Radiant Protostars and Shadowy Clouds Clash in Stellar Nursery

The clashing of energy and matter can lead to fantastical sites on Earth, such as glowing auroras and powerful lightning displays. The same can be said about space, where energy from bright young stars and protostars floods their surroundings, illuminating vast interstellar clouds of dust and gas to create spectacular objects known as reflection nebulae

One stunning example of these clashing forces is the star-forming interstellar cloud Lupus 3, captured here by the 570-megapixel US Department of Energy-fabricated Dark Energy Camera at NSF’s NOIRLab’s Cerro Tololo Inter-American Observatory in Chile. This star-forming nebula is located about 500 light-years from Earth in the direction of the constellation Lupus (the Wolf).

The two blue stars blazing in the center of the sprawling nebula, known as HR 5999 and HR 6000, illuminate nearby gas and dust, creating the bright blue reflection nebula Bernes 149. These stars grew out of the dark nebula Lupus 3, which stretches like a blanket across the background of stars. This cloud is not just a coal-black cosmic blob, however. It is home to a fleet of infant stars known as T Tauri stars, which will eventually use the material of Lupus 3 to grow into fully fledged stars. 

At the relatively young age of about 1 million years, HR 5999 and HR 6000 are the oldest of the stars in the Lupus 3 region. These stars are pre-main-sequence stars, meaning that despite their brightness, they are not yet powered by nuclear fusion, like our Sun. They are instead powered by gravity, which compresses and heats up the internal matter. These sibling stars have blown away nearby gas and dust, illuminating the remnants and creating the Bernes 149 reflection nebula. 

When the true nature of this nebula was first discovered, astronomers hoped that it and similar regions would be useful in finding areas of recent or active star formation. This hunch was proven correct and Lupus 3 has since provided many insights into the early stages of star formation. 

Lupus 3 is one of at least nine clouds within the massive Lupus cloud complex. Lupus 3 itself stretches across an area of the sky equivalent to about 24 Moon-diameters as seen from Earth. With a whopping 2.2-degree field of view, DECcam can capture massive objects like Lupus 3 in a single image. The pairing of DECam’s wide-field capabilities and the light-collecting capabilities of the Víctor M. Blanco 4-meter Telescope’s 4-meter-wide mirror produces crisp, high resolution images.

DECam was operated by the US Department of Energy (DOE) and NSF between 2013 and 2019 to carry out the Dark Energy Survey (DES). DECam was funded by the DOE and was built and tested at DOE’s Fermilab. Now DECam is used for programs covering a huge range of science research.

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NSF’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory), the US center for ground-based optical-infrared astronomy, operates the international Gemini Observatory (a facility of NSFNRC–CanadaANID–ChileMCTIC–BrazilMINCyT–Argentina, and KASI–Republic of Korea), Kitt Peak National Observatory (KPNO), Cerro Tololo Inter-American Observatory (CTIO), the Community Science and Data Center (CSDC), and Vera C. Rubin Observatory (operated in cooperation with the Department of Energy’s SLAC National Accelerator Laboratory). It is managed by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with NSF and is headquartered in Tucson, Arizona. The astronomical community is honored to have the opportunity to conduct astronomical research on Iolkam Du’ag (Kitt Peak) in Arizona, on Maunakea in Hawai‘i, and on Cerro Tololo and Cerro Pachón in Chile. We recognize and acknowledge the very significant cultural role and reverence that these sites have to the Tohono O’odham Nation, to the Native Hawaiian community, and to the local communities in Chile, respectively.