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History of astronomy
History of astronomy

Death of High Mass Stars
Death of High Mass Stars

... what point the stars leave the main sequence; the ...
20040907103511001-148699
20040907103511001-148699

...  Rotation period has increased by factor of 10 during life  Viscosity too small to reduce rotation homogeneously throughout the Sun  Magnetic Ap stars rotate much slower than „normal“ A stars  Did MRI reduce the internal rotation of Sun and Ap stars? ...
The Hubble Space Telescope - the first 10 years
The Hubble Space Telescope - the first 10 years

Beyond Our Solar System
Beyond Our Solar System

... In this figure, your field of view widens by a factor of 100, and you can see an area 1 mile in diameter. – The arrow points to the scene shown in the preceding photo. – People, trees, and sidewalks have vanished, but now you can see a college campus and the surrounding streets and houses. – The di ...
PPT - Chinese Virtual Observatory
PPT - Chinese Virtual Observatory

... software tools that will also be useful for the development of China's Virtual Observatory(VO). The LAMOST data set, including all its subcatalogues and FITs files of 1-d spectra, will of course be another important contribution to the ...
Groups of Stars
Groups of Stars

May / June 2009 - Astroadventures.net
May / June 2009 - Astroadventures.net

... Filling the gaps between planets and bright, deep-sky objects are an abundance of double stars. Accompanied by a little context, these targets provide a myriad of opportunities to share astronomy with any audience. To that end, I am submitting a short list of easily located and resolved double stars ...
Week 6
Week 6

... If Betelgeuse is 640 ly from Earth, what is the brightness of the light from Betelgeuse that reaches Earth? ...
Powerpoint of lecture 14
Powerpoint of lecture 14

... • Post-MS timescale also nuclear (except for a few phases) – so again much more data than for pre-MS studies • Two kinds of observational constraint  Statistical studies of large numbers of field stars (problem: selection effects, e.g. more luminous stars dominate sample)  Look at star clusters: s ...
The Stellar Content of Obscured Galactic Giant H II Regions
The Stellar Content of Obscured Galactic Giant H II Regions

... infrared spectroscopy. It has been revealed that the stellar cluster in the central parsec, as well as two other nearby clusters, are rich in OB and Wolf–Rayet stars (see Morris & Serabyn 1996 for a recent review and the many references therein). Massey et al. (1995) have produced a detailed charact ...
Stars - Mike Brotherton
Stars - Mike Brotherton

... Same phenomenon makes the day sky appear blue (if it’s not cloudy). ...
Observations and Theoretical Models of Subdwarfs
Observations and Theoretical Models of Subdwarfs

... be a member of a binary system. While a disproportionate number of these stars are binaries -- quoted figures from a variety of sources range from at least half to just short of 100% depending on the method of detection used -- it cannot be safely assumed that all of them are. A second model by whic ...
Weather in stellar atmosphere: The dynamics of mercury clouds in α
Weather in stellar atmosphere: The dynamics of mercury clouds in α

... in the heavy12 and iron-peak17 element abundances is often reported for stars with similar funda3 ...
Stars: from Adolescence to Old Age
Stars: from Adolescence to Old Age

... swallow Mercury,Venus and perhaps the Earth too. – Or conditions on Earth’s surface will become impossible for life to exist. – Water oceans and atmosphere will evaporate away. ...
Pre-Workshop Thought Questions 1. List several ways you think
Pre-Workshop Thought Questions 1. List several ways you think

... Galileo was a strong supporter of the Copernican model for the Solar System, and with Kepler’s work on the laws of planetary motion being published around the same time, the relative scale of the Solar System was well known (the absolute scale needed an accurate determination of the AU, which wouldn ...
PHYSICS 1500 - ASTRONOMY TOTAL: 100 marks Section A Please
PHYSICS 1500 - ASTRONOMY TOTAL: 100 marks Section A Please

... highlands. The planets of the solar system formed in an accretion disk around the infant Sun. Nuclear reaction rates inside stars increase rapidly with temperature. Stars lose significant amounts of mass during their lifetime. ...
Presentation
Presentation

... • Dense regions in molecular clouds (>one million particles per cm3) • If the cloud is big enough, it will undergo gravitational collapse ...
Chapter 20 Stellar Evolution (20.1-20.3)
Chapter 20 Stellar Evolution (20.1-20.3)

Review Astronomy - Cowley`s Earth Systems
Review Astronomy - Cowley`s Earth Systems

... studying red shifts of galaxies, he proposed that the universe began with an immense infusion of pure energy into space. Later, Edwin Hubble discovered that the speed of a galaxy moving away from Earth was proportional to its distance. This relation was predicted by Lemaitre’s theory. Then, in 1964, ...
Universe 8e Lecture Chapter 17 Nature of Stars
Universe 8e Lecture Chapter 17 Nature of Stars

... theory of stellar evolution describes how stars form and change during that life span. Mass Loss by Protostars: In the final stages of pre– main-sequence contraction, when thermonuclear reactions are about to begin in its core, a protostar may eject large amounts of gas into space. Low-mass stars th ...
Universe 8e Lecture Chapter 17 Nature of Stars
Universe 8e Lecture Chapter 17 Nature of Stars

... theory of stellar evolution describes how stars form and change during that life span. Mass Loss by Protostars: In the final stages of pre– main-sequence contraction, when thermonuclear reactions are about to begin in its core, a protostar may eject large amounts of gas into space. Low-mass stars th ...
PowerPoint
PowerPoint

... a) a tennis ball here, and one on the Moon. b) two beach balls separated by 100 city blocks. c) two grains of sand 100 light- years apart. d) two golf balls 100 km apart. e) two baseballs 100 yards apart. ...
Stellar Life Stages
Stellar Life Stages

... use up their hydrogen and collapse into a white dwarf ...
–1– 2. Milky Way We know a great deal, perhaps more than any
–1– 2. Milky Way We know a great deal, perhaps more than any

... is about 27 pc above the Galactic plane. Furthermore, the vertical distribution of stars in the solar neighborhood can be approximated by the sum of two exponentials. These were identified as a thin disk and a thick disk components. The stars in the thin and thick disks appear to have different ages ...
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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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