Constellations

1
Constellations
http//www.hope.co.nz/projects/stars/stars_ss_dx_o
rg.jpg
2
What is a constellation?

• A constellation is a group of stars that are
  connected together to form a figure or picture.
• The term is also used to mean any group of stars
  visibly related to each other
• Considered as a fixed configuration or pattern in
  a particular culture.

3

• The International Astronomical Union (IAU)
  divides the sky into 88 official constellations
  with exact boundaries, so that every direction or
  place in the sky belongs within one
  constellation.

4

• Northern hemisphere- constellations based upon
  the constellations of the ancient Greek
  tradition, containing the signs of the zodiac

http//www.fas.org/irp/imint/docs/rst/Sect20/map3
.jpg
5
http//www.astropix.com/IMAGES/C_SPRING/BIGDIP.JPG

• A star pattern may be widely known but may not be
  recognized by the International Astronomical
  Union such a pattern of stars is called an
  asterism.
• An example is the grouping called the Big Dipper.

6

• The grouping of stars into constellations is
  essentially arbitrary and random
• Different cultures have had different
  constellations, although a few of the more
  obvious ones tend to recur frequently, e.g.,
  Orion and Scorpius.

7

• In space, most of the stars we see have little or
  no relation to one another, but can appear to be
  grouped in the night sky.
• The stars in a constellation rarely have any
  astrophysical relationship to each other they
  just happen to appear close together in the sky
  as viewed from Earth they typically lie many
  light-years apart in space. One exception to this
  is the Ursa Major.

8
http//joemorris.mystarband.net/images/Orion20Con
stellation.jpg

• Some well-known constellations contain striking
  and familiar patterns of bright stars.
• Examples
• Orion (containing a figure of a hunter)
• Leo (containing bright stars outlining the form
  of a lion)
• Scorpius (a scorpion)
• Crux (a cross).

9
http//www.astropix.com/HTML/WIDE/CONST16.HTM
10
http//www.astropix.com/HTML/WIDE/CONST03.HTM
http//www.astropix.com/HTML/WIDE/CONST09.HTM
11
http//www.astropix.com/HTML/WIDE/CONST10.HTM
12
http//www.astropix.com/HTML/WIDE/CONST14.HTM
13
http//www.astropix.com/HTML/WIDE/CONST17.HTM