The new image of the Rosette Nebula was taken by the Dark Energy Camera (DECam), mounted on NSF’s Víctor M. Blanco 4-m telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NOIRLab.
Cradled within the fiery petals of the Rosette Nebula is NGC 2244, the young star cluster which it nurtured. Image credit: CTIO / NOIRLab / DOE / NSF / AURA / T.A. Rector, University of Alaska Anchorage & NSF’s NOIRLab / D. de Martin & M. Zamani, NSF’s NOIRLab.
The Rosette Nebula resides approximately 5,000 light-years away from Earth in the constellation of Monoceros.
Also known as Caldwell 49, CTB 21, SH 2-275 or W 16, the object spans 1.3 degrees of sky, roughly the width of an index finger held out at arm’s length.
The Rosette Nebula has a diameter of 130 light-years — more than five times as large as the Orion Nebula.
Their apparent sizes are similar because the former is four times as distant.
“As prominent as the nebula’s ‘petals’ is the conspicuous absence of gas at its center,” the NOIRLab astronomers said in a statement.
“The culprits responsible for excavating this hollow core are the most massive stars of NGC 2244 — the open star cluster nurtured by the nebula.”
“This cluster was born around two million years ago after the nebula’s gasses coalesced into clumps brought together by their mutual gravity.”
“Eventually, some clumps grew to be massive stars that produce stellar winds powerful enough to bore a hole in the nebula’s heart.”
“NGC 2244’s massive stars also emit ultraviolet radiation, which ionizes the surrounding hydrogen gas and lights up the nebula in an array of brilliant colors,” the astronomers said.
“The billowing red clouds are regions of H-alpha emission, resulting from highly energized hydrogen atoms emitting red light.”
“Along the walls of the central cavity, closer to the massive central stars, the radiation is energetic enough to ionize a heavier atom like oxygen, which glows in shades of gold and yellow.”
“Finally, along the edges of the flower’s petals are wispy tendrils of deep pink glowing from the light emitted by ionized silicon.”
The Rosette Nebula’s bright and glowing features are certainly striking; but its dark and shadowy features also command attention.
“Around the nebula’s excavated nucleus is a string of dark clouds dubbed ‘elephant trunks,’ so-named because of their trunk-like pillars,” the researchers said.
“These structures are opaque because they contain obscuring dust, and they line the border between the hot shell of ionized hydrogen and the surrounding environment of cooler hydrogen.”
“As the shell expands outwards it encounters cold and clumpy gas that resists its push.”
“This creates the long and extended trunks whose lengths point like fingers towards the central cluster.”
“One of these dark features is the Wrench Trunk, its claw-like head seen towards the upper right of the central cluster.”
“Unlike the prototypical Pillars of Creation trunks which stand like straight columns, the Wrench’s ‘handle’ has an unusual spiral shape which traces the magnetic field of the nebula.”
“Less obvious but equally interesting are the dark globulettes.”
“Sometimes round and sometimes teardrop-shaped, these diminutive blobs of dust are smaller than the better known globules at only a few times more massive than Jupiter.”
“A string of them can be seen near the Wrench Trunk, but hundreds more dot the entire Rosette Nebula.”
“These globulettes may host brown dwarfs and planets within them.”
“In roughly 10 million years, the radiation from the hot, young stars of the NGC 2244 cluster will have dissipated the nebula.”
“By then the rosette will no longer be, and its massive stars will be left without their parent cloud.”
Source : Breaking Science News