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The local spiral structure of the Milky Way
The local spiral structure of the Milky Way

Section9 - University of Chicago
Section9 - University of Chicago

... The first piece of direct evidence for a change in galaxy populations came in the 1980s from observations of something now known as the Butcher-Oemler effect. Basically this is the observation that distant clusters of galaxies have proportionately more blue (actively star ...
arXiv:1404.0641v2 [astro
arXiv:1404.0641v2 [astro

... planets in the Milky Way that are able to develop and sustain life, and how such an ability depends on particular physical and chemical conditions on the planet. The latter is of a primary importance for developing the future strategy of looking for life on habitable planets. For example, in the lis ...
High-precision abundances of elements in solar twin stars: Trends
High-precision abundances of elements in solar twin stars: Trends

... spectra are available based on reflected light from asteroids and the Jupiter moon Ganymede. As the prime reference spectrum for the Sun, the Vesta spectrum with S /N ≃ 1200 is adopted, but it is noted that the Ceres and Ganymede spectra agree very well with that of Vesta. Equivalent widths measured ...
Word version of Episode 704
Word version of Episode 704

... The Andromeda galaxy M31 can just, but only just, be seen with the naked eye. Its light, 2 million years old, is the oldest light you can see with the unaided eye. The Andromeda galaxy, M31, is the nearest neighbour large galaxy to our own Galaxy, the Milky Way. It is about 2.2 million light years a ...
Adult education at Scienceworks
Adult education at Scienceworks

... 2 Mark and label the equator half way around your spherical object as best as you can either using a texta or sticking a piece of string horizontally around the diameter. 3 Add lines of latitude 30 degrees S, 30 degrees N, 60 degrees S and 60 degrees N. (The lines of latitude are measured from the e ...
ppt
ppt

Absolute magnitude of type Ia supernovae
Absolute magnitude of type Ia supernovae

... last stage of a star’s evolution. Since its brightness temporarily reach to a few hundreds million times of our sun’s, we can find it from fairly far distance. It rarely occurs once in a hundred years at a galaxy, but there are many galaxies in the Universe, therefore by observing everywhere, a supe ...
Dynamical Mass Measurements of Pre-Main
Dynamical Mass Measurements of Pre-Main

... radial velocities of the primary stars relative to their secondaries (e.g., Rucinski, 1999). These effects can be minimized by selecting templates that are well matched to the target stars in spectral type, by avoiding orbital phases subject to strong line blending, and by employing techniques desig ...
milano2006_popov - X-Ray
milano2006_popov - X-Ray

INTERSTELLAR MedLab
INTERSTELLAR MedLab

... 7. Complete the table below assuming the star counts out through magnitude 10 represent a section of the sky where interstellar absorption is non-existent. ...
Finding the Most Distant Quasars Using Bayesian Selection Methods
Finding the Most Distant Quasars Using Bayesian Selection Methods

15_Testbank
15_Testbank

... 15) Why is the spectral sequence of stars not alphabetical? A) The letters refer to the initials of the original discovers. B) The original alphabetical labeling did not correspond to surface temperature and thus had to be reordered. C) They were chosen to fit a mnemonic. D) Because there is still ...
Set 2: Nature of Galaxies
Set 2: Nature of Galaxies

Numerical simulations of convection in A
Numerical simulations of convection in A

... other quantities. E. g., the density change is reflected in the velocity and is prominent in all gradient–like quantities like the velocity. The movie of the pressure fluctuations show the change of log(pressure) in time, scaled by a power of the temperature to enhance the tiny fluctuations in deepe ...
Parallax - Georgia State University
Parallax - Georgia State University

... • Stars (five to fifteen) are identified around the target object. • Their positions are used to denote a reference frame General Definition Types of Parallax The ideal case How stars move How the Earth moves Atmospheric effects Telescope effects Van de Kamp Observations The Reference Field Absolut ...
First Light for May, 2001 - South Bay Astronomical Society
First Light for May, 2001 - South Bay Astronomical Society

June 2010 - Denver Astronomical Society
June 2010 - Denver Astronomical Society

... Digital imagery has revealed the staggering sensitivity of the silicon CCD chip, particularly in applications to astronomy. The “Antennae,” NGCs 4038 and 39 in Corvus the Crow, are targets that challenged film photographers not long ago, keeping their details secret. No more. This beautiful negative ...
Chapter 12: Stars and Galaxies
Chapter 12: Stars and Galaxies

... A spectroscope is an instrument that can be used to study the light that comes from stars. Figure 3 shows the different parts of a spectroscope. Spectroscopes often contain elements, such as slits, prisms, diffraction gratings, and lenses to distribute and focus light. Using spectroscopes, astronome ...
File
File

... Scientists have studied stars to discover how stars evolve. They know that stars form in a nebula when clouds of dust and gas are pulled together by gravity. Describe how this process continues for stars much more massive than the Sun. ...
Chapter 15
Chapter 15

... • Early in the history of the universe, hydrogen and helium (and other forms of matter) clumped together by gravitational attraction to form countless trillions of stars. Billions of galaxies, each a cluster of billions of stars, now form most of the visible mass in the universe. ...
document
document

... reduce up and down motions. ...
ch19
ch19

... Early attempts to locate our solar system produced erroneous results. The main problem was that interstellar extinction allows one to only see the nearby stars and makes distant objects appear dimmer. The key to finding our location in the galaxy is locating bright objects out of the plane of the ga ...
Wolf-Rayet Stars
Wolf-Rayet Stars

... of material lost per year) are extreme, typically in excess of 10−5 M yr−1 . These mass-loss rates are sufficient to affect the evolution of the star, and must be incorporated into stellar evolutionary calculations. The (average) maximum velocity of material in W-R winds (called the terminal velocity, ...
What makes stars tick?
What makes stars tick?

... tens of thousands of burning orbs of gas. Just one of those twinkling dots we call stars could be a behemoth with a mass 80 times that of our own Sun. At it’s core sits a cauldron of nuclear reactions that power the star, allowing us to see it glowing from hundreds of light-years away. What could ho ...
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Hipparcos



Hipparcos was a scientific satellite of the European Space Agency (ESA), launched in 1989 and operated until 1993. It was the first space experiment devoted to precision astrometry, the accurate measurement of the positions of celestial objects on the sky. This permitted the accurate determination of proper motions and parallaxes of stars, allowing a determination of their distance and tangential velocity. When combined with radial-velocity measurements from spectroscopy, this pinpointed all six quantities needed to determine the motion of stars. The resulting Hipparcos Catalogue, a high-precision catalogue of more than 118,200 stars, was published in 1997. The lower-precision Tycho Catalogue of more than a million stars was published at the same time, while the enhanced Tycho-2 Catalogue of 2.5 million stars was published in 2000. Hipparcos‍ '​ follow-up mission, Gaia, was launched in 2013.The word ""Hipparcos"" is an acronym for High precision parallax collecting satellite and also a reference to the ancient Greek astronomer Hipparchus of Nicaea, who is noted for applications of trigonometry to astronomy and his discovery of the precession of the equinoxes.
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