About constellation

2.  The stars forming a group that has a
recognisable shape or a group of stars which
are arranged in pattern resembling some
recognizable figure is called a constellation .
 Constellation can compared to asterism but in
asterism is grouping of stars that does not
make a constellation .

3. The origins of the earliest constellations likely go back to prehistory. People
used them to relate stories of their beliefs, experiences, creation, or mythology.
Different cultures and countries adopted their own constellations, some of
which lasted into the early 20th century before today's constellations were
internationally recognized. The recognition of constellations has changed
significantly over time. Many have changed in size or shape. Some became
popular, only to drop into obscurity. Others were limited to a single culture or
nation.
The 48 traditional Western constellations are Greek. They are given in Aratus'
work Phenomena and Ptolemy's Almagest, though their origin probably
predates these works by several centuries. Constellations in the far southern
sky were added from the 15th century until the mid-18th century when
European explorers began travelling to the Southern Hemisphere. Twelve
ancient constellations belong to the zodiac (straddling the ecliptic, which the
Sun, Moon, and planets all traverse). The origins of the zodiac remain
historically uncertain; its astrological divisions became prominent c. 400 BC in
Babylonian or Chaldean astronomy.
In 1922, the International Astronomical Union (IAU) formally accepted the
modern list of 88 constellations, and in 1928 adopted official constellation
boundaries that together cover the entire celestial sphere

4.  There are about 88 constellation that we know
in the solar system and are visible to us with
naked eyes but some of them have very less
shining stars therefore it is suggested to see
them with the help telescope . Well known
constellations are :-
 Oroin
 Ursa Major (Saptrishi)
 Ursa Minor

5.  Cassiopeia
 Leo Major
 Great Bear
 Some of major stars are :-
 Pole star
 Sirius
 NOTE:-
 The word constellation comes from the late
latin term constellatio which means set of stars.

7. Ursa major
•It is also known as the
great bear,the big dipper
and the saptarishi .
•Ursa Major contains
seven stars making the
pattern of a plough.
•A line drawn through
the pointers of the
plough leads to the pole
star or the polaris .
(Dhruv Tara)
•It is visible during the
summer season.

8. Dubhe
Merak
Phecda
Megrez
Alioth
Mizar
Alkaid

10. ORION
It is one of the
magnificent
constellation in the
sky .
It has seven bright
stars.
This constellation
is visible durinng
the winter in the
northern
hemisphere .

11. Four of these appear to be arranged in the
form of a quadrilateral and the other three on
one corner of form a straight line in middle .
The arrangement of the stars in this
constellation resembles to a hunter with a belt
and a sword.
The star Sirius which is the brightest star in
the sky is located close to orion .
To locate Sirius , imagine a straight line
passing through the three middle stars of
orion .

12. Casssiopeia
•Casssiopeia is
another prominent
constellation in the
northen sky .
•It is visible during
winter in the early
part of the night .
•It looks like a
distorted letter W or
M .

14.  Saptarishi has been associated with seven well
known ancient Indian sages or rishis . According to
ancient mythology , the seven sages who formed the
saptarishi , preserve the eternal knowledge of Vedas
and explain it to people in every new age .
 The polar star and the ursa major are not completely
or not at all visible from the southern hemisphere .
 A constellation does not have only 5-10 stars . It has
a large number of stars . However , we can see only
the bright stars inn the constellation with our naked
eyes . All the stars which make up a constellation are
not at the same distance , they are just in the same line
of sight in the sky.

15. Asterism Not Considered True Constellation
An asterism is a pattern of stars that are widely
recognized and contained within an official constellation
but is not counted as a true constellation in itself. The
Big Dipper, for instance, is a famous asterism but the
seven stars in this arrangement of stars represent less
than half of the whole constellation known as Ursa
Major. Another famous asterism is the three stars in a
row which form Orion’s belt.

16. Rotation Of Constellations A Matter of Perspective
The direction in which the constellations appear to rotate in
the night sky is truly a matter of perspective, and is
determined by the Earth’s rotation, as well as the direction in
which an observer is facing. Looking north, the
constellations appear to rotate counter clockwise around a
fixed point in the night sky known as the north celestial pole,
which is located near the north star Polaris. This is because
the Earth spinning from West to East means the ground
beneath you is rotating to your right, while above you the
stars appear to follow an East to West direction (right to left)
just like the Sun, Moon, and planets. If you face south,
however, the stars would seem to revolve in a clockwise
direction (left to right); while a person facing east would see
the stars coming up in front of them and setting behind
them. Likewise, a west facing observer will see the stars
appearing to rise behind them before setting to their front

17. Knowledge Of Constellations Came From Early Cultures
The Greeks knowledge of the constellations stretches way
back in time at least to the 8th century BC when Homer
made the earliest known Greek reference to the
constellations Boötes, Orion, and Ursa Major in his epic
poem the Illiad and the Odyssey. Nevertheless, much of the
Greek’s initial knowledge of the constellations came to them
from the Ancient Egyptians, who likely inherited their
understanding from Ancient Babylon and Sumeria before
them. In fact, at least 30 modern constellations can be shown
to date back to at around the Late Bronze Age (1650-1050
BC), with references to some of the constellations found in
Mesopotamian clay writing tablets and Babylonian star
constellation catalogs dating back to the 3rd millennium
BCE. There are also references to be found in the Hebrew
Bible, and Biblical texts. Orion is perhaps the most
distinctive of all the constellations, and an amazing
discovery was made in 1972 at the Ach valley in Germany
after an image of Orion was found carved into a piece of
mammoth ivory more than 32,000 years old.