The document discusses two models of galaxy formation:
1) The classical or monolithic model which proposes that galaxies form in isolation with little environmental impact.
2) The hybrid hierarchical model which proposes that galaxies form through successive mergers of smaller bodies and their evolution depends more on their environment. The document provides evidence that supports the hierarchical model including cold dark matter, observations of small blue galaxies, star formation rates, cluster shapes, and observations of the Hubble Deep Field. It also discusses properties of active galaxies, quasars, and differences between normal and active galaxies.
It presents about normal galaxy and how it differs to other type of galaxy. The types of galaxies are also presented like spiral galaxies, barred spiral, ellipticals, lenticulars and irregular galaxies with examples and pictures for further explanation.
It presents about normal galaxy and how it differs to other type of galaxy. The types of galaxies are also presented like spiral galaxies, barred spiral, ellipticals, lenticulars and irregular galaxies with examples and pictures for further explanation.
A lecture I'd given on spiral galaxies, barred spirals, mass of galaxies, Sgr A, Elliptical galaxies, standard candles, dark matter, composition of the universe, back in my university days.
You probably need to download the file for the animations to work.
The universe is the totality of all matter and energy, originating with the big bang and expanding outwards. There is no outside to it, although there may
A talk I gave on Secular (Slow) Processes and Galaxy Evolution given at the Evolutionary Paths in Galaxy Evolution (or "Galaxy Zoo") conference held in Sydney, Sept 2013. (http://www.atnf.csiro.au/research/conferences/2013/gzo/)
A lecture I'd given on spiral galaxies, barred spirals, mass of galaxies, Sgr A, Elliptical galaxies, standard candles, dark matter, composition of the universe, back in my university days.
You probably need to download the file for the animations to work.
The universe is the totality of all matter and energy, originating with the big bang and expanding outwards. There is no outside to it, although there may
A talk I gave on Secular (Slow) Processes and Galaxy Evolution given at the Evolutionary Paths in Galaxy Evolution (or "Galaxy Zoo") conference held in Sydney, Sept 2013. (http://www.atnf.csiro.au/research/conferences/2013/gzo/)
YEAR 9 GEOGRAPHY - ASTRONOMY: SUN, PLANETS AND GALAXYGeorge Dumitrache
An original and comprehensive Powerpoint presentation about the science of Astronomy: the Sun, the planets and our galaxy. It is suitable for Year 9 and 10, pre Cambridge curricula.
Why do we believe galaxy clusters are rich in dark matter What is b.pdffabmallkochi
Why do we believe galaxy clusters are rich in dark matter? What is believed to be the large-
scale structure of the universe?
Solution
1)
Dark matter is a mysterious cosmic phenomenon that accounts for 27 percent of all matter and
energy. Though dark matter is all around us, we cannot see it or feel it. But scientists can infer
the presence of dark matter by looking at how normal matter behaves around it.
Galaxy clusters, which consist of thousands of galaxies, are important for exploring dark matter
because they reside in a region where such matter is much denser than average. Scientists believe
that the heavier a cluster is, the more dark matter it has in its environment. But new research
suggests the connection is more complicated than that.
A new study suggests that the internal structure of a galaxy cluster is linked to the dark matter
environment surrounding it. Hence this property besides the mass of a cluster is shown to be
associated with surrounding dark matter.
Researchers studied approximately 9,000 galaxy clusters from the Sloan Digital Sky Survey DR8
galaxy catalog, and divided them into two groups by their internal structures: one in which the
individual galaxies within clusters were more spread out, and one in which they were closely
packed together. The scientists used a technique called gravitational lensing -- looking at how the
gravity of clusters bends light from other objects -- to confirm that both groups had similar
masses.
But when the researchers compared the two groups, they found an important difference in the
distribution of galaxy clusters. Normally, galaxy clusters are separated from other clusters by
100 million light-years on average. But for the group of clusters with closely packed galaxies,
there were fewer neighboring clusters at this distance than for the sparser clusters. In other
words, the surrounding dark-matter environment determines how packed a cluster is with
galaxies.
2)
The standard model of cosmology indicates that the total mass–energy of the universe contains
4.9% ordinary matter, 26.8% dark matter and 68.3% dark energy.Thus, dark matter constitutes
84.5% of total mass, while dark energy plus dark matter constitute 95.1% of total mass–energy
content. The great majority of ordinary matter in the universe is also unseen, since visible stars
and gas inside galaxies and clusters account for less than 10% of the ordinary matter contribution
to the mass-energy density of the universe..
This is a very broad overview of cosmology. It includes an introduction to galaxies, the large scale structure of the universe, black holes, and the fate of the universe. It is intended for teenagers and up.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
Honest Reviews of Tim Han LMA Course Program.pptxtimhan337
Personal development courses are widely available today, with each one promising life-changing outcomes. Tim Han’s Life Mastery Achievers (LMA) Course has drawn a lot of interest. In addition to offering my frank assessment of Success Insider’s LMA Course, this piece examines the course’s effects via a variety of Tim Han LMA course reviews and Success Insider comments.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Acetabularia Information For Class 9 .docxvaibhavrinwa19
Acetabularia acetabulum is a single-celled green alga that in its vegetative state is morphologically differentiated into a basal rhizoid and an axially elongated stalk, which bears whorls of branching hairs. The single diploid nucleus resides in the rhizoid.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
2. Two Models of Galaxy
Formation and Evolution
The Classical or Monolithic Model
•proposes that galaxies form and evolve
as relatively isolated bodies.
•In this scenario galaxies evolve in a
pre-determined fashion dependant on
the initial conditions and with relatively
little impact from the surrounding
environment
3. The Hybrid Hierarchical Model
proposes that galaxies
form and evolve through
successive mergers of
smaller bodies and their
fate is more dependent on
the environment which
they inhabit.
4. Figure 1: The two competing models of galaxy formation and evolution that
could produce the galaxies we observe today. The classical ‘top down’ or
monolithic model is shown on the left. This involves the collapse of a large
cloud over time. The hierarchical or ‘bottom up’ model is shown on the right and
involves successive mergers of small bodies.
5. Figure 2: A simplified schematic of the hybrid
hierarchical model of galaxy formation and evolution .
6. The Evidences
1.Cold Dark Matter (CDM)
It is created in the early stages of the Big
Bang and survives to the present time in
sufficient numbers to contribute
significantly to the present density of the
Universe. The term ‘cold’ signifies that
these particles move at speeds much less
than that of light, usually because they are
heavy.
7. 2. Blue Galaxy
Figure 5: These 18 small blue objects imaged by the HST could be the
precursors to galaxies we see in the universe today.
8. 3. Star Formation Rate (SFR)
The history of recent star formation from the recent compilation of Blain (2000). Data
points are taken from a variety of sources referenced in that article. Thick solid and
dashed lines represent trends expected from simple luminosity evolution and hierarchical
models, respectively. It is clear there is considerable observational scatter at all
redshifts, not just beyond z 1 as often assumed.
9. Cluster of Galaxies
are the largest known gravitationally bound
objects to have arisen thus far in the process of
cosmic structure formation. They form the
densest part of the large scale structure of the
universe. In models for the gravitational
formation of structure with cold dark matter,
the smallest structures collapse first and
eventually build the largest structures, clusters
of galaxies. Clusters are then formed relatively
recently between 10 billion years ago and now.
Groups and clusters may contain from ten to
thousands of galaxies.
.
10. Two classes of Clusters in terms of shape
1. Regular Clusters
are relatively compact, with highest
density near the center. Members are
mostly elliptical galaxies.
2. Irregular Clusters
including our Local Group, have a looser
structure with little central
concentration and less very hot gas.
11. Superclusters
large groups of smaller galaxy groups and
clusters and are among the largest
structures of the cosmos. They are so
large that they are not gravitationally
bound and, consequently, partake in the
Hubble expansion
14. How Did Large-Scale Structure
Evolve In The Universe?
The Hubble Deep Field will be used to perform a
statistical study of the distribution of galaxies on
the sky. This is an essential test of models for the
structure of the universe and galaxy formation
theories. Predicting how clustering should vary
with brightness (or other galaxy properties) is a
key challenge to models of structure formation.
Current observations show that galaxies tend to
cluster around other galaxies. However, the
faintest galaxies are almost randomly distributed
on the sky. The Hubble Deep Field will push such
studies to fainter limits.
15. Active Galaxies
A galaxy emitting unusually high quantities of radiation from
an active galactic nucleus at its center. Some active galaxies
emit more energy in radio wavelengths than they do visible
light
Properties:
(1) High Luminosity,
(2) Nonthermal Spectra that do not look like the sum of many
stellar spectra,
(3) Most of the luminosity is in a region of the spectrum other
than optical (e.g., radio, UV, Infrared),
(4) bright, star-like nucleus,
(5) strong emission lines (most),
(6) rapid variability, and sometimes
(7) radio jets.
17. Normal galaxy
one that does not have material for the
supermassive black hole to "feed" on. But
even if these normal galaxies are quite in
regards to core activity, they still emit in
other wavelengths.
20. Quasars
a very energetic and distant active
galactic nucleus. Quasars are the most
luminous objects in the universe.
Quasars were first identified as being
high redshift sources of electromagnetic
energy, including radio waves and visible
light, that were point-like, similar to stars,
rather than extended sources similar
to galaxies.
21. The region of the sky containing one of the high-energy quasars, PKS 0528+134, is shown
at two different times using the EGRET instrument on the Compton Gamma-Ray
Observatory These active galaxies are highly variable, strongly emitting gamma-rays
sometimes, disappearing at other times.