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The Universe…




…is space and everything in it.
Galaxies
A galaxy is a cluster of
 stars, gas, and dust that
 are held together by
 gravity.

 Thereare three main
 types of galaxies:
   Irregular
   Elliptical

   Spiral
Types of Galaxies – Irregular…

 Some  galaxies do
 not have definable,
 regular shapes and
 are known as
 irregular galaxies.

 They contain young
 stars, dust, and
 gas.
Types of Galaxies – Elliptical...
Ellipticalgalaxies look like
  flattened balls.
These   galaxies contain billions
  of stars, but have little gas and
  dust between the stars.
Because    of the lack of gas and
dust, new stars cannot form in
most elliptical galaxies, and so they
contain only old stars.

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THE UNIVERSETHE UNIVERSE
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The document provides an overview of the size and contents of the universe. It begins by explaining that the universe includes all physical matter and energy, from atoms to galaxies. It then notes that the tour will focus on the part of the universe outside Earth. The document goes on to summarize how human understanding of the universe's size has expanded over time, from only a few thousand light years across to immensely larger. It lists some of the key components that make up the universe, such as matter, energy, planets, stars, and more.

The moon
The moonThe moon
The moon

The moon revolves around Earth once every 27 days, keeping the same side facing Earth. It reflects sunlight and its illuminated half changes shape in a cycle from new moon to first quarter to full moon to third quarter over 291⁄2 days. The moon is the closest celestial object to Earth at 384,000 km away. It has many impact craters and temperature extremes ranging from 127°C during the day to -173°C at night. Telescopes allow observation of details on the moon's surface.

Space science powerpoint
Space science powerpointSpace science powerpoint
Space science powerpoint

The document defines and describes various celestial objects in our solar system including: - Rotation is spinning on an axis, while revolution is the path planets make around the sun. - The inner planets are Mercury, Venus, Earth and Mars which are rocky and smaller. The outer planets are the large gaseous planets of Jupiter, Saturn, Uranus and Neptune past the asteroid belt. - Other objects include asteroids in the asteroid belt between Mars and Jupiter, comets that travel in elliptical paths around the sun, and meteors that appear as shooting stars as they burn up in Earth's atmosphere.

Types of Galaxies –Spiral…
Spiral   galaxies consist of a
flat, rotating disk with stars, gas,
and dust and a central
concentration of stars, known
as the bulge. The bulge is
surrounded by a much fainter
halo of stars.

Contains   middle aged stars
Types of Galaxies – Barred Spiral…

Our   Milky Way galaxy has
recently (in the 1990s) been
confirmed to be a type of
spiral galaxy known as a
barred spiral galaxy.

Our  Sun is located at the
edge of the Milky Way
galaxy.
Nebulae (plural for Nebula)
 Stellar Nebula- A
  gigantic cloud of gas and
  dust from which stars are
  made; sometimes called
  a “Stellar Nursery”

 Planetary   Nebula- When
  a star runs out of fuel to
  burn, its outer layers of
  gas are blown outward in
  the shape of a ring.
Stars
A   star contains hydrogen gas that forms helium
  through a process known as nuclear fusion. Stars
  form when gravity pulls together gas and dust
  from stellar nebula.

 Itreleases enormous amounts of energy which
  causes the star to become very hot and glow.

 Vary   in mass, size, and temperature

 Held   together by gravity.

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Stellar evolution ppt
Stellar evolution pptStellar evolution ppt
Stellar evolution ppt

This document provides a summary of stellar evolution from the birth of stars to their death. It discusses how stars are formed inside nebulae from collapsing gas clouds. As stars age, they progress through different stages such as protostars, T-Tauri stars, and red giants. More massive stars may die in supernova explosions, leaving behind neutron stars or black holes. Lower mass stars end as white dwarfs. The document also describes different types of nebulae and compact objects like neutron stars and black holes.

astronomysciencephysics
Stars
StarsStars
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It is a slide showing the general information as well as some interesting information about stars that a student needs for his school.

formation of starsdeath of starsetc.
A Star is Born…
A   star is made up of a large amount of gas,
  in a relatively small volume.
A   stellar nebula, on the other hand, is a
  large amount of gas and dust,
  spread out in an immense
  volume.
 All
    stars begin their lives as parts of stellar
  nebulas.
A Star is Born…

 Gravitycan pull some of the gas and dust
 in a nebula together.
 The contracting cloud is
  then called a protostar.

A star is born when the contracting gas
 and dust become so hot that nuclear
 fusion begins.
Lifetimes of Stars…
 Beforethey can tell how old a star is,
 astronomers must determine its mass.

 Medium  mass stars, such as the Sun, exist
 for about 10 billion years.

 These are known as
  main sequence stars.
Lifetimes of Stars…

 Starswith more mass have shorter lives
 than those with less mass.

 Small stars use up their fuel more slowly
 than large stars, so they have much longer
 lives, about 200 billion years.

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Stars are giant balls of gas that produce light and heat through nuclear fusion at their cores. They vary greatly in size, from dwarf stars like our Sun to massive supergiant stars over 200 times the Sun's diameter. Stars end their lives in different ways depending on their mass - smaller stars become white dwarfs, while larger stars explode as supernovae or collapse into neutron stars and other compact objects.

Stars and Constellations
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Information for Primary School students on stars and constellations. This PowerPoint uses some slides from http://www.slideshare.net/winga1sm/star-powerpoint-3308182 and the rest has been created by me.

Our universe
Our universeOur universe
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The document discusses key facts about our planet Earth. It begins by providing context about our solar system and universe. It then explains that Earth is the third planet from the sun and the only planet that supports life. The document goes on to describe how Earth formed from a hot cloud of gases and cooled over millions of years, developing a crust, mantle and core similar to an egg. Volcanoes are mentioned as openings where molten material from the core is forced out of the crust.

Lifetimes of Stars…
Stars form in a stellar
nebula, from collapsing
clouds of interstellar gas
and dust. This is called a
protostar.                     The rest of the life
                               cycle depends on
                               the mass of the
When a star runs out of        star.
fuel, it will become a white
dwarf, neutron star, or
black hole.
Main Sequence Stars…
 Main
     Sequence is the stage in which stars
 spend the majority of their lifetime.
 Small
      and medium stars first
 become red giants.
 Theirouter layers expand during the red
 giant phase.

 Eventually, the outer parts grow bigger still
 and drift out into space.
Main Sequence Stars...

 Theblue, white, hot core is left
  behind causing a white dwarf.


 When there is no more energy, it
 becomes a black dwarf. It is the remaining
 burnt-out cinder left, as the star goes out.
A dying giant, or supergiant star, can
 suddenly explode. Within hours, the star
 blazes millions of times brighter.




 The   explosion is called a supernova.

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The Moon
The MoonThe Moon
The Moon

The Moon is Earth's only natural satellite. It has no atmosphere and its surface is marked by craters and dust. The same side always faces Earth. The Moon's diameter is about one quarter that of Earth and it has lower gravity and density than Earth. Temperatures vary greatly from 130°C during the day to -110°C at night. Large flat plains called maria cover parts of the near side, formed by ancient lava flows. Craters and long valleys called rilles are also features of its surface. The Moon orbits Earth about every 27 days in a cycle linked to eclipses.

sciencemooncollege presentation
The Stars And The Galaxies In The Universe 2 L
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This powerpoint slidesare from form 3 sallabus and it is about stars and galaxies. Students are allowed to view and upload their ideas of stars and galaxies.

Galaxy
Galaxy Galaxy
Galaxy

Galaxies come in different sizes and types. They range from dwarfs with a few billion stars to giants with over 100 trillion stars. Galaxies are classified into three main types - ellipticals, spirals, and irregulars. The Hubble sequence further categorizes galaxies based on their visual structure into ellipticals, spirals, barred spirals, and lenticular galaxies. Spiral galaxies have a central bulge and spiral arms, while ellipticals are spherical or ellipsoidal. Interacting galaxies can trigger new star formation when their gas and dust interact during collisions.

environmentgeographyastronomy
Neutron Stars…
 After
      a star explodes, some material
 from the star is left behind. This
 material may become part of a
 planetary nebula.
 Thecore will compress
  and form a neutron star.
 Neutron  stars are even
  smaller and more dense
than white dwarfs.
Black Holes…
 Themost massive stars may have more
 than 40 times the mass of the Sun. One
 might have more than five times the
 mass of the Sun left, after it becomes a
 supernova.

 The gravity of this mass is so strong that
 the gas is pulled inward, packing it into a
 smaller and smaller space. These
 massive stars become black holes when
 they die.

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Galaxies and stars

  • 1. The Universe… …is space and everything in it.
  • 2. Galaxies A galaxy is a cluster of stars, gas, and dust that are held together by gravity.  Thereare three main types of galaxies:  Irregular  Elliptical  Spiral
  • 3. Types of Galaxies – Irregular…  Some galaxies do not have definable, regular shapes and are known as irregular galaxies.  They contain young stars, dust, and gas.
  • 4. Types of Galaxies – Elliptical... Ellipticalgalaxies look like flattened balls. These galaxies contain billions of stars, but have little gas and dust between the stars. Because of the lack of gas and dust, new stars cannot form in most elliptical galaxies, and so they contain only old stars.
  • 5. Types of Galaxies –Spiral… Spiral galaxies consist of a flat, rotating disk with stars, gas, and dust and a central concentration of stars, known as the bulge. The bulge is surrounded by a much fainter halo of stars. Contains middle aged stars
  • 6. Types of Galaxies – Barred Spiral… Our Milky Way galaxy has recently (in the 1990s) been confirmed to be a type of spiral galaxy known as a barred spiral galaxy. Our Sun is located at the edge of the Milky Way galaxy.
  • 7. Nebulae (plural for Nebula)  Stellar Nebula- A gigantic cloud of gas and dust from which stars are made; sometimes called a “Stellar Nursery”  Planetary Nebula- When a star runs out of fuel to burn, its outer layers of gas are blown outward in the shape of a ring.
  • 8. Stars A star contains hydrogen gas that forms helium through a process known as nuclear fusion. Stars form when gravity pulls together gas and dust from stellar nebula.  Itreleases enormous amounts of energy which causes the star to become very hot and glow.  Vary in mass, size, and temperature  Held together by gravity.
  • 9. A Star is Born… A star is made up of a large amount of gas, in a relatively small volume. A stellar nebula, on the other hand, is a large amount of gas and dust, spread out in an immense volume.  All stars begin their lives as parts of stellar nebulas.
  • 10. A Star is Born…  Gravitycan pull some of the gas and dust in a nebula together.  The contracting cloud is then called a protostar. A star is born when the contracting gas and dust become so hot that nuclear fusion begins.
  • 11. Lifetimes of Stars…  Beforethey can tell how old a star is, astronomers must determine its mass.  Medium mass stars, such as the Sun, exist for about 10 billion years.  These are known as main sequence stars.
  • 12. Lifetimes of Stars…  Starswith more mass have shorter lives than those with less mass.  Small stars use up their fuel more slowly than large stars, so they have much longer lives, about 200 billion years.
  • 13. Lifetimes of Stars… Stars form in a stellar nebula, from collapsing clouds of interstellar gas and dust. This is called a protostar. The rest of the life cycle depends on the mass of the When a star runs out of star. fuel, it will become a white dwarf, neutron star, or black hole.
  • 14. Main Sequence Stars…  Main Sequence is the stage in which stars spend the majority of their lifetime.  Small and medium stars first become red giants.  Theirouter layers expand during the red giant phase.  Eventually, the outer parts grow bigger still and drift out into space.
  • 15. Main Sequence Stars...  Theblue, white, hot core is left behind causing a white dwarf.  When there is no more energy, it becomes a black dwarf. It is the remaining burnt-out cinder left, as the star goes out.
  • 16. A dying giant, or supergiant star, can suddenly explode. Within hours, the star blazes millions of times brighter.  The explosion is called a supernova.
  • 17. Neutron Stars…  After a star explodes, some material from the star is left behind. This material may become part of a planetary nebula.  Thecore will compress and form a neutron star.  Neutron stars are even smaller and more dense than white dwarfs.
  • 18. Black Holes…  Themost massive stars may have more than 40 times the mass of the Sun. One might have more than five times the mass of the Sun left, after it becomes a supernova.  The gravity of this mass is so strong that the gas is pulled inward, packing it into a smaller and smaller space. These massive stars become black holes when they die.

Editor's Notes

  1. http://commons.wikimedia.org/wiki/File:2MASX_J00482185-2507365_by_HST.jpg
  2. http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level1/galaxies.html
  3. http://commons.wikimedia.org/wiki/File:I_Zwicky_18a.jpg
  4. http://commons.wikimedia.org/wiki/File:I_Zwicky_18a.jpg
  5. http://commons.wikimedia.org/wiki/File:2MASX_J00482185-2507365_by_HST.jpg
  6. http://www.nasa.gov/mission_pages/hubble/science/hstimg_ngc6217.html
  7. http://www.nasa.gov/multimedia/imagegallery/image_feature_768.html http://www.nasa.gov/multimedia/imagegallery/image_feature_77.html
  8. http://www.nasa.gov/mission_pages/spitzer/multimedia/spitzer20091123-b.html
  9. http://www.nasa.gov/multimedia/imagegallery/image_feature_21.html
  10. http://www.nasa.gov/audience/foreducators/topnav/materials/listbytype/Lifecycle_of_a_Star.html
  11. http://www.nasa.gov/multimedia/imagegallery/image_feature_468.html
  12. http://www.nasa.gov/multimedia/imagegallery/image_feature_219.html
  13. http://commons.wikimedia.org/wiki/File:M51_CHANDRA2.jpg