Our feature constellation for April is Canes Venatici. Canes Venatici (the hunting dogs) was named by Polish astronomer Johannes Hevelius, The northern of the two hunting dogs is Asterion; the southern dog is Chara. Both are companions of the bear herder, Bootes, in his pursuit of the bear, Ursa Major. They chase the bear endlessly around the North celestial pole.
La Superba (HIP 62223) - A deep red variable carbon star. One of the reddest stars in the night sky, and fairly bright with magnitude varying from 4.8 to 6.3 over a 158 day cycle. The surface temperature is a mere 2800 degrees.
Globular Cluster M3 - One of the finest globular clusters in the night sky. The mag. 7 cluster is 35,000 light years distant and consists of nearly a half million stars. It's one of the brightest clusters with a luminosity of over a quarter million suns. The cluster spans a diameter of around 180 light years.
NGC 4244, The Silver Needle Galaxy - A large, edge-on galaxy estimated to be 4-8 million light years away. The galaxy spans over 15 arc-minutes - half the width of the full moon! This is also item 26 on the Caldwell list.
NGC 4214 - An irregular dwarf/Wolf Rayet starburst galaxy. The galaxy is about 13 million light-years away, and shows numerous star forming regions. Pictured at right is a Sloan Digital Sky Survey image of the irregular galaxy.
NGC 4631, The Whale Galaxy (Arp 281, Caldwell 32) - The large, nearly edge-on galaxy in the upper right of the SDSS image on the left is rated one of the finest irregular (Arp) galaxies for visual observation. NGC 4631 is about 25 million light-years distant with an apparent magnitude of 9.7.
NGC 4656, 4657, The Hockey Stick - The large galaxy to the lower left in the SDSS image on the left has been distorted by the interaction with NGC 4631. The two are separated by only around 1.7 million light-years. Through the telescope, the angular separation is only 32 arc-minutes, allowing 4656 and 4631 to often be seen in the same field of view. The stick's 'blade' was assigned a separate designation, NGC 4657.
M63 (The Sunflower Galaxy) - A large bright (mag. 8.6) spiral (Sb) galaxy about 37 million light years distant. The stars near the edge of the galaxy move so quickly that they should fly away from the galaxy. Yet something unseen holds them. More evidence for Dark Matter.
Interacting Galaxies M51 (The Whirlpool Galaxy) and NGC 5195 - The image on the right showing the interacting galaxies M51 and NGC 5195 was taken by ASLC member, George Hatfield. Both are about 31 million light-years distant. M51 is a classic Sb galaxy with numerous H2 (star forming) regions. A recent Hubble Telescope image shows these H2 regions in great detail (click here to see the image). At magnitude 8.9, M51 is an easy target for modest telescopes.
March's DSO Tour of Coma Berenices is still on-line in case you didn't get a chance to do it. Click here.
