1. Solar system
2. Stars
3. Milky Way
4. Galaxies
5. Clusters and super-clusters
6. Cosmological principle (homogenous and isotropic)
How big is the Universe
How big is the Universe
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1. Solar system
2. Stars
3. Milky Way
4. Galaxies
5. Clusters and super-clusters
6. Cosmological principle (homogenous and isotropic)
How big is the Universe
How big is the Universe
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Terrestrial Planets
Terrestrial Planets
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Jovian Planets
Jovian Planets
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Newborn stars emerging
from "eggs" — not the
barnyard variety — but
rather, dense, compact
pockets of interstellar
gas called evaporating
gaseous globules
(EGGs). Hubble found
the "EGGs,"
appropriately enough, in
the Eagle nebula, a
nearby star-forming
region
7,000 light-years
from Earth in the
constellation Serpents
One of the
nearest globular
star clusters,
called NGC 6397,
resembles a
treasure chest of
glittering jewels.
The cluster is
located
8,200
light-years
away
in the
constellation Ara.
Stellar swarm, M80
(NGC 6093), one of
the densest of the
147 known globular
star clusters in the
Milky Way Galaxy.
Located about
28,000 light-years
from Earth, M80
contains hundreds
of thousands of
stars, all held
together by their
mutual gravitational
attraction.
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Large Magellanic Cloud
165 000 LY
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Small Magellanic Cloud
195 000 LY
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The Sagittarius Dwarf Tidal Stream
Drawing Credit & Copyright: David Martinez-Delgado (MPIA) & Gabriel
Perez (IAC)
2003 September 30
Explanation:
Our
is actually still in the process of devouring its closest
This unfortunate neighbor, the
galaxy, is now seen to
be part of a larger
, a loose filament of stars,
gas, and possibly dark matter that entangles the
Speculation also holds that the Sagittarius Dwarf was once pulled
through the Milky Way disk very close to our Sun's current location.
NGC 1313,
(13.5 M light years)
a bright but rather isolated
galaxy classified as a barred spiral galaxy (although with very
short and irregular spiral arms). This galaxy collided with a
satellite galaxy, and the material at the bottom-right of this
picture are the remains of the satellite galaxy.
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Spiral galaxy NGC 4414
19.1 megaparsecs
(60 M LY)
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Galaxies tend to cluster into groups - the largest nearby
cluster is the Virgo cluster a concentration of several
hundred galaxies which dominates the galaxy groups
around it.
Our galaxy is just one of thousands that lie within 100
million light years.
All of these groups of galaxies are known as the Virgo
Super-cluster.
Number of galaxy groups within 100 million light years
= 200
Number of large galaxies within 100 million light years
= 2500
Number of dwarf galaxies within 100 million light years
= 25000
Number of stars within 100 million light years = 200
trillion
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The Virgo Cluster
The Virgo cluster is a massive cluster of galaxies which dominates
the Virgo super-cluster. There are roughly
2000 galaxies
in this
cluster (although ninety percent of them are dwarf galaxies). This
cluster has a diameter of approximately
15 million light years
.
The centre of the cluster showing the inner 4°x 4° region. Most of the brightest
objects in this picture are galaxies.
The elliptical galaxy in the centre is M87.
M 87
M 90
M 89
M 84
M 86
M87 from the Hubble Space Telescope
Hubble telescope was used to observe 19 galaxies out to
108 million
light-years
. The spiral galaxy NGC 4603, the most distant galaxy in
which Cepheid variables have been found. It is associated with the
Centaurus cluster, one of the most massive assemblages of galaxies
in the nearby universe.
A rare and spectacular head-on collision between two galaxies
appears in this Hubble telescope picture of the Cartwheel Galaxy,
located
500 million light-years
from Earth in the constellation
Sculptor.
The striking ring-like feature is a direct result of a smaller intruder
galaxy
Number of super-clusters in the visible universe = 10 million
Number of galaxy groups in the visible universe = 25 billion
Number of large galaxies in the visible universe = 100 billion
Number of dwarf galaxies in the visible universe = 10 trillion
Number of stars in the visible universe = 20 billion trillion
The Hubble Deep Field
Almost every object in this image is a galaxy typically lying
5 to 10 billion light years
away.
The galaxies revealed here are all shapes and colors, some are young and blue,
whereas others are old, red and dusty.
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The Visible Universe
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