Overview
CG 4 is a hand reaching out of the dark. Some 1,300 light years away in Puppis, this cometary globule rises from the floor of the frame like a forearm of dust, its ragged fingers curled around a hollow of crimson light. The name it has earned, God’s Hand, feels less like a nickname than a plain description.
Despite the word cometary, nothing here has anything to do with comets. CG 4 is a dense cloud of cold gas and dust adrift in the vast Gum Nebula, with a head about one and a half light years across and a faint tail that streams away for roughly eight more. The pink rim tracing its edges gives the game away. Ultraviolet light from hot, massive stars nearby is ionizing the skin of the cloud and boiling it off, layer by layer. The hand is eroding even as we admire it, though enough material remains inside to build several stars like the Sun. How these globules got their shape is still debated, with a supernova blast and the relentless winds of neighboring stars as the leading suspects. Tellingly, the tails of the Gum Nebula’s globules point away from the Vela supernova remnant at its center.
And then there is the galaxy. Poised just above the fingertips sits ESO 257-19, an edge-on spiral the hand seems about to pluck from the sky. It is a trick of perspective on a colossal scale. The galaxy lies more than a hundred million light years behind the cloud, safe by a margin that is hard to even picture.
This is a pure LRGB rendition, just over 24 hours of it, with no narrowband data at all. The red glow of the rim, the ochre and brown of the dust, the blue reflection nebulae scattered across the field, and the gray veils drifting along the bottom all come from broadband light alone. Wander the frame and dozens of tiny background galaxies shine through, a reminder of how much lies beyond a cloud that is, in cosmic terms, right next door.
Captured from my remote setup at Obstech in Chile:
🔭 PlaneWave CDK500 Observatory System
📸 Moravian C5A-100M Camera
🎨 Chroma L, R, G and B Filters
📀 L: 57×600s, R: 60×300s, G: 60×300s, B: 55×300s (24.08 hours)
🖥️ Processed in PixInsight and Adobe Photoshop