NASA’s James Webb Space Telescope has revealed the once-hidden features of the protostar within the dark cloud L1527, providing insight into the beginnings of a new star. These blazing clouds within the Taurus star-forming region are only visible in infrared light, making it an ideal target for Webb’s Near-Infrared Camera (NIRCam).
The protostar itself is hidden from view
within the “neck” of this hourglass shape. An edge-on protoplanetary disk is
seen as a dark line across the middle of the neck. Light from the protostar
leaks above and below this disk, illuminating cavities within the surrounding
gas and dust.
The protostar within the dark cloud L1527, shown in this image from NASA’s James Webb Space Telescope Near-Infrared Camera (NIRCam), is embedded within a cloud of material feeding its growth. Ejections from the star have cleared out cavities above and below it, whose boundaries glow orange and blue in this infrared view. The upper central region displays bubble-like shapes due to stellar “burps,” or sporadic ejections. Credits: NASA, ESA, CSA, and STScI. Image processing: J. DePasquale, A. Pagan, and A. Koekemoer (STScI)
Download the
full-resolution image from the Space Telescope Science Institute.
The region’s most prevalent features, the clouds colored blue and orange in
this representative-color infrared image, outline cavities created as material
shoots away from the protostar and collides with surrounding matter. The colors
themselves are due to layers of dust between Webb and the clouds. The blue
areas are where the dust is thinnest. The thicker the layer of dust, the less
blue light is able to escape, creating pockets of orange.
Webb also reveals filaments of molecular hydrogen that have been shocked as
the protostar ejects material away from it. Shocks and turbulence inhibit the
formation of new stars, which would otherwise form all throughout the cloud. As
a result, the protostar dominates the space, taking much of the material for
itself.
Despite the chaos that L1527 causes, it’s only about 100,000 years old - a
relatively young body. Given its age and its brightness in far-infrared light
as observed by missions like the Infrared Astronomical Satellite, L1527 is
considered a class 0 protostar, the earliest stage of star formation.
Protostars like these, which are still cocooned in a dark cloud of dust and
gas, have a long way to go before they become full-fledged stars. L1527 doesn’t
generate its own energy through nuclear fusion of hydrogen yet, an essential
characteristic of stars. Its shape, while mostly spherical, is also unstable,
taking the form of a small, hot, and puffy clump of gas somewhere between 20
and 40% the mass of our Sun.
As the protostar continues to gather mass, its core gradually compresses
and gets closer to stable nuclear fusion. The scene shown in this image reveals
L1527 doing just that. The surrounding molecular cloud is made up of dense dust
and gas being drawn to the center, where the protostar resides. As the material
falls in, it spirals around the center. This creates a dense disk of material,
known as an accretion disk, which feeds material to the protostar. As it gains
more mass and compresses further, the temperature of its core will rise,
eventually reaching the threshold for nuclear fusion to begin.
The disk, seen in the image as a dark band in front of the bright center,
is about the size of our solar system. Given the density, it’s not unusual for
much of this material to clump together - the beginnings of planets.
Ultimately, this view of L1527 provides a window into what our Sun and solar
system looked like in their infancy.
The James Webb Space Telescope is the world's premier space science observatory. Webb will solve mysteries in our solar system, look beyond to distant worlds around other stars, and probe the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.
Source: NASA’s Webb Catches Fiery Hourglass as New Star Forms | NASA
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