Free Astronomy Magazine November-December 2024

24 NOVEMBER-DECEMBER 2024 ASTRO PUBLISHING The Rosette Nebula’s bright and glowing features are certainly strik- ing; but its dark and shadowy fea- tures also command attention. Around the nebula’s excavated nu- cleus is a string of dark clouds dubbed ‘elephant trunks,’ so-named because of their trunk-like pillars. These struc- tures are opaque because they con- tain obscuring dust, and they line the border between the hot shell of ion- ized hydrogen and the surrounding environment of cooler hydrogen. As the shell expands outwards it encoun- ters cold and clumpy gas that resists its push. This creates the long and ex- tended trunks whose lengths point like fingers towards the central clus- ter. One of these dark features is the Wrench Trunk, its claw-like head seen towards the upper right of the cen- tral 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 in- teresting 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. Like all roses, the Rosette Nebula will not last forever, for the same stars it birthed will also bring about its death. 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. This huge 377-megapixel image is being released in celebration of NOIRLab’s fifth anniversary. On 1 Oc- tober 2019 NOIRLab’s five programs — Cerro Tololo Inter-American Ob- servatory, the Community Science and Data Center, the International Gemini Observatory, Kitt Peak Na- tional Observatory and Vera C. Rubin Observatory — were brought together under one organization. In the years since, NOIRLab’s world- class telescopes have contributed to many discoveries and countless press releases, and produced an impres- sive collection of stunning astro- nomical images showcasing our diverse and colorful Universe. T his excerpt shows some of the interesting features of the Rosette Nebula. The dashed circle highlights the nebula’s cen- tral star cluster, NGC 2244. The hazy smudge at the center of NGC 2244 is the young stellar object (YSO), Rosette HH1 (1). YSOs are stars in their early stage of evolution, before they become main-sequence stars, that often exhibit characteristics such as jets, bipolar outflows, protoplanetary discs, and other indicators of a new star being born. Around the nebula’s ex- cavated nucleus is a string of dark clouds dubbed ‘elephant trunks,’ so-named because of their trunk-like pillars (2, 4). One of these dark features is the Wrench Trunk (3). 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. This image was cap- tured with the Department of Energy-fabricated Dark Energy Camera, mounted on the U.S. National Science Foundation Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory, a Program of NSF NOIRLab. [CTIO/NOIRLab/DOE/NSF/ AURA − Image Processing: T.A. Rector (University of Alaska Anchorage/NSF NOIRLab), D. de Martin & M. Zamani (NSF NOIRLab)] !