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Notes 6 - University of Northern Iowa
Notes 6 - University of Northern Iowa

... are particles that easily absorb energy, particularly large gas molecules and dust. Such large molecules can exist in the outer layers of these cool stars, and have been observed. The winds in these stars are actually best described as superwinds. These are the types of winds we see when we see larg ...
The Milky Way Laboratory
The Milky Way Laboratory

... Next Steps: The Skeleton of the Milky Way • Identify more Bones of the Milky Way. Combine with other tracers (e.g. CO, HI, dense gas) to develop a model of Galactic structure • Measure physical properties and kinematics of Bones – compare directly with simulations. Develop improved Galactic-scale s ...
File - Mr. Gray`s Class
File - Mr. Gray`s Class

... estimate is that the Galaxy comprises some 200 billion to 400 billion stars and a vast amount of raw material (atoms, molecules and dust). Much of this raw material does not give off visible light (although we have observed it using other kinds of waves). Still, in a few places, the light of nearby ...
MAIN SEQUENCE STARS, Red Giants and White Dwarfs
MAIN SEQUENCE STARS, Red Giants and White Dwarfs

... • A star leaves the MS when it exhausts H at the core. During the MS, there is an excellent balance between P and gravity: HYDROSTATIC EQUILIBRIUM • When H is gone, the core is essentially all He and (at between 6 and 40 million K), far too cool to start nuclear fusion of He. • The structure must re ...
A Drastic Chemical Change Occurring in Birth of Planetary System
A Drastic Chemical Change Occurring in Birth of Planetary System

... ALMA is funded in Europe by the European Southern Observatory (ESO), in North America by the U.S. National Science Foundation (NSF) in cooperation with the National Research Council of Canada (NRC) and the National Science Council of Taiwan (NSC) and in East Asia by the National Institutes of Natura ...
I Introduction to the Interstellar Medium
I Introduction to the Interstellar Medium

... The first observational evidence that there was a general ISM that pervaded the space between the stars came from photographic spectroscopy of spectroscopic binary stars early in the 20th century. It was noticed that in addition to the relatively broad absorption lines associated with the atmosphere ...
File - Mr. Catt`s Class
File - Mr. Catt`s Class

... 2. Look-back time is the time light from a distant object has traveled to reach us. 3. The look-back time complicates our interpretation of galaxies because the farther out we look, the earlier in time we are seeing them. – Our assumption that distant clusters are similar to nearby clusters may not ...
SGL 9 NGC Galaxy magnitude 9/10 observing challenge Up for
SGL 9 NGC Galaxy magnitude 9/10 observing challenge Up for

... Once you have seen a few spirals face on you will find you can identify them even before you have looked them up on google! Object 3 – Leo triplet (Taki page 50) No not the famous one. Look half way between delta and theta Leo and then a fraction left. This group NGC3605 / NGC 3607 and NGC 3608 are ...
Primordial Planet Formation - University of California San Diego
Primordial Planet Formation - University of California San Diego

... ordinary
dark
matter.

Hydrogen
is
a
gas
that
condenses
to
liquid
and
then
forms
 solid
ice
at
low
temperatures.


It
has
large
latent
heats
of
evaporation
and
fusion,
so
 a
thermostat
temperature
range
between
the
triple
point
temperature
and
critical
 temperature
is
the
signature
of
a
cloud
of
gas ...
Abundances of RGB stars in NGC 6752 Grundahl
Abundances of RGB stars in NGC 6752 Grundahl

... The primordial scenario, and variations on it, has been proposed and discussed several times before in the literature (see for example Cottrell & Da Costa 1981, and Cannon et al. 1998). The small star–to–star scatter in the iron peak elements (as observed in this work) indicates that the contributio ...
THE HERTZSPRUNG-RUSSELL DIAGRAM
THE HERTZSPRUNG-RUSSELL DIAGRAM

... The age of a cluster is given by the main sequence turn-off point—the highest point on the main sequence that is still populated by stars. On the left is a wellknown schematic diagram combining the HR diagrams of star clusters of different ages: NGC2362 is the youngest and M67 the oldest. The pink n ...
Available online www.jsaer.com Journal of Scientific and
Available online www.jsaer.com Journal of Scientific and

... colours remained a mystery until two centuries ago, when Physicists gained enough light of the nature of light and the properties of matter at immensely high temperatures [7]. Specifically, it was the physics of blackbody radiation that enabled us to understand the variation of stellar colours. Shor ...
Here
Here

... depends on the initial mass of the star. • Although there is a continuous range of masses, there are 4 ranges of masses that capture all of the interesting features. ...
THE ORION NEBULA AND ITS ASSOCIATED POPULATION C. R. O
THE ORION NEBULA AND ITS ASSOCIATED POPULATION C. R. O

... was inconsistent with a spherically symmetric nebula and was used independently and essentially simultaneously by Balick et al. (1974) and Zuckerman (1973) to come up with today’s model. In a simple manner, the assumption of a thin emitting layer of radially decreasing density lying beyond the ioniz ...
THE ORIGIN AND EVOLUTION OF PLANETARY NEBULAE
THE ORIGIN AND EVOLUTION OF PLANETARY NEBULAE

... Planetary nebulae as a phase of stellar evolution At the beginning of the 20th Century, when stars were believed to evolve from high temperatures to low temperatures, PN were thought to be very young stars because of their high temperatures. From his studies of the velocity distribution of PN, Curti ...
Quasars
Quasars

... • Quasars give off more energy than 100 normal galaxies combined. • Quasars give off such enormous amounts of energy that they can be a trillion times brighter than the Sun. • Quasars are so bright that they drown out the light from all the other stars in the same galaxy. • Most quasars are larger t ...
13.1 Introduction 13.2 The Red Giant Branch
13.1 Introduction 13.2 The Red Giant Branch

... Grains are microscopic solid particles that can condense out of the gas phase at the values of temperature and pressure typical of the extended atmospheres of late-type giant and supergiant stars. Their presence in these environments is indicated by a number of infrared spectral features, such as th ...
The Next 2-3 Weeks
The Next 2-3 Weeks

... Define: Dn = angular diameter at which surface brightness reaches In = 20.75 B-mag/arcsec2 ...
Lesson 4 - Scientist in Residence Program
Lesson 4 - Scientist in Residence Program

... people a star’s colour and brightness is highly dependent on its size. We can get clues about how hot a star is and a star’s age from a star’s colour. Stars are often classified based on size, temperature and spectra (or its colour). There are 7 main types of stars: O, B, A, F, G, K and M (easy mnem ...
constellation.
constellation.

... (Your project should include: how many kilometers there are in 1 AU and 1 light year along with some interesting distances in space using these measurements, such as, distance from the Sun to Earth, from Earth to the next nearest star and at least 5 other interesting distances in the Universe) d. St ...
Space astrometry 2: Scientific results from Hipparcos
Space astrometry 2: Scientific results from Hipparcos

... • Ursa Major: 0.3 Gyr (Eggen 1998, Chupina et al 2001, King et al 2003) • HR 1614: 2-6 Gyr (Eggen 1998, Feltzing & Holmberg 2000) ...
Quasar feedback revealed by giant molecular outflows
Quasar feedback revealed by giant molecular outflows

... of M 82 (a typical starburst galaxy), including its molecular outflow (Weiss et al. 2001). We derive a mass of the outflowing molecular gas M(H2 ) = 5.8 × 108 M , which is consistent with the lower limit of 7 × 107 M inferred by Fischer et al. (2010) based on the absorption molecular lines detecte ...
doc - Pocket Stars
doc - Pocket Stars

... screen. Click it again to hide the menu. Further clicks toggle between object selection and scrolling modes. Non-QWERTY devices can quickly change to various zoom factors by hitting a number key to zoom smoothly in and out. The most important keys are: ...
Fate of Stars
Fate of Stars

... •  In WD, gravity is balanced by pressure due to degenerate electrons •  A heavier WD will have smaller radius •  if Mass(WD) > 1.4 M(Sun) electrons can not resist gravity ! called Chandrasekhar limit and no WD has a mass greater than this •  If WD can acquire mass from companion star and goes over ...
PDF format
PDF format

... a)  True, galaxy clusters have a much higher percentage of elliptical galaxies than do other parts of the universe. b)  True, elliptical galaxies are found exclusively in galaxy clusters. c)  False, elliptical galaxies are more commonly found away from galaxy clusters. d)  False, elliptical galaxies ...
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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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