sections 19-22 instructor notes
... for a flat rotation curve. As noted by Kerr & Lynden-Bell, many studies of the ratio give values for (σΘ/σΠ)2 very close to 0.5, with typical values ranging from 0.36 to 0.50, and with late-type giants (representing a dynamically relaxed system) giving values of 0.49 to 0.50, closest to the result p ...
... for a flat rotation curve. As noted by Kerr & Lynden-Bell, many studies of the ratio give values for (σΘ/σΠ)2 very close to 0.5, with typical values ranging from 0.36 to 0.50, and with late-type giants (representing a dynamically relaxed system) giving values of 0.49 to 0.50, closest to the result p ...
sections 19-22 instructor notes
... for a flat rotation curve. As noted by Kerr & Lynden-Bell, many studies of the ratio give values for (σΘ/σΠ)2 very close to 0.5, with typical values ranging from 0.36 to 0.50, and with late-type giants (representing a dynamically relaxed system) giving values of 0.49 to 0.50, closest to the result p ...
... for a flat rotation curve. As noted by Kerr & Lynden-Bell, many studies of the ratio give values for (σΘ/σΠ)2 very close to 0.5, with typical values ranging from 0.36 to 0.50, and with late-type giants (representing a dynamically relaxed system) giving values of 0.49 to 0.50, closest to the result p ...
20_Testbank
... 9) Process of Science: Most galaxies do not obey Hubble's Law perfectly. Why do we not take this as evidence that Hubble's law (and the theory of the expanding universe) is incorrect? Answer: Hubble's law describes motions due only to expansion of the universe. In reality we expect (and observe) tha ...
... 9) Process of Science: Most galaxies do not obey Hubble's Law perfectly. Why do we not take this as evidence that Hubble's law (and the theory of the expanding universe) is incorrect? Answer: Hubble's law describes motions due only to expansion of the universe. In reality we expect (and observe) tha ...
Extrasolar Planet Studies:The Italian Contribution
... OmegaTranS will make use of the Omegacam CCD camera on the newly built VLT 2.6m survey Telescope (operational early 2009) ...
... OmegaTranS will make use of the Omegacam CCD camera on the newly built VLT 2.6m survey Telescope (operational early 2009) ...
Title: Binary interaction dominates the evolution of massive stars
... properties of only very few of the young O stars in our sample (see supporting online material §A.2), our derived distributions are a good representation of the binary properties at birth. Thus it is safe to conclude that the most common end product of massive star formation is a rather close binary ...
... properties of only very few of the young O stars in our sample (see supporting online material §A.2), our derived distributions are a good representation of the binary properties at birth. Thus it is safe to conclude that the most common end product of massive star formation is a rather close binary ...
instructor notes: weeks 9/10
... how they differ in terms of the relative frequency of old and young stars, and interstellar gas, within them. 2. Imaging of galaxies and galaxy clusters reveals that it is a “violent” universe. Evidence for collisions between galaxies is everywhere, although keep in mind that by “collisions” we are ...
... how they differ in terms of the relative frequency of old and young stars, and interstellar gas, within them. 2. Imaging of galaxies and galaxy clusters reveals that it is a “violent” universe. Evidence for collisions between galaxies is everywhere, although keep in mind that by “collisions” we are ...
Collisions and Encounters of Stellar Systems
... processes of growing strength. These include steady tidal forces from the host galaxy, and rapidly varying forces as the smaller halo passes through the pericenter of its orbit. As stars are lost from the satellite, they spread out in long, thin tidal streamers that can provide vivid evidence of ong ...
... processes of growing strength. These include steady tidal forces from the host galaxy, and rapidly varying forces as the smaller halo passes through the pericenter of its orbit. As stars are lost from the satellite, they spread out in long, thin tidal streamers that can provide vivid evidence of ong ...
SPIRou Science Case
... searching for biomarkers in their atmospheres is among the main objectives of this new century’s astronomy, motivating ambitious space missions (JWST/NASA, TESS/ NASA, CHEOPS/ESA, PLATO/ESA) The majority of the exoplanets now known were discovered thanks to RV studies measuring Doppler shifts induce ...
... searching for biomarkers in their atmospheres is among the main objectives of this new century’s astronomy, motivating ambitious space missions (JWST/NASA, TESS/ NASA, CHEOPS/ESA, PLATO/ESA) The majority of the exoplanets now known were discovered thanks to RV studies measuring Doppler shifts induce ...
targets - siamois
... Scientific objectives require the observation of a few bright targets for convergence of very precise measurements observed with a small collector ...
... Scientific objectives require the observation of a few bright targets for convergence of very precise measurements observed with a small collector ...
The local spiral structure of the Milky Way
... The idea that the Milky Way is a spiral galaxy was proposed more than one and a half centuries ago (1). However, it was not until the 1950s that some spiral arm segments in the solar neighborhood were clearly identified (2, 3). Since then, many models have been proposed (4) and debated (5). Popular ...
... The idea that the Milky Way is a spiral galaxy was proposed more than one and a half centuries ago (1). However, it was not until the 1950s that some spiral arm segments in the solar neighborhood were clearly identified (2, 3). Since then, many models have been proposed (4) and debated (5). Popular ...
Dynamical properties of a large young disk galaxy at z=2.03⋆
... end of the range found by Trujillo et al. (2006) for all galaxies at similar z in the two FIRES fields. They are bright in K (K= 19.7 − 21.1) and have large stellar masses (M > 1011 M⊙ ). They constitute half of the most rest-frame luminous galaxies (LV > 6 × 1010 h−2 70 L⊙ ) and their number densit ...
... end of the range found by Trujillo et al. (2006) for all galaxies at similar z in the two FIRES fields. They are bright in K (K= 19.7 − 21.1) and have large stellar masses (M > 1011 M⊙ ). They constitute half of the most rest-frame luminous galaxies (LV > 6 × 1010 h−2 70 L⊙ ) and their number densit ...
Module 11.1.1: Galaxies: Morphology and the Hubble Sequence
... universe now, and their masses range from hundreds of million to maybe trillion solar masses, containing up to couple of hundred billion stars. [slide 3] The first thing that any empirical ...
... universe now, and their masses range from hundreds of million to maybe trillion solar masses, containing up to couple of hundred billion stars. [slide 3] The first thing that any empirical ...
SAGE_prop
... Beyond the provision of light and heat, the correlation between the occurrence of sunspots and displays of spectacular aurora gave us early clues to the existence of a chain of events linking solar phenomena to a terrestrial response. Proctor in 1870 described an event where at a station in Norway “ ...
... Beyond the provision of light and heat, the correlation between the occurrence of sunspots and displays of spectacular aurora gave us early clues to the existence of a chain of events linking solar phenomena to a terrestrial response. Proctor in 1870 described an event where at a station in Norway “ ...
Luminosity and Mass Functions of Galaxies
... history (e.g. Dn (4000) or Sérsic index). When galaxies are classified by star-formation history, other parameters (e.g. Dn (4000), Sérsic index, Hubble type, quantitative morphology parameters) are nearly uncorrelated with environment. Significant differences between Nn = 0 and Nn = 1. Degeneracy ...
... history (e.g. Dn (4000) or Sérsic index). When galaxies are classified by star-formation history, other parameters (e.g. Dn (4000), Sérsic index, Hubble type, quantitative morphology parameters) are nearly uncorrelated with environment. Significant differences between Nn = 0 and Nn = 1. Degeneracy ...
PACS Calibration Status and Plans
... • contents - calibration accuracy of individual AOT modes with regard to point and extended sources - dynamic range, image quality - consistency check with other AOT modes - check of internal calibration scheme (robustness against drifts) - check of pointing, raster map and scan map mode parameter s ...
... • contents - calibration accuracy of individual AOT modes with regard to point and extended sources - dynamic range, image quality - consistency check with other AOT modes - check of internal calibration scheme (robustness against drifts) - check of pointing, raster map and scan map mode parameter s ...
Galaxy Evolution
... and that it is generating new stars at a rate of, say, 10 solar masses per year or M yr−1 (this is the total stellar mass, not the number, of new stars). The STELLAR MASSES of freshly produced stars are not all equal, but vary approximately between 100 solar masses to about one tenth of solar mass ...
... and that it is generating new stars at a rate of, say, 10 solar masses per year or M yr−1 (this is the total stellar mass, not the number, of new stars). The STELLAR MASSES of freshly produced stars are not all equal, but vary approximately between 100 solar masses to about one tenth of solar mass ...
Galaxy Evolution Encyclopedia of Astronomy & Astrophysics eaa.iop.org Mauro Giavalisco
... and that it is generating new stars at a rate of, say, 10 solar masses per year or M yr−1 (this is the total stellar mass, not the number, of new stars). The STELLAR MASSES of freshly produced stars are not all equal, but vary approximately between 100 solar masses to about one tenth of solar mass ...
... and that it is generating new stars at a rate of, say, 10 solar masses per year or M yr−1 (this is the total stellar mass, not the number, of new stars). The STELLAR MASSES of freshly produced stars are not all equal, but vary approximately between 100 solar masses to about one tenth of solar mass ...
Evidence for the Tidal Destruction of Hot Jupiters by Subgiant Stars
... Tidal transfer of angular momentum is expected to cause hot Jupiters to spiral into their host stars. Although the timescale for orbital decay is very uncertain, it should be faster for systems with larger and more evolved stars. Indeed, it is well established that hot Jupiters are found less freque ...
... Tidal transfer of angular momentum is expected to cause hot Jupiters to spiral into their host stars. Although the timescale for orbital decay is very uncertain, it should be faster for systems with larger and more evolved stars. Indeed, it is well established that hot Jupiters are found less freque ...
lecture course
... gravitational lensing (both weak and strong) measurements. The existence of dark matter in a cosmological context comes from the consideration of a large number of datasets in conjunction with each other.for example, information comes from measurements of cosmic shear and the Lyman forest. Cosmologi ...
... gravitational lensing (both weak and strong) measurements. The existence of dark matter in a cosmological context comes from the consideration of a large number of datasets in conjunction with each other.for example, information comes from measurements of cosmic shear and the Lyman forest. Cosmologi ...
An Expanded View of the Universe
... companions with masses ranging from a few Earth to several Jupiter masses have been found. Most exoplanets are detected indirectly by the radial velocity technique, a method that detects planets by the “wobble” they produce on their parent star as they orbit it. However, such indirect detections onl ...
... companions with masses ranging from a few Earth to several Jupiter masses have been found. Most exoplanets are detected indirectly by the radial velocity technique, a method that detects planets by the “wobble” they produce on their parent star as they orbit it. However, such indirect detections onl ...
Superstars of Astronomy: Debra Fischer transcript
... astronomers heard about this. This is a neutron star, a star that has probably gone supernova, exploded, and then just a tiny little remnant of a core of the former star is left behind, and Alex Wolszczan at Penn State is able to measure the timing from the pulsar and figure out that there were thre ...
... astronomers heard about this. This is a neutron star, a star that has probably gone supernova, exploded, and then just a tiny little remnant of a core of the former star is left behind, and Alex Wolszczan at Penn State is able to measure the timing from the pulsar and figure out that there were thre ...
Quantitative constraints on starburst cycles in galaxies with stellar
... The models in Figure 1 include many objects with underlying old stellar populations that are currently undergoing a burst. These appear at high values of SFR/M∗ and high/low values of Dn (4000)/HδA . However, galaxies of this type do not appear to be present in the real data. We comment briefly on t ...
... The models in Figure 1 include many objects with underlying old stellar populations that are currently undergoing a burst. These appear at high values of SFR/M∗ and high/low values of Dn (4000)/HδA . However, galaxies of this type do not appear to be present in the real data. We comment briefly on t ...
25 Years of the Hubble Space Telescope - Speaker
... Note that 1946 is before the start of the space age. Even before they had the capacity to build them, astronomers were dreaming of space telescopes. This image of Lyman Spitzer was taken decades later at Princeton University. In July, 1958, the National Aeronautics and Space Administration (NASA) wa ...
... Note that 1946 is before the start of the space age. Even before they had the capacity to build them, astronomers were dreaming of space telescopes. This image of Lyman Spitzer was taken decades later at Princeton University. In July, 1958, the National Aeronautics and Space Administration (NASA) wa ...
Stellar Intensity Interferometry: The Background John Davis Sydney Institute for Astronomy
... outputs before and after each night of observations • The scale of the correlation depends on instrumental parameters and the scale changes if, for example, the detectors are changed • Hence it is necessary to measure both short and long baselines with the same instrument parameters – also identif ...
... outputs before and after each night of observations • The scale of the correlation depends on instrumental parameters and the scale changes if, for example, the detectors are changed • Hence it is necessary to measure both short and long baselines with the same instrument parameters – also identif ...
Lab 14 Galaxy Morphology
... the center. These black holes can have a mass that is a billion times that of the Sun (109 M! )! But not all galaxies have these ferocious beasts at their cores, some merely have large clusters of young stars, while others have a nucleus that is dominated by large numbers of old stars. The Sun orbit ...
... the center. These black holes can have a mass that is a billion times that of the Sun (109 M! )! But not all galaxies have these ferocious beasts at their cores, some merely have large clusters of young stars, while others have a nucleus that is dominated by large numbers of old stars. The Sun orbit ...
Space Interferometry Mission
The Space Interferometry Mission, or SIM, also known as SIM Lite (formerly known as SIM PlanetQuest), was a planned space telescope developed by the U.S. National Aeronautics and Space Administration (NASA), in conjunction with contractor Northrop Grumman. One of the main goals of the mission was the hunt for Earth-sized planets orbiting in the habitable zones of nearby stars other than the Sun. SIM was postponed several times and finally cancelled in 2010.In addition to hunting for extrasolar planets, SIM would have helped astronomers construct a map of the Milky Way galaxy. Other important tasks would have included collecting data to help pinpoint stellar masses for specific types of stars, assisting in the determination of the spatial distribution of dark matter in the Milky Way and in the Local Group of galaxies and using the gravitational microlensing effect to measure the mass of stars.The spacecraft would have used optical interferometry to accomplish these and other scientific goals. This technique collects light with multiple mirrors (in SIM's case, two) which is combined to make an interference pattern which can be very precisely measured.The initial contracts for SIM Lite were awarded in 1998, totaling US$200 million. Work on the SIM project required scientists and engineers to move through eight specific new technology milestones, and by November 2006, all eight had been completed.SIM Lite was originally scheduled for a 2005 launch, aboard an Evolved Expendable Launch Vehicle (EELV). As a result of continued budget cuts, the launch date has been pushed back at least five times. NASA has set a preliminary launch date for 2015 and U.S. federal budget documents confirm that a launch date is expected ""no earlier"" than 2015. The budget cuts to SIM Lite are expected to continue through FY 2010. As of February 2007, many of the engineers working on the SIM program had moved on to other areas and projects, and NASA directed the project to allocate its resources toward engineering risk reduction. However, the preliminary budget for NASA for 2008 included zero dollars for SIM.In December 2007, the Congress restored funding for fiscal year 2008 as part of an omnibus appropriations bill which the President later signed. At the same time the Congress directed NASA to move the mission forward to the development phase. In 2009 the project continued its risk reduction work while waiting for the findings and recommendations of the Astronomy and Astrophysics Decadal Survey, Astro2010, performed by the National Academy of Sciences, which would determine the project's future.On 13 August 2010, the Astro2010 Decadal Report was released and did not recommend that NASA continue the development of the SIM Lite Astrometric Observatory. This prompted NASA Astronomy and Physics Director, Jon Morse, to issue a letter on 24 September 2010 to the SIM Lite project manager, informing him that NASA was discontinuing its sponsorship of the SIM Lite mission and directing the project to discontinue Phase B activities immediately or as soon as practical. Accordingly, all SIM Lite activities were closed down by the end of calendar year 2010.