Herschel Spots a Hot Young Star-Forming Butterfly

July 15, 2012 — This explosion of red, orange and blue may look like an abstract work of art but it’s actually a vast region of interstellar gas and dust where stars are being born, 2,300 light-years away from Earth.

Vela-C is a molecular cloud, part of the larger Vela Molecular Ridge structure within our Milky Way galaxy. Seen here in an image by ESA’s Herschel Space Observatory, Vela-C’s intricate, wispy filaments glow in far-infrared wavelengths. Shown in bright red, the coldest, densest parts of the cloud are where gas will gradually collapse under the force of its own gravity and eventually form stars. In fact, some stars have already formed in Vela-C — they are hiding inside the blue “butterfly” (called RCW 36) which shines in shorter wavelengths of light generated by the heat of the young, massive stars within.

These stars, each more massive than the sun, will burn through their stellar fuel relatively quickly, exploding in supernovae only 10 million years after their formation. (By comparison our sun is expected to have a life span of about 9-10billion years, which it is currently in the middle of.)

The blue ring-shaped object at lower right is thought to be a similar structure to RCW 36, except that it may or may not be part of the Vela-C cloud.

Because different types of stars at different stages of formation are observed in Vela-C (and it’s relatively close by) it’s a great “natural laboratory” for astronomers studying the life cycles of stars, and Herschel’s long-wavelength capabilities make it the perfect instrument with which to observe the structure of starbirth.

via ESA:

A beautiful blue butterfly flutters towards a nest of warm dust and gas, above an intricate network of cool filaments in this image of the Vela C region by ESA’s Herschel space observatory.
Vela C is the most massive of the four parts of the Vela complex, a massive star nursery just 2300 light-years from the Sun. It is an ideal natural laboratory for us to study the birth of stars.

Herschel’s far-infrared detectors can spot regions where young high- and low-mass stars have heated dense clumps of gas and dust, where new generations of stars may be born.

The eye is immediately drawn to two prominent features in this image: a delicate blue and yellow butterfly shape just right of centre that appears to be flying towards a nest of coiled blue material in the lower right.

These regions stand out from their surroundings because their dust has been heated by young hot stars. A cluster of very hot, massive stars are strung out along the butterfly’s ‘body’, their radiation heating up the surrounding dust seen as yellow in this scene.

These heavy stars will follow ‘live fast, die young’, burning brightly for only a short time in cosmic terms. Those with more than eight times the mass of our own Sun will explode as cataclysmic supernovas within 10 million years of forming.

A particularly dense trunk of cool gas and dust weaves its way through the centre of the image, surrounded by a complex network of wispy red filaments.

Deeply embedded inside the filaments are numerous point-like sources, particularly evident towards the left of the scene: these are protostars, the seeds of new stars that will soon also light up the Vela region of the sky.  

The Vela C region, part of the Vela complex, by ESA’s Herschel space observatory. The image demonstrates Herschel’s ability to trace both high- and low-mass star formation at a range of evolutionary stages, from cool filaments, pre-stellar cores and protostars to more evolved regions containing dust that has been gently heated by hot stars.

The image was mapped using Herschel instruments PACS and SPIRE at wavelengths of 70, 160, and 250 microns, corresponding to the blue, green and red channels, respectively. North is to the right and east is up.

Credits: ESA/PACS & SPIRE Consortia, T. Hill, F. Motte, Laboratoire AIM Paris-Saclay, CEA/IRFU – CNRS/INSU – Uni. Paris Diderot, HOBYS Key Programme Consortium

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Image 2: 

In this richly detailed infrared image taken by the European Space Agency’s Herschel Space Observatory, finger-like pillars of dust can be seen hanging off growing stars. Herschel’s instrumentation has cut through the cool dust that usually obscures this region, highlighting the hot dust inside the stellar nursery.

To the right of the image, there’s a cavity caused by strong stellar winds and intense radiation emanating from the nebula’s massive star cluster (out of shot, to the right of the image) blowing back the dust, compressing it and creating long nebulous fingers. In the tips of these fingers there are a young generation of embryonic stars, sparked to life by the clumping of compressed material.

The Rosette Nebula is located approximately 5,000 light years from Earth in the constellation Monoceros (the Unicorn) and Herschel is sensitive to the glow from the nebulous clouds heated by stars of different ages. But it is the baby stars hiding inside the fingers of dusty cocoons — growing to masses in excess of 10 suns — that Herschel has spotted for the first time.

Studying star-forming regions inside Milky Way nebulae is important to help astronomers study the light received from other galaxies. As we can resolve the stars and their stellar nurseries up-close in our own galaxy, comparisons can be made, helping us understand how other galaxies form.

—Ian O’Neill, Discovery News

Image credit: ESA and the PACS, SPIRE & HSC consortia