NGC 1569: Starburst in a Dwarf Irregular Galaxy
Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact, as pictured here, dwarf galaxy NGC 1569 is apparently undergoing a burst of star forming activity, thought to have begun over 25 million years ago.
Acknowledgement: A. Aloisi (STScI/ESA) et al.
Hidden Galaxy IC 342
Image Credit & Copyright: Ed Henry (Hay Creek Observatory)
NASA- Hubble Serves Up a Holiday Space Angel
NASA’s Hubble Space Telescope presents a festive holiday greeting that’s out of this world. The bipolar star-forming region, called Sharpless 2-106, looks like a soaring, celestial snow angel. The outstretched “wings” of the nebula record the contrasting imprint of heat and motion against the backdrop of a colder medium.
NGC 6302: Bug Nebula
Distance: 3,500 Light Years Away From The Sun
NGC 6302 is a high excitation multi-polar planetary nebula first studied by Emerson Barnard in 1907. The complex planetary nebula is approximately 1900 years old and is expanding at 600 KM/sec.
Summary & Copyright: Robert Gendler
Sungrazer Lovejoy: Significant Comet Plunges Towards The Sun
A comet nearly as wide as two football fields (200m) is plunging toward the sun where it will most likely be destroyed in a spectacular light show on Dec. 15/16.
Although Comet Lovejoy (C/2011 W3) could become as bright as Jupiter or Venus when it “flames out,” the glare of the sun will hide the event from human eyes. Solar observatories in space, however, will have a grand view. Yesterday the brightening comet entered the field of view of NASA’s STEREO-B spacecraft.
“You can clearly see the comet heading diagonally through the images,” says Karl Battams of the Naval Research Lab who prepared the animation. “During the 16-hour sequence, the comet brightens from magnitude +8 to +6.5, approximately.”
It will soon grow much brighter. “This comet is a true sungrazer, and will skim approximately 140,000 km (1.2 solar radii) above the solar surface on Dec. 15/16,” notes Battams. At such close range, solar heating will almost certainly destroy the icy interloper,creating a cloud of vapor and comet dust that will reflect lots of sunlight. The Solar and Heliospheric Observatory (SOHO) will have a particularly good view.
Thor’s Helmet: NGC 2359 in Canis Major
Distance 15,000 light years
In astrophotographs NGC 2359 has an ethereal quality. Surprisingly the outward appearance strongly contradicts the violent events which gave rise to the peculiar nebula. NGC 2359 is a prototypical wind blown bubble powered by the extremely massive and unstable Wolf-Rayet star HD 56925.
These types of stars (only about 300 are known presently) represent a late evolutionary phase of massive O-type blue giants which have become unstable in the late stages of their short stellar life. WR stars heavily influence the surrounding interstellar medium.
There are several basic types of nebulae associated with WR stars which run the gamut from concentric rings (NGC 6888), wind blown bubbles (NGC 7635), to filamentary type nebulae (NGC 2359). NGC 2359 consists of two distinct components.
—Credit Copyright: Robert Gendler