1. Celestial Objects and Constellations

2. Dwarf Planets
Dwarf planets orbit around the Sun, but do not dominate their orbit
There are 5 recognized dwarf planets:
Ceres ***
Pluto ***
Haumea
Makemake
Eris
…maybe more…

3. Asteroid Belt
Located between Mars and Jupiter and contain thousands of asteroids
Asteroids: small celestial objects made of rock and metal that are less than 1000 km across
Occasionally run into Earth and other planets

4. Comets
Dirty snowballs made of ice, gas, dust and sometimes tiny traces of organic material

6. Comets Parts of a comet:
Nucleus: Irregularly shaped object made of rock, dust, ice and frozen gases
Coma: A temporary atmosphere around the nucleus
Tails: The dust tail reflects the Sun’s light and may be influenced by the movement of the comet. The Ion tail is created by solar wind reacting with material on the comet to produce a tail that is directed away from the comet

7. Meteoroid to Meteor to Meteorite

8. Meteoroid to Meteor to Meteorite
Meteoroid: A lump of rock or metal smaller than an asteroid travelling through space
Meteor: A meteoroid that has become trapped in Earth’s gravity. Friction from Earth’s atmosphere causes the meteor to glow.
Meteorite: A meteor that has enough mass to strike the surface of Earth before burning up

12. Constellations
Prominent luminous objects that form consistent patterns in the night sky.
The IAU (International Astronomical Union) recognizes 88 constellations, but only 20 are truly prominent and may be easily identified

13. Ursa Major (Big Dipper)
Made up of 7 stars
Imagined by different cultures to represent a bear. The ‘Dipper” is described in different cultures because it points to the North star.

14. Ursa Major (Big Dipper)
Made up of 7 stars
Imagined by different cultures to represent a bear. The ‘Dipper” is described in different cultures because it points to the North star.

16. Ursa Minor (Little Dipper)
Also made up of 7 stars
Discovered by Ptolemy
Contains Polaris at its “handle”

17. Ursa major and Ursa Minor
If one extends the last two stars in the “bowl” of Ursa Major, it will connect to Polaris (in Ursa Minor)

18. Polaris AKA North Star AKA Pole Star
The brightest star in the Ursa Minor constellation.
430 light years from Earth
Actually a multiple star system

19. Orion: The Hunter Can be seen from November to February
Easily recognizable
Used to locate other stars

22. Orion: The Hunter
Orion’s belt may be used to locate Sirius (the brightest star in the night sky)

24. Canis Major – “Greater Dog”
Dog star constellation
Contains Sirius (brightest star in the sky) and VY Canis Majoris (Largest known star)

27. Homework
Read 8.6 and try questions 1-7