Galaxies range greatly in size and composition. They are categorized based on their visual morphology as elliptical, spiral, irregular, barred spiral, lenticular, or peculiar galaxies. Elliptical galaxies have an ellipsoidal shape without much structure, while spiral galaxies have a central bulge and spiral arms. Irregular galaxies lack distinct shapes. Recent estimates indicate there are hundreds of billions to trillions of galaxies in the observable universe.
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.
A power point for a high school astronomy class which includes some basic information about stars in general including some links to other information.
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.
A power point for a high school astronomy class which includes some basic information about stars in general including some links to other information.
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.
In this guide, we explore the fascinating world of galaxies, those vast cosmic structures made up of billions of stars. We provide a deeper understanding of the different types of galaxies and the processes that shape their existence.
The journey begins with an introduction, setting the stage for our exploration. We then dive into the colossal islands of stars, discovering the mind-boggling scale of these galactic entities. From there, we delve into the intricate details of billions of stars, uncovering the magnitude and diversity within these cosmic neighborhoods.
We focus on spiral galaxies, investigating their graceful arms and mesmerizing beauty. We learn about their distinct features, such as the central bulge and spiral arms, and explore the different subtypes.
In contrast, we encounter elliptical galaxies, with their smooth and elongated shapes. We explore their origins and the processes that lead to their formation.
We also explore irregular galaxies, with their irregular shapes and diverse compositions. We examine their origins and the forces that contribute to their chaotic nature.
Supermassive black holes, lurking at the hearts of galaxies, are an essential part of the discussion. We delve into their formation, growth, and influence on galactic evolution.
As we progress further, we unravel the cosmic evolution of galaxies and explore the mechanisms that drive their formation and transformation over time.
Galaxy classification takes center stage as we examine different systems used by astronomers. We explore the Hubble sequence and its significance in understanding the diverse array of galactic structures.
We delve deeper into the classification of spiral galaxies, exploring their subtypes like barred spirals and their unique features.
Elliptical galaxies also receive a closer look as we investigate their classification system and the factors contributing to their diverse range of shapes and sizes.
We witness cosmic collisions between galaxies and explore the remarkable transformations that occur as a result, providing insights into galactic evolution.
Active galactic nuclei offer a glimpse into some of the most energetic phenomena in the universe. We examine the powerful forces at play within these galactic powerhouses and explore the supermassive black holes at their cores.
In conclusion, this comprehensive guide aims to provide a deeper understanding of galaxies, those awe-inspiring structures that have captivated humanity for centuries. Whether you are an amateur stargazer or a seasoned astronomer, we hope this resource will ignite your curiosity and inspire you to continue exploring the wonders of our vast universe.
Download our free PDF now and embark on a journey through the cosmos: https://theuniverseepisodes.com/what-is-galaxy-pdf-free-download/
Cosmic dinosaurs globular clusters and their fate wonderdome
If you look at the night sky with a telescope, you will notice fuzzy patches among the stars. Some of them are shapeless blobs, others are round. These are star clusters, the giant groups of stars held together by gravity.
introduction to galaxies in space.
chapter 9 earth and space class.
about the scientist edwin hubble.
and his theories. The study of asstronomy. space study of planets and galaxies.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
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.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
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.
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.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
2. A galaxy is a gravitationally bound
system of stars, stellar remnants,
interstellar gas, dust, and dark
matter.The word galaxy is derived
from the Greek galaxias , literally
"milky", a reference to the Milky Way.
Galaxies range in size from dwarfs
with just a few hundred million (108)
stars to giants with one hundred
trillion stars,(1014)each orbiting its
galaxy's center of mass.
3. Galaxies are categorized according to
their visual morphology as elliptical,
spiral, or irregular. Many galaxies are
thought to have black holes at their
active centers. The Milky Way's central
black hole, known as Sagittarius A*,
has a mass four million times greater
than the Sun.As of March 2016, GN-z11
is the oldest and most distant observed
galaxy with a comoving distance of 32
billion light-years from Earth, and
observed as it existed just 400 million
years after the Big Bang.
4. Recent estimates of the number of
galaxies in the observable universe range
from 200 billion (2×1011) to 2 trillion
(2×1012) or more,[8][9] containing more
stars than all the grains of sand on planet
Earth.[10] Most of the galaxies are 1,000
to 100,000 parsecs in diameter and
separated by distances on the order of
millions of parsecs (or megaparsecs).
5. The space between galaxies is filled
with a tenuous gas having an average
density of less than one atom per
cubic meter. The majority of galaxies
are gravitationally organized into
groups, clusters, and superclusters.
At the largest scale, these
associations are generally arranged
into sheets and filaments surrounded
by immense voids. The largest
structure of galaxies yet recognised
is a cluster of superclusters that has
been named Laniakea.
6. An elliptical galaxy is a type of galaxy
having an approximately ellipsoidal
shape and a smooth, nearly featureless
brightness profile. Unlike flat spiral
galaxies with organization and
structure, they are more three-
dimensional, without much structure,
and their stars are in somewhat
random orbits around the center.
7. They are one of the three main classes of galaxy
originally described by Edwin Hubble in his 1936
work The Realm of the Nebulae, along with spiral
and lenticular galaxies. Elliptical galaxies range in
shape from nearly spherical to highly flat and in
size from tens of millions to over one hundred
trillion stars. Originally Edwin Hubble
hypothesized that elliptical galaxies evolved into
spiral galaxies, which was later discovered to be
false.Stars found inside of elliptical galaxies are on
average much older than stars found in spiral
galaxies.
8. Spiral galaxies form a class of
galaxy originally described by
Edwin Hubble in his 1936 work
The Realm of the Nebulae and,
as such, form part of the
Hubble sequence. Most spiral
galaxies consist of a flat,
rotating disk containing stars,
gas and dust, and a central
concentration of stars known as
the bulge. These are often
surrounded by a much fainter
halo of stars, many of which
reside in globular clusters.
9. Spiral galaxies are named by their spiral structures that
extend from the center into the galactic disc. The spiral arms
are sites of ongoing star formation and are brighter than the
surrounding disc because of the young, hot OB stars that
inhabit them.
Roughly two-thirds of all spirals are observed to have an
additional component in the form of a bar-like
structure,extending from the central bulge, at the ends of
which the spiral arms begin. The proportion of barred
spirals relative to their barless cousins has likely changed
over the history of the Universe, with only about 10%
containing bars about 8 billion years ago, to roughly a
quarter 2.5 billion years ago, until present, where over two-
thirds of the galaxies in the visible universe (Hubble
volume) have bars.
10. In the 1970s, our own Milky Way was confirmed to
be a barred spiral, although the bar itself is difficult
to observe from the Earth's current position within
the galactic disc. The most convincing evidence for
the stars forming a bar in the galactic center comes
from several recent surveys, including the Spitzer
Space Telescope .
Together with irregular galaxies, spiral galaxies
make up approximately 60% of galaxies in today's
universe.They are mostly found in low-density
regions and are rare in the centers of galaxy
clusters.
11. An irregular galaxy is a
galaxy that does not have a
distinct regular shape,
unlike a spiral or an
elliptical galaxy. Irregular
galaxies do not fall into
any of the regular classes
of the Hubble sequence,
and they are often chaotic
in appearance, with
neither a nuclear bulge nor
any trace of spiral arm
structure.
12. Collectively they are thought to make up about a
quarter of all galaxies. Some irregular galaxies
were once spiral or elliptical galaxies but were
deformed by an uneven external gravitational
force. Irregular galaxies may contain abundant
amounts of gas and dust.This is not necessarily
true for dwarf irregulars.
Irregular galaxies are commonly small, about one
tenth the mass of the Milky Way galaxy. Due to
their small sizes, they are prone to environmental
effects like crashing with large galaxies and
intergalactic clouds.
13. A barred spiral galaxy is a spiral
galaxy with a central bar-shaped
structure composed of stars. Bars are
found in approximately two-thirds of
all spiral galaxies. Bars generally
affect both the motions of stars and
interstellar gas within spiral galaxies
and can affect spiral arms as well.The
Milky Way Galaxy, where our own
Solar System is located, is classified as
a barred spiral galaxy.
14. Edwin Hubble classified spiral galaxies of this type as
"SB" (spiral, barred) in his Hubble sequence and
arranged them into sub-categories based on how open
the arms of the spiral are. SBa types feature tightly
bound arms, while SBc types are at the other extreme
and have loosely bound arms. SBb-type galaxies lie in
between the two. SB0 is a barred lenticular galaxy. A
new type, SBm, was subsequently created to describe
somewhat irregular barred spirals, such as the
Magellanic Cloud galaxies, which were once classified
as irregular galaxies, but have since been found to
contain barred spiral structures. Among other types in
Hubble's classifications for the galaxies are the spiral
galaxy, elliptical galaxy and irregular galaxy.
15. A lenticular galaxy is a type of
galaxy intermediate between an
elliptical and a spiral galaxy in
galaxy morphological classification
schemes. Lenticular galaxies are
disc galaxies (like spiral galaxies)
that have used up or lost most of
their interstellar matter and
therefore have very little ongoing
star formation. They may,
however, retain significant dust in
their disks.
16. As a result, they consist mainly of aging stars
(like elliptical galaxies). Because of their ill-
defined spiral arms, if they are inclined face-on
it is often difficult to distinguish between them
and elliptical galaxies. Despite the
morphological differences, lenticular and
elliptical galaxies share common properties like
spectral features and scaling relations. Both can
be considered early-type galaxies that are
passively evolving, at least in the local part of
the Universe.
17. A peculiar galaxy is a galaxy of
unusual size, shape, or
composition. Between five and ten
percent of known galaxies are
categorized as peculiar.
Astronomers have identified two
types of peculiar
galaxies: interacting
galaxies and active galactic
18. When two galaxies come close to each other,
their mutual gravitational forces can cause
them to acquire highly irregular shapes The
terms 'peculiar galaxy' and 'interacting galaxy'
have now become synonymous because the
majority of peculiar galaxies attribute their
forms to such gravitational forces.