New Photo Reveals Cosmic Unicorn's Heart

An extraordinary starscape of glowing gas, dark clouds and young stars within the Unicorn constellation ??has been captured by astronomers using the telescopes at the European Southern Observatory.

The infrared view shows an active stellar nursery hidden within a huge, dark cloud at the heart of the Unicorn constellation, also known as Monoceros. This star-forming region, known as Monoceros R2, is embedded within a massive dark cloud that is rich in molecules and dust. [New photo of Unicorn constellation.]

When observed from Earth, the Unicorn constellation appears close to the more familiar Orion nebula, but the location of the constellation is actually almost twice as far away, at a distance of about 2,700 light-years.

In visible light, a grouping of massive hot stars creates a beautiful collection of reflection nebulas ? so called because the clouds of gas and dust reflect light from nearby bright stars. In this new image, the blue starlight is scattered from parts of the dark, foggy outer layers of the molecular cloud.

Most of the massive newborn stars, however, remain hidden behind the thick interstellar dust that strongly absorbs their ultraviolet and visible light. In fact, the star-forming Monoceros R2 region is almost completely obscured by interstellar dust when viewed in visible light.

The Monoceros R2 cluster has a dense core which is packed with very massive young stars. Other bright infrared sources are also visible, which are typically newborn massive stars still surrounded by dusty disks.

The spectacular new infrared image was taken by ESO's Visible and Infrared Survey Telescope for Astronomy (VISTA) at the Paranal Observatory in northern Chile. The region lies at the center of the image, where a much higher concentration of stars is visible on close inspection, and where the prominent reddish features probably indicate molecular hydrogen emissions.

The infrared telescope is capable of penetrating the region's dark curtain of cosmic dust to reveal the folds, loops and filaments that have been sculpted from the interstellar matter. These glowing tendrils of gas were shaped by intense particle winds and the radiation emitted by hot, young stars.

"When I first saw this image I just said 'Wow!'" said Jim Emerson, a professor of Astrophysics at Queen Mary, University of London, and leader of the 18-university VISTA consortium in the United Kingdom.

"I was amazed to see all the dust streamers so clearly around the Monoceros R2 cluster, as well as the jets from highly embedded young stellar objects," Emerson said. "There is such a great wealth of exciting detail revealed in these VISTA images."

The most massive of these stars are less than 10 million years old.

Stars form in a process that typically lasts a few million years and which takes place inside large clouds of interstellar gas and dust hundreds of light-years across. Because the interstellar dust is opaque to visible light, infrared and radio observations are crucial in the understanding of the earliest stages of the stellar evolution.

The ESO image was created from exposures taken in three different parts of the near-infrared spectrum.

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