The Tarantula Nebula, a turbulent star-birth region located in the Large Magellanic Cloud, hosts thousands of young and still-forming stars, many revealed by the NASA/ESA/CSA James Webb Space Telescope for the first time.
This 340-light-year-wide image from Webb’s Near-Infrared Camera (NIRCam) shows the Tarantula Nebula. The most active region appears to sparkle with massive young stars, appearing pale blue. Scattered among them are still-embedded stars, appearing red, yet to emerge from the dusty cocoon of the nebula. NIRCam is able to detect these dust-enshrouded stars thanks to its unprecedented resolution at near-infrared wavelengths. To the upper left of the cluster of young stars, and the top of the nebula’s cavity, an older star prominently displays NIRCam’s distinctive eight diffraction spikes, an artifact of the telescope’s structure. Following the top central spike of this star upward, it almost points to a distinctive bubble in the cloud. Young stars still surrounded by dusty material are blowing this bubble, beginning to carve out their own cavity. Farther from the core region of hot young stars, cooler gas takes on a rust color, telling astronomers that the nebula is rich with complex hydrocarbons. This dense gas is the material that will form future stars. As winds from the massive stars sweep away gas and dust, some of it will pile up and, with gravity’s help, form new stars. Image credit: NASA / ESA / CSA / STScI / Webb ERO Production Team.
The Tarantula Nebula lies about 163,000 light-years away in the southern constellation of Dorado.
Also known as NGC 2070 or 30 Doradus, the nebula is part of the Large Magellanic Cloud, one of our closest galactic neighbors.
The bright glow of the Tarantula Nebula was first recorded by French astronomer Nicolas-Louis de Lacaille in 1751.
At its heart are some of the most massive stars known, a few with more than 150 times the mass of our Sun.
Star formation in the Tarantula Nebula started tens of millions of years ago, though it was not confined to a specific region.
Instead, as enough gas accumulated, pockets of star birth burst to life erratically, like the finale of a fireworks show.
“One of the reasons the Tarantula Nebula is interesting to astronomers is that the nebula has a similar type of chemical composition as the gigantic star-forming regions observed at the Universe’s ‘cosmic noon,’ when the cosmos was only a few billion years old and star formation was at its peak,” Webb astronomers said.
“Star-forming regions in our Milky Way Galaxy are not producing stars at the same furious rate as the Tarantula Nebula, and have a different chemical composition.”
“This makes the Tarantula the closest — i.e., easiest to see in detail — example of what was happening in the Universe as it reached its brilliant high noon.”
The astronomers focused three of Webb’s high-resolution infrared instruments on the Tarantula Nebula.
“Viewed with Webb’s Near-Infrared Camera (NIRCam), the region resembles a burrowing tarantula’s home, lined with its silk,” they said.
“The nebula’s cavity centered in the NIRCam image has been hollowed out by blistering radiation from a cluster of massive young stars, which sparkle pale blue in the image.”
“Only the densest surrounding areas of the nebula resist erosion by these stars’ powerful stellar winds, forming pillars that appear to point back toward the cluster.”
“These pillars contain forming protostars, which will eventually emerge from their dusty cocoons and take their turn shaping the nebula.”
At the longer wavelengths of light captured by its Mid-Infrared Instrument (MIRI), Webb focuses on the area surrounding the central star cluster and unveils a very different view of the Tarantula Nebula. In this light, the young hot stars of the cluster fade in brilliance, and glowing gas and dust come forward. Abundant hydrocarbons light up the surfaces of the dust clouds, shown in blue and purple. Much of the nebula takes on a more ghostly, diffuse appearance because mid-infrared light is able to show more of what is happening deeper inside the clouds. Still-embedded protostars pop into view within their dusty cocoons, including a bright group at the very top edge of the image, left of center. Other areas appear dark, like in the lower-right corner of the image. This indicates the densest areas of dust in the nebula, that even mid-infrared wavelengths cannot penetrate. These could be the sites of future, or current, star formation. Image credit: NASA / ESA / CSA / STScI / Webb ERO Production Team.
Webb’s Near-Infrared Spectrograph (NIRSpec) caught one very young star doing just that.
“We previously thought this star might be a bit older and already in the process of clearing out a bubble around itself,” the researchers said.
“However, NIRSpec showed that the star was only just beginning to emerge from its pillar and still maintained an insulating cloud of dust around itself.”
“Without Webb’s high-resolution spectra at infrared wavelengths, this episode of star formation-in-action could not have been revealed.”
Webb’s Near-Infrared Spectrograph (NIRSpec) reveals what is really going on in an intriguing region of the Tarantula Nebula. The signature of atomic hydrogen, shown in blue, shows up in the star itself but not immediately surrounding it. Instead, it appears outside the ‘bubble,’ which spectra show is actually filled with molecular hydrogen (green) and complex hydrocarbons (red). This indicates that the bubble is actually the top of a dense pillar of dust and gas that is being blasted by radiation from the cluster of massive young stars to its lower right. It does not appear as pillar-like as some other structures in the nebula because there is not much color contrast with the area surrounding it. The harsh stellar wind from the massive young stars in the nebula is breaking apart molecules outside the pillar, but inside they are preserved, forming a cushy cocoon for the star. This star is still too young to be clearing out its surroundings by blowing bubbles — NIRSpec has captured it just beginning to emerge from the protective cloud from which it was formed. Without Webb’s resolution at infrared wavelengths, the discovery of this star birth in action would not have been possible. Image credit: NASA / ESA / CSA / STScI / Webb ERO Production Team.
The Tarantula Nebula takes on a different appearance when viewed in the longer infrared wavelengths detected by Webb’s Mid-infrared Instrument (MIRI).
“The hot stars fade, and the cooler gas and dust glow,” the scientists said.
“Within the stellar nursery clouds, points of light indicate embedded protostars, still gaining mass.”
“While shorter wavelengths of light are absorbed or scattered by dust grains in the nebula, and therefore never reach Webb to be detected, longer mid-infrared wavelengths penetrate that dust, ultimately revealing a previously unseen cosmic environment.”
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This article is based on text provided by the National Aeronautics and Space Administration.
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