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Euclid Quick Data Release (Q1). First detections from the galaxy cluster workflow

Galaxy Evolution and AGN - Wed, 26/03/2025 - 10:43
arXiv:2503.19196v1 Announce Type: new Abstract: The first survey data release by the Euclid mission covers approximately $63\,\mathrm{deg^2}$ in the Euclid Deep Fields to the same depth as the Euclid Wide Survey. This paper showcases, for the first time, the performance of cluster finders on Euclid data and presents examples of validated clusters in the Quick Release 1 (Q1) imaging data. We identify clusters using two algorithms (AMICO and PZWav) implemented in the Euclid cluster-detection pipeline. We explore the internal consistency of detections from the two codes, and cross-match detections with known clusters from other surveys using external multi-wavelength and spectroscopic data sets. This enables assessment of the Euclid photometric redshift accuracy and also of systematics such as mis-centring between the optical cluster centre and centres based on X-ray and/or Sunyaev--Zeldovich observations. We report 426 joint PZWav and AMICO-detected clusters with high signal-to-noise ratios over the full Q1 area in the redshift range $0.2 \leq z \leq 1.5$. The chosen redshift and signal-to-noise thresholds are motivated by the photometric quality of the early Euclid data. We provide richness estimates for each of the Euclid-detected clusters and show its correlation with various external cluster mass proxies. Out of the full sample, 77 systems are potentially new to the literature. Overall, the Q1 cluster catalogue demonstrates a successful validation of the workflow ahead of the Euclid Data Release 1, based on the consistency of internal and external properties of Euclid-detected clusters.

Euclid Quick Data Release (Q1). First detections from the galaxy cluster workflow

Recent IoA Publications - Wed, 26/03/2025 - 10:43
arXiv:2503.19196v1 Announce Type: new Abstract: The first survey data release by the Euclid mission covers approximately $63\,\mathrm{deg^2}$ in the Euclid Deep Fields to the same depth as the Euclid Wide Survey. This paper showcases, for the first time, the performance of cluster finders on Euclid data and presents examples of validated clusters in the Quick Release 1 (Q1) imaging data. We identify clusters using two algorithms (AMICO and PZWav) implemented in the Euclid cluster-detection pipeline. We explore the internal consistency of detections from the two codes, and cross-match detections with known clusters from other surveys using external multi-wavelength and spectroscopic data sets. This enables assessment of the Euclid photometric redshift accuracy and also of systematics such as mis-centring between the optical cluster centre and centres based on X-ray and/or Sunyaev--Zeldovich observations. We report 426 joint PZWav and AMICO-detected clusters with high signal-to-noise ratios over the full Q1 area in the redshift range $0.2 \leq z \leq 1.5$. The chosen redshift and signal-to-noise thresholds are motivated by the photometric quality of the early Euclid data. We provide richness estimates for each of the Euclid-detected clusters and show its correlation with various external cluster mass proxies. Out of the full sample, 77 systems are potentially new to the literature. Overall, the Q1 cluster catalogue demonstrates a successful validation of the workflow ahead of the Euclid Data Release 1, based on the consistency of internal and external properties of Euclid-detected clusters.

NASA’s Webb Captures Neptune’s Auroras For First Time

Astronomy News - Wed, 26/03/2025 - 10:28
6 Min Read NASA’s Webb Captures Neptune’s Auroras For First Time At the left, an enhanced-color image of Neptune from NASA’s Hubble Space Telescope. At the right, that image is combined with data from NASA’s James Webb Space Telescope. Credits:
NASA, ESA, CSA, STScI, Heidi Hammel (AURA), Henrik Melin (Northumbria University), Leigh Fletcher (University of Leicester), Stefanie Milam (NASA-GSFC)

Long-sought auroral glow finally emerges under Webb’s powerful gaze

For the first time, NASA’s James Webb Space Telescope has captured bright auroral activity on Neptune. Auroras occur when energetic particles, often originating from the Sun, become trapped in a planet’s magnetic field and eventually strike the upper atmosphere. The energy released during these collisions creates the signature glow.

In the past, astronomers have seen tantalizing hints of auroral activity on Neptune, for example, in the flyby of NASA’s Voyager 2 in 1989. However, imaging and confirming the auroras on Neptune has long evaded astronomers despite successful detections on Jupiter, Saturn, and Uranus. Neptune was the missing piece of the puzzle when it came to detecting auroras on the giant planets of our solar system.

“Turns out, actually imaging the auroral activity on Neptune was only possible with Webb’s near-infrared sensitivity,” said lead author Henrik Melin of Northumbria University, who conducted the research while at the University of Leicester. “It was so stunning to not just see the auroras, but the detail and clarity of the signature really shocked me.”

The data was obtained in June 2023 using Webb’s Near-Infrared Spectrograph. In addition to the image of the planet, astronomers obtained a spectrum to characterize the composition and measure the temperature of the planet’s upper atmosphere (the ionosphere). For the first time, they found an extremely prominent emission line signifying the presence of the trihydrogen cation (H3+), which can be created in auroras. In the Webb images of Neptune, the glowing aurora appears as splotches represented in cyan.

Image A:
Neptune’s Auroras – Hubble and Webb At the left, an enhanced-color image of Neptune from NASA’s Hubble Space Telescope. At the right, that image is combined with data from NASA’s James Webb Space Telescope. The cyan splotches, which represent auroral activity, and white clouds, are data from Webb’s Near-Infrared Spectrograph (NIRSpec), overlayed on top of the full image of the planet from Hubble’s Wide Field Camera 3. NASA, ESA, CSA, STScI, Heidi Hammel (AURA), Henrik Melin (Northumbria University), Leigh Fletcher (University of Leicester), Stefanie Milam (NASA-GSFC)

“H3+ has a been a clear signifier on all the gas giants — Jupiter, Saturn, and Uranus — of auroral activity, and we expected to see the same on Neptune as we investigated the planet over the years with the best ground-based facilities available,” explained Heidi Hammel of the Association of Universities for Research in Astronomy, Webb interdisciplinary scientist and leader of the Guaranteed Time Observation program for the Solar System in which the data were obtained. “Only with a machine like Webb have we finally gotten that confirmation.”

The auroral activity seen on Neptune is also noticeably different from what we are accustomed to seeing here on Earth, or even Jupiter or Saturn. Instead of being confined to the planet’s northern and southern poles, Neptune’s auroras are located at the planet’s geographic mid-latitudes — think where South America is located on Earth.

This is due to the strange nature of Neptune’s magnetic field, originally discovered by Voyager 2 in 1989 which is tilted by 47 degrees from the planet’s rotation axis. Since auroral activity is based where the magnetic fields converge into the planet’s atmosphere, Neptune’s auroras are far from its rotational poles.

The ground-breaking detection of Neptune’s auroras will help us understand how Neptune’s magnetic field interacts with particles that stream out from the Sun to the distant reaches of our solar system, a totally new window in ice giant atmospheric science.

From the Webb observations, the team also measured the temperature of the top of Neptune’s atmosphere for the first time since Voyager 2’s flyby. The results hint at why Neptune’s auroras remained hidden from astronomers for so long.

“I was astonished — Neptune’s upper atmosphere has cooled by several hundreds of degrees,” Melin said. “In fact, the temperature in 2023 was just over half of that in 1989.” 

Through the years, astronomers have predicted the intensity of Neptune’s auroras based on the temperature recorded by Voyager 2. A substantially colder temperature would result in much fainter auroras. This cold temperature is likely the reason that Neptune’s auroras have remained undetected for so long. The dramatic cooling also suggests that this region of the atmosphere can change greatly even though the planet sits over 30 times farther from the Sun compared to Earth.
Equipped with these new findings, astronomers now hope to study Neptune with Webb over a full solar cycle, an 11-year period of activity driven by the Sun’s magnetic field. Results could provide insights into the origin of Neptune’s bizarre magnetic field, and even explain why it’s so tilted.

“As we look ahead and dream of future missions to Uranus and Neptune, we now know how important it will be to have instruments tuned to the wavelengths of infrared light to continue to study the auroras,” added Leigh Fletcher of Leicester University, co-author on the paper. “This observatory has finally opened the window onto this last, previously hidden ionosphere of the giant planets.”

These observations, led by Fletcher, were taken as part of Hammel’s Guaranteed Time Observation program 1249. The team’s results have been published in Nature Astronomy.

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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Media Contacts

Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Hannah Braun- hbraun@stsci.edu
Space Telescope Science Institute, Baltimore, Maryland

Christine Pulliamcpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.

Science

Henrik Melin (Northumbria University)

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Share Details Last Updated Mar 25, 2025 Editor Stephen Sabia Contact Laura Betz laura.e.betz@nasa.gov Related Terms

Spectacular Northern Lights shine across the UK

Astronomy News - Wed, 26/03/2025 - 09:55

Spectacular displays of the Northern Lights have been seen over recent nights with the potential for more to come.

NASA’s Lunar Reconnaissance Orbiter Views IM-2 on Moon’s Surface

Astronomy News - Wed, 26/03/2025 - 09:55

1 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

NASA’s LRO (Lunar Reconnaissance Orbiter) imaged Intuitive Machines’ IM-2 on the Moon’s surface on March 7, just under 24 hours after the spacecraft landed.

Later that day Intuitive Machines called an early end of mission for IM-2, which carried NASA technology demonstrations as part of the agency’s CLPS (Commercial Lunar Payload Services) initiative and Artemis campaign.

The Intuitive Machines IM-2 Athena lander, indicated here with a white arrow, reached the surface of the Moon on March 6, 2025, near the center of Mons Mouton. NASA’s Lunar Reconnaissance Orbiter (LRO) imaged the site at 12:54 p.m. EST on March 7.NASA/Goddard/Arizona State University

The IM-2 mission lander is located closer to the Moon’s South Pole than any previous lunar lander.

LRO is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland, for the Science Mission Directorate at NASA Headquarters in Washington. Launched on June 18, 2009, LRO has collected a treasure trove of data with its seven powerful instruments, making an invaluable contribution to our knowledge about the Moon. NASA is returning to the Moon with commercial and international partners to expand human presence in space and bring back new knowledge and opportunities.

More on this story from Arizona State University’s LRO Camera website

Media Contact:
Nancy N. Jones
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Share Details Last Updated Mar 25, 2025 Related Terms

A PR drag origin for the Fomalhaut disk's pervasive inner dust: constraints on collisional strengths, icy composition, and embedded planets

Stars and stellar evolution - Tue, 25/03/2025 - 10:51
arXiv:2503.18127v1 Announce Type: new Abstract: Recent JWST observations of the Fomalhaut debris disk have revealed a significant abundance of dust interior to the outer planetesimal belt, raising questions about its origin and maintenance. In this study, we apply an analytical model to the Fomalhaut system, that simulates the dust distribution interior to a planetesimal belt, as collisional fragments across a range of sizes are dragged inward under Poynting-Robertson (PR) drag. We generate spectral energy distributions and synthetic JWST/MIRI images of the model disks, and perform an extensive grid search for particle parameters -- pertaining to composition and collisional strength -- that best match the observations. We find that a sound fit can be found for particle properties that involve a substantial water ice component, around 50--80% by total volume, and a catastrophic disruption threshold, $Q_D^\star$, at a particle size of $D\!\approx\!30\,$um of 2--4$\,\times\,10^6\,$erg/g. Based on the expected dynamical depletion of migrating dust by an intervening planet we discount planets with masses $>1\,M_\mathrm{Saturn}$ beyond $\sim50\,$au in the extended disk, though a planet shepherding the inner edge of the outer belt of up to $\sim2\,M_\mathrm{Saturn}$ is reconcilable with the PR-drag-maintained disk scenario, contingent upon higher collisional strengths. These results indicate that PR drag transport from the outer belt alone can account for the high interior dust contents seen in the Fomalhaut system, which may thus constitute a common phenomenon in other belt-bearing systems. This establishes a framework for interpreting mid-planetary system dust around other stars, with our results for Fomalhaut providing a valuable calibration of the models.

A PR drag origin for the Fomalhaut disk's pervasive inner dust: constraints on collisional strengths, icy composition, and embedded planets

Planetary systems - Tue, 25/03/2025 - 10:51
arXiv:2503.18127v1 Announce Type: new Abstract: Recent JWST observations of the Fomalhaut debris disk have revealed a significant abundance of dust interior to the outer planetesimal belt, raising questions about its origin and maintenance. In this study, we apply an analytical model to the Fomalhaut system, that simulates the dust distribution interior to a planetesimal belt, as collisional fragments across a range of sizes are dragged inward under Poynting-Robertson (PR) drag. We generate spectral energy distributions and synthetic JWST/MIRI images of the model disks, and perform an extensive grid search for particle parameters -- pertaining to composition and collisional strength -- that best match the observations. We find that a sound fit can be found for particle properties that involve a substantial water ice component, around 50--80% by total volume, and a catastrophic disruption threshold, $Q_D^\star$, at a particle size of $D\!\approx\!30\,$um of 2--4$\,\times\,10^6\,$erg/g. Based on the expected dynamical depletion of migrating dust by an intervening planet we discount planets with masses $>1\,M_\mathrm{Saturn}$ beyond $\sim50\,$au in the extended disk, though a planet shepherding the inner edge of the outer belt of up to $\sim2\,M_\mathrm{Saturn}$ is reconcilable with the PR-drag-maintained disk scenario, contingent upon higher collisional strengths. These results indicate that PR drag transport from the outer belt alone can account for the high interior dust contents seen in the Fomalhaut system, which may thus constitute a common phenomenon in other belt-bearing systems. This establishes a framework for interpreting mid-planetary system dust around other stars, with our results for Fomalhaut providing a valuable calibration of the models.

A PR drag origin for the Fomalhaut disk's pervasive inner dust: constraints on collisional strengths, icy composition, and embedded planets

Recent IoA Publications - Tue, 25/03/2025 - 10:51
arXiv:2503.18127v1 Announce Type: new Abstract: Recent JWST observations of the Fomalhaut debris disk have revealed a significant abundance of dust interior to the outer planetesimal belt, raising questions about its origin and maintenance. In this study, we apply an analytical model to the Fomalhaut system, that simulates the dust distribution interior to a planetesimal belt, as collisional fragments across a range of sizes are dragged inward under Poynting-Robertson (PR) drag. We generate spectral energy distributions and synthetic JWST/MIRI images of the model disks, and perform an extensive grid search for particle parameters -- pertaining to composition and collisional strength -- that best match the observations. We find that a sound fit can be found for particle properties that involve a substantial water ice component, around 50--80% by total volume, and a catastrophic disruption threshold, $Q_D^\star$, at a particle size of $D\!\approx\!30\,$um of 2--4$\,\times\,10^6\,$erg/g. Based on the expected dynamical depletion of migrating dust by an intervening planet we discount planets with masses $>1\,M_\mathrm{Saturn}$ beyond $\sim50\,$au in the extended disk, though a planet shepherding the inner edge of the outer belt of up to $\sim2\,M_\mathrm{Saturn}$ is reconcilable with the PR-drag-maintained disk scenario, contingent upon higher collisional strengths. These results indicate that PR drag transport from the outer belt alone can account for the high interior dust contents seen in the Fomalhaut system, which may thus constitute a common phenomenon in other belt-bearing systems. This establishes a framework for interpreting mid-planetary system dust around other stars, with our results for Fomalhaut providing a valuable calibration of the models.

How do Massive Primordial Black Holes Impact the Formation of the First Stars and Galaxies?

Cosmology and Fundamental physics - Tue, 25/03/2025 - 10:40
arXiv:2503.17585v1 Announce Type: new Abstract: We investigate the impact of massive primordial black holes (PBHs; $m_{\rm BH}\sim 10^6~M_{\odot}$) on the star formation and first galaxy assembly process using high-resolution hydrodynamical simulations from $z = 1100$ to $z \sim 9$. We find that PBH accretion is self-regulated by feedback, suppressing mass growth unless feedback is weak. PBHs accelerate structure formation by seeding dark matter halos and gravitationally attracting gas, but strong feedback can delay cooling and suppress star formation. In addition, the presence of baryon-dark matter streaming creates an offset between the PBH location and the peaks induced in gas density, promoting earlier and more efficient star formation compared to standard $\Lambda$CDM. By $z \sim 10$, PBH-seeded galaxies form dense star clusters, with PBH-to-stellar mass ratios comparable to observed high-$z$ AGN like UHZ-1. Our results support PBHs as viable SMBH seeds but do not exclude alternative scenarios. We emphasize that PBH-seeding provides a natural explanation for some of the newly-discovered overmassive SMBHs at high redshift, in particular those with extreme ratios of BH-to-dynamical (virial) mass that challenge standard formation channels. Future studies with ultra-deep JWST surveys, the Roman Space Telescope, and radio surveys with facilities such as SKA and HERA will be critical in distinguishing PBH-driven SMBH growth from other pathways.

How do Massive Primordial Black Holes Impact the Formation of the First Stars and Galaxies?

Galaxy Evolution and AGN - Tue, 25/03/2025 - 10:40
arXiv:2503.17585v1 Announce Type: new Abstract: We investigate the impact of massive primordial black holes (PBHs; $m_{\rm BH}\sim 10^6~M_{\odot}$) on the star formation and first galaxy assembly process using high-resolution hydrodynamical simulations from $z = 1100$ to $z \sim 9$. We find that PBH accretion is self-regulated by feedback, suppressing mass growth unless feedback is weak. PBHs accelerate structure formation by seeding dark matter halos and gravitationally attracting gas, but strong feedback can delay cooling and suppress star formation. In addition, the presence of baryon-dark matter streaming creates an offset between the PBH location and the peaks induced in gas density, promoting earlier and more efficient star formation compared to standard $\Lambda$CDM. By $z \sim 10$, PBH-seeded galaxies form dense star clusters, with PBH-to-stellar mass ratios comparable to observed high-$z$ AGN like UHZ-1. Our results support PBHs as viable SMBH seeds but do not exclude alternative scenarios. We emphasize that PBH-seeding provides a natural explanation for some of the newly-discovered overmassive SMBHs at high redshift, in particular those with extreme ratios of BH-to-dynamical (virial) mass that challenge standard formation channels. Future studies with ultra-deep JWST surveys, the Roman Space Telescope, and radio surveys with facilities such as SKA and HERA will be critical in distinguishing PBH-driven SMBH growth from other pathways.

How do Massive Primordial Black Holes Impact the Formation of the First Stars and Galaxies?

Recent IoA Publications - Tue, 25/03/2025 - 10:40
arXiv:2503.17585v1 Announce Type: new Abstract: We investigate the impact of massive primordial black holes (PBHs; $m_{\rm BH}\sim 10^6~M_{\odot}$) on the star formation and first galaxy assembly process using high-resolution hydrodynamical simulations from $z = 1100$ to $z \sim 9$. We find that PBH accretion is self-regulated by feedback, suppressing mass growth unless feedback is weak. PBHs accelerate structure formation by seeding dark matter halos and gravitationally attracting gas, but strong feedback can delay cooling and suppress star formation. In addition, the presence of baryon-dark matter streaming creates an offset between the PBH location and the peaks induced in gas density, promoting earlier and more efficient star formation compared to standard $\Lambda$CDM. By $z \sim 10$, PBH-seeded galaxies form dense star clusters, with PBH-to-stellar mass ratios comparable to observed high-$z$ AGN like UHZ-1. Our results support PBHs as viable SMBH seeds but do not exclude alternative scenarios. We emphasize that PBH-seeding provides a natural explanation for some of the newly-discovered overmassive SMBHs at high redshift, in particular those with extreme ratios of BH-to-dynamical (virial) mass that challenge standard formation channels. Future studies with ultra-deep JWST surveys, the Roman Space Telescope, and radio surveys with facilities such as SKA and HERA will be critical in distinguishing PBH-driven SMBH growth from other pathways.

Glowing spiral in UK sky believed to be caused by SpaceX launch

Astronomy News - Tue, 25/03/2025 - 08:57

The Falcon 9 is a reusable rocket. After launching into space, it releases what is called its payload - whatever it is carrying, such as a satellite, to complete its mission - which continues its journey into space.

The rocket then turns back around towards Earth. As it does, it ejects any leftover fuel, which freezes instantly due to the altitude in a spiral pattern caused by the rocket's movement.

Light is then reflected off the frozen fuel, making it visible on Earth.

The glowing swirl was photographed in England and Wales, and was also seen in parts of Europe.

Astronomer Allan Trow said it had appeared above Wales's Bannau Brycheiniog national park at around 20:00.

He said he had seen the phenomenon before around four years ago.

"But these are pretty rare," he told the BBC, and agreed the rocket was its likely source.

Stockport-based Sonia was already out with her telescope when she saw "a swirling galaxy that was moving across the sky".

People living almost 200 miles (321km) away also spotted the unusual glow.

Steven Hall was taking his bins out from his home in rural Suffolk when he saw what looked like "a huge Catherine wheel which appeared to have its own atmosphere around it".

He added: "It did pass my mind, is this an unexplained, unidentified flying object?"

SpaceX said on X the launch was carried out on behalf of the US government National Reconnaissance Office mission. The Kennedy Space Center also said on X the launch was a classified mission for that office.

On the road to the radius valley: distinguishing between gas dwarfs and water worlds with young transiting exoplanets

Recent IoA Publications - Mon, 24/03/2025 - 16:19
arXiv:2503.17364v1 Announce Type: new Abstract: The detection of young transiting exoplanets represents a new frontier in our understanding of planet formation and evolution. For the population of observed close-in sub-Neptunes, two proposed formation pathways can reproduce their observed masses and radii at $\sim$Gyr ages: the "gas dwarf" hypothesis and the "water world" hypothesis. We show that a sub-Neptune's size at early ages $\lesssim 100$ Myrs is strongly dependent on the bulk mean molecular weight within its envelope. As a result, gas dwarfs and water worlds should diverge in size at early ages since the mean molecular weight of gas dwarf envelopes is predicted to be smaller than that of water worlds. We construct population models under both scenarios that reproduce Kepler demographics in the age range $\sim1-10$ Gyrs. We find tentative evidence that the gas dwarf model is more consistent with the small population of young exoplanets $< 40$ Myrs from TESS. We show that planet radius is relatively insensitive to planet mass for young, puffy sub-Neptunes, meaning that well-characterised masses are not necessarily required to exploit the effects of mean molecular weight at the population level. We confirm the predicted difference in planet size between the models is also true under mixed-envelope scenarios, in which envelopes consist of mixtures of hydrogen and steam. We highlight that transit surveys of young exoplanets should target the youngest observable stellar clusters to exploit the effects of mean molecular weight.

On the road to the radius valley: distinguishing between gas dwarfs and water worlds with young transiting exoplanets

Planetary systems - Mon, 24/03/2025 - 16:19
arXiv:2503.17364v1 Announce Type: new Abstract: The detection of young transiting exoplanets represents a new frontier in our understanding of planet formation and evolution. For the population of observed close-in sub-Neptunes, two proposed formation pathways can reproduce their observed masses and radii at $\sim$Gyr ages: the "gas dwarf" hypothesis and the "water world" hypothesis. We show that a sub-Neptune's size at early ages $\lesssim 100$ Myrs is strongly dependent on the bulk mean molecular weight within its envelope. As a result, gas dwarfs and water worlds should diverge in size at early ages since the mean molecular weight of gas dwarf envelopes is predicted to be smaller than that of water worlds. We construct population models under both scenarios that reproduce Kepler demographics in the age range $\sim1-10$ Gyrs. We find tentative evidence that the gas dwarf model is more consistent with the small population of young exoplanets $< 40$ Myrs from TESS. We show that planet radius is relatively insensitive to planet mass for young, puffy sub-Neptunes, meaning that well-characterised masses are not necessarily required to exploit the effects of mean molecular weight at the population level. We confirm the predicted difference in planet size between the models is also true under mixed-envelope scenarios, in which envelopes consist of mixtures of hydrogen and steam. We highlight that transit surveys of young exoplanets should target the youngest observable stellar clusters to exploit the effects of mean molecular weight.

NASA’s Webb Telescope Unmasks True Nature of the Cosmic Tornado

Astronomy News - Mon, 24/03/2025 - 16:04
Explore This Section 6 Min Read NASA’s Webb Telescope Unmasks True Nature of the Cosmic Tornado NASA’s James Webb Space Telescope observed Herbig-Haro 49/50, an outflow from a nearby still-forming star, in high-resolution near- and mid-infrared light. Credits: NASA, ESA, CSA, STScI

Craving an ice cream sundae with a cherry on top? This random alignment of Herbig-Haro 49/50 — a frothy-looking outflow from a nearby protostar — with a multi-hued spiral galaxy may do the trick. This new composite image combining observations from NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) provides a high-resolution view to explore the exquisite details of this bubbling activity.

Herbig-Haro objects are outflows produced by jets launched from a nearby, forming star. The outflows, which can extend for light-years, plow into a denser region of material. This creates shock waves, heating the material to higher temperatures. The material then cools by emitting light at visible and infrared wavelengths.

Image A:
Herbig-Haro 49/50 (NIRCam and MIRI Image) NASA’s James Webb Space Telescope observed Herbig-Haro 49/50, an outflow from a nearby still-forming star, in high-resolution near- and mid-infrared light. The intricate features of the outflow, represented in reddish-orange color, provide detailed clues about how young stars form and how their jet activity affects the environment around them. Like the wake of a speeding boat, the bow shocks in this image have an arc-like appearance as the fast-moving jet from the young star slams into the surrounding dust and gas. A chance alignment in this direction of the sky provides a beautiful juxtaposition of this nearby Herbig-Haro object with a more distant spiral galaxy in the background. Herbig-Haro 49/50 gives researchers insights into the early phases of the formation of low-mass stars similar to our own Sun. In this Webb image, blue represents light at 2.0-microns (F200W), cyan represents light at 3.3-microns (F335M), green is 4.4-microns (F444W), orange is 4.7-microns (F470N), and red is 7.7-microns (F770W).NASA, ESA, CSA, STScI

When NASA’s retired Spitzer Space Telescope observed it in 2006, scientists nicknamed Herbig-Haro 49/50 (HH 49/50) the “Cosmic Tornado” for its helical appearance, but they were uncertain about the nature of the fuzzy object at the tip of the “tornado.”  With its higher imaging resolution, Webb provides a different visual impression of HH 49/50 by revealing fine features of the shocked regions in the outflow, uncovering the fuzzy object to be a distant spiral galaxy, and displaying a sea of distant background galaxies.

Image B:
Herbig-Haro 49/50 (Spitzer and Webb Images Side-by-Side) This side-by-side comparison shows a Spitzer Space Telescope Infrared Array Camera image of HH 49/50 (left) versus a Webb image of the same object (right) using the NIRCam (Near-infrared Camera) instrument and MIRI (Mid-infrared Instrument). The Webb image shows intricate details of the heated gas and dust as the protostellar jet slams into the material. Webb also resolves the “fuzzy” object located at the tip of the outflow into a distant spiral galaxy. The Spitzer image shows 3.6-micron light in blue, the 4.5-micron in green, and the 8.0-micron in red (IRAC1, IRAC2, IRAC4). In the Webb image, blue represents light at 2.0-microns (F200W), cyan represents light at 3.3-microns (F335M), green is 4.4-microns (F444W), orange is 4.7-microns (F470N), and red is 7.7-microns (F770W).NASA, ESA, CSA, STScI, NASA-JPL, SSC

HH 49/50 is located in the Chamaeleon I Cloud complex , one of the nearest active star formation regions in our Milky Way, which is creating numerous low-mass stars similar to our Sun. This cloud complex is likely similar to the environment that our Sun formed in. Past observations of this region show that the HH 49/50 outflow is moving away from us at speeds of 60-190 miles per second (100-300 kilometers per second) and is just one feature of a larger outflow.

Webb’s NIRCam and MIRI observations of HH 49/50 trace the location of glowing hydrogen molecules, carbon monoxide molecules, and energized grains of dust, represented in orange and red, as the protostellar jet slams into the region. Webb’s observations probe details on small spatial scales that will help astronomers to model the properties of the jet and understand how it is affecting the surrounding material.

The arc-shaped features in HH 49/50, similar to a water wake created by a speeding boat, point back to the source of this outflow. Based on past observations, scientists suspect that a protostar known as Cederblad 110 IRS4 is a plausible driver of the jet activity. Located roughly 1.5 light-years away from HH 49/50 (off the lower right corner of the Webb image), CED 110 IRS4 is a Class I protostar. Class I protostars are young objects (tens of thousands to a million years old) in the prime time of gaining mass. They usually have a discernable disk of material surrounding them that is still falling onto the protostar. Scientists recently used Webb’s NIRCam and MIRI observations to study this protostar and obtain an inventory  of the icy composition of its environment.

These detailed Webb images of the arcs in HH 49/50 can more precisely pinpoint the direction to the jet source, but not every arc points back in the same direction. For example, there is an unusual outcrop feature (at the top right of the main outflow) which could be another chance superposition of a different outflow, related to the slow precession of the intermittent jet source. Alternatively, this feature could be a result of the main outflow breaking apart.

Video Caption:
This visualization examines the three-dimensional structure of Herbig-Haro 49/50 (HH 49/50) as seen in near- and mid-infrared light by the James Webb Space Telescope. HH 49/50 is an outflow produced by the jet of a nearby still-forming star in the Chamaeleon I Cloud complex, one of the nearest active star formation regions in our Milky Way. At a distance of 625 light-years from Earth, this new composite infrared image (using data from program 6558, PI: M. Garcia Marin) allows researchers to examine its details on small spatial scales like never before.
 
Visualization Credit: NASA, ESA, CSA, J. DePasquale (STScI), L. Hustak (STScI), G. Bacon (STScI), R. Crawford (STScI), D. Kirshenblat (STScI), C. Nieves (STScI), A. Pagan (STScI), F. Summers (STScI).

The galaxy that appears by happenstance at the tip of HH 49/50 is a much more distant, face-on spiral galaxy. It has a prominent central bulge represented in blue that shows the location of older stars. The bulge also shows hints of “side lobes” suggesting that this could be a barred-spiral galaxy. Reddish clumps within the spiral arms show the locations of warm dust and groups of forming stars. The galaxy even displays evacuated bubbles in these dusty regions, similar to nearby galaxies observed by Webb as part of the PHANGS program.

Webb has captured these two unassociated objects in a lucky alignment. Over thousands of years, the edge of HH 49/50 will move outwards and eventually appear to cover up the distant galaxy.

Want more? Take a closer look at the image, “fly through” it in a visualization, and compare Webb’s image to the Spitzer Space Telescope’s.

Herbig-Haro 49/50 is located about 625 light-years from Earth in the constellation Chamaeleon.

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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Media Contacts

Laura Betz – laura.e.betz@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.

Quyen Hartqhart@stsci.edu
Space Telescope Science Institute, Baltimore, Md.

Christine Pulliamcpulliam@stsci.edu
Space Telescope Science Institute, Baltimore, Md.

Related Information

Images – Webb images of other protostar outflows –  L483HH 46/47, and HH 211

Animation Video – “Exploring Star and Planet Formation” 

Interactive – Explore the jets emitted by young stars in multiple wavelengths: ViewSpace Interactive

Article – Read more about Herbig-Haro objects

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Thu 15 May 11:00: LCLU Coffee - Ligia F Coelho on &quot;the changing colours of our planet as a tool for ilfe detection on icy moons and exoplanets&quot;

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We cannot predict life. We can, instead, learn from Earth’s biodiversity and their varied molecular catalogue of markers of adaptability. Biopigments are widespread biomolecules that serve as powerful surface biomarkers of adaptability to extreme conditions on our planet. These molecules have distinct and unique spectral signatures providing a promising avenue for detecting extraterrestrial life. However, current surface models for other planets overlook Earth’s broader biodiversity. In the Solar System, current models struggle to constrain non-icy mysterious spots on the surface of the Jovian icy moon Europa for lack of matching reference spectra. In parallel, exoplanet surface models tend to overemphasize chlorophyll-based landscapes, often constrained by the assumption that photosynthesis requires visible light. This introduces unnecessary restrictions on atmospheric opacity and composition. In reality, Earth’s biosphere hosts a vast array of biopigments capable of harnessing energy across the UV to IR spectrum, driving diverse metabolisms, volatile byproducts, and environmental adaptations—many of which serve as analogues for targets to be studied with future telescopes and space missions. By integrating Earth’s biological and evolutionary diversity with astrophysical tools, I will present life-detection frameworks based on a broad spectral dataset. I will show how in situ reflectance data from Svalbard (Arctic) and Atacama Desert can help us correlate biosignatures with specific environments. These findings contribute to biologically informed planetary models, crucial for the next generation missions, including Extremely Large Telescopes (ELTs), the Habitable Worlds Observatory (HWO) and Large Interferometer For Exoplanets (LIFE), as well as NASA ’s Europa Clipper, ESA ’s Juice and Enceladus L4. These exciting new instruments will probe several planetary surfaces for a new biosphere where orange, yellow, or purple may be the new green.

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