If you haven’t seen this picture yet, I’m glad you are now. Amazing, isn’t it? What you’re staring at are blue “bullets” of iron-rich gas shot out from growing stars inside the Orion Nebula. The bullets measure some 70 billion miles across (10x the size of Pluto’s orbit) and create tubular wakes in the nebula’s dust and gas as they plow through hydrogen gas, setting it aglow. Some of traceries are 1/5 of a light year long.
Most stars not only radiate heat but also lose material from their hot surfaces in winds. We’re familiar with the sun’s solar wind, a tenuous stream of protons and electrons that flows away from our star at a speed of around 300 miles per second. The sun loses 1/100,000,000,000,000th (that’s one-trillionth) of its mass per year because of its windy ways.
Massive stars are extremely hot and brilliant. The power of their energetic light accelerates material off the star with gale force winds. While the sun will only lose about .01 percent of its material during its expected 10 billion year lifetime, giant stars, like those powering the bullets, slough off 1/100,000th of a sun’s worth of mass every year. During its brief life, a massive star can lose up to half the material with which it started.
Astronomers used the 8.1-meter (319-inch) Gemini South telescope in Chile to snap the first pictures of the bullets in 2007 and then again on December 28, 2012 with an adaptive optics setup that greatly reduced atmospheric turbulence. The result: super-sharp images. If you study this animation of before and after photos, you’ll see subtle but real changes in the structure and position of the pillars and knots. The universe sits still for no one – everything’s on the move! While we know that intuitively, seeing it is quite another thing. Read more about the photos and science behind the story HERE.
While you and I can’t see the bullets through our toddling telescopes, we can see where all the action’s happening – the Orion Nebula. The nebula is faintly visible with the naked eye as a fuzzy spot in Orion’s Sword, a vertical stack of three fainter stars below Orion’s famous belt.
Consisting of a 24-light-year-wide spread of dust and gas arrayed in glowing pink and green tendrils, the Orion Nebula is nothing short of a huge factory cranking out stars like loaves of bread at a bakery.
Denser knots of material with the nebula succumb to the force of gravity and collapse into brand new suns. Many are small and lost in the nebula’s misty folds, but some are supergiants with windy temperaments.
Little more than a wisp to the naked eye, the Orion Nebula easily shows a cocoon-like shape in binoculars from suburban and rural skies.
The real fun comes in the telescope. I’d guess I’ve looked at this cosmic wonder at least 500 times during my life. There’s simply no good reason not to dial it up for a view during fall, winter and even early spring. When it comes to winter deep sky objects, the Orion Nebula’s makes for tasty, low-hanging fruit.
Not only is it loaded with gaseous detail in the shape of arms, wings, petals and pleats, but at its center shines the exquisite Trapezium, a compact star cluster arranged in a trapezoid. The brightest, largest and most luminous of the quartet is Theta-1 Orionis. Its massive outpouring of ultraviolet light makes it the nebula’s primary illuminator. Take away Theta-1 and there wouldn’t be much left to see. Theta also blasts strong winds into the surrounding nebulosity, stripping away material from stars in the birthing process. These nasty habits guarantee a short life; Theta-1 burns its fuel so rapidly it will likely explode as a supernova in just a few million years.
While it may look like a quiet, fuzzy place on a still winter night, the Orion Nebula is teeming with activity. Have a look sometime and it won’t be hard to imagine those crazy cosmic bullets whizzing about.