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Classifying the Stars
Classifying the Stars

... Name:_______________________________ ...
Lecture 22 - Cosmic distance scale
Lecture 22 - Cosmic distance scale

... As the Earth moves from one side of the Sun to the other, a nearby star will seem to change its position relative to the distant background stars. ...
NGC 3801 caught in the act: A post-merger starforming early
NGC 3801 caught in the act: A post-merger starforming early

... more similar to the hysteresis loop. The radio lobes, also in the shape of S, is seen confined within this hysteresis loop structure (HLS), with similar clockwise bending (See Fig.1; Heckman et al. 1986). Surrounding these radio lobes, shock shells have been discovered with the Chandra X-ray observa ...
What we can measure
What we can measure

... that a star is “wobbling” as if it is swinging another heavy object around it – even if the heavy object can’t be seen. This can occur if the star is swinging a “dark” star or perhaps a “burned out” star. These are called “astrometric binaries”. This will have to be considered when looking at the bi ...
Stars - gilbertmath.com
Stars - gilbertmath.com

... 3. With ________ gravity and __________ pressures than other stars, the  ______________ reactions in the core happen at a relatively ________ rate 4. Shine ____________ as small red stars called ______  ____________ 5. The light of a ______  ____________ stars dim and gradually grows ____________ 6. ...
Luminosity
Luminosity

... These two stars have about the same luminosity -- which one appears brighter? A. Alpha Centauri B. The Sun ...
Ursa Major, the Great Bear
Ursa Major, the Great Bear

... spiral arms surrounding a bright central mass of stars. M81 sometimes is called the Bode's Galaxy because it was originally discovered by Johann Elert Bode, in 1774.  M81 can be found by extending the imaginary line from γ Ursae Majoris to α Ursae Majoris about the same distance northwestward. M81 ...
The driving mechanism of starbursts in galaxy mergers
The driving mechanism of starbursts in galaxy mergers

... models, where the multiphase ISM is not resolved and is modeled as a relatively homogeneous and stable medium. While merger-driven bursts of star formation are generally attributed to large-scale gas inflows towards the nuclear regions, we show that once a realistic ISM is resolved, the dominant pro ...
Science Olympiad 2008 Reach for the Stars Division B
Science Olympiad 2008 Reach for the Stars Division B

... 117. Rank these 4 clusters by age, from youngest to oldest A) ABCD B) DCBA C) DBAC D) CBAD E) BACD 118. (True/False) In any star cluster, stars with lower masses greatly outnumber those with higher masses. 119. (True/False) Stars with higher masses live longer than stars with lower masses. 120. (Tru ...
flare swg usa
flare swg usa

... Fitting SEDS: The long-λ fluxes from cool dust have ambiguous SED fits, while higher spatial resolution, near-IR fluxes from clustered sources are often very much fainter. FLARE can reach ~8 mag deeper than IRAC surveys at 3.5 μm, enabling the measurement of the NIR SEDs of young (<104 yr old) ...
Big Bear Valley Astronomical Society
Big Bear Valley Astronomical Society

... connected to Sirius as the constellation itself did not take on its current form until Roman times. Sirius is a hot white star that will shine brightly for a long time to come. It is also a known binary system, with a tiny white dwarf star, coloquially known as 'the Pup', circling the brighter prima ...
The mid- and far-infrared range - International Space Science Institute
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... and neutral molecules and dust attain temperatures in the range of about 5 K to 1000 K and therefore emit most of their energy at mid- and far-IR wavelengths. Generally, the near-IR range is defined as extending from 0.75 µm to 2.5 µm and the mid-IR range runs from 2.5 µm to about 25 µm. The far-IR ...
File - We All Love Science
File - We All Love Science

... What are the general properties of White Dwarfs? • After ejection of planetary nebula shell, the core is what’s left. That’s our white dwarf • Mainly C and O2, trace H and He on crust • Cools rapidly (by universal standards) • Eventually dies out, like an ember in a fire • Becomes so dark referred ...
Radiation: The Key to Understanding the Universe
Radiation: The Key to Understanding the Universe

... the place of nuclear energy generation. The temperature decreases outwards and the energy generated at the centre in the form of γ rays flows outwards, continuously getting absorbed and reemitted. The radiation that we receive from the stars is emitted from what is called the photosphere beyond (outw ...
Chapter21
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... 1. The Kinds of Binary Stars In most other introductory astronomy textbooks, binary stars are covered in a piecemeal fashion in several different chapters. There are several reasons why I decided to cover binary stars in a single coherent chapter. First, most stars are in binary or multiple systems, ...
Kepler-452b is not a new Earth A twin of the Sun
Kepler-452b is not a new Earth A twin of the Sun

... Around Pluto instrument have instead shown that Pluto's atmosphere is constantly being stripped of gas by the solar wind action, that with its pressure forms behind the planet a tail extending over 100,000 km. The fact that despite this phenomenon Pluto still has an atmosphere means that the gas mak ...
Self-Regulation of Star Formation in Low Metallicity Clouds
Self-Regulation of Star Formation in Low Metallicity Clouds

... mass dependence of the luminosity in the LW bands is rather weak, and hence even if the mass of the central star is smaller (< ∼ 10 M⊙ ), in this case the lifetime of the star is longer, star formation regulation can be efficient. Moreover, these less massive stars may not evolve into type II SNe. T ...
Chapter 3 Cosmology 3.1 The Doppler effect
Chapter 3 Cosmology 3.1 The Doppler effect

... Edwin Hubble was able to identify Cepheid variable stars in Andromeda. These stars vary in brightness with a period of the order of days and are named after the first one to be discovered, -Cephei, the fourth brightest star in the constellation Cepheus. Their significance is that the period depends ...
Chapter 17 Measuring the Stars
Chapter 17 Measuring the Stars

... 17.5 The Hertzsprung-Russell Diagram An H-R diagram of the 100 brightest stars looks quite different: These stars are all more luminous than the Sun. Two new categories appear here—the red giants and the blue giants. Clearly, the brightest stars in the sky appear bright because of their enormous lu ...
An Ancient Universe
An Ancient Universe

... the school science curriculum. The study of astronomy is deeply rooted in culture and philosophy. It harnesses our curiosity, imagination, and a sense of shared exploration and discovery, and it is also an area of great interest to people of all ages—especially children. With new and better telescop ...
Star Light, Star Bright
Star Light, Star Bright

... students that our star, the Sun, is a great distance from Earth, but that the next closest star is 272 times that distance from Earth! Write 149,600,000 km = Earth to Sun on the board; under it, write 40,678,000,000 km = Earth to Alpha Centauri. Tell students that Alpha Centauri is actually a triple ...
Properties of Supernovae
Properties of Supernovae

... Supernovae are rare events, occurring only once or twice per century in a typical galaxy. There have been just six supernovae seen in the Milky Way in recorded history, with the most recent occurring in 1604, just before the advent of telescopes. The perceptive reader will notice that this rate is m ...
110 - Institute for Astronomy
110 - Institute for Astronomy

... showing a quasi-regular series of dust lanes projecting from the arms of M51 (Scoville & Rector 2001). We investigate, using time-dependent numerical MHD simulations, how such spurs could form (and subsequently fragment) from the interaction of a gaseous interstellar medium with a stellar spiral arm ...
Distances of the Stars
Distances of the Stars

... The smallest parallax measurable from the ground is about 0.01-arcsec • Measure distances out to ~100 pc • Get 10% distances only to a few parsecs. • But, only a few hundred stars this close ...
astronomy
astronomy

... how these motions are accounted for by our understanding of how the Galaxy formed. Discuss some possible explanations for the existence of the spiral arms observed in our own and many other galaxies. Describe the basic properties of normal galaxies. Describe how galaxies are observed to clump into c ...
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H II region



An H II region is a large, low-density cloud of partially ionized gas in which star formation has recently taken place. The short-lived blue stars forged in these regions emit copious amounts of ultraviolet light that ionize the surrounding gas. H II regions—sometimes several hundred light-years across—are often associated with giant molecular clouds. The first known H II region was the Orion Nebula, which was discovered in 1610 by Nicolas-Claude Fabri de Peiresc.H II regions are named for the large amount of ionised atomic hydrogen they contain, referred to as H II, pronounced H-two by astronomers (an H I region being neutral atomic hydrogen, and H2 being molecular hydrogen). Such regions have extremely diverse shapes, because the distribution of the stars and gas inside them is irregular. They often appear clumpy and filamentary, sometimes showing bizarre shapes such as the Horsehead Nebula. H II regions may give birth to thousands of stars over a period of several million years. In the end, supernova explosions and strong stellar winds from the most massive stars in the resulting star cluster will disperse the gases of the H II region, leaving behind a cluster of birthed stars such as the Pleiades.H II regions can be seen to considerable distances in the universe, and the study of extragalactic H II regions is important in determining the distance and chemical composition of other galaxies. Spiral and irregular galaxies contain many H II regions, while elliptical galaxies are almost devoid of them. In the spiral galaxies, including the Milky Way, H II regions are concentrated in the spiral arms, while in the irregular galaxies they are distributed chaotically. Some galaxies contain huge H II regions, which may contain tens of thousands of stars. Examples include the 30 Doradus region in the Large Magellanic Cloud and NGC 604 in the Triangulum Galaxy.
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