Showing posts with label protostars. Show all posts
Showing posts with label protostars. Show all posts

Sunday, July 13, 2025

NASA's Webb Scratches Beyond Surface of Cat's Paw for 3rd Anniversary

Cat's Paw Nebula (NIRCam Image)
Credits/Image: NASA, ESA, CSA, STScI

Cat's Paw (NIRCam) Compass Image
Credits/Image: NASA, ESA, CSA, STScI



It’s the cat’s meow! To celebrate its third year of revealing stunning scenes of the cosmos in infrared light, NASA’s James Webb Space Telescope has “clawed” back the thick, dusty layers of a section within the Cat’s Paw Nebula (NGC 6334). Focusing Webb’s NIRCam (Near-Infrared Camera) on a single “toe bean” within this active star-forming region revealed a subset of mini toe beans, which appear to contain young stars shaping the surrounding gas and dust.

Webb’s look at this particular area of the Cat’s Paw Nebula just scratches the surface of the telescope’s three years of groundbreaking science.

“Three years into its mission, Webb continues to deliver on its design – revealing previously hidden aspects of the universe, from the star formation process to some of the earliest galaxies,” said Shawn Domagal-Goldman, acting director of the Astrophysics Division at NASA Headquarters in Washington. “As it repeatedly breaks its own records, Webb is also uncovering unknowns for new generations of flagship missions to tackle. Whether it’s following up on the mysteries of dark matter with NASA’s nearly complete Nancy Grace Roman Space Telescope, or narrowing our search for life to Earth-like planets with the Habitable Worlds Observatory, the questions Webb has raised are just as exciting as the answers it’s giving us.”

Star Formation Flex

The progression from a large molecular cloud to massive stars entails multiple steps, some of which are still not well understood by astronomers. Located approximately 4,000 light-years away in the constellation Scorpius, the Cat’s Paw Nebula offers scientists the opportunity to study the turbulent cloud-to-star process in great detail. Webb’s observation of the nebula in near-infrared light builds upon previous studies by NASA’s Hubble and retired Spitzer Space Telescope in visible- and infrared-light, respectively.

With its sharp resolution, Webb shows never-before-seen structural details and features: Massive young stars are carving away at nearby gas and dust, while their bright starlight is producing a bright nebulous glow represented in blue. It’s a temporary scene where the disruptive young stars, with their relatively short lives and luminosity, have a brief but important role in the region’s larger story. As a consequence of these massive stars’ lively behavior, the local star formation process will eventually come to a stop.

Opera House’s Intricate Structure

Start with the toe bean at top center, which is nicknamed the “Opera House” for its circular, tiered-like structure. The primary drivers for the area’s cloudy blue glow are most likely toward its bottom: either the light from the bright yellowish stars or from a nearby source still hidden behind the dense, dark brown dust.

Just below the orange-brown tiers of dust is a bright yellow star with diffraction spikes. While this massive star has carved away at its immediate surroundings, it has been unable to push the gas and dust away to greater distances, creating a compact shell of surrounding material.

Look closely to notice small patches, like the tuning fork-shaped area to the Opera House’s immediate left, that contain fewer stars. These seemingly vacant zones indicate the presence of dense foreground filaments of dust that are home to still-forming stars and block the light of stars in the background.

Spotlight on Stars

Toward the image’s center are small, fiery red clumps scattered amongst the brown dust. These glowing red sources mark regions where massive star formation is underway, albeit in an obscured manner.

Some massive blue-white stars, like the one in the lower left toe bean, seem to be more sharply resolved than others. This is because any intervening material between the star and the telescope has been dissipated by stellar radiation.

Near the bottom of that toe bean are small, dense filaments of dust. These tiny clumps of dust have managed to remain despite the intense radiation, suggesting that they are dense enough to form protostars. A small section of yellow at the right notes the location of a still-enshrouded massive star that has managed to shine through intervening material.

Across this entire scene are many small yellow stars with diffraction spikes. Bright blue-white stars are in the foreground of this Webb image, but some may be a part of the more expansive Cat’s Paw Nebula area.

One eye-catching aspect of this Webb image is the bright, red-orange oval at top right. Its low count of background stars implies it is a dense area just beginning its star-formation process. A couple of visible and still-veiled stars are scattered throughout this region, which are contributing to the illumination of the material in the middle. Some still-enveloped stars leave hints of their presence, like a bow shock at the bottom left, which indicates an energetic ejection of gas and dust from a bright source.

Further explore this subset of toe beans by embarking on a narrated tour or getting closer to the image. We also invite you to reminisce about Webb’s three years of science observations.

The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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 CSA (Canadian Space Agency).




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Abigail Major
Space Telescope Science Institute, Baltimore

Hannah Braun
Space Telescope Science Institute, Baltimore

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Tuesday, January 14, 2025

Jetting into space

An area in the Orion nebula filled with dark, puffy clouds. On the left side a large area of clouds, crossed by a dark bar, is lit up in red and whitish colours by a protostar within. At the other side a large jet of material ejected by the protostar appears, made of thin, wispy, blue and pink clouds. A couple of foreground stars shine brightly in front of the nebula. Credit: ESA/Hubble & NASA, T. Megeath

Today’s NASA/ESA Hubble Space TelescopePicture of the Week peers into the dusty recesses of the nearest massive star-forming region to Earth, the Orion Nebula. Just 1300 light-years away, the Orion Nebula is visible to the naked eye below the three stars that form the ‘belt’ in the constellation Orion. The nebula is home to hundreds of newborn stars including the subject of this image: the protostars HOPS 150 and HOPS 153.

These protostars get their names from the Herschel Orion Protostar Survey, which was carried out with ESA’s Herschel Space Observatory. The object that can be seen in the upper-right corner of this image is HOPS 150: it’s a binary system, two young protostars orbiting each other. Each has a small, dusty disc of material surrounding it that it is feeding from. The dark line that cuts across the bright glow of these protostars is a cloud of gas and dust, over 2 000 times wider than the distance between Earth and the Sun, falling in on the pair of protostars. Based on the amount of infrared versus other wavelengths of light HOPS 150 is emitting, the protostars are mid-way down the path to becoming mature stars.

Extending across the left side of the image is a narrow, colourful outflow called a jet. This jet comes from the nearby protostar HOPS 153, out of frame. HOPS 153 is a significantly younger stellar object than its neighbour, still deeply embedded in its birth nebula and enshrouded by a cloud of cold, dense gas. While Hubble cannot penetrate this gas to see the protostar, the jet HOPS 153 has emitted is brightly visible as it plows into the surrounding gas and dust of the Orion Nebula.

The transition from tightly swaddled protostar to fully fledged star will dramatically affect HOPS 153’s surroundings. As gas falls onto the protostar, its jets spew material and energy into interstellar space, carving out bubbles and heating the gas. By stirring up and warming nearby gas, HOPS 153 may regulate the formation of new stars in its neighbourhood and even slow its own growth.



Wednesday, December 25, 2024

A Baby Star in Action: B335 Offers a Natural Laboratory for Astrochemistry

Fig.1: Time Variation of B335 - (Top) ALMA observations of the continuum. (Middle) ALMA observations of Complex Organic Molecules. (Bottom) Illustrations. Credit: ALMA (ESO/NAOJ/NRAO) / J.-E. Lee et al.

Fig.2: Animation of Time Variation of B335 - (Left) Bolometric luminosity from mid-infrared observations. (Middle) ALMA observations of the continuum. (Right) ALMA observations of Complex Organic Molecules. Credit: J.-E. Lee et al.

Fig.3:  Ilustrations of “Natural Experiment” Around B335
Credit: ALMA (ESO/NAOJ/NRAO) / J.-E. Lee et al.




Scientists have taken an unprecedented step forward in understanding the chemical processes occurring as new stars form, thanks to observations of the variable protostar B335, a very young forming star 537 light years away. Using the high-resolution capabilities of the Atacama Large Millimeter/submillimeter Array (ALMA), researchers tracked the behavior of complex organic molecules (COMs) during a rare burst of brightness, providing a real-time glimpse into the universe's building blocks for life.

Stars grow episodically, with periods of slowly increasing mass interrupted by dramatic events when extra-large amounts of matter land on the star. These events increase the star’s brightness, which heats nearby dust and releases previously frozen COMs into the surrounding gas. However, scientists observed a surprising twist: after the burst ended, the COMs did not refreeze onto the dust as quickly as expected.
“This discovery challenges previous assumptions about the freeze-out timescale of these molecules,” says Jeong-Eun Lee, the lead researcher from Seoul National University. “The prolonged presence of gas-phase COMs reveals the dynamic and complex chemical processes around young stars.”

Thanks to ALMA's unparalleled sensitivity, the study marks the first real-time tracking of molecular changes across a burst cycle. Continuous monitoring of this protostar with ALMA will reveal the timescales for gas cooling, chemical reactions, and interactions between dust grains and gaseous molecules.
Unlike laboratory scientists, astronomers cannot experiment on the cosmos. Remarkably, B335 has performed a “natural experiment” in astrochemistry, showing how the ingredients for life might evolve in stellar nurseries.

“By combining the ALMA results with data from the James Webb Space Telescope (JWST) on the ice component of the COMs in B335, the chemistry of COMs will be fully known,” commented Yao-Lun Yang, another co-author from the RIKEN.




Additional Information

The findings, published in the Astrophysical Journal Letters as “A Natural Laboratory for Astrochemistry, a Variable Protostar B335”, open a new chapter in studying how the building blocks of life form and transform across the cosmos.

The original press release was published by the National Astrónomical Observatory of Japan (NAOJ), an ALMA partner on behalf of East Asia.

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Organisation for Astronomical Research in the Southern Hemisphere (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the National Science and Technology Council (NSTC) in Taiwan, and by NINS in cooperation with the Academia Sinica(AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.



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Tuesday, September 24, 2024

Fireworks at Closest Approach: Repeated X-ray Flares from a Young Binary System

Two young protostars in a cosmic tango that brings them within 10 stellar radii every two weeks. This artist’s illustration of the DQ Tau system shows the intense fireworks that occur every fortnight as these two swiftly moving stars are ever, ever getting back together. Image credit: NASA/JPL-Caltech/R. Hurt (IPAC).

DQ Tau is a unique binary system. Approximately 650 light-years away in the Taurus constellation, DQ Tau consists of two young stars still in the process of forming. The protostars have not yet ignited hydrogen burning in their cores (the fusion process that heats mature stars). Instead, they are glowing as they evolve from their natal form (diffuse clouds of gas) and are heated by this gravitational collapse. Each is half the mass of the Sun and currently twice its radius, dancing in a highly elongated orbit which has them plunging in towards each other every 15.8 days. At closest approach in this violent cosmic tango, the separation between the two stars is exceptionally small, only 8-10 stellar radii. Characteristic of this early phase, the protostars in DQ Tau harbor strong magnetic fields on their surfaces. Also, like most protostars, the DQ Tau system is surrounded by a disk in which planets are also forming. Understanding planet formation, including how the intense flares characteristic of protostars affect disk heating and chemistry, are areas of active research.

DQ Tau provides an exceptional laboratory for such studies. Like clockwork, the DQ Tau system brightens at closest approach. While large X-ray flares in young stars are generally rare and unpredictable (as on our own star, the Sun), the presence of the predictable X-ray super-flares and outbursts in DQ Tau enables synchronized studies of these cosmic fireworks. Like tourists at Yellowstone National Park timing their visit to Old Faithful Geyser, astronomers can plan ahead, coordinating telescopes to jointly investigate these intense flares and understand how they affect the protoplanetary disk. X-ray flares come as the protostar magnetospheres collide, while the lower energy optical and ultraviolet flares also come from accretion of material onto the young stars. Infrared and radio studies probe the changing temperature and chemistry of the protoplanetary disk.

In a recent paper published in the Astrophysical Journal, scientists led by Konstantin Getman at Pennsylvania State University report on new observations of a single orbit of DQ Tau in July and August 2022 using the NuSTAR, Swift, and Chandra X-ray telescopes. NuSTAR accesses higher energy X-rays, while Swift and Chandra access lower energy X-rays. The observations indicate that most of the X-ray emission is from interactions of the magnetospheres of these young stars at closest approach. In a process similar to what is seen on our own Sun, magnetic field collisions and reconnections produce strong high-energy X-ray emission. This heats the surrounding region to high temperature, detectable as thermal emission in the lower energy X-rays. Notably, however, flares on our Sun occur among coronal magnetic loops much smaller than the star, with sizes of 1000 to 10,000 km. In contrast, the DQ Tau super-flares occur on spatial scales a thousand times larger, corresponding to approximately 10 million km or tens of stellar radii. The current study is part of a broader campaign using additional ground-based telescopes to investigate the influence of DQ Tau’s stellar radiation on the chemistry within its surrounding disk.


Monday, September 16, 2024

NASA's Webb Peers into the Extreme Outer Galaxy

NASA’s James Webb Space Telescope observed the outskirts of our Milky Way galaxy. Known as the Extreme Outer Galaxy, this region is located more than 58,000 light-years from the Galactic Center.

To learn more about how a local environment affects the star formation process within it, a team of scientists directed the telescope’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) toward a total of four star-forming areas within Digel Clouds 1 and 2: 1A, 1B, 2N, and 2S.

In the case of Cloud 2S, shown here, Webb revealed a luminous main cluster that contains newly formed stars. Several of these young stars are emitting extended jets of material from their poles. To the main cluster’s top right is a sub-cluster of stars, a feature that scientists previously suspected to exist but has now been confirmed with Webb. Additionally, the telescope revealed a deep sea of background galaxies and red nebulous structures that are being carved away by winds and radiation from nearby stars.

Annotated image of Digel Cloud 2S captured by Webb's NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument), with compass arrows, a scale bar, color key, and graphic overlays for reference.

The north and east compass arrows show the orientation of the image on the sky. Note that the relationship between north and east on the sky (as seen from below) is flipped relative to direction arrows on a map of the ground (as seen from above).

The scale bar is labeled in light-years and arcseconds. One light-year is equal to about 5.88 trillion miles or 9.46 trillion kilometers. One arcsecond is equal to 1/3600 of one degree of arc. (The full Moon has an angular diameter of about 0.5 degrees.) The actual size of an object that covers one arcsecond on the sky depends on its distance from the telescope.

This image shows invisible near- and mid-infrared wavelengths of light that have been translated into visible-light colors. The color key shows which NIRCam and MIRI filters were used when collecting the light. The color of each filter name is the visible light color used to represent the infrared light that passes through that filter.

In the main cluster are five white arrows, which highlight the paths of five protostar jets. To learn more about how a local environment affects the star formation process within it, a team of scientists directed the telescope’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) toward a total of four star-forming areas within Digel Clouds 1 and 2: 1A, 1B, 2N, and 2S.

In the case of Cloud 2S, shown here, Webb revealed a luminous main cluster that contains newly formed stars. Several of these young stars are emitting extended jets of material from their poles. To the main cluster’s top right is a sub-cluster of stars, a feature that scientists previously suspected to exist but has now been confirmed with Webb. Additionally, the telescope revealed a deep sea of background galaxies and red nebulous structures that are being carved away by winds and radiation from nearby stars. Credits: Image: NASA, ESA, CSA, STScI, Michael Ressler (NASA-JPL)



Astronomers have directed NASA’s James Webb Space Telescope to examine the outskirts of our Milky Way galaxy. Scientists call this region the Extreme Outer Galaxy due to its location more than 58,000 light-years away from the Galactic Center. (For comparison, Earth is approximately 26,000 light-years from the center.)

A team of scientists used Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to image select regions within two molecular clouds known as Digel Clouds 1 and 2. With its high degree of sensitivity and sharp resolution, the Webb data resolved these areas, which are hosts to star clusters undergoing bursts of star formation, in unprecedented detail. Details of this data include components of the clusters such as very young (Class 0) protostars, outflows and jets, and distinctive nebular structures.

These Webb observations, which came from telescope time allocated to Mike Ressler of NASA’s Jet Propulsion Laboratory in California, are enabling scientists to study star formation in the outer Milky Way in the same depth of detail as observations of star formation in our own solar neighborhood.

“In the past, we knew about these star forming regions but were not able to delve into their properties,” said Natsuko Izumi of Gifu University and the National Astronomical Observatory of Japan, lead author of the study. “The Webb data builds upon what we have incrementally gathered over the years from prior observations with different telescopes and observatories. We can get very powerful and impressive images of these clouds with Webb. In the case of Digel Cloud 2, I did not expect to see such active star formation and spectacular jets.”

Stars in the Making

Although the Digel Clouds are within our galaxy, they are relatively poor in elements heavier than hydrogen and helium. This composition makes them similar to dwarf galaxies and our own Milky Way in its early history. Therefore, the team took the opportunity to use Webb to capture the activity occurring in four clusters of young stars within Digel Clouds 1 and 2: 1A, 1B, 2N, and 2S.

For Cloud 2S, Webb captured the main cluster containing young, newly formed stars. This dense area is quite active as several stars are emitting extended jets of material along their poles. Additionally, while scientists previously suspected a sub-cluster might be present within the cloud, Webb’s imaging capabilities confirmed its existence for the first time.

“We know from studying other nearby star-forming regions that as stars form during their early life phase, they start emitting jets of material at their poles,” said Ressler, second author of the study and principal investigator of the observing program. “What was fascinating and astounding to me from the Webb data is that there are multiple jets shooting out in all different directions from this cluster of stars. It’s a little bit like a firecracker, where you see things shooting this way and that.”

The Saga of Stars

The Webb imagery skims the surface of the Extreme Outer Galaxy and the Digel Clouds, and is just a starting point for the team. They intend to revisit this outpost in the Milky Way to find answers to a variety of current mysteries, including the relative abundance of stars of various masses within Extreme Outer Galaxy star clusters. This measurement can help astronomers understand how a particular environment can influence different types of stars during their formation.

“I’m interested in continuing to study how star formation is occurring in these regions. By combining data from different observatories and telescopes, we can examine each stage in the evolution process,” said Izumi. “We also plan to investigate circumstellar disks within the Extreme Outer Galaxy. We still don’t know why their lifetimes are shorter than in star-forming regions much closer to us. And of course, I’d like to understand the kinematics of the jets we detected in Cloud 2S.”

Though the story of star formation is complex and some chapters are still shrouded in mystery, Webb is gathering clues and helping astronomers unravel this intricate tale.

These findings have been published in the Astronomical Journal.

The observations were taken as part of Guaranteed Time Observation program 1237.

The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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 CSA (Canadian Space Agency).




About This Release

Credits:

Media Contact:

Abigail Major
Space Telescope Science Institute, Baltimore, Maryland

Christine Pulliam
Space Telescope Science Institute, Baltimore, Maryland

Permissions: Content Use Policy

Contact Us: Direct inquiries to the News Team.


Tuesday, July 30, 2024

Outflows from Baby Stars

IRAS 16253–2429 - B335

In stellar nurseries throughout the Milky Way, baby stars swaddled in dusty blankets are growing rapidly and shaping their birth environments. Recently, a research team led by Samuel Federman (University of Toledo) used JWST to investigate the behavior of five young protostars, two of which are shown in the image above. The new JWST images capture the squalls of protostars in their earliest stages, about which relatively little is known. During these early stages, protostars are swathed in dense, dusty envelopes of gas that fall onto the star, spurring rapid growth through accretion. The accretion, in turn, powers narrow outflowing jets and wide outflowing winds that carve out a cavity in the surrounding envelope, creating the characteristic hourglass shapes in the images above. For more information and a closer look at all of the protostars in the sample, be sure to check out the full research article linked below.

By Kerry Hensley

Citation

“Investigating Protostellar Accretion-driven Outflows across the Mass Spectrum: JWST NIRSpec Integral Field Unit 3–5 μm Spectral Mapping of Five Young Protostars,” Samuel A. Federman et al 2024 ApJ 966 41. doi:10.3847/1538-4357/ad2fa0



Friday, June 28, 2024

Pillars of Creation Star in New Visualization from NASA's Hubble and Webb Telescopes

Pillars of Creation Visualization
Credits: Visualization: Greg Bacon (STScI), Ralf Crawford (STScI), Joseph DePasquale (STScI), Leah Hustak (STScI), Christian Nieves (STScI), Joseph Olmsted (STScI), Alyssa Pagan (STScI), Frank Summers (STScI), NASA's Universe of Learning

Pillars of Creation 3D Model
Credits: 3D Model (Leah Hustak (STScI), Ralf Crawford (STScI), NASA's Universe of Learning




Made famous in 1995 by NASA's Hubble Space Telescope, the Pillars of Creation in the heart of the Eagle Nebula have captured imaginations worldwide with their arresting, ethereal beauty.

Now, NASA has released a new 3D visualization of these towering celestial structures using data from NASA's Hubble and James Webb space telescopes. This is the most comprehensive and detailed multiwavelength movie yet of these star-birthing clouds.

"By flying past and amongst the pillars, viewers experience their three-dimensional structure and see how they look different in the Hubble visible-light view versus the Webb infrared-light view," explained principal visualization scientist Frank Summers of the Space Telescope Science Institute (STScI) in Baltimore, who led the movie development team for NASA's Universe of Learning. "The contrast helps them understand why we have more than one space telescope to observe different aspects of the same object."

The four Pillars of Creation, made primarily of cool molecular hydrogen and dust, are being eroded by the fierce winds and punishing ultraviolet light of nearby hot, young stars. Finger-like structures larger than the solar system protrude from the tops of the pillars. Within these fingers can be embedded, embryonic stars. The tallest pillar stretches across three light-years, three-quarters of the distance between our Sun and the next nearest star.

The movie takes visitors into the three-dimensional structures of the pillars. Rather than an artistic interpretation, the video is based on observational data from a science paper led by Anna McLeod, an associate professor at the University of Durham in the United Kingdom. McLeod also served as a scientific advisor on the movie project.

"The Pillars of Creation were always on our minds to create in 3D. Webb data in combination with Hubble data allowed us to see the Pillars in more complete detail," said production lead Greg Bacon of STScI. "Understanding the science and how to best represent it allowed our small, talented team to meet the challenge of visualizing this iconic structure."

The new visualization helps viewers experience how two of the world's most powerful space telescopes work together to provide a more complex and holistic portrait of the pillars. Hubble sees objects that glow in visible light, at thousands of degrees. Webb's infrared vision, which is sensitive to cooler objects with temperatures of just hundreds of degrees, pierces through obscuring dust to see stars embedded in the pillars.

"When we combine observations from NASA's space telescopes across different wavelengths of light, we broaden our understanding of the universe," said Mark Clampin, Astrophysics Division director at NASA Headquarters in Washington. "The Pillars of Creation region continues to offer us new insights that hone our understanding of how stars form. Now, with this new visualization, everyone can experience this rich, captivating landscape in a new way."

Produced for NASA by STScI with partners at Caltech/IPAC, and developed by the AstroViz Project of NASA's Universe of Learning, the 3D visualization is part of a longer, narrated video that combines a direct connection to the science and scientists of NASA's Astrophysics missions with attention to the needs of an audience of youth, families, and lifelong learners. It enables viewers to explore fundamental questions in science, experience how science is done, and discover the universe for themselves.

Several stages of star formation are highlighted in the visualization. As viewers approach the central pillar, they see at its top an embedded, infant protostar glimmering bright red in infrared light. Near the top of the left pillar is a diagonal jet of material ejected from a newborn star. Though the jet is evidence of star birth, viewers can't see the star itself. Finally, at the end of one of the left pillar's protruding "fingers" is a blazing, brand-new star.

A bonus product from this visualization is a new 3D printable model of the Pillars of Creation. The base model of the four pillars used in the visualization has been adapted to the STL file format, so that viewers can download the model file and print it out on 3D printers. Examining the structure of the pillars in this tactile and interactive way adds new perspectives and insights to the overall experience.

More visualizations and connections between the science of nebulas and learners can be explored through other products produced by NASA's Universe of Learning such as ViewSpace , a video exhibit that is currently running at almost 200 museums and planetariums across the United States. Visitors can go beyond video to explore the images produced by space telescopes with interactive tools now available for museums and planetariums.

NASA's Universe of Learning materials are based upon work supported by NASA under award number NNX16AC65A to the Space Telescope Science Institute, working in partnership with Caltech/IPAC, Pasadena, California, Center for Astrophysics | Harvard & Smithsonian, Cambridge, Massachusetts, and Jet Propulsion Laboratory, La Cañada Flintridge, California.

The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, Colorado, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, Maryland, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.

The James Webb Space Telescope is the world's premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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 CSA (Canadian Space Agency).

NASA's Universe of Learning is part of the NASA Science Activation program, from the Science Mission Directorate at NASA Headquarters. The Science Activation program connects NASA science experts, real content and experiences, and community leaders in a way that activates minds and promotes deeper understanding of our world and beyond. Using its direct connection to the science and the experts behind the science, NASA's Universe of Learning provides resources and experiences that enable youth, families, and lifelong learners to explore fundamental questions in science, experience how science is done, and discover the universe for themselves.




About This Release

Credits:

Media Contact:

Ann Jenkins
Space Telescope Science Institute, Baltimore, Maryland

Christine Pulliam
Space Telescope Science Institute, Baltimore, Maryland

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Content Use Policy

Contact Us: Direct inquiries to the News Team.

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Wednesday, March 13, 2024

Cheers! NASA's Webb Finds Ethanol, Other Icy Ingredients for Worlds

Parallel Field to Protostar IRAS 23385 (MIRI Image)
Credits: Image: NASA, ESA, CSA, W.R.M. Rocha (LEI)

Complex Organic Molecules of NGC 1333 IRAS 2A Protostar (MIRI)
Credits: Illustration: NASA, ESA, CSA, Leah Hustak (STScI)




What do margaritas, vinegar, and ant stings have in common? They contain chemical ingredients that NASA’s James Webb Space Telescope has identified surrounding two young protostars known as IRAS 2A and IRAS 23385. Although planets are not yet forming around those stars, these and other molecules detected there by Webb represent key ingredients for making potentially habitable worlds.

An international team of astronomers used Webb’s MIRI (Mid-Infrared Instrument) to identify a variety of icy compounds made up of complex organic molecules like ethanol (alcohol) and likely acetic acid (an ingredient in vinegar). This work builds on previous Webb detections of diverse ices in a cold, dark molecular cloud.

“This finding contributes to one of the long-standing questions in astrochemistry,” said team leader Will Rocha of Leiden University in the Netherlands. “What is the origin of complex organic molecules, or COMs, in space? Are they made in the gas phase or in ices? The detection of COMs in ices suggests that solid-phase chemical reactions on the surfaces of cold dust grains can build complex kinds of molecules.”

As several COMs, including those detected in the solid phase in this research, were previously detected in the warm gas phase, it is now believed that they originate from the sublimation of ices. Sublimation is to change directly from a solid to a gas without becoming a liquid. Therefore, detecting COMs in ices makes astronomers hopeful about improved understanding of the origins of other, even larger molecules in space.

Scientists are also keen to explore to what extent these COMs are transported to planets at much later stages of protostellar evolution. COMs in cold ices are thought to be easier to transport from molecular clouds to planet-forming disks than warm, gaseous molecules. These icy COMs can therefore be incorporated into comets and asteroids, which in turn may collide with forming planets, delivering the ingredients for life to possibly flourish.

The science team also detected simpler molecules, including formic acid (which causes the burning sensation of an ant sting), methane, formaldehyde, and sulfur dioxide. Research suggests that sulfur-containing compounds like sulfur dioxide played an important role in driving metabolic reactions on the primitive Earth.

Of particular interest is that one of the sources investigated, IRAS 2A, is characterized as a low-mass protostar. IRAS 2A may therefore be similar to the early stages of our own solar system. As such, the chemicals identified around this protostar were likely present in the first stages of development of our solar system and later delivered to the primitive Earth.

“All of these molecules can become part of comets and asteroids and eventually new planetary systems when the icy material is transported inward to the planet-forming disk as the protostellar system evolves,” said Ewine van Dishoeck of Leiden University, one of the coordinators of the science program. “We look forward to following this astrochemical trail step-by-step with more Webb data in the coming years.”

These observations were made for the JOYS+ (James Webb Observations of Young ProtoStars) program. The team dedicated these results to team member Harold Linnartz, who unexpectedly passed away in December 2023, shortly after the acceptance of this paper.

This research has been accepted for publication in the journal Astronomy & Astrophysics.

The James Webb Space Telescope is the world's premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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.




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Friday, September 15, 2023

NASA's Webb Snaps Supersonic Outflow of Young Star

HH 211 (NIRCam Image)
Credits: Image: ESA/Webb, NASA, CSA, Tom Ray (Dublin)




Herbig-Haro (HH) objects are luminous regions surrounding newborn stars, formed when stellar winds or jets of gas spewing from these newborn stars form shock waves colliding with nearby gas and dust at high speeds. This image of HH 211 from NASA’s James Webb Space Telescope reveals an outflow from a Class 0 protostar, an infantile analog of our Sun when it was no more than a few tens of thousands of years old and with a mass only 8% of the present-day Sun. (It will eventually grow into a star like the Sun.)

Infrared imaging is powerful in studying newborn stars and their outflows, because such stars are invariably still embedded within the gas from the molecular cloud in which they formed. The infrared emission of the star’s outflows penetrates the obscuring gas and dust, making a Herbig-Haro object like HH 211 ideal for observation with Webb’s sensitive infrared instruments. Molecules excited by the turbulent conditions, including molecular hydrogen, carbon monoxide, and silicon monoxide, emit infrared light that Webb can collect to map out the structure of the outflows.

The image showcases a series of bow shocks to the southeast (lower-left) and northwest (upper-right) as well as the narrow bipolar jet that powers them. Webb reveals this scene in unprecedented detail — roughly 5 to 10 times higher spatial resolution than any previous images of HH 211. The inner jet is seen to “wiggle” with mirror symmetry on either side of the central protostar. This is in agreement with observations on smaller scales and suggests that the protostar may in fact be an unresolved binary star.

Earlier observations of HH 211 with ground-based telescopes revealed giant bow shocks moving away from us (northwest) and moving towards us (southeast) and cavity-like structures in shocked hydrogen and carbon monoxide respectively, as well as a knotty and wiggling bipolar jet in silicon monoxide. Researchers have used Webb’s new observations to determine that the object’s outflow is relatively slow in comparison to more evolved protostars with similar types of outflows.

The team measured the velocities of the innermost outflow structures to be roughly 48-60 miles per second (80 to 100 kilometers per second). However, the difference in velocity between these sections of the outflow and the leading material they’re colliding with — the shock wave — is much smaller. The researchers concluded that outflows from the youngest stars, like that in the center of HH 211, are mostly made up of molecules, because the comparatively low shock wave velocities are not energetic enough to break the molecules apart into simpler atoms and ions.

The James Webb Space Telescope is the world's premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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




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Monday, July 31, 2023

Webb Snaps Highly Detailed Infrared Image of Actively Forming Stars

Herbig-Haro 46/47 (NIRCam Image)
Credits: Image: NASA, ESA, CSA
Image Processing: Joseph DePasquale (STScI)




Young stars are rambunctious!

NASA’s James Webb Space Telescope has captured the “antics” of a pair of actively forming young stars, known as Herbig-Haro 46/47, in high-resolution near-infrared light. To find them, trace the bright pink and red diffraction spikes until you hit the center: The stars are within the orange-white splotch. They are buried deeply in a disk of gas and dust that feeds their growth as they continue to gain mass. The disk is not visible, but its shadow can be seen in the two dark, conical regions surrounding the central stars.

The most striking details are the two-sided lobes that fan out from the actively forming central stars, represented in fiery orange. Much of this material was shot out from those stars as they repeatedly ingest and eject the gas and dust that immediately surround them over thousands of years.

When material from more recent ejections runs into older material, it changes the shape of these lobes. This activity is like a large fountain being turned on and off in rapid, but random succession, leading to billowing patterns in the pool below it. Some jets send out more material and others launch at faster speeds. Why? It’s likely related to how much material fell onto the stars at a particular point in time.

The stars’ more recent ejections appear in a thread-like blue. They run just below the red horizontal diffraction spike at 2 o’clock. Along the right side, these ejections make clearer wavy patterns. They are disconnected at points, and end in a remarkable uneven light purple circle in the thickest orange area. Lighter blue, curly lines also emerge on the left, near the central stars, but are sometimes overshadowed by the bright red diffraction spike.

All of these jets are crucial to star formation itself. Ejections regulate how much mass the stars ultimately gather. (The disk of gas and dust feeding the stars is small. Imagine a band tightly tied around the stars.)

Now, turn your eye to the second most prominent feature: the effervescent blue cloud. This is a region of dense dust and gas, known both as a nebula and more formally as a Bok globule. When viewed mainly in visible light, it appears almost completely black – only a few background stars peek through. In Webb’s crisp near-infrared image, we can see into and through the gauzy layers of this cloud, bringing a lot more of Herbig-Haro 46/47 into focus, while also revealing a deep range of stars and galaxies that lie well beyond it. The nebula’s edges appear in a soft orange outline, like a backward L along the right and bottom.

This nebula is significant – its presence influences the shapes of the jets shot out by the central stars. As ejected material rams into the nebula on the lower left, there is more opportunity for the jets to interact with molecules within the nebula, causing them both to light up.

There are two other areas to look at to compare the asymmetry of the two lobes. Glance toward the upper right to pick out a blobby, almost sponge-shaped ejecta that appears separate from the larger lobe. Only a few threads of semi-transparent wisps of material point toward the larger lobe. Almost transparent, tentacle-like shapes also appear to be drifting behind it, like streamers in a cosmic wind. In contrast, at lower left, look beyond the hefty lobe to find an arc. Both are made up of material that was pushed the farthest and possibly by earlier ejections. The arcs appear to be pointed in different directions, and may have originated from different outflows.

Take another long look at this image. Although it appears Webb has snapped Herbig-Haro 46/47 edge-on, one side is angled slightly closer to Earth. Counterintuitively, it’s the smaller right half. Though the left side is larger and brighter, it is pointing away from us.

Over millions of years, the stars in Herbig-Haro 46/47 will fully form – clearing the scene of these fantastic, multihued ejections, allowing the binary stars to take center stage against a galaxy-filled background.

Webb can reveal so much detail in Herbig-Haro 46/47 for two reasons. The object is relatively close to Earth, and Webb’s image is made up of several exposures, which adds to its depth.

Herbig-Haro 46/47 lies only 1,470 light-years away in the Vela Constellation.

The James Webb Space Telescope is the world's premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing 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.




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Sunday, July 16, 2023

ALMA Digs Deeper into the Mystery of Planet Formation


Images of disks around 19 protostars, including 4 binary systems observed with ALMA. For 1 binary system, disks around the primary and secondary are presented independently (2nd line rightmost and 3rd line leftmost). Disks are presented in the order of their evolutionary sequence (the one in the upper-left corner is the youngest while the one at the lower-right corner is the oldest). The two oldest disks show faint ring-gap structures. A scale bar of 20 au (roughly the distance between the Sun and Uranus) is shown for each disk image. (Credit: ALMA (ESO/NAOJ/NRAO), N. Ohashi et al.)
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An international research team used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe disks around 19 protostars with a very high resolution to search for the earliest signs of planet formation. This survey was motivated by the recent findings that planet formation may be well-underway in the more-evolved proto-planetary disks, but until now there had been no systematic study to search for signs of planet formation in younger protostellar systems.

Planets form in a disk around a newborn star. These ‘proto-planetary’ disks only last a few million years, meaning that a forming planetary system only has this amount of time to finish its formation. However, it is still not clear just how rapidly planet formation begins within these disks. Recent ALMA observations have revealed that many proto-planetary disks have substructures such as gaps and rings, indicating that planets are already forming from the disk. “These previous results motivated us to examine even younger disks around protostars to answer the question, at what stage of star formation do planet forms,” says Nagayoshi Ohashi at Academia Sinica Institute of Astronomy and Astrophysics (ASIAA, Taiwan), who led the team.

The team observed disks around 19 protostars located within about 650 light-years from the Earth. This is the first systematic study to investigate the detailed structure of disks around a large sample of protostars with high angular resolution. The observations clearly show that the disks around protostars are different from more-evolved proto-planetary disks. Among the 19 protostars, rings, and gaps, which are signs of planet formation, were observed only in a few disks. Moreover, the ring structures are less distinct than those seen in the proto-planetary disks.

“We did not expect to see such clear differences between disks around protostars and more-evolved disks,” says Ohashi. John Tobin, a Co-PI of the program at the National Radio Astronomical Observatory (USA) adds “Our results suggest that disks around protostars are not fully ready for planet formation. We believe that the actual formation of the planetary system progresses rapidly in the 100,000 years to 1,000,000 years after star formation begins.”

This research was detailed in Nagayoshi Ohashi et al. “Early Planet Formation in Embedded Disks (eDisk). I. Overview of the Program and First Results” and 3 other papers (Lin et al., van 't Hoff et al., Yamato et al.) published on June 28, 2023 in the Astrophysical Journal, and one paper accepted for later publication in the same journal (Kido et al.).

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Monday, January 16, 2023

NASA’s Webb Uncovers Star Formation in Cluster’s Dusty Ribbons

NGC 346 (NIRCam Image)
Credits: Science: NASA, ESA, CSA, Olivia C. Jones (UK ATC), Guido De Marchi (ESTEC), Margaret Meixner (USRA)
Image Processing: Alyssa Pagan (STScI), Nolan Habel (USRA), Laura Lenkić (USRA), Laurie E. U. Chu (NASA Ames)




NGC 346, one of the most dynamic star-forming regions in nearby galaxies, is full of mystery. Now, it is less mysterious with new findings from NASA’s James Webb Space Telescope. 

NCG 346 is located in the Small Magellanic Cloud (SMC), a dwarf galaxy close to our Milky Way. The SMC contains lower concentrations of elements heavier than hydrogen or helium, which astronomers call metals, compared to the Milky Way. Since dust grains in space are composed mostly of metals, scientists expected there would be low amounts of dust, and that it would be hard to detect. New data from Webb reveals the opposite.

Astronomers probed this region because the conditions and amount of metals within the SMC resemble those seen in galaxies billions of years ago, during an era in the universe known as “cosmic noon,” when star formation was at its peak. Some 2 to 3 billion years after the big bang, galaxies were forming stars at a furious rate. The fireworks of star formation happening then still shape the galaxies we see around us today.

“A galaxy during cosmic noon wouldn’t have one NGC 346 like the Small Magellanic Cloud does; it would have thousands” of star-forming regions like this one, said Margaret Meixner, an astronomer at the Universities Space Research Association and principal investigator of the research team. “But even if NGC 346 is now the one and only massive cluster furiously forming stars in its galaxy, it offers us a great opportunity to probe conditions that were in place at cosmic noon.” 

By observing protostars still in the process of forming, researchers can learn if the star formation process in the SMC is different from what we observe in our own Milky Way. Previous infrared studies of NGC 346 have focused on protostars heavier than about 5 to 8 times the mass of our Sun. “With Webb, we can probe down to lighter-weight protostars, as small as one tenth of our Sun, to see if their formation process is affected by the lower metal content,” said Olivia Jones of the United Kingdom Astronomy Technology Centre, Royal Observatory Edinburgh, a co-investigator on the program.

As stars form, they gather gas and dust, which can look like ribbons in Webb imagery, from the surrounding molecular cloud. The material collects into an accretion disk that feeds the central protostar. Astronomers have detected gas around protostars within NGC 346, but Webb’s near-infrared observations mark the first time they have also detected dust in these disks.

“We’re seeing the building blocks, not only of stars, but also potentially of planets,” said Guido De Marchi of the European Space Agency, a co-investigator on the research team. “And since the Small Magellanic Cloud has a similar environment to galaxies during cosmic noon, it’s possible that rocky planets could have formed earlier in the universe than we might have thought.”

The team also has spectroscopic observations from Webb’s NIRSpec instrument that they are continuing to analyze. These data are expected to provide new insights into the material accreting onto individual protostars, as well as the environment immediately surrounding the protostar.

These results are being presented Jan. 11 in a press conference at the 241st meeting of the American Astronomical Society. The observations were obtained as part of program 1227.

  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.




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Wednesday, November 16, 2022

NASA’s Webb Catches Fiery Hourglass as New Star Forms

L1527 and Protostar (NIRCam Image)
Credits: Science: NASA, ESA, CSA, STScI
Image Processing: Joseph DePasquale (STScI), Alyssa Pagan (STScI), Anton M. Koekemoer (STScI)





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 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.



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Friday, July 22, 2022

Can Shock Waves Create the Conditions for Molecule Formation?

This infrared image from the Spitzer Space Telescope shows the dark, dusty cloud Lynds 1157, which hosts young protostars

Credit:NASA/JPL-Caltech/UIUC

The dark, dusty clouds surrounding young, hot protostars are the sites of molecule formation. What can new radio observations tell us about the potential for molecule formation in the shocked surroundings of a nearby protostar system?


A visible-light image of the interstellar dark cloud Lynds 1157. Infrared or radio observations are needed to reveal the young stars hidden by the dust. Credit:
NASA/JPL-Caltech/AURA

Making Molecules

Over the past century, astronomers have discovered more than a hundred kinds of molecules in space. Exactly how these molecules form and survive in the cold, tenuous gas of the interstellar medium is an active area of research. One of several ways that molecules are thought to form is in the wake of a shock wave, which condenses and warms the interstellar medium, helping lone atoms link up in the vastness of space.

Shock waves can be produced by outflows from newly forming stars called protostars, which are still wrapped in dense clouds of gas and dust. Luckily, infrared and radio observations allow us to draw back this dusty curtain and peer into the birthplaces of young stars and watch as they collect gas and shoot out jets of material. In a new publication, a team led by Siyi Feng (冯思轶) from Xiamen University presents new radio data that probes the surroundings of a young protostellar system at the heart of the dark cloud Lynds 1157 — one of the best places to study how shocks impact interstellar chemistry.


Example maps of an outflowing jet from Lynds 1157 in two emission lines of ammonia. The shocks are located at the places labeled B0, B1, and B2, while smaller structures are labeled with additional letters. The protobinary is labeled “mm.” Credit:
Adapted from Feng et al. 2022

Peering at Protostars

Previous observations of Lynds 1157 have shown that the region hosts organic molecules like methanol and cyanoacetylene — a clear sign of ongoing interstellar chemistry. What makes the region especially interesting is the series of shocks that have formed along a jet that flows outward from the central source, which is likely a protobinary system. Observations show that the outermost shock is 1,000 years old, while the inner shocks are younger, allowing us to study how the temperature and density of the gas changed over time as the shocks passed through.

Using the Karl G. Jansky Very Large Array, Feng and collaborators observed emission lines of ammonia (NH3) to make high-resolution maps of Lynds 1157 and measure how the temperature and density of the gas vary throughout the cloud.


Maps of the mean temperature (left), density (center), and ratio of ammonia molecules in an excited state to those in an unexcited state (right).
  Adapted from Feng et al. 2022

Studying Shocks

The ammonia emission lines trace the jet as it moves outward from the central protobinary, and the observations show that the gas is warmest close to the protobinary, cooler farther out along the jet, and densest at the locations of the shocks. And at the locations of the shocks, the team found evidence for ammonia molecules in an excited state, a clear indication that the gas has been heated by the shocks.

The team’s observations show that the passage of shocks heated and compressed the gas, and that as the shocks moved outward, the gas cooled. This illustrates that shocks can provide the warm, dense environment needed for molecules to form. The measurements made in this work should enable detailed chemical modeling, allowing for an even better understanding of how shocks have transformed the gas around these young protostars and paved the way for molecule formation.

Citation

“A Detailed Temperature Map of the Archetypal Protostellar Shocks in L1157,” S. Feng et al 2022 ApJL 933 L35. doi:10.3847/2041-8213/ac75d7