While drifting through the cosmos, a magnificent interstellar dust cloud became sculpted by stellar winds and radiation to assume a recognizable shape. Fittingly named the Horsehead Nebula, it is embedded in the vast and complex Orion Nebula (M42). A potentially rewarding but difficult object to view personally with a small telescope, the above gorgeously detailed image was recently taken ininfrared light by the orbiting Hubble Space Telescope in honor of the 23rd anniversary of Hubble’s launch. The dark molecular cloud, roughly 1,500 light years distant, is cataloged as Barnard 33 and is seen above primarily because it is backlit by the nearby massive star Sigma Orionis. The Horsehead Nebula will slowly shift its apparent shape over the next few million years and will eventually be destroyed by the high energy starlight.
What looks like a puff-ball is surely the remains of the brightest supernova in recorded human history. In 1006 AD, it was recorded as lighting up the nighttime skies above areas now known asChina, Egypt, Iraq, Italy, Japan, and Switzerland. The expanding debris cloud from the stellar explosion, found in the southerly constellation the Wolf (Lupus), still puts on a cosmic light show across theelectromagnetic spectrum. In fact, the above image results from three colors of X-rays taken by the orbiting Chandra X-ray Observatory. Now known as the SN 1006 supernova remnant, the debris cloud appears to be about 60 light-years across and is understood to represent the remains of a white dwarf star. Part of a binary star system, the compact white dwarf gradually captured material from its companion star. The buildup in mass finally triggered a thermonuclear explosion that destroyed the dwarf star. Because the distance to the supernova remnant is about 7,000 light-years, that explosion actually happened 7,000 years before the light reached Earth in 1006. Shockwaves in the remnant accelerate particles to extreme energies and are thought to be a source of the mysterious cosmic rays.
This skyscape finds an esthetic balance of interstellar dust and gas residing in the suburbs of the nebula rich constellation of Orion. Reflecting the light of bright star Rigel, Beta Orionis, the jutting, bluish chin of the Witch Head Nebula is at the upper left. Whiskers tracing the red glow of hydrogen gas ionized by ultraviolet starlight seem to connect that infamous visage with smaller nebulae, like dusty reflection nebula NGC 1788 at the right. Strong winds from Orion’s bright stars have also shaped NGC 1788, and likely triggered the formation of the young stars within. Appropriate for its location, NGC 1788 looks to some like a cosmic bat. The scene spans about 3 degrees on the sky or 6 full Moons.
Every time circling the Earth (about 90 minutes), the astronauts watch sunrises and sunsets 16 times a day. Let’s just look at things familiar to us from unusual places.
A tapestry of footage tracing the cosmic and biological origins of our species, set to original music.
On planet Gliese 876d, sunrises might be dangerous. Although nobody really knows what conditions are like on this close-in planet orbiting variable red dwarf star Gliese 876, the above artistic illustration gives one impression.