1. The Universe

2. Cosmology
the branch of astronomy that deals with the origin, large-scale properties, and the evolution of the observable universe

3. The Universe
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
Can you think of something in the universe that cannot be seen, but its effects on other things can be detected?

4. “Big Bang” Theory
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
Misconception Alert:
Describing this theory as
the “Big Bang” is a misnomer
because there really was not
an explosion, just a release of
energy

5. Edwin Hubble
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:

6. Arno Penzias & Robert Wilson
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:

7. Galaxy
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?

8. 3 Types of Galaxies 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
Spiral
have arms of stars, gas , and dust that curve away from the center of the galaxy in a spiral pattern
Ex. – Milky Way
The process of galaxies colliding to create a larger galaxy is known
as “galactic cannibalism.”
Images taken from:

9. Why is it not possible to see all constellations at once?
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?

10. Solar System
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:

11. Planet 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”

12. Asteroids 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:

13. Meteoroid, Meteor, Meteorite
Meteoroid (asteroid)
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 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
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?

14. Comet
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:

15. Satellite 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

16. Telescope Types: a device that gathers electromagnetic radiation
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

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

18. Astronomical Unit (AU)
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
The Earth animation is not rotating in the correct direction;
it should be rotating from west to east
150 million km
(93 million mi.)

19. Light Year
the distance that light travels in one year in a vacuum, which is about 9.5 trillion kilometers (6 trillion miles)
The Milky Way Galaxy is about 100,000 light years in diameter
the speed at which light travels this distance is about 300,000 km/sec (186,000 mi/sec)
The second closest star to the Earth is a little over four light years away. How far away (in miles) is the star?

20. If one parsec equals 206, 265 AU, how many miles is it equal to?
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?

21. Find the Distance to HT Cas Using Parallax
the apparent shift in position of an object when viewed from different locations
used by astronomers to measure distance
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?
Parallax Simulation
Parallax Simulation – 1
Parallax Simulation - 2
Find the Distance to HT Cas Using Parallax