* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download May
Formation and evolution of the Solar System wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
Modified Newtonian dynamics wikipedia , lookup
Spitzer Space Telescope wikipedia , lookup
History of supernova observation wikipedia , lookup
Constellation wikipedia , lookup
Auriga (constellation) wikipedia , lookup
Corona Borealis wikipedia , lookup
Canis Minor wikipedia , lookup
Future of an expanding universe wikipedia , lookup
Stellar kinematics wikipedia , lookup
Globular cluster wikipedia , lookup
Observational astronomy wikipedia , lookup
Type II supernova wikipedia , lookup
Timeline of astronomy wikipedia , lookup
Canis Major wikipedia , lookup
High-velocity cloud wikipedia , lookup
Cassiopeia (constellation) wikipedia , lookup
H II region wikipedia , lookup
Andromeda Galaxy wikipedia , lookup
Star formation wikipedia , lookup
Cygnus (constellation) wikipedia , lookup
Aries (constellation) wikipedia , lookup
Corona Australis wikipedia , lookup
Cosmic distance ladder wikipedia , lookup
Aquarius (constellation) wikipedia , lookup
Perseus (constellation) wikipedia , lookup
Coma Berenices wikipedia , lookup
MAY 2008 VIEWING LIST Object Type 14” Scopes Saturn M101* M108** M65** M66** NGC3628** NGC4565* NGC4656 M64** M53* M3 M5 (See Notes) Gal Gal Gal Gal Gal Gal Gal Gal GC GC GC Size 22’ 9’ 8’ 8’ 14’ 16’ 19 9’ 13’ 18’ 12’ 4” Refractor Iota Cancri DS Cor Caroli DS Y Canum Venaticorum Carbon Star Distance Coordinates LY LY LY LY LY LY LY LY LY LY LY 14h 03’ 11h 12’ 11h 19’ 11h 20’ 11h 20’ 12h 36’ 12h 44’ 12h 57’ 13h 13’ 13h 42’ 15h 19’ +54 21’ +55 40’ +13 05’ +12 59’ +13 36’ +25 59’ +32 10’ +21 41’ +18 10’ +28 23’ +02 06’ 300 LY 110 LY 711 LY 08h 47’ 12h 56’ 12h 45’ +28 46’ +38 19’ +4526’ 27,000,000 45,000,000 35,000,000 35,000,000 35,000,000 32,000,000 23,500,000 19,000,000 58,000 34,000 25,000 Abbreviations: MS = Multiple Star, EN = Emission Nebula, RN = Reflection Nebula, Gal = Galaxy, GC = Globular Cluster, LY = Light Year, OC = Open cluster, PN = Planetary Nebula, SR = Supernova Remnant, CS = Carbon Star, * = Video imaging optional, ** = Video imaging recommended MAY 2008 OBJECT DESCRIPTIONS Saturn is guaranteed to be the most exciting object in the late spring and early summer sky. It is important to have some interesting stats for the public as they observe this planet. See the last page of the Object Descriptions for relevant facts. We are currently moving apart from our closest point in February. M101 is an 8th magnitude type Sc Grand Design spiral galaxy in the constellation Ursa Major (URR-suh MAY-jer). Seen in plan view, M101 is one of the most prominent spirals. Discovered by Pierre Mechain in 1781, M101 has an estimated diameter of over 170,000 light years. While nearly the apparent diameter of the moon, this galaxy is fairly faint, requiring dark skies for a quality view. M108 is an 11th magnitude type Sc spiral galaxy in the constellation Ursa Major (URR-suh-MAY-jer). Seen at an angle, the cigar-shaped object displays a disorderly collection of light and dark patches and the apparent absence of a defined galactic core. This is more apparent when viewed at higher magnification. M65 is a type Sa spiral galaxy in the constellation Leo (LEE-oh). Seen nearly edge-on, it displays a bright central core and a faint oval corona that provides a hint of spiral arms. First listed by Charles Messier in 1780, M65 forms a fairly close grouping with M66 and NGC 3628, described below. M66 is a type Sb spiral galaxy in the constellation Leo that displays a more open aspect to the viewer. The Sb designation indicates a prominent central bulge. Due to a probable close encounter with M65 in the past, M66 offers hints of a spiral arm extending away from the core, suggesting a faint tail. NGC 3628 is yet another spiral galaxy in Leo. Discovered by William Herschel in 1784, this type Sc edge-on spiral exhibits a prominent dark dust band intersecting the bright core. NGC4565 , also known as Caldwell 38, is a large type Sb spiral galaxy found in the constellation Coma Berenices (KOH-mah bera-NEE-seez), Berenices Hair. At a relatively bright 9.6 magnitude, this is a truly outstanding example of a spiral galaxy seen edge-on. The narrow disk and bright central core are bisected by a prominent dark lane of dust. This galaxy is about 150,000 light years in diameter and has a total mass of 200 billion suns. NGC4656 is a type SBm barred spiral galaxy in the constellation Canes Venatici (KAY-neez- vë-NAT-ih-si). Popularly known as the Hockey Stick Galaxy, the key features are the angled tilt of the disk and the apparent offset of the core. If observing at low magnification look in the same field of view for NGC4631, a more distant galaxy also seen edge-on. M64 is a type Sb spiral galaxy in the constellation Coma Berenices (KOH-mah bera-NEE-seez,). Popularly known as the Black Eye Galaxy, this object has a diameter of about 51,000 LY. Steady seeing will offer viewers a bright irregular shape with uneven brightness and texture. This is as a result of an unusual characteristic: the central portion of the galaxy is thought to rotate in one direction out to approximately 3,000 light years, while the outer portion of the galaxy rotates in the opposite direction! Where the two countra-rotating sections meet, the interacting dust and gas creates large areas of new star formation, seen as brighter areas. How did this happen? It is probably the odd outcome of the collision of two galaxies in the distant past. M53 is a globular cluster in the constellation Coma Berenices )KOH-mah-bera-NEE=seez). It is about 220 light years in diameter. With a combined magnitude of 7.6, it is a very compressed cluster with a slightly oval shape. While M53 orbits the Milky Way galaxy at about 60,000 light years from the galactic core, it is currently about 58,000 light years from Earth and is approaching us at 112 kilometers per second. M3 is an impressive globular cluster in the constellation Canes Venatici (KAY-neez vě-NAT-ih-si). Spanning 180 – 200 light years in diameter, this outstanding globular contains nearly 500,000 stars. Globular clusters are home to some of the oldest stars in the universe. Unlike most globulars, M3 contains a large population of variable stars. At low magnification, look for a hint of color in both the inner core and outer perimeter. M5 is a globular cluster in the constellation Serpens (SIR-penz, the serpent). Discovered by Gottfried Kirch in 1702, this 5.6 magnitude conglomeration of stars is about 13 billion years old and is approximately 165 light years in diameter. Observers may detect a distinct elliptical elongation to the main body of stars. Of interest is that red shift studies indicate that M5 is currently receding from us at about 30 miles per second in its path around the Milky Way. Iota () Cancri is a beautiful double star in the constellation Cancer (CAN-sir). Rivalling Albireo with it’s striking pair of orange and blue stars, this pair gleams at 4.1 & 6.0 magnitudes. With a separation of 31” of arc, this pair is best seen using the 4” refractor at low magnification. Observe Iota Cancri before it sets too low in the west. Cor Caroli, or Canum Venaticorum, is the brightest star in the constellation Canes Venatici (KAY-neez vě-NAT-ih-si). It is also an attractive double star for small scopes. With stellar magnitudes of 2.9 & 5.6, look for a blue-white primary and a dimmer yellow-white secondary. Try the 22mm eyepiece on the 4” refractor for the best view. Y Canum Venaticorum is a J class variable carbon star in the constellation Canes Venatici (KAY-neez vě-NAT-ih-si) that displays an unusual abundance of the carbon-13 isotope. The red color is caused by large amounts of carbon molecules such as carbon monoxide and cyanogen, in the star's outer layers. Absorption of shorter wavelengths of light by these molecules results in its intense reddish hue. SATURN FACTS Sixth planet from the Sun. Second largest planet in the solar system. Average distance from the Sun – 900 million miles Current distance from Earth – 800+ million miles Diameter is approximately 65,000 miles at the poles, and 72,000 miles at the equator. Why the difference? Average rotation period is 10 – 11 hours. Orbital period around the Sun is 29.5 years. Saturn has had observed wind speeds as high as 1100 miles per hour. Four times faster than wind speeds on Jupiter. The density of Saturn is only 0.7 grams/cubic centimeter. Less than water. The planet would float in water. An interesting fact is that Saturn radiates more heat than it receives from the Sun. Scientists speculate on why. Edge-to-edge diameter of the main ring system is over 180,000 miles Average ring thickness is only about 1 kilometer (3,000 feet). Range is from roughly 200 meters to 3000 meters. Number of major rings – 5. Thousands of minor rings Dark ring visible is the Cassini Division, a gap in the rings caused by the gravitational influence of small moons within the ring structure. 34 named moons. Largest is Titan, second largest moon in the solar system. At 3200 miles in diameter, Titan is larger than Mercury. F. Lockhart