The Gum Nebula is an emission nebula nearly 1400 light-years away. It’s house to an object often called “God’s Hand” among the many devoted. The remainder of us name it CG 4.
Many objects in house tackle fascinating, ethereal shapes straight out of somebody’s psychedelic fantasy. CG4 is certainly ethereal and extraordinary, however it’s additionally a bit of extra prosaic. It appears like a hand extending into house.
The Darkish Vitality Digicam (DECam) on the NSF’s Víctor M. Blanco 4-meter Telescope captured the picture. DECam’s main job is to survey lots of of hundreds of thousands of galaxies in its examine of darkish power. But it surely’s additionally a general-purpose instrument used for different scientific endeavours.
CG 4 is named a cometary globule due to its look. But it surely’s truly a star-forming area. It has a head that’s about 1.5 light-years in diameter and a tail that’s about 8 light-years lengthy. The top is dense and opaque and is lit up by a close-by star. The globule is surrounded by a diffuse crimson glow, emissions from ionized hydrogen.
Picture Processing: T.A. Rector (College of Alaska Anchorage/NSF’s NOIRLab), D. de Martin & M. Zamani (NSF’s NOIRLab)
There are many cometary globules within the Milky Approach. They’re a sub-class of objects known as Bok globules, after astronomer Bart Bok, who found them. Each sorts of globules are dark nebulae, molecular clouds so dense they block optical mild. Astronomers aren’t completely sure how cometary globules get their form.
However they do know what’s taking place to them.
The crimson glow surrounding CG 4 is ionized hydrogen lit up by radiation from close by sizzling, huge stars. That very same radiation is eroding CG 4 away. For the reason that globule is denser than its environment, it’s resisting diffusion. It nonetheless accommodates sufficient fuel and dirt to kind a number of new stars about as huge because the Solar.
Though there are various of those globules within the Milky Approach, the vast majority of them are within the Gum Nebula. Scientists know of 31 different globules within the nebula. This one’s known as CG 4 (Cometary Globule 4) as a result of they’re all numbered.
The Gum Nebula is probably going the remnant of an enormous supernova explosion, and that may very well be the explanation the globules have their distinctive form. They could have initially been spherical nebula just like the Ring Nebula. However a robust supernova explosion about a million years in the past stretched them into their lengthy, comet-like kinds.
Astronomers additionally recommend one more reason for his or her form. Close by sizzling, huge stars exert radiation stress on the globules, and their stellar wind additionally slams into them. Within the Gum Nebula, their tails level away from the Vela Supernova Remnant and the pulsar that sits in its centre. For the reason that Vela Pulsar is a spinning neutron star, it’s attainable that its winds and radiation stress are shaping CG 4.
No matter its trigger, the Hand of God is a visually intriguing object. In case you actually wish to lose your self on this superb nebula, obtain the TIFF file here.
