Star formation rates from young-star counts and the structure of the
... Evans et al. (2009) and Lada et al. (2010) present the total SFRs based on young stellar object (YSO) candidates, identified from their mid-IR excess using Spitzer and compare those to molecular cloud masses derived using extinction maps for ∼10 nearby molecular clouds. These studies show that there ...
... Evans et al. (2009) and Lada et al. (2010) present the total SFRs based on young stellar object (YSO) candidates, identified from their mid-IR excess using Spitzer and compare those to molecular cloud masses derived using extinction maps for ∼10 nearby molecular clouds. These studies show that there ...
POSTERS SESSION I: Atmospheres of Massive Stars
... Massive stars have strong stellar winds that exhibit variability on timescales ranging from hours to years. Many classes of these stars are also seen, via photometric or line-profile variability, to pulsate radially or nonradially. It has been suspected for some time that these oscillations can indu ...
... Massive stars have strong stellar winds that exhibit variability on timescales ranging from hours to years. Many classes of these stars are also seen, via photometric or line-profile variability, to pulsate radially or nonradially. It has been suspected for some time that these oscillations can indu ...
Annual report 2004 - Département d`Astrophysique, Géophysique et
... period of 357.0 days. We derive for the first time the orbital parameters of the system and find a very eccentric orbit (e=0.81) and similar component masses with a mass ratio M1/M2=1.02. Cen forms a challenge for current evolution scenarios in close binaries and it is also a puzzle how a massive bi ...
... period of 357.0 days. We derive for the first time the orbital parameters of the system and find a very eccentric orbit (e=0.81) and similar component masses with a mass ratio M1/M2=1.02. Cen forms a challenge for current evolution scenarios in close binaries and it is also a puzzle how a massive bi ...
Reflecting telescopes - School
... right) stars. Stars leave this main sequence when the dominant fusion progress changes; when this occurs they will become one of the following stars: Red Giants and Supergiants are relatively cool and therefore emit a small amount of light per unit surface area. This means that to be as bright as th ...
... right) stars. Stars leave this main sequence when the dominant fusion progress changes; when this occurs they will become one of the following stars: Red Giants and Supergiants are relatively cool and therefore emit a small amount of light per unit surface area. This means that to be as bright as th ...
Line-profile tomography of exoplanet transits – II. A gas
... transits have previously been reported in the lightcurve obtained by the SuperWASP survey of the A5 star HD15082 (WASP-33; V = 8.3, v sin i = 86 km s−1 ). Here we report further photometry and time-series spectroscopy through three separate transits, which we use to confirm the existence of a gas gi ...
... transits have previously been reported in the lightcurve obtained by the SuperWASP survey of the A5 star HD15082 (WASP-33; V = 8.3, v sin i = 86 km s−1 ). Here we report further photometry and time-series spectroscopy through three separate transits, which we use to confirm the existence of a gas gi ...
Through Hubble`s Eye - Arizona State University
... after 14 straight days of focused HST observation, the scientists produced the Hubble Deep Field image. The image was filled with irregular galaxies, showing just how common they were in the universe. Windhorst and his colleagues realized that things probably weren’t exactly as they seemed. Very lit ...
... after 14 straight days of focused HST observation, the scientists produced the Hubble Deep Field image. The image was filled with irregular galaxies, showing just how common they were in the universe. Windhorst and his colleagues realized that things probably weren’t exactly as they seemed. Very lit ...
Chap4-Timing
... Fate of planetary systems during the red giant phase. All planets within the final extent of the red giant envelope will be engulfed and migrate inwards. Planets further out will have greater chance of survival, migrating outwards as mass is lost from central star. In mass is loss instantane ...
... Fate of planetary systems during the red giant phase. All planets within the final extent of the red giant envelope will be engulfed and migrate inwards. Planets further out will have greater chance of survival, migrating outwards as mass is lost from central star. In mass is loss instantane ...
Title: Binary interaction dominates the evolution of massive stars
... are expressed in terms of the fraction of all stars born as O-type stars, including the single O stars and the O stars in binaries, either as the initially more massive component (the primary), or the less massive one (the secondary). The solid curve gives the best-fit intrinsic distribution of orbi ...
... are expressed in terms of the fraction of all stars born as O-type stars, including the single O stars and the O stars in binaries, either as the initially more massive component (the primary), or the less massive one (the secondary). The solid curve gives the best-fit intrinsic distribution of orbi ...
Document
... • In 100 years, M27 has expanded 2” • Today it is 5’=300” in size • How old is it? • (300”)(100 yr/2”)= 15,000 years ...
... • In 100 years, M27 has expanded 2” • Today it is 5’=300” in size • How old is it? • (300”)(100 yr/2”)= 15,000 years ...
Chapter 2 Observing the Electromagnetic Spectrum
... The High Energy Astrophysical Observatory-2 (HEAO-2), later named Einstein, was launched into low Earth orbit on November 13th, 1978 and operated until April, 1981. It was the first X-ray mission to use focusing optics with imaging detectors and produce angular resolution of a few arc seconds3 ( ′′ ...
... The High Energy Astrophysical Observatory-2 (HEAO-2), later named Einstein, was launched into low Earth orbit on November 13th, 1978 and operated until April, 1981. It was the first X-ray mission to use focusing optics with imaging detectors and produce angular resolution of a few arc seconds3 ( ′′ ...
Cosmology with objects from the Hamburg Quasar Surveys
... high-resolution spectra, e.g. with COS on HST, will allow to reconstruct the shape of the metagalactic radiation field, which governs the photoionization of metals in the IGM, from line strength ratios OII/OIII/OIV/OV, NeII/NeIII/NeIV/NeV etc. with high accuracy. For methods and first results cf. A ...
... high-resolution spectra, e.g. with COS on HST, will allow to reconstruct the shape of the metagalactic radiation field, which governs the photoionization of metals in the IGM, from line strength ratios OII/OIII/OIV/OV, NeII/NeIII/NeIV/NeV etc. with high accuracy. For methods and first results cf. A ...
VLA HI Zeeman Observations of the Cygnus X Region: Abstract
... The Very Large Array in Socorro, New Mexico has been used to study the Zeeman Effect in the 21cm HI line seen in absorption against radio sources in the Cygnus X region. Cygnus X is geometrically favorable for Zeeman effect observations as the region lies along the mean field direction of the diffus ...
... The Very Large Array in Socorro, New Mexico has been used to study the Zeeman Effect in the 21cm HI line seen in absorption against radio sources in the Cygnus X region. Cygnus X is geometrically favorable for Zeeman effect observations as the region lies along the mean field direction of the diffus ...
Broadening of spectral lines An individual atom/molecule making a
... lines. However, normally very small - other effects dominate.! e.g. for hydrogen n=2 to n=1 transition (Lyman α transition,! ν= 2.5 1015 Hz) the lifetime is of the order of 10-9 s.! Natural linewidth is ~108 Hz.! ...
... lines. However, normally very small - other effects dominate.! e.g. for hydrogen n=2 to n=1 transition (Lyman α transition,! ν= 2.5 1015 Hz) the lifetime is of the order of 10-9 s.! Natural linewidth is ~108 Hz.! ...
3 sr -1
... The magnitude scale system can be extended towards negative numbers (very bright) and numbers > 6 (faint objects): Sirius (brightest star in the sky): mv = -1.42 Full moon: mv = -12.5 Sun: mv = -26.5 ...
... The magnitude scale system can be extended towards negative numbers (very bright) and numbers > 6 (faint objects): Sirius (brightest star in the sky): mv = -1.42 Full moon: mv = -12.5 Sun: mv = -26.5 ...
Interstellar Space Not as Empty as you Might Think
... Interstellar clouds are the start and end points of a star’s life. Dying stars release heavy elements back into interstellar space, which becomes richer and richer in heavy elements over time (its metallicity goes up) ...
... Interstellar clouds are the start and end points of a star’s life. Dying stars release heavy elements back into interstellar space, which becomes richer and richer in heavy elements over time (its metallicity goes up) ...
Interstellar Space
... Interstellar clouds are the start and end points of a star’s life. Dying stars release heavy elements back into interstellar space, which becomes richer and richer in heavy elements over time (its metallicity goes up) All the heavy elements in the Earth were made in stars, then spent time in interst ...
... Interstellar clouds are the start and end points of a star’s life. Dying stars release heavy elements back into interstellar space, which becomes richer and richer in heavy elements over time (its metallicity goes up) All the heavy elements in the Earth were made in stars, then spent time in interst ...
5 Report of the Panel on Stars and Stellar Evolution
... Report of the Panel on Stars and Stellar Evolution SUMMARY The science frontier for stars and stellar evolution is as close as the Sun and as distant as exploding stars at redshift 8.3. It includes understanding processes of exquisite complexity that connect the rotation of stars with their magnetic ...
... Report of the Panel on Stars and Stellar Evolution SUMMARY The science frontier for stars and stellar evolution is as close as the Sun and as distant as exploding stars at redshift 8.3. It includes understanding processes of exquisite complexity that connect the rotation of stars with their magnetic ...
Interstellar Space Not as Empty as you Might Think
... Interstellar clouds are the start and end points of a star’s life. Dying stars release heavy elements back into interstellar space, which becomes richer and richer in heavy elements over time (its metallicity goes up) All the heavy elements in the Earth were made in stars, then spent time in interst ...
... Interstellar clouds are the start and end points of a star’s life. Dying stars release heavy elements back into interstellar space, which becomes richer and richer in heavy elements over time (its metallicity goes up) All the heavy elements in the Earth were made in stars, then spent time in interst ...
Star formation
Star formation is the process by which dense regions within molecular clouds in interstellar space, sometimes referred to as ""stellar nurseries"" or ""star-forming regions"", collapse to form stars. As a branch of astronomy, star formation includes the study of the interstellar medium (ISM) and giant molecular clouds (GMC) as precursors to the star formation process, and the study of protostars and young stellar objects as its immediate products. It is closely related to planet formation, another branch of astronomy. Star formation theory, as well as accounting for the formation of a single star, must also account for the statistics of binary stars and the initial mass function.In June 2015, astronomers reported evidence for Population III stars in the Cosmos Redshift 7 galaxy at z = 6.60. Such stars are likely to have existed in the very early universe (i.e., at high redshift), and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life as we know it.