formation of galaxies and universe and its galaxies.ppt

galaxies and universe

2. A light year is a way of measuring
distance.

3. Light travels at 186,000 miles per second
(300,000 kilometers per second).
Therefore, a light second is 186,000 miles
(300,000 kilometers).
A light year is the distance that light can
travel in a year, or:
186,000 miles/second * 60 seconds/minute
* 60 minutes/hour * 24 hours/day * 365
days/year = 5,865,696,000,000 miles/year
OR…… 1 LIGHT YEAR

4. the branch of astronomy that deals with
the origin, large-scale properties, and
the evolution of the observable universe
the
branch
of
astronom
y that
deals
with the
origin,
large-
scale
propertie
s, and
the
evolution
of the
observab
le
universe

5. in astronomy, the sum total of all things which
can be directly observed or whose physical
effects on other things can be detected
in simpler terms, space and all the matter and
energy in it
major components:
•galaxies
•solar systems
•planets

6. •The universe
began with a hot
explosion called
the Big Bang.
The aftermath of
the Big Bang
consisted
mostly of
radiation, but as
things cooled,
the elements
hydrogen and
helium formed.
•http://imgsrc.hubblesite.org/hu/e
xplore_astronomy/skywatch/db/3
07/audio/SkyWatch_307-11252010
.mp3

8. the primeval explosion of space, time, matter and
energy that most astronomers think gave rise to the
universe as we see it today.
occurred about 13.7 billion years ago
thought to have expanded within a second from
something the size of a spec of dust to the size of
our solar system

9. •Big Bang Theory - Evidence for the Theory
•First of all, we are reasonably certain that the universe
has a beginning.
•Second, galaxies appear to be moving away from us at
speeds proportional to their distance. This is called
"Hubble's Law.” This observation supports the
expansion of the universe and suggests that the
universe was once compacted.
•Third, if the universe was initially very, very hot as the
Big Bang suggests, we should be able to find some
remnant of this heat. In 1965, this was discovered a 2.725
degree Kelvin (-454.765 degree Fahrenheit, -270.425 degree Celsius) Cosmic
Microwave Background radiation (CMB) which pervades the observable universe.

•Finally, the abundance of the "light elements"
Hydrogen and Helium found in the observable
universe are thought to support the Big Bang model of
origins.

10. A cloud in space made of gas and dust which can have
stars inside
Most of the ones we see are inside our Milky Way Galaxy
Orion image at
http://hubblesite.org/newscenter/archive/releases/2006/01/image/a/resul
ts/50/

11. Basis of modern theory
of planet formation.
Planets form at the
same time from the
same cloud as the star.
Sun and our solar system
formed ~ 5 billion years ago.
Planet formation sites
observed today as dust
disks of T Tauri stars.

12. a), (b) The solar nebula contracts and
flattens into a spinning disk. The
large blob in the center will become
the Sun. Smaller blobs in the outer
regions may become jovian planets.
(c) Dust grains act as condensation
nuclei, forming clumps of matter that
collide, stick together, and grow into
moon-sized planetesimals.
(d) Strong winds from the still-
forming Sun expel the nebular gas.
(e) Planetesimals continue to collide
and grow.
 (f) Over the course of a hundred
million years or so, planetesimals
form a few large planets that travel in
roughly circular orbits.

13. The Big Bang Theory considers the
creation of all the matter and energy that
exists in the universe.. Anywhere..
The Solar Nebula theory uses that matter
and energy, to create galaxies and solar
systems.

14. A large group of stars outside of our own Milky
Way
Made of billions to trillions of stars
•Also may have gas and dust
Spiral, or elliptical, or irregular shaped
Image at
http://hubblesite.org/newscenter/archive/releases/galaxy/spiral/2007/41/
results/50/

15. Spiral
have arms of stars, gas ,
and dust that curve away
from the center of the
galaxy in a spiral pattern
Ex. – Milky Way
Elliptical
shaped like
spheres or eggs;
have almost no
dust or gas
between stars;
contain old stars
Irregular
faint galaxies without
a definite shape;
smaller than the
other types of
galaxies; contain
fewer stars
The process of galaxies colliding to create a larger galaxy is known
as “galactic cannibalism.”
Images taken from: http://school.discoveryeducation.com/schooladventures/universe/galaxytour/toknow.html

16. NOAO/AURA/NSF Images at
http://www.noao.edu/image_gallery/html/im0606.html and
http://www.noao.edu/image_gallery/html/im0685.html

17. Located in the constellation of Andromeda,
the Princess, the Andromeda Galaxy is a
large spiral galaxy very similar to our
own Galaxy, the Milky Way. It is over
65,000 light-years in diameter and
approximately 2.2 million light-years in
distance.

18. Images at
http://hubblesite.org/newscenter/archive/releases/galaxy/elliptical/2007/08/image/
a/format/large_web/results/50/
and
http://hubblesite.org/newscenter/archive/releases/galaxy/elliptical/1995/07/results/
50/

NGC 4881

19. The giant elliptical ESO 325-G004 looms large at
the cluster's center. The galaxy is as massive as
100 billion of our suns. Hubble resolves
thousands of globular star clusters orbiting ESO
325-G004. Globular clusters are compact groups
of hundreds of thousands of stars that are
gravitationally bound together. At the galaxy's
distance they appear as pinpoints of light
contained within the diffuse halo.

20. NASA and NOAO/AURA/NSF Images at
http://hubblesite.org/newscenter/archive/releases/galaxy/irregular/2005/09/resu
lts/50/
, http://www.noao.edu/image_gallery/html/im0560.html , and
http://www.noao.edu/image_gallery/html/im0993.html

21. The irregular galaxy NGC 1427A is a spectacular example of the resulting stellar
rumble. Under the gravitational grasp of a large gang of galaxies, called the Fornax
cluster, the small bluish galaxy is plunging headlong into the group at 600
kilometers per second or nearly 400 miles per second.
1. IS NGC 1427A ACTIVELY FORMING STARS?
NGC 1427A shows numerous hot, blue stars that have been formed very recently,
showing that star formation is occurring extensively throughout the galaxy. Within
the Fornax cluster, there is a considerable amount of gas lying between the galaxies.
When the gas within NGC 1427A collides with the Fornax gas, it is compressed to the
point that it starts to collapse under its own gravity. This leads to formation of the
myriad of new stars seen across NGC 1427A. The tidal forces of nearby galaxies in
the cluster may also play a role in triggering star formation on such a massive scale.
2. WHAT IS THE EVENTUAL FATE FOR NGC 1427A?

NGC 1427A will not survive long as an identifiable galaxy passing through the
cluster. Within the next billion years, it will be completely disrupted, spilling its stars
and remaining gas into intergalactic space within the Fornax cluster.

22. has about 200 billion stars, and lots of
gas and dust
is a barred-spiral
about 100,000 light-years wide
our Sun is halfway to the edge, revolving
at half a million miles per hour around
the center of the Galaxy
takes our Solar System about 200
million years to revolve once around our
galaxy

23. Image at
http://news.nationalgeographic.com/news/bigphotos/194
5371.html

24. determined that other
galaxies exist, besides
the Milky Way
observed that galaxies
were moving away from
each other
•Hubble Law – the farther
away a galaxy is, the
faster it is moving away
from us; supports the Big
Bang Theory Image taken from:
http://apod.nasa.gov/apod/ap960217.html

25. accidentally detected faint radiation on
a radio telescope in 1965
determined that the radiation was
leftover thermal energy from the “big
bang”
Image taken from:
http://www.einstein-online.info/en/elementary/cosmology/early_universe/index.html

26. a large assemblage of stars (and often gas and dust), typically
containing millions to hundreds of billions of member stars
•Star - a large hot ball of gas which generates energy in its core by nuclear
reactions
around 100 billion in the universe
held together by the gravitational attraction of all its member
stars on one another
formed around 200 million years after the “Big Bang”
most large ones seem to have super-massive black holes at their
centers
sometimes contain very bright centers called quasars
3 major types:
•Spiral
•Elliptical
•Irregular
What is the name
of the galaxy
we reside in?

27. a group of stars that form a pattern in the sky
stars of a constellation are often far apart from each
other, but they appear grouped together when viewed from
Earth
one of 88 sectors into which astronomers divide the
sphere of the sky – named after a traditional constellation
in that sector
patterns of constellations are dynamic; therefore, the
constellations of 100,000 years ago are quite different
from today’s
a part of a constellation that forms its own pattern in the
sky is known as an asterism (ex. – The Big Dipper)
Why is it not possible to see all constellations at once?

28. the sun and all things orbiting around it,
including the eight major planets, their
satellites, and all the smaller pieces such as
asteroids and comets
formed around 4.6 billion years ago
Image taken from:
http://asm.arc.nasa.gov/Gallery/images/generic/LG_Capableofeverything.jpg
What is
incorrect
or misleading
about this
visual?

29. HOW DID THE SOLAR SYSTEM FORM?
• Star formation occurs in our Galaxy.
• The Milky Way, is an Interstellar Cloud, known
as Giant Molecular Clouds.
• Solar Nebula (90% Hydrogen, 9% Helium)

30. • Solar Nebula, collapses in on center
under influence of gravity.
• Conservation of angular momentum,
causes faster spinning and flattening
into disk.

31. • Eventually greatest mass concentrated in center
(Sun) with a disk of rotating cold matter around it.

32. • Small dust particles and material ejected
from former stars collide and coalesce as
they rotate.
• Form Planetisimals several 100
kilometers in diameter.

33. •Gravitational pull of larger and larger
Planetisimals grows, increasing their mass, and
their gravity.

•Creating Protoplanets consisting of random
collections of dust, rock and gas from various
origins.
•Collected cold and held together by gravity,
with no apparent order -“Cold Accretion
Hypothesis.”

34. • Density and concentration of mass in Sun
creates sufficient temperature and pressure to
generate nuclear fusion and Sun starts to “burn”
forging Hydrogen to Helium, and other
conversions. “Stellar Workshops”.
• Generation of charged particles called Solar
Wind.
SU
N
Small
Rocky
Gaseous
Giants
Close
Distant

35. derived from a Greek word
that means “wanderer”
a major object which orbits
around a star
in our solar system, there are
eight such objects which are
traditionally called “planets”

36. small, solid, rocky
bodies that orbit close
to the Sun
most found between
the orbits of Mars and
Jupiter in the “
Asteroid Belt”
thought to be leftover
material from the
formation of the solar
system
range in size from
1000 km or 621 miles
(Ceres) to the size of
pebbles
Image taken from:
http://www.windows.ucar.edu/tour/link=/our_solar_system/asteroids.html

37. Gaseous
Giants:
Jupiter
Saturn
Neptune
Uranus

38. Gaseous
Giants:
Jupiter
Saturn
Neptune
Uranus
Small
Rocky:
Mercury
Venus
Earth
Mars

39. Gaseous
Giants:
Jupiter
Saturn
Neptune
Uranus
Small
Rocky:
Mercury
Venus
Earth
Mars
Recently
Relegated:
Pluto

40. 1. Cold Accretion.
Random
organization of
various chemical
elements.
“Cosmic Oh Henry bar”

41. 2. Internal source of energy: Energy
stored in composites from the time of
the “Big Bang”, internal friction and
radioactive decay. The larger the
protoplanet the more difficult it
becomes for energy to escape.

42. 3. External source of energy: Early in
the Earth’s history there is still plenty
of material in the path of the
protoplanet’s orbit, which is constantly
being attracted by the Earth’s gravity
to the every enlarging planet.
Collisions of these meteorites into the
Earth’s surface are a constant source
of energy and melting.
Chicxulub
65m y
Barringer Meteor Crater, AZ
50,000 y
Shoemaker – Levy 9
20 y

43. 4. Internal separation by density: A slow
process that still continues to this day, moves
the least dense chemical constituents to the
outside of the Earth (“lighter material floats”),
and densest chemicals to the interior
(“heavier materials sink”).
Least dense
materials
Most dense
materials
Gradual
increase in
densities of
materials.
Density
gradient.

44. Meteoroid – solid debris from space
(asteroids) that are moving towards
Earth
Meteor
•a brief streak of light produced by a
small particle entering Earth’s
atmosphere at high speed
•often referred to as “shooting
stars” or “falling stars”
•travel at speeds between 11-72
kilometers per second (6.8 – 44.7
miles per second)
Meteorite – a small object from
outer space that passes through
Earth’s atmosphere and reaches
the surface
Freehold Meteorite - MSNBC
Freehold Meteorite - USA-Today
Meteoroid (asteroid)
Meteor
Meteorite
The Earth
animation is
not rotating
in the
correct
direction;
it should be
rotating
from west to
east
What causes a meteor
shower to occur?

45. a small body of ice and
dust (“dirty snowball”)
that orbits the Sun
contain a head (coma)
followed by a tail(s) of
gas and dust
the tail always points
away from the sun and
can be millions of
kilometers long (but the
amount of matter it
contains can be very
small)
Image taken from:
http://www.space.com/bestimg/index.php?guid=45b0fd31f065d&cat=bestcomet

46. an object that orbits a more massive
object (i.e. – moons)
probes we launch into orbit around the
Earth are called “artificial satellites”
The Earth
animation is
not rotating
in the
correct
direction;
it should be
rotating
from west to
east

47. a device that gathers electromagnetic radiation
Types:
•Visible, infrared, ultraviolet – pick up visible,
infrared, and ultraviolet waves
Reflecting - use mirrors that reflect the image being
viewed
Refracting – using lenses, gathers light and focuses it near
the opposite end of the tube; works like a magnifying glass
•Radio - pick up radio waves emitted from space;
not effected by variables like weather or clouds
Internet Telescope

48. a reflecting
telescope that was
placed into orbit in
1990
sends images and
measurements back
to Earth
electronically
What is one of the main
benefits of having the Hubble Space
Telescope in orbit, as opposed to
it being here on Earth?
Image taken from:
http://hubblesite.org/gallery/

49. unit of distance equal to the average spacing
between the Earth and the Sun
equal to about 150 million kilometers (93
million miles)
light takes about eight minutes to cover this
distance
150 million km
(93 million mi.)
The Earth
animation is
not rotating
in the
correct
direction;
it should be
rotating
from west to
east

50. unit of distance equal to about 3.26
light years (or 206,265 AU)
If one parsec equals 206, 265 AU, how
many miles is it equal to?

51. the apparent shift in position of an
object when viewed from different
locations
used by astronomers to measure
distance
Parallax Simulation
Parallax Simulation – 1
Parallax Simulation - 2
Find the Distance to HT Cas Using Parallax
Put your pointer finger in front of your face and begin
opening and closing your eyes in an alternating manner. What
do you notice about the your finger’s position?