Stellar Nursery in Carina – Astronomy Now

What looks a lot like craggy mountains on a moonlit evening is actually the edge of a young star-forming region near NGC 3324 in the Carina Nebula. Captured in infrared light by the Near Infrared Camera (NIRCam) of NASA’s James Webb Space Telescope, this image reveals previously obscured star birth zones. Image: NASA, ESA, CSA, STScI.

The seemingly three-dimensional “cosmic cliffs” showcase Webb’s abilities to peer through obscuring dust and shed new light on star formation. Webb reveals emerging stellar nurseries and individual stars that are completely hidden in visible light images. This landscape of “mountains” and “valleys” is actually the edge of a nearby stellar nursery called NGC 3324 at the northwest corner of the Carina Nebula.

The so-called mountains – some towering about seven light-years high – are dotted with twinkling young stars imaged in infrared light. A cavernous area has been carved into the nebula by intense ultraviolet radiation and stellar winds from extremely massive and hot young stars above the area shown in this image. The blistering ultraviolet radiation from these stars carves the wall of the nebula, slowly eroding it. Dramatic pillars rise above the wall of glowing gas, resisting this radiation. The “steam” that appears to rise from the celestial “mountains” is actually hot, ionized gas and hot dust escaping from the nebula due to the incessant radiation.

Astronomers using NASA’s James Webb Space Telescope have combined the capabilities of the telescope’s two cameras to create a never-before-seen view of a star-forming region in the Carina Nebula. Captured in infrared light by the Near Infrared Camera (NIRCam) and Mid Infrared Instrument (MIRI), this combined image reveals previously invisible star birth zones. Image: NASA, ESA, CSA, STScI

Objects in the early, rapid phases of star formation are difficult to capture, but Webb’s extreme sensitivity, spatial resolution, and imaging ability can chronicle these elusive events.

This landscape of “mountains” and “valleys” dotted with twinkling stars is actually the edge of a nearby young star-forming region called NGC 3324 in the Carina Nebula. Captured in infrared light by NASA’s new James Webb Space Telescope, this image reveals previously invisible star birth zones for the first time.

Called Cosmic Cliffs, Webb’s seemingly three-dimensional image resembles craggy mountains on a full moon night. It’s actually the edge of the giant gas cavity in NGC 3324, and the tallest “peaks” in this image are about 7 light-years high. The cavernous area was carved into the nebula by intense ultraviolet radiation and stellar winds from extremely massive and hot young stars located in the center of the bubble, above the area shown in this image.

The blistering ultraviolet radiation from young stars sculpts the wall of the nebula, slowly eroding it. Dramatic pillars dominate the wall of glowing gas, resistant to this radiation. The “steam” that appears to rise from the celestial “mountains” is actually hot, ionized gas and hot dust escaping from the nebula due to the incessant radiation.

Webb reveals emerging stellar nurseries and individual stars that are completely hidden in visible light images. Due to Webb’s sensitivity to infrared light, he can peer through cosmic dust to see these objects. Protostellar jets, which stand out clearly in this image, shoot out from some of these young stars. The younger sources appear as red dots in the dark, dusty region of the cloud. Objects in the early, rapid phases of star formation are difficult to capture, but Webb’s extreme sensitivity, spatial resolution, and imaging ability can chronicle these elusive events.

These observations of NGC 3324 will shed light on the process of star formation. Star birth propagates through time, triggered by the expansion of the erosion cavity. As the bright, ionized edge moves through the nebula, it slowly pushes through gas and dust. If the rim encounters unstable material, the increased pressure will trigger the material to collapse and new stars to form.

Conversely, this type of disturbance can also prevent star formation because the star-making material is eroded. It’s a very delicate balance between triggering star formation and stopping it. Webb will address some of the big open questions in modern astrophysics: what determines how many stars form in a certain region? Why do stars form with a certain mass?

Webb will also reveal the impact of star formation on the evolution of gigantic clouds of gas and dust. While the effect of massive stars – with their strong winds and high energy – is often apparent, less is known about the influence of more numerous low-mass stars. As they form, these smaller stars create the narrow, opposing jets seen here, which can inject a lot of momentum and energy into the clouds. This reduces the fraction of nebular matter that spawns new stars.

Until now, scientists had very little data on the influence of the multitude of young, more energetic low-mass stars. Together with Webb, they will be able to get a full census of their numbers and impact throughout the Nebula.

Located about 7,600 light-years away, NGC 3324 was imaged by Webb’s Near Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI).

NIRCam – with its crisp resolution and unparalleled sensitivity – uncovers hundreds of previously hidden stars, and even many background galaxies.

According to MIRI, young stars and their dusty planet-forming disks glow brightly in the mid-infrared, appearing pink and red. MIRI reveals structures that are embedded in dust and uncovers stellar sources of massive jets and outflows. With MIRI, hot dust, hydrocarbons and other chemical compounds on the surface of the ridges glow, giving the appearance of jagged rocks.

NGC 3324 was first cataloged by James Dunlop in 1826. Visible from the southern hemisphere, it is located at the northwest corner of the Carina Nebula (NGC 3372), which resides in the constellation Carina. The Carina Nebula is home to the Keyhole Nebula and the active and unstable supergiant star called Eta Carinae.

Dora W. Clawson