show either no or very faint high excitation lines indicating the AGN nature of the object, so that we h ...
... The spectrum in the lower right shows a Seyfert-2 galaxy with heavy X-ray absorption and an AGN-type luminosity. The latter spectrum is characteristic for the bulk of the detected galaxies, which show either no or very faint high excitation lines indicating the AGN nature of the object, so that we h ...
Galaxies
... • Finding just a few variable stars gives accurate distance measurement as measure apparent luminosity ! distance (absolute brightness plus apparent brightness gives distance) • Early 20th Cent. studies of variable stars in Magellanic ...
... • Finding just a few variable stars gives accurate distance measurement as measure apparent luminosity ! distance (absolute brightness plus apparent brightness gives distance) • Early 20th Cent. studies of variable stars in Magellanic ...
The Evolution of Molecular Clouds
... collisions and coalescence, predicts formation times of at least 100 Myr for giant molecular clouds, and therefore probably cannot be the primary formation mechanism because this is longer than the cloud formation timescale estimated empirically; in any case, most collisions between smaller clouds a ...
... collisions and coalescence, predicts formation times of at least 100 Myr for giant molecular clouds, and therefore probably cannot be the primary formation mechanism because this is longer than the cloud formation timescale estimated empirically; in any case, most collisions between smaller clouds a ...
Chapter 14 Black Holes as Central Engines
... The Planck law describes thermal emission, which is characterized by the emission of radiation from a hot gas that is in approximate thermal equilibrium; the resulting spectrum is a blackbody spectrum. The characteristic Planck law curves for thermal emission peak at some wavelength, and fall off ra ...
... The Planck law describes thermal emission, which is characterized by the emission of radiation from a hot gas that is in approximate thermal equilibrium; the resulting spectrum is a blackbody spectrum. The characteristic Planck law curves for thermal emission peak at some wavelength, and fall off ra ...
Serpens
Serpens (""the Serpent"", Greek Ὄφις) is a constellation of the northern hemisphere. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations defined by the International Astronomical Union. It is unique among the modern constellations in being split into two non-contiguous parts, Serpens Caput (Serpent's Head) to the west and Serpens Cauda (Serpent's Tail) to the east. Between these two halves lies the constellation of Ophiuchus, the ""Serpent-Bearer"". In figurative representations, the body of the serpent is represented as passing behind Ophiuchus between Mu Serpentis in Serpens Caput and Nu Serpentis in Serpens Cauda.The brightest star in Serpens is the red giant star Alpha Serpentis, or Unukalhai, in Serpens Caput, with an apparent magnitude of 2.63. Also located in Serpens Caput are the naked-eye globular cluster Messier 5 and the naked-eye variables R Serpentis and Tau4 Serpentis. Notable extragalactic objects include Seyfert's Sextet, one of the densest galaxy clusters known; Arp 220, the prototypical ultraluminous infrared galaxy; and Hoag's Object, the most famous of the very rare class of galaxies known as ring galaxies.Part of the Milky Way's galactic plane passes through Serpens Cauda, which is therefore rich in galactic deep-sky objects, such as the Eagle Nebula (IC 4703) and its associated star cluster Messier 16. The nebula measures 70 light-years by 50 light-years and contains the Pillars of Creation, three dust clouds that became famous for the image taken by the Hubble Space Telescope. Other striking objects include the Red Square Nebula, one of the few objects in astronomy to take on a square shape; and Westerhout 40, a massive nearby star-forming region consisting of a molecular cloud and an H II region.