Astronomy Picture Of the Day (APOD)Z is for Mars
This composite of images spaced about a week apart - from late July 2005 (bottom right) through February 2006 (top left) - traces the retrograde motion of ruddy-colored Mars through planet Earth's night sky. On November 7th, 2005 the Red Planet was opposite the Sun in Earth's sky (at opposition).
NGC 253: Dusty Island Universe
Shiny NGC 253, sometimes called the Silver Dollar Galaxy, is one of the brightest spiral galaxies visible - and also one of the dustiest. First swept up in 1783 by mathematician and astronomer Caroline Herschel, the dusty island universe lies a mere 10 million light-years away in the southern constellation Sculptor.
A Dust Cloud in NGC 281
Stars themselves can create huge and intricate dust sculptures from the dense and dark molecular clouds from which they are born. The tools the stars use to carve their detailed works are high energy light and fast stellar winds.
Mars and the Star Clusters
This evening's skyscape includes a view similar to this one, recorded in western skies on April 16 - an orange-hued planet Mars wandering near rich open star cluster M35. Also notable is fainter star cluster NGC 2158, just above and left of M35.
NGC 246 and the Dying Star
Appropriately nicknamed "the Skull Nebula", planetary nebula NGC 246 really does surround a dying star some 1,600 light-years away in the constellation Cetus. Expelled over a period of thousands of years, the lovely, intricate nebula is the outer atmosphere of a once sun-like star.
Barnards Loop around the Horsehead Nebula
Why is the Horsehead Nebula surrounded by a bubble? Although glowing like an emission nebula, the origin of the bubble, known as Barnard's Loop, is currently unknown. Progenitor hypotheses include the winds from bright Orion stars and the supernovas of stars long gone.
A Solar Prominence from SOHO
How can gas float above the Sun? Twisted magnetic fields arching from the solar surface can trap ionized gas, suspending it in huge looping structures. These majestic plasma arches are seen as prominences above the solar limb.
Galaxy Wars: M81 versus M82
In this stunning cosmic vista, galaxy M81 is on the left surrounded by blue spiral arms. On the right marked by massive gas and dust clouds, is M82. These two mammoth galaxies have been locked in gravitational combat for the past billion years.
Smoke from the Cigar Galaxy
Very bright in infrared light, well-known starburst galaxy M82's popular name describes its suggestive shape seen at visible wavelengths - The Cigar Galaxy. Ironically, M82's fantastic appearance in this Spitzer Space Telescope image...
Star Cluster Dreams
Located some 7,000 light-years away toward the constellation Perseus, this pair of open or galactic star clusters really is visible to the unaided eye and was cataloged in 130 BC by Greek astronomer Hipparchus.