An activity to explore your place in the universe. Galactic Address An activity to explore your place in the universe.

Our Universe Everything that exists anywhere; includes planets, stars, galaxies, and black holes Age- between 12 and 15 billion years old (~ 13.7BYA) In open space, away from stars, the temperature is -454 degrees F, that is 3 degrees away from absolute zero.

Origin of the Universe Most widely accepted scientific explanation is The Big Bang Theory, which continues to be tested with each new discovery about the universe. The whole universe was originally packed into a dense sphere of hydrogen, not much larger than the sun is today. About 14 billion years ago the sphere exploded, forming an expanding cloud that moved outward, all of the elements of the Periodic Table were formed at this time through star death.

Origin of the Universe… continued Areas of the cloud eventually condensed to form billions of galaxies. In 1929, Edwin Hubble found evidence showing that the universe is still expanding. In 1978, Penzias and Wilson found leftover energy (Cosmic Background Radiation) from The Big Bang and won the Nobel Prize in physics.

Conceptual pic of spacetime expanding like a balloon with galaxies and all matter being moved along the fabric of spacetime.

10^2s = 100s 3x10^5 years = 300K years 10^9 = 1,000,000,000 (1B years) 12x10^9 years = 12,000,000,000 (12B years)

Used to show a current view of the galaxies viewed through the Hubble deep field. Galaxies are moving away from each other faster and faster.

Stars A star is a massive, luminous sphere of plasma held together by its own gravity. The nearest star to Earth is the Sun, which is the source of most of the planet's energy. Some other stars are visible from Earth during the night, appearing as a multitude of fixed luminous points due to their immense distance. Historically, the most prominent stars were grouped into constellations and asterisms, and the brightest stars gained proper names. Extensive catalogues of stars have been assembled by astronomers, which provide standardized star designations. For at least a portion of its life, a star shines due to thermonuclear fusion of hydrogen into helium in its core, releasing energy that traverses the star's interior and then radiates into outer space. Once the hydrogen in the core of a star is nearly exhausted, almost all naturally occurring elements heavier than helium are created by stellar nucleosynthesis during the star's lifetime and, for some stars, by supernova nucleosynthesis when it explodes.

Star Systems – A Triple System This is a picture of a triple star system. Most stars do not exist individually like in our solar system. They exist at least with another star in a binary system. This is one of the ways that our solar system is unique. Since we don’t live in a star system, we report our star system as being in the Orion Arm or Spur of our galaxy. An international team of astronomers using the National Science Foundation’s Green Bank Telescope have discovered a unique stellar system consisting of two white dwarf stars and a superdense pulsar that may provide a key clue for resolving one of the principal outstanding problems of fundamental physics – the true nature of gravity.

Galaxies A galaxy is a large scale group of stars, gas, dust, and planets bound together by gravitational attraction. Galaxies contain millions to billions of stars and there are billions of galaxies in the universe, millions of light-years apart. With a telescope, a galaxy is a fuzzy light source, while a star is a pinpoint of light We call our star the Sun.

Three main types of galaxies: Galaxies…continued Three main types of galaxies: Spiral galaxies (75 %)-central lens-shaped nucleus with spiral arms (containing gas and dust) that come out from opposite sides of the nucleus and trail behind as the galaxy rotates. Ex. Milky Way, Andromeda Galaxy Elliptical galaxies (20%)-nearly spherical to lens-shaped, with most of the stars close to the center. Irregular galaxies (5%)-smaller, fainter, and less common than the other two types. Ex. Magellanic Clouds

Spiral Galaxy – Milky Way We are located in the Orion Arm or Orion Spur (Star System)

Elliptical Galaxy – M87 This galaxy is not as “flat” or planar as a spiral galaxy. The center bulges more and stars form an elliptical shape. There is little gas and dust in these types of galaxies. M87 is a large galaxy especially for an elliptical.

Irregular Galaxy – The Bird A 3 Galaxy Collision! The galaxy ESO 593-IG 008, or IRAS 19115-2124, was previously merely known as an interacting pair of galaxies at a distance of 650 million light-years. But surprises were revealed by observations made with the NACO instrument attached to ESO's VLT, which peered through the all-pervasive dust clouds, using adaptive optics to resolve the finest details. Subsequent optical spectroscopy with the new Southern African Large Telescope, and archive mid-infrared data from the NASA Spitzer space observatory, confirmed the separate nature of the 'head', but also added further surprises. The 'head' and major parts of the 'Bird' are moving apart at more than 400 km/s (1.4 million km/h!). Observing such high velocities is very rare in merging galaxies. Also, the 'head' appears to be the major source of infrared luminosity in the system, though it is the smallest of the three galaxies. "It seems that NACO has caught the action right at the time of the first high-speed fly-by of the 'head' galaxy through the system consisting of the other two galaxies," says Seppo Mattila, member of the discovery team. "These two galaxies must have met earlier, probably a couple of hundred million years ago." The 'head' is forming stars violently, at a rate of nearly 200 solar masses per year, while the other two galaxies appear to be at a more

Galactic Clusters In a galaxy, clusters of stars form where there was a higher density of gasses (nebulae). Galaxies form in the same way; where there were more dense deposits of gasses and dust. Our Milky Way Galaxy is about 100,000 light years across.

Galactic Clusters – Local Group

Galactic Super Cluster - Virgo Many of the super clusters are where our familiar constellations are located.

From Earth to the Universe

Your Galactic Address It is now time to take a quick tour before you work to find your place in the universe, your galactic address…due at the end of class period tomorrow. Examine the Milky Way Galaxy at different scales.

Address your envelope Use your notes to complete your entire galactic address. Add the Universe at the bottom since we’re all members of the same Universe! Example of a correct galactic address: Michael Cappo Desk 1 MTMS Monroe NJ 08831 USA Earth The Sun The Orion Spur Milky Way Galaxy The Local Group Virgo Super Cluster The Universe