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Analysis of Angular Momentum in Planetary Systems and Host Stars
Analysis of Angular Momentum in Planetary Systems and Host Stars

... Quotes ...
The universe of the coming ALMA revolution
The universe of the coming ALMA revolution

The chemical composition of solar-type stars and its impact on the
The chemical composition of solar-type stars and its impact on the

... on the gravitational lensing effect of its host star is measured, and pulsar timing, that lead to the first discovery of an exoplanet in 1992. With the pulsar timing method, observers examine small variations in the extremely periodic radio emission pattern of a star, that are caused by planets. How ...
abstracts book - Instituto de Astrofísica e Ciências do Espaço
abstracts book - Instituto de Astrofísica e Ciências do Espaço

The ALMA Universe - ALMA Observatory
The ALMA Universe - ALMA Observatory

... two things: the color (wavelength) of the light and the diameter of the telescope. ...
IRAM Annual Report 2014
IRAM Annual Report 2014

... asymmetrically distributed in the disk. The authors argue that this is further evidence to support the view that B-type stars may form through diskmediated accretion as their low-mass siblings do, and suggest that the disk structure may be significantly perturbed by tidal interactions with companion ...
Planet Formation in the Outer Solar System
Planet Formation in the Outer Solar System

... the Hayashi (1981) model. The location of this region depends on the disk structure (Sasselov & Lecar 2000). The minimum-mass solar nebula was one of the great successes of early viscous accretion disk theories because steady state disk models often yield S ∝ A⫺3/2. The sharp decrease in the “observ ...
WFC3 Science White Paper - Space Telescope Science Institute
WFC3 Science White Paper - Space Telescope Science Institute

... There are also many key diagnostics of interstellar gas and dust in the region below 4000 Å, including the 2175 Å peak in the dust extinction law, and a number of important emission lines such as the astrophysical plasma diagnostic emission line [O II] 3727 Å. However, neither STIS nor ACS offer goo ...
Untitled - NMSU Astronomy
Untitled - NMSU Astronomy

... this shows the history of the stock market versus time. The “x” (horizontal) axis represents time, and the “y” (vertical) axis represents the value of the stock market. Each place on the curve that shows the performance of the stock market is represented by two numbers, the date (x axis), and the va ...
Multiplicity in Early Stellar Evolution - Astronomy Group
Multiplicity in Early Stellar Evolution - Astronomy Group

A New Measurement of the Fusion Reaction 14N(p,γ)
A New Measurement of the Fusion Reaction 14N(p,γ)

... dominates the low energy cross section. Indirect measurements support our extrapolation of this state to very low energies, which results in a factor of two reduction in the reaction rate for temperature below 108 K. This new result has a significant impact on the theory of the evolution of massive ...
Galaxy Disks Further
Galaxy Disks Further

... they appear to us. Ongoing large surveys, made possible by new instrumentation at wavelengths from the UV (Galaxy Evolution Explorer), via optical (Hubble Space Telescope and large groundbased telescopes) and IR (Spitzer Space Telescope), to the radio are providing much new information about disk ga ...
Tuomas Kangas
Tuomas Kangas

... types is the Hertzsprung-Russell diagram (HRD; Figure 2.1), where stars are placed based on their temperature (i.e. spectral class) and luminosity. Most are clustered on the main sequence, corresponding to the region where a star spends most of its life-time while burning hydrogen. An additional seq ...
Observational Studies of Interacting Galaxies and the Development
Observational Studies of Interacting Galaxies and the Development

... understanding of galaxy merger evolution through both observational studies and instrument developments. Observationally, I approach the goal photometrically and spectroscopically. The photometric studies better constrain the number density evolution of wet and dry mergers through five CFHTLS broad ...
The SMC as a probe of dust in the early Universe
The SMC as a probe of dust in the early Universe

... Dust plays a crucial role in the evolution of a galaxy. Dust directly and indirectly dominates the heating and cooling of clouds and thus regulates star formation. Grain surfaces provide sites for the formation of molecular hydrogen (Hollenbach & Salpeter 1970), another key coolant. The formation of ...
Markov Chain Monte Carlo Modeling of High-Redshift Quasar
Markov Chain Monte Carlo Modeling of High-Redshift Quasar

... Quasars, the visible phenomena associated with the active accretion phase of supermassive black holes found in the centers of galaxies, represent one of the most energetic processes in the Universe. As matter falls into the central black hole, it is accelerated and collisionally heated, and the radi ...
THE STAR FORMATION AND NUCLEAR ACCRETION HISTORIES OF NORMAL GALAXIES
THE STAR FORMATION AND NUCLEAR ACCRETION HISTORIES OF NORMAL GALAXIES

... type over the largely unexplored redshift range 0.1 < ∼z< ∼ 0.5. Because only the closest or brightest of the galaxies are individually detected in X-rays, we use a stacking analysis to determine the mean properties of the sample. Our results suggest that X-ray emission from spectroscopically late-t ...
Evolution of the Milky Way with radial motions of stars and gas
Evolution of the Milky Way with radial motions of stars and gas

... matter and rotational velocity, which also depend on the distribution of the dark matter halo). Some of those properties play an important role in determining the extent of radial displacement of stars; this is the role of the rotation curve for blurring, for example (Sect. 2.2.1). Unfortunately, de ...
A Teacher`s Guide to the Universe
A Teacher`s Guide to the Universe

... the level of structure the bigger the structure gets. In other words, as you build a building out of bricks the building becomes bigger than the bricks. Cities become even bigger than the buildings that make it up. The size of astronomical building blocks is very large and sometimes becomes difficul ...
Jul y 10-12,
Jul y 10-12,

... Almost all Galactic black hole (BH) binaries with low mass donors are transient X-ray sources; we expect most of the X-ray transients (XRTs) observed in external galaxies to be BH binaries also. Obtaining period estimates for extra-galactic XRTs is challenging, but the resulting period distribution ...
act_science_bellringers
act_science_bellringers

... Science Practice Passage ...
preprint, pdf version - LESIA
preprint, pdf version - LESIA

... events observed in Brazil and Chile (4 June 2011) and in Hawaii (23 June 2011). These last two events, as in 22 June 2008, were double events in which Charon and Pluto occulted the same star. In the 4 June 2011 event in particular, both occultations could be recorded at each site. The population of ...
- Isaac Newton Group of Telescopes
- Isaac Newton Group of Telescopes

... cluster’s: 100 million years approximately, with a margin of error below 30%. It was the first time that the age of a celestial object of this nature had been so accurately determined, overcoming one of the most important restrictions preventing the true substellar nature of brown dwarf candidates t ...
Stars and Planets Credits and Acknowledgements
Stars and Planets Credits and Acknowledgements

... galaxies students will move from the 1 to 10 billion scale model used with stars to one showing the size of the Milky Way in comparison to the spacing between galaxies in the Local Group. Images of our galactic neighbors are provided for the teacher to enrich the introduction to galaxies beyond our ...
Studies of molecular clouds at the Galactic centre Roland Karlsson DECLINATION (B1950)
Studies of molecular clouds at the Galactic centre Roland Karlsson DECLINATION (B1950)

... ellipticals (E), spirals (S) with and without bars, and irregulars (Irr). Morphologically, a spiral galaxy comprises a thin disk with spiral arms containing stars, gas and dust and a dense central bulge of stars. In some cases, a transverse central bar (or bars) structure is observed, which is denot ...
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Future of an expanding universe

Observations suggest that the expansion of the universe will continue forever. If so, the universe will cool as it expands, eventually becoming too cold to sustain life. For this reason, this future scenario is popularly called the Big Freeze.If dark energy—represented by the cosmological constant, a constant energy density filling space homogeneously, or scalar fields, such as quintessence or moduli, dynamic quantities whose energy density can vary in time and space—accelerates the expansion of the universe, then the space between clusters of galaxies will grow at an increasing rate. Redshift will stretch ancient, incoming photons (even gamma rays) to undetectably long wavelengths and low energies. Stars are expected to form normally for 1012 to 1014 (1–100 trillion) years, but eventually the supply of gas needed for star formation will be exhausted. And as existing stars run out of fuel and cease to shine, the universe will slowly and inexorably grow darker, one star at a time. According to theories that predict proton decay, the stellar remnants left behind will disappear, leaving behind only black holes, which themselves eventually disappear as they emit Hawking radiation. Ultimately, if the universe reaches a state in which the temperature approaches a uniform value, no further work will be possible, resulting in a final heat death of the universe.
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