Title: Drawing%20Constellations
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2- Goals
- Connect the dots" to form constellations from
stars - Recognize a few famous constellations and
asterisms and know the myths behind them - Ursa Major- The Big Bear
- Ursa Minor- The Little Bear
- Draco- The Dragon
- Cepheus-The King of Ethiopia
- Cassiopia-The Queen of Ethiopia
- Orion- The Hunter
- Big Dipper
- Little Dipper
- Recognize and Identify the brightest stars in
constellations - Polaris
- Rigel
- Betelgeuse
- Know the locations of modern and ancient pole
stars - Polaris
- Theban
3- As early as 5000 years ago, people began naming
patterns of stars, called constellations, in the
honor of mythological characters or great heroes. - Today, 88 constellations are recognized.
- They divide the sky into disjoint units.
- Every star in the sky is in one of these
constellations.
4- Astronomers label stars within a constellation
based on their apparent brightness, - brightest alpha a,
- second brightest beta b,
-
- Some of the brightest stars have actual names,
like Rigel Betelgeuse (both in the
constellation Orion)
5Ursa Major
Ursa Major, the Great Bear, is visible in the
Northern Hemisphere all year long.
6How to Find the Big Dipper
- Depending upon the season of the year, the Big
Dipper can be found high in the northern sky or
low in the northern sky. - Just remember the old saying spring up and fall
down. - On spring and summer evenings, the Big Dipper
shine highest in the sky. On autumn and winter
evenings, the Big Dipper lurks closest to the
horizon. - Given an unobstructed horizon, latitudes at and
north of Little Rock, Arkansas (35 degrees north)
can expect to see the Big Dipper at any hour of
the night for all days of the year. - As for the Little Dipper, it is circumpolar
always above the horizon as far south as the
tropic of Cancer (23.5 degrees north latitude).
7Circumpolar Constellations
8Ursa MajorCircumpolar Constellation
9Ursa Major
10Ursa Minor
- Ursa Minor, the Little Bear, is visible in the
Northern Hemisphere all year long. - Ursa Minor is mostly known for Polaris, the North
Star, which may be found at the end of the
handle.
11How to find Pole Star
12How to find Pole Star
13Ursa MinorCircumpolar Constellation
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15Draco
- Draco, the Dragon, used to hold special
significance as the location of the pole star,
but due to the Earth's precession, the pole has
shifted to Polaris in Ursa Minor. - Thuban, which forms the tail was the pole star
around 2600 B.C. when the ancient Egyptians were
building the pyramids.
16Draco
17Draco
- In ancient times, the Little Dipper formed the
wings of the constellation Draco the Dragon. - But when the seafaring Phoenicians met with the
Greek astronomer Thales around 600 B.C., they
showed him how to use the Little Dipper stars to
navigate. Thereby, Thales clipped Dracos wings,
to create a new constellation that gave Greek
sailors a new way to steer by the stars.
18Draco
- Draco's stars are not very bright, but five of
them have known planets. The head of the dragon
consists of four stars (Beta, Gamma, Nu and Xi
Draconis) in a trapezoid - From there, the dragon's body winds its way
through the sky, ending between the Big Dipper
and Little Dipper. From early to mid-October,
shooting stars known as the Draconids appear to
radiate from Draco's head.
19Circumpolar Constellations
20Circumpolar Constellations
21Circumpolar Constellations
22Circumpolar Constellations
23Circumpolar Constellations
24Circumpolar Constellations
25CepheusCircumpolar Constellation
26Circumpolar Constellations
27Cepheus
- The story behind it
- Cepheus was the King of Ethiopia. He married
Cassiopeia and they had a daughter Andromeda.
Cassiopeia was incredibly beautiful but immensely
vain. She was also proud of her daughter's
beauty. In fact she continually boasted that the
two of them were more beautiful than any of the
fifty sea nymphs who attended Poseidon's court. - These nymphs (the Nereids) complained to
Poseidon, who felt he had to defend his own
reputation. So he sent a flood to devastate
Cepheus' kingdom. The oracles told Cepheus that
in order to save his people he must sacrifice his
daughter to a great sea monster Andromeda was
tied to a rock along the coastline, dressed only
in her jewelry. The monster would be along in due
time to take his prize. - At that moment Perseus came flying by. He had
just killed the Gorgon Medusa and was carrying
the severed head back to Athene. To make a long
story short, he saved her then turned everyone
into stone by showing them the severed head. - Poseidon then put the stone frozen Cepheus and
Cassiopeia into the heavens, but with a twist he
made the vain Cassiopeia spin around on her
chair, spending half the year upside down. As for
Cepheus, Poseidon gave him a number of medium
sized stars that go to make his square face with
a pointed crown.
28CassiopeiaCircumpolar Constellation
29Circumpolar Constellations
30Saharan Starry Night
31Views of Orion from Tasmania (Australia) and
Iran (Asia)
32Orion Not a circumpolar constellation, but a
seasonal constellationBetelgeuse, the right arm
of Orion (or "armpit" as the name suggests),
glows with a dull red. Rigel, in the opposite
corner of the constellation, is blue and much
brighter.
33- Orion is a non- circumpolar constellations
- Orion is only visible in the fall and winter,
because in the spring and summer it would appear
during the day (and so it is drowned out by the
Sun).
34Orion
- Orion is the master of the winter skies. He lords
over the heavens from late fall to early spring,
with his hunting dog Sirius trailing at his feet.
- The story behind it (Orion holding an animal)
- Orion was known as the "dweller of the mountain",
and was famous for his prowess both as a hunter
and as a lover. But when he boasted that he would
eventually rid the earth of all the wild animals,
his doom may have been sealed. The Earth Goddess
sent the deadly scorpion to Orion to kill him.
Orion engaged the scorpion in battle but quickly
realized its armour was impervious to any
mortal's attack. Orion then jumped into the sea
and died. In his eternal hunting, Orion is
careful to keep well ahead of the scorpion. Orion
disappears over the horizon by the time Scorpio
rises in the east, as it becomes his turn to rule
the evening sky.
35Northern Hemisphere Constellations
Northern Circumpolar Constellations Northern Spring Constellation Northern Summer Constellations Northern Autumn Constellations Northern Winter Constellations
CassiopeiaCepheusDracoUrsa MajorUrsa Minor BootesCancerCraterHydraLeoVirgo AquilaCygnusHerculesLyraOphiuchusSagittariusScorpius AndromedaAquariusCapricornusPegasusPisces Canis MajorCetusEridanusGeminiOrionPerseusTaurus
36- On the left and in the middle Andromeda
- The Andromeda constellation is famous for
containing the Andromeda Nebula, the closest
galaxy to our Milky Way. - On the right The Fishes, Pisces
37Betelgeuse The Next Supernova?
What's in a Name Arabic for "shoulder of the giant". Could also mean "hand of al-jauza" where al-jauza is the Arabs' "Central One". Also known as the Martial Star.
Claim to Fame First star seen as a sphere instead of a point of light by the Hubble Space Telescope on March 3, 1995. 12th brightest star in the sky . Possibly will be the very next supernova in our galaxy.
Type of Star Orange-Red Supergiant (M2 Iab Spectral Class). 3300K surface temp.
How Far Away About 425 light years away
How Big 630 times the sun's radius. Would overfill the orbit of Jupiter if placed at the sun's position in the solar system
How Bright 60,000 times the sun's visual luminosity (absolute visual magnitude, Mv -7)
Where to View In the constellation of Orion
When to View Best viewed from the Northern hemisphere during December-March
- Betelgeuse The Next Supernova?
38Rigel - Bluish-white Supergiant
What's in a Name Arabic for "foot"
Claim to Fame One of the galaxy's brightest stars. Apparent visual magnitude 0.1
Type of Star Brilliant bluish-white Supergiant (B8 1a Spectral Type)
How Far Away 775 light years away
How Big 70 times the sun's diameter
How Bright 40,000 times the sun's luminosity (Absolute visual magnitude - 6.8)
Where to View Brightest star in Orion (Star Map).
When to View December through March from Northern middle latitudes
39- On the left The Hunter - Orion
- In the middle Name The Bull - Taurus
- On the right Name The Greater Dog - Canis Major
40- On the left The Lion - Leo
- In the middle The Herdsman - Böötes
- On the right The Virgin - Virgo
41Summer
- On the left The Crab - Cancer
- In the middle The Scorpion - Scorpio
- On the right The Archer - Sagittarius
42Ecliptic Constellations Zodiac Signs
- A band of 12 constellations around the sky
entered on the ecliptic (apparent path of the sun
on the earth as the earth revolves around it). - Aries, Leo, Sagittarius, Taurus, Virgo,
Capricorn, Gemini, Libra, Aquarius, Cancer,
Scorpio, and Pisces.
43Ecliptic Constellations
44Hindu Calendar Rashi
45The Constellations, using H. A. Rey's Scheme
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47Andromeda Antlia Apus Aquarius
Aquila Ara Aries Auriga
Boötes Caelum Camelopardalis Cancer
Canes Venatici Canis Major Canis Minor Capricornus
Carina Cassiopeia Centaurus Cepheus
Cetus Chamaeleon Circinus Columba
Coma Berenices Corona Australis Corona Borealis Corvus
Crater Crux Cygnus Delphinus
Dorado Draco Equuleus Eridanus
Fornax Gemini Grus Hercules
Horologium Hydra Hydrus Indus
Lacerta Leo Leo Minor Lepus
Libra Lupus Lynx Lyra
Mensa Microscopium Monoceros Musca
Norma Octans Ophiuchus Orion
Pavo Pegasus Perseus Phoenix
Pictor Pisces Piscis Austrinus Puppis
Pyxis Reticulum Sagitta Sagittarius
Scorpius Sculptor Scutum Serpens
Sextans Taurus Telescopium Triangulum
Triangulum Australe Tucana Ursa Major Ursa Minor
Vela Virgo Volans Vulpecula
48Brightest Stars and Their Constellations
http//www.enchantedlearning.com/subjects/astronom
y/stars/bright.shtml
http//www.astro.wisc.edu/dolan/constellations/ex
tra/brightest.html
49The Dome of the SkyDefinitions in your local sky
50To Polaris
Angular size of moon ½ o
Angular distance between the pointer stars 5o
51Latitude and Longitude
Beavercreek, OH Latitude 39.73 N, Longitude
84.06 W
52- Different sets of constellations are visible in
northern and southern skies.
The Altitude of the celestial pole (Polaris)
your latitude
53Counter-Clockwise Rotation
Clockwise Rotation
Northern Hemisphere
Southern Hemisphere
The Altitude of the celestial pole (Polaris)
your latitude
54Right Ascension and Declination
- Right Ascension (RA) Analogous to longitude, but
on the celestial sphere. - It is the east-west angle between the vernal
equinox and a location on the celestial sphere. - Declination (dec) Analogous to latitude, but on
the celestial sphere. - It is the north-south angle between the celestial
equator and a location on the celestial sphere.
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56Units of R.A. 360o 24h ? 15o/h
57Azimuth and Altitude are observer centric.