Laser trial run kickstarts new era of interferometry

PR Image eso2519a
Four lasers for the VLTI

PR Image eso2519b
Artificial stars created by lasers as the VLTI pointed at the Tarantula Nebula

PR Image eso2519c
Closer view of the four lasers for the VLTI

PR Image eso2519d
View of the four lasers from the ALPACA camera

PR Image eso2519e
Binary star imaged by GRAVITY+

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Videos


PR Video eso2519a
Laser trial run kickstarts new era of interferometry | Chasing Starlight


PR Video eso2519b
Timelapse of the VLTI lasers (colour)


PR Video eso2519c
Animation of the light path through the VLTI's GRAVITY+ instrument


PR Video eso2519d
Timelapse of VLTI lasers

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Last week, four lasers were projected into the skies above the European Southern Observatory’s (ESO’s) Paranal site in Chile. The lasers are each used to create an artificial star, which astronomers use to measure and then correct the blur caused by Earth's atmosphere. The striking launch of these lasers, one from each of the eight-metre telescopes at Paranal, is a significant milestone of the GRAVITY+ project — a large and complex upgrade to ESO’s Very Large Telescope Interferometer (VLTI). GRAVITY+ unlocks a greater observing power and a much wider sky coverage for the VLTI than previously possible.

“This is a very important milestone for a facility that is completely unique in the world,” says Antoine Mérand, an ESO astronomer and VLTI Programme Scientist.

The VLTI combines light from several individual telescopes of the VLT (either the four eight-metre Unit Telescopes (UTs) or the four smaller Auxiliary Telescopes) using interferometry. GRAVITY+ is an upgrade to the VLTI, with a focus on GRAVITY, a very successful VLTI instrument that has been used to image exoplanets;observe stars near and far and perform detailed observations of faint objects;orbiting the Milky Way’s supermassive black hole. GRAVITY+ also encompasses infrastructural changes to the telescopes and upgrades to the VLTI underground tunnels, where the light beams are brought together. The installation of a laser at each of the previously unequipped UTs is a key achievement of this long-term project, transforming the VLTI into the most powerful optical interferometer in the world.

“The VLTI with GRAVITY has already enabled so many unpredicted discoveries, we are excited to see how GRAVITY+ will push the boundaries even further,” says GRAVITY+ Principal Investigator Frank Eisenhauer of the Max-Planck Institute for Extraterrestrial Physics (MPE), Germany, which led the consortium carrying out the upgrade. [1]

The series of upgrades has been ongoing for a few years and includes revised adaptive-optics technology — a system to correct the blur caused by the Earth’s atmosphere — with advanced state-of-the-art sensors and deformable mirrors. Until now, for the VLTI, adaptive-optics corrections have been done by pointing to bright reference stars that need to be close to the target, limiting the number of objects we can observe. With the installation of a laser at each of the UTs, a bright artificial star is created 90 km above Earth’s surface, enabling the correction of atmospheric blur anywhere on the sky. This unlocks the whole southern sky to the VLTI and enhances its observing power dramatically.

“This opens up the instrument to observations of objects in the early distant Universe, such as the quasar we observed on the second night where we resolved the hot, oxygen emitting gas very close to the black hole,” says Taro Shimizu, an MPE astronomer who is a member of the instrument consortium. With lasers on the telescopes used by the VLTI, astronomers will be able to study distant active galaxies and directly measure the mass of the supermassive black holes that power them, as well as observe young stars and the planet-forming discs around them.

The VLTI’s improved capabilities will drastically increase the amount of light that can travel through the system, making the facility up to 10 times more sensitive. “A big goal of GRAVITY+ is to allow for deep observations of faint targets,” explains Julien Woillez, an ESO astronomer and GRAVITY+ project scientist. This increased ability to detect dimmer objects will allow observations of isolated stellar black holes, free-floating planets that do not orbit a parent star and stars closest to the Milky Way’s supermassive black hole Sgr A*.

A first target for the GRAVITY+ and ESO teams at Paranal performing test observations using the new lasers was a cluster of massive stars at the centre of the Tarantula Nebula, a star-forming region in our neighbouring galaxy the Large Magellanic Cloud. These first observations revealed that a bright object in the nebula, thought to be an extremely massive single star, is actually a binary of two stars close together. This showcases the stunning capabilities and scientific potential of the upgraded VLTI.

This improvement is beyond just an update and was first envisioned decades ago. The laser system was suggested in the final report of the “Very Large Telescope Project” in 1986 before the VLTI even existed: “If it could work in practice, it would be a breakthrough,” the report stated. Now this breakthrough is a reality.

Source: ESO/News

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Notes

[1] The GRAVITY+ consortium consists of the following partners:

• Max Planck Institute for Extraterrestrial Physics (MPE); Max Planck Institute for Astronomy; University of Cologne (Germany)
• Institut National des Sciences de l'Univers, French National Centre for Scientific Research; Institut de Planétologie et d'Astrophysique de Grenoble; Laboratoire d’instrumentation et de recherche en astrophysique (LIRA); Lagrange Laboratory; Centre de Recherche Astrophysique de Lyon (France)
• Instituto Superior Técnico’s Centre for Astrophysics and Gravitation (CENTRA); University of Lisbon; University of Porto (Portugal)
• University of Southampton (UK)
• Katholieke Universiteit Leuven (Belgium)
• University College Dublin (Ireland)
• Instituto de Astronomia – Universidad Nacional Autónoma de México (Mexico)
• European Southern Observatory.

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More information

The GRAVITY+ Co-Investigators are: Frank Eisenhauer (PI; MPE, Germany), Paulo Garcia (Faculdade de Engenharia, Universidade do Porto and CENTRA research unit, Portugal), Sebastian Hönig (University of Southampton, UK), Laura Kreidberg (Max Planck Institute for Astronomy, Germany), Jean-Baptiste Le Bouquin (Institut de Planétologie et d'Astrophysique de Grenoble, Université Grenoble Alpes, France), Thibaut Paumard (LIRA, Observatoire de Paris, France), Christian Straubmeier (University of Cologne, Germany).

At ESO, the GRAVITY+ upgrade is led by Frederic Gonte (Project Manager), Julien Woillez (Project Scientist), Sylvain Oberti (Project Engineer), and Luis Esteras Otal (VLTI Systems Engineer).

ESO’s Paranal Observatory in Chile is currently under threat by the planned INNA project, set to be located just 11 kilometres from the VLTI. An especially worrying impact from INNA is due to microvibrations since they make combining light in the VLTI tunnels much more challenging. In fact, a detailed technical analysis performed earlier this year revealed that INNA’s wind turbines could produce an increase in ground vibrations large enough to impair VLTI operations. Relocating planned projects such as INNA from the areas surrounding Paranal is key to allowing world-class astronomical facilities to operate at their maximum potential, as well as to protecting a truly special place with pristine dark skies and other conditions that make it an astronomy world-leader.
The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration for astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, Czechia, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as survey telescopes such as VISTA. Also at Paranal, ESO will host and operate the south array of the Cherenkov Telescope Array Observatory, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates ALMA on Chajnantor, a facility that observes the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.

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Links

• Photos of the VLT/I
• ESO's blog post on GRAVITY+
• ESO's GRAVITY+ page
• MPE's GRAVITY+ page
• For journalists: subscribe to receive our releases under embargo in your language
• For scientists: got a story? Pitch your research
• New ESO analysis confirms severe damage from industrial complex planned near Paranal

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Contacts:

Frank Eisenhauer
Max Planck Institute for Extraterrestrial Physics
Garching bei München, Germany
Tel: +49 89 30000 3100
Email: eisenhau@mpe.mpg.de

Taro Shimizu
Max Planck Institute for Extraterrestrial Physics
Garching bei München, Germany
Tel: +49 89 30000 3392
Email: shimizu@mpe.mpg.de

Jean-Baptiste Le Bouquin
Institut National des Sciences de l’Univers, CNRS
Grenoble, France
Tel: +33 4 76 14 36 82
Email: jean-baptiste.lebouquin@univ-grenoble-alpes.fr

Antoine Mérand
European Southern Observatory
Garching bei München, Germany
Tel: +49 89 3200 6630
Email: amerand@eso.org

Julien Woillez
European Southern Observatory
Garching bei München, Germany
Tel: +49 89 3200 6273
Email: jwoillez@eso.org

Bárbara Ferreira
ESO Media Manager
Garching bei München, Germany
Tel: +49 89 3200 6670
Cell: +49 151 241 664 00
Email: press@eso.org

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A disruptive neighbour

NGC 1511

A spiral galaxy, tilted away so that it is seen mostly from the edge. The disc of the galaxy glows blue from its centre, due to younger stars in the spiral arms. There are large and small patches of gas, glowing in red and pink colours, where new stars are forming. Webs of dark dust are spread over the disc. The glow of the disc fades into a dark background, with a couple of stars. Credit: ESA/Hubble & NASA, D. Thilker

Though interesting to look at, NGC 1511 is one galaxy you might not want for a neighbour. Seen in this ESA/Hubble Picture of the Week, NGC 1511 is a peculiar spiral galaxy located roughly 50 million light-years away in the constellation Hydrus.

Like many galaxies, NGC 1511 doesn’t travel through space alone. Instead, it does so with a pair of small galactic companions called NGC 1511A and NGC 1511B, both of which lie outside the frame of this Hubble image. NGC 1511B is situated closest to NGC 1511, and the two galaxies have apparently clashed in the past; a narrow strand of hydrogen gas connects them, and NGC 1511B has been stretched and distorted by the encounter. Researchers have even found evidence that NGC 1511 once had another small companion galaxy that it has disrupted entirely!

These disruptions have an impact on NGC 1511, too. The galaxy is experiencing a burst of star formation, and its disc features strange loops and plumes that could point to past interactions with its neighbouring galaxies. Researchers will use Hubble’s keen observations of NGC 1511 to study star clusters embedded within its dusty gas, seeking to understand how matter is cycled from interstellar clouds to stars and back to clouds once again.

Source: ESA/Hubble/potw

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Black Hole Flare is Biggest and Most Distant Seen

This artist's concept depicts a supermassive black hole in the process of shredding a massive star—at least 30 times the mass of our Sun—to pieces. Scientists propose this is what happened around the distant black hole referred to as J2245+3743, which in 2018, brightened dramatically to create the brightest black hole flare ever recorded, shining with the light of 10 trillion suns. This is likely the most massive star-shredding event (formally called a tidal disruption event or TDE) ever observed and one of only a few to have occurred in an active galactic nucleus (AGN), which is an active supermassive black hole "feeding" off material in a surrounding disk. The stunning flare was discovered by the Zwicky Transient Facility (ZTF), based at Caltech's Palomar Observatory, and the Caltech-led Catalina Real-Time Transient Survey. Credit: Caltech/R. Hurt (IPAC)

The 48-inch Samuel Oschin Telescope at Palomar Observatory, where ZTF resides.
Credit: Palomar/Caltech

Matthew Graham
Credit: Nick Macdonald

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The flare, co-discovered by the Zwicky Transient Facility, may be the result of a mega black-hole meal

The most massive stars in the universe are destined to explode as brilliant supernova before collapsing into black holes. Yet one huge star appears to have never fulfilled its destiny; in a twist of irony, the star wandered too close to a gargantuan black hole, which gobbled it up, shredding the star to bits and pieces.

That is the most likely explanation to come from authors of a new Nature Astronomy report describing the most powerful and most distant flare of energy ever recorded from a supermassive black hole. The cosmic object was first observed in 2018 by the US National Science Foundation (NSF)-funded Zwicky Transient Facility (ZTF), based at Caltech's Palomar Observatory, and the Caltech-led Catalina Real-Time Transient Survey, which is also funded by NSF. The flare rapidly brightened by a factor of 40 over a period of months, and, at its peak, was 30 times more luminous than any previous black hole flare seen to date. At its brightest, the flare shined with the light of 10 trillion suns.

The supermassive black hole behind the flare is a type of accreting, or feeding, black hole called an active galactic nucleus (AGN). Referred to as J2245+3743, this AGN is estimated to be 500 million times more massive than our Sun. It resides 10 billion light-years away in the remote universe. Because light has a finite speed and takes time to reach us, astronomers observe distant events like this one in the past, when the universe was young.

"The energetics show this object is very far away and very bright," says study lead author Matthew Graham, research professor of astronomy at Caltech, as well as the project scientist for ZTF, and a co-principal investigator of the project. "This is unlike any AGN we've ever seen."

Astronomers are continuing to monitor the black hole flare though it is fading over time. In fact, in addition to witnessing the object in the past, time itself runs slower at the remote site of the black hole compared to our own experience of time. "It's a phenomenon called cosmological time dilation due to stretching of space and time. As the light travels across expanding space to reach us, its wavelength stretches as does time itself," Graham explains, noting that long-lived surveys like ZTF and Catalina are important to fully witness events in the past because, in this case, "seven years here is two years there. We are watching the event play back at quarter speed."

To determine what could cause such a dramatic burst of light in the cosmos, the researchers thoroughly examined a list of possibilities, concluding that the most likely culprit is a tidal disruption event (TDE). This phenomenon occurs when a supermassive black hole's gravity shears a star that comes too close, slowly consuming the star over time as it spirals into the black hole. The fact that the black hole flare J2245+3743 is still going indicates that we are witnessing a star not yet fully devoured but rather like "a fish only halfway down the whale's gullet," Graham says.

If the flare is from a TDE, the scientists estimate that the supermassive black hole gobbled a star with a mass at least 30 times greater than that of our Sun. The previous record holder for the largest candidate TDE, an event nicknamed Scary Barbie after its initial ZTF classification as ZTF20abrbeie, was not nearly as intense. That TDE, which is also thought to have originated from an AGN, was 30 times weaker than that of J2245+3743, and its doomed star is estimated to have been between three and 10 solar masses.

Stellar Snack Within a Black Hole's Disk

Most of the roughly 100 TDEs seen to date do not take place around AGN—massive structures that consist of supermassive black holes surrounded by large, swirling disks of material that feed the central black hole. The AGN burble along, flaring up with their own feeding activity, which can mask TDE bursts and makes them harder to find. The recent jumbo flare J2245+3743, on the other hand, was so large that it was easier to see.

However, at first, J2245+3743 did not seem to be anything special. In 2018, after the object was first spotted, the researchers used the 200-inch Hale Telescope at Caltech's Palomar Observatory to obtain a spectrum of the object's light, but it did not reveal anything unusual. In 2023, the team noticed the flare was decaying slower than expected, so they obtained another spectrum from the W. M. Keck Observatory in Hawai‘i, which indicated the extreme brightness of this particular AGN.

"At first, it was important to establish that this extreme object was truly this bright," explains co-author K. E. Saavik Ford, a professor at the City University of New York (CUNY) Graduate Center and Borough of Manhattan Community College and American Museum of Natural History (AMNH). It was possible, she says, that the object could have been beaming the light toward us rather than glowing in all directions, but data from NASA's former Wide-field Infrared Survey Explorer (WISE) mission helped rule that out. In the end, after other scenarios were also ruled out, the researchers concluded that J2245+3743 was indeed the brightest black hole flare ever recorded.

"If you convert our entire Sun to energy, using Albert Einstein's famous formula E = mc2, that's how much energy has been pouring out from this flare since we began observing it," Ford says.

Once the team established the unprecedented brightness of the event, they looked at what could possibly have caused it. "Supernovae are not bright enough to account for this," Ford says, referring to one possibility. Instead, the team's favored explanation is a supermassive black hole slowly ripping a huge star to death.

"Stars this massive are rare," Ford says, "but we think stars within the disk of an AGN can grow larger. The matter from the disk is dumped onto stars, causing them to grow in mass."

Finding a black hole meal with such mega proportions indicates that other events like this are likely taking place across the cosmos. The researchers hope to mine through more ZTF data to find others, and the NSF and Department of Energy's Vera C. Rubin Observatory may likewise find unusually large TDEs.

"We never would have found this rare event in the first place if it weren't for ZTF," Graham says. "We've been observing the sky with ZTF for seven years now, so when we see anything flare or change, we can see what it has done in the past and how it will evolve."

The Nature Astronomy study titled "An Extremely Luminous Flare Recorded from a Supermassive Black Hole" was funded by the NSF, the Simons Foundation, NASA, and the German Research Foundation. Other Caltech authors include Andrew Drake, Yuanze Ding (MS '25), Mansi Kasliwal (PhD '11), Sam Rose, Jean Somalwar (now a postdoc at UC Berkeley), George Djorgovski, Shri Kulkarni, and Ashish Mahabal; Tracy Chen and Steven Groom of Caltech's IPAC astronomy center; and Daniel Stern of NASA's Jet Propulsion Laboratory (which is managed by Caltech). Additional authors are Barry McKernan of CUNY Graduate Center and Borough of Manhattan Community Collegeand AMNH; Matteo Cantiello of the Simons Foundation's Flatiron Institute and Princeton University; Mike Koss of Eureka Scientific; Raffaella Margutti of UC Berkeley; Phil Wiseman of University of Southampton, UK; Patrik Veres of Ruhr University in Bochum, Germany; and Eric Bellm of the University of Washington.

Caltech's ZTF is funded by the NSF and an international collaboration of partners. Additional support comes from the Heising-Simons Foundation and from Caltech. ZTF data are processed and archived by Caltech's IPAC. NASA supports ZTF's search for near-Earth objects through the Near-Earth Object Observations program.

Written by Whitney Clavin

Source: Caltech/News

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Contact:

Whitney Clavin
(626) 395‑1944
wclavin@caltech.edu

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Astronomers reveal tasty insights into exoplanet formation using SPAM

The NIRC2 image of dust around a young star named HD34282 (left) produced using an algorithm to construct images from aperture masking interferometry data. The light from the star is removed and its location is marked with a star symbol in all panels. The model that reproduces the data (middle) includes a circular inner structure around the star, which may be an envelope of dust. There is also a large protoplanetary disk around both the star and the inner structure. Between the inner structure and the protoplanetary disk is a ~40 AU gap, where planets may be forming. On the right is the image of the model after it is passed through the algorithm used on the left. This is done to test if the model can visually reproduce the data. Credit: Christina Vides / University of California Irvine / W. M. Keck Observatory.

The name SPAM is a registered trademark of Hormel Foods, LLC. This release and image are not sponsored or endorsed by Hormel Foods. Credit: W. M. Keck Observatory / Ilihia Gionson.

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Study serves up the closest-ever view of a planet-forming disk around young star HD 34282

Maunakea, Hawaiʻi – Astronomers using W. M. Keck Observatory on Maunakea, Hawaiʻi Island have taken the closest-ever look at the dusty regions where planets form, offering new insight into the earliest stages of planetary birth.

HD 34282 is one of thirty objects observed thus far as part of The Search for Protoplanets with Aperture Masking, affectionately referred to as SPAM.

“We all want to know where we came from and how our solar system formed,” said Christina Vides, a graduate student at the University of California Irvine and lead author of the study published in The Astrophysical Journal. “By studying systems like this, we can watch planet formation in action and learn what conditions give rise to worlds like our own.”

Peering Into Planet Nurseries

The team used Keck Observatory’s Near-Infrared Camera (NIRC2) which enables astronomers to see closer to a star than traditional imaging methods permit.

Their target, HD 34282, is a young star about 400 light-years away, surrounded by a thick ring of dust and gas—a “transition disk” thought to be sculpted by growing planets.

With Keck Observatory’s advanced instrumentation and adaptive optics, Vides and the team captured the most detailed view yet of the inner regions of HD 34282’s disk, revealing clumpy structures and brightness patterns that hint at possible planet-forming activity.

Although no confirmed protoplanet was detected, the observations provided the closest constraints yet on where a young planet could be hiding, as well as estimates of the star’s mass and accretion rate—key clues for modeling how its surrounding material might evolve into planets.

The Rarest of Discoveries

Early detection of protoplanets is exceptionally rare and technically challenging.

PDS 70 b and PDS 70 c are the only two confirmed protoplanets that have ever been imaged directly. Both were discovered in 2020 by Caltech observers also using Keck Observatory’s NIRC2 instrument.

Each new observation builds on that legacy, bringing astronomers closer to understanding how planetary systems emerge from swirling disks of gas and dust.

“This work is pushing the boundaries of what we can see,” said Vides. “Keck’s adaptive optics and masking capabilities make it possible to resolve features just a few astronomical units from the star—regions that are otherwise completely invisible.”

What’s Next

The team will continue using Keck’s advanced instruments to study other young stars with promising disks and compile more data for SPAM. The team is also preparing for observations using future instrumentation like SCALES, a next-generation high-contrast imager now being developed for Keck Observatory, which will expand the search for protoplanets in unprecedented detail.

“Every new system we study helps us understand a little more about how planets form and evolve,” said Vides. “It’s incredible that we can point a telescope at a young star hundreds of light-years away and actually see the conditions that could give rise to new worlds.”

Download Youtube video here

Source: W.M. Keck Observatory/Science News
Science Paper

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Euclid Sheds Light on How Galaxies Form and Transform

The “Morphological Tuning Fork” of galaxy classifications, re-created using Euclid’s high-resolution images from data release Q1. © ESA/Euclid/Euclid Consortium/NASA, diagram by J.-C. Cuillandre, L. Quilley, F. Marleau

ESA’s space telescope captures the astonishing diversity of galaxies – and MPE scientists trace how mergers shape their cores

ESA’s Euclid space telescope is revealing the patterns of galaxy evolution, capturing the shapes, sizes, and structures of millions of galaxies across cosmic time. Scientists from the Max Planck Institute for Extraterrestrial Physics (MPE) are using these data to trace how galaxies grow, merge, and transform, including identifying hundreds of systems with secondary nuclei that hint at the formation channels of supermassive black hole binaries. Euclid also uncovers rare systems with highly ionized emission lines and thousands of previously hidden dwarf galaxies, providing key insights into the building blocks of larger systems like the Milky Way. Together, these observations offer a comprehensive view of how galaxies and their central black holes coevolve across the universe.

Summary:

Euclid Telescope: ESA's Euclid space telescope captures diverse galaxy forms and structures, enhancing understanding of galaxy evolution and mergers.

Galaxy Evolution: Researchers from the Max Planck Institute for Extraterrestrial Physics (MPE) study how galaxies grow and merge, identifying systems with secondary nuclei that may host supermassive black hole binaries.

Data Insights: The first data release includes millions of galaxies, allowing astronomers to investigate connections between galaxy morphology and environmental influences.

Research Breakthroughs: Euclid’s sharp, wide-field images enable the systematic study of the central structures of galaxies and the identification of rare phenomena—including highly ionized emission lines and previously hidden dwarf galaxies—providing crucial insights into galaxy formation.

Comprehensive View: The findings illustrate the relationship between galaxy structure, star formation history, and cosmic environment, offering a holistic view of galactic evolution.

After just one year of observations, ESA’s space telescope Euclid is shedding new light on one of astronomy’s oldest questions: why does the universe contain such a stunning variety of galaxies? Just like flowers, galaxies come in a large variety of different colours, sizes, and shapes — all encapsulated in the term: morphology.

Are these different morphologies linked? How is the evolution of blue spiral galaxies related to that of giant elliptical galaxies? And how much does a galaxy’s environment — whether it lives in crowded clusters or cosmic solitude — influence its shape and fate? With millions of galaxies now catalogued in Euclid’s first data release (Q1, March 2025, ESA), astronomers are gaining access to a new treasure trove of data to address these questions.

Euclid’s sharp, wide-field view marks a breakthrough in extragalactic astronomy. Its images combine exceptional depth and resolution, allowing scientists to study more than 1.2 million large galaxies in its first year alone—and tens of millions over its six-year mission.

We understand today that the diversity of galaxies — from majestic grand-design spirals like our own Milky Way to giant ellipticals such as the mighty Messier 87 — is a consequence of their evolutionary paths. Galaxies begin their lives on the right side of the Hubble diagram (see Figure above) as disky, blue, star-forming systems. They move to the left in the diagram as they grow, gradually exhaust their gas supplies, and merge with other systems, eventually forming large elliptical galaxies.

One of the discovered systems with secondary nuclei. These are potential hosts of a second supermassive black hole that is in the process of sinking—assisted by dynamical friction—into the centre of the recently merged host galaxy. The image, in addition to the secondary nucleus, still clearly shows residual traces of the merger process. © ESA/Euclid/Euclid Consortium/MPE

A comprehensive view of cosmic evolution

Euclid’s Q1 release covers 63 square degrees of the extragalactic sky — only about 0.5% of the total dataset the mission will ultimately deliver. Yet, even this small fraction already enables a remarkable range of high-impact studies across all areas of extragalactic astronomy, demonstrating one of Euclid’s key strengths: its ability to efficiently survey vast regions of the sky and reveal rare astronomical phenomena.

Another example is the study by Daniela Vergani et al., co-led by Christoph Saulder (MPE), which identifies a rare population of 65 galaxies exhibiting highly ionised emission lines — signatures of extreme astrophysical phenomena such as active galactic nuclei, shock fronts, or Wolf–Rayet stars — offering a new window into the energetic feedback mechanisms shaping galaxy evolution.

With its remarkable sensitivity, Euclid also reveals that the most common galaxies in the Universe are not the majestic spirals but tiny dwarf galaxies—faint, low–surface-brightness systems that were once too elusive to study in detail. Among the 2,674 dwarf galaxies identified so far, about 58% are dwarf ellipticals and 42% are dwarf irregulars, some containing compact blue cores or globular clusters. These dwarfs are thought to be the building blocks of larger systems like our own Milky Way, offering vital clues to cosmic assembly on the smallest scales.

These studies — from tiny dwarfs to giant ellipticals — demonstrate Euclid’s extraordinary ability to provide a complete, multi-scale view of galaxy formation and evolution. Its data reveal the physical links between a galaxy’s structure, its star-formation history, and its cosmic environment, connecting all phases of galactic life into a single, coherent picture. Euclid is transforming our understanding of the Universe’s “tuning fork,” showing how galaxies light up with star formation, collide, and fade — and how, at their hearts, black holes and stellar cores evolve together.

Source: Max Planck Institute for Astrophysics/News

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Contacts:

Dr. Maximilian Fabricius
Leader German Science Data Center SDC-DE
Tel: +49 89 30000-3712
Fax: +49 89 30000-3569
mxhf@mpe.mpg.de
Max Planck Institute for Extraterrestrial Physics

Prof. Dr. Roberto Saglia
Scientist OPINAS
Tel: +49 89 30000-3495
saglia@mpe.mpg.de
Max Planck Institute for Extraterrestrial Physics

Dr. Christoph Saulder
Postdoc OPINAS
Tel: +49 89 30000-3774
csaulder@mpe.mpg.de
Max Planck Institute for Extraterrestrial Physics

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Further Information

Euclid opens a treasure trove of data: MPE plays a crucial role in exploring the dark universe

March 19, 2025

The first Euclid data published by ESA (Q1) provide impressive insights into the depths of the universe. They include high-resolution images of 26 million galaxies, reveal the finest structures and make it possible for the first time to precisely determine the shape and distance of more than 380,000 galaxies. This data is a milestone and yet only marks the beginning of research into dark matter and dark energy. And the Max Planck Institute for Extraterrestrial Physics (MPE) plays a central role in all of this.

more

Zoom into the first page of Euclid’s great cosmic atlas

October 15, 2024
Euclid reveals the first deep view into the cosmos, spanning an area of 500 full moons in the sky.

more

MPE-built optical assembly fully integrated on EUCLID-NISP

December 21, 2018

Last week at LAM Marseille, the optical assembly consisting of the camera lens assembly “CaLA” and the corrector lens assembly “CoLA” have been fully integrated on the near-infrared optics NISP for the Euclid satellite. Euclid is an ESA mission, planned to launch in 2022 to study the “Dark Universe”. Scientists at the Max Planck Institute for Extraterrestrial Physics are responsible for the overall optical design of the near-infrared instrument NISP NI-OA.

more

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Ageing stars may be destroying their closest planets

This artist’s impression depicts a dying Sun-like star engulfing an exoplanet. New research published in Monthly Notices of the Royal Astronomical Society suggests that ageing stars may be destroying the giant planets orbiting closest to them.

Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Garlick/M. Zamani
Licence type: Attribution (CC BY 4.0)

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Ageing stars may be destroying the giant planets orbiting closest to them, new research shows – offering a glimpse into the possible fate of the likes of Jupiter and Saturn in our own solar system.

Once stars like the Sun run out of hydrogen fuel, they cool down and expand to become red giants. In the Sun's case this will happen in about five billion years.

In the new study, published in Monthly Notices of the Royal Astronomical Society, researchers looked at nearly half a million stars that had just entered this "post-main sequence" phase of their lives.

The team of astronomers at University College London (UCL) and the University of Warwick identified 130 planets and planet candidates (i.e., that still need to be confirmed), including 33 that were previously unknown, orbiting closely around these stars.

They found such planets were less likely to occur around stars that had expanded and cooled enough to be classed as red giants (i.e. that were further on in their post-main sequence evolution), suggesting many of these planets may already have been destroyed.

Lead author Dr Edward Bryant, of Mullard Space Science Laboratory at UCL and the University of Warwick, said: "This is strong evidence that as stars evolve off their main sequence they can quickly cause planets to spiral into them and be destroyed. This has been the subject of debate and theory for some time but now we can see the impact of this directly and measure it at the level of a large population of stars.

"We expected to see this effect but we were still surprised by just how efficient these stars seem to be at engulfing their close planets.

"We think the destruction happens because of the gravitational tug-of-war between the planet and the star, called tidal interaction. As the star evolves and expands, this interaction becomes stronger.

"Just like the Moon pulls on Earth's oceans to create tides, the planet pulls on the star. These interactions slow the planet down and cause its orbit to shrink, making it spiral inwards until it either breaks apart or falls into the star."

Co-author Dr Vincent Van Eylen, of Mullard Space Science Laboratory at UCL, said: "In a few billion years, our own Sun will enlarge and become a red giant. When this happens, will the solar system planets survive? We are finding that in some cases planets do not.

"Earth is certainly safer than the giant planets in our study, which are much closer to their star. But we only looked at the earliest part of the post-main sequence phase, the first one or two million years of it – the stars have a lot more evolution to go.

"Unlike the missing giant planets in our study, Earth itself might survive the Sun's red giant phase. But life on Earth probably would not."

For their study, the researchers used data from NASA's Transiting Exoplanet Survey Satellite (TESS). They used a computer algorithm to search for the repeated dips in brightness that indicate an orbiting planet is passing in front of the star, focusing on giant planets with short orbital periods (i.e., that took no more than 12 days to orbit their star).

The team began with more than 15,000 possible signals, and applied rigorous tests to rule out false signals, eventually whittling this number down to 130 planets and planet candidates. Of these, 48 were already known, 49 were already identified as planet candidates (i.e., they still need to be confirmed), and 33 were new candidates detected for the first time.

The team found that the more advanced a star's evolution, the less likely it was to host a nearby giant planet.

The overall occurrence rate of such planets was measured at just 0.28%, with the youngest post-main sequence stars showing a higher rate (0.35%) similar to that of main sequence stars, and the most evolved stars, which had cooled and swelled enough to be classed as red giants, dropping to 0.11%. (For this analysis, the researchers excluded the smallest 12 of the 130 identified planets.)

From the TESS data, researchers can estimate the size (radius) of these possible planets. To confirm them as planets rather than planet candidates, astronomers must rule out the possibility of these bodies being low-mass stars or brown dwarfs ("failed stars" whose core pressure is not high enough to start nuclear fusion) by calculating their mass.

This can be done by precisely measuring the movements of their host stars and inferring the gravitational tug of the planets (and therefore their mass) from wobbles in these movements.

Dr Bryant added: "Once we have these planets' masses, that will help us understand exactly what is causing these planets to spiral in and be destroyed."

The researchers received funding from the Science and Technology Facilities Council (STFC).

Source: Royal Astronomical Society (RAS)/News

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Media contacts

Sam Tonkin
Royal Astronomical Society
Mob: +44 (0)7802 877 700
press@ras.ac.uk

Dr Robert Massey
Royal Astronomical Society
Mob: +44 (0)7802 877 699
press@ras.ac.uk

Mark Greaves
University College London
m.greaves@ucl.ac.uk

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Science contacts:

Dr Edward Bryant
University of Warwick
edward.m.bryant@warwick.ac.uk

Dr Vincent Van Eylen
University College London
v.vaneylen@ucl.ac.uk

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Images & captions

Dying star engulfing a planet

Caption: This artist’s impression depicts a dying Sun-like star engulfing an exoplanet. New research published in Monthly Notices of the Royal Astronomical Society suggests that ageing stars may be destroying the giant planets orbiting closest to them.

Credit: International Gemini Observatory/NOIRLab/NSF/AURA/M. Garlick/M. Zamani

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Further information

The paper ‘Determining the impact of post-main sequence stellar evolution on the transiting giant planet population’ by Edward M Bryant and Vincent,hr Van Eylen has been published in Monthly Notices of the Royal Astronomical Society. DOI: 10.1093/mnras/staf1771.

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Notes for editors

About the Royal Astronomical Society

The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science.

The RAS organises scientific meetings, publishes international research and review journals, recognises outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

Keep up with the RAS on Instagram, Bluesky, LinkedIn, Facebook and YouTube.

Submitted by Sam Tonkin on Wed, 05/11/2025 - 13:07

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Particle Physics in Space: In Search of the Elusive Axion

Composite image of the Sun including high-energy X-ray data from NuSTAR (blue); low-energy X-ray data from Hinode (green); and ultraviolet data from Solar Dynamics Observatory (red). The centers of stars like or even bigger than our Sun are unimaginably hot environments that may hold the key to detecting dark matter. Download Image

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NuSTAR is best known for observing some of the hottest, brightest, and most extreme phenomena in the Universe, such as supernovae explosions and the immediate surroundings of black holes. But did you know that it can also be used to search for some of the smallest and most elusive particles in existence?

For decades we've known that a large portion of the mass in the Universe—even more than all the stars and galaxies that we can see—consists of dark matter. We know it's there because we can see its gravitational effects on the matter we can observe—just like we can't see air but can see its effect on the world around us when trees sway in the wind. But dark matter itself, like its name suggests, is invisible to us, as it does not give off or interact with light. This makes trying to find out what it's actually made of incredibly difficult.

Axions

Many different kinds of particles and objects have been put forward as possible candidates to be dark matter, one of which is the axion. If you think that sounds a bit like the name of a cleaning product, you'd be right—it was named after a laundry detergent brand because it 'cleans up' a messy problem in particle physics called charge-parity violation. Under the Standard Model of particle physics, the laws of physics apply in the same way to particles and their corresponding anti-particles. But if this were the case, why is there so much more matter in the Universe than anti-matter? Axions present a possible solution to this problem and would emerge naturally from the breaking of this matter/anti-matter symmetry.

If axions were to exist, they would be extremely light and interact so weakly with normal matter that trillions could pass through you every second and you wouldn't even notice. This also makes them a compelling candidate for dark matter. However, if we are to demonstrate that this theorized particle exists, first we need to detect it. And that's no small feat, since there is a wide range of possible masses and degrees to which they interact with light or matter that could apply to an axion—in other words, they might be out there but we're not exactly sure what they look like. Axions are so elusive that all ground-based efforts to date have failed to detect them. So, scientists have turned to space to continue the search.

The Sun as a Particle Physics Laboratory

Inside our own Sun, high-energy X-ray photons released in the thermonuclear core face a long, slow journey to the surface, repeatedly absorbed and re-emitted by the densely packed matter inside, losing energy along the way until they finally emerge as visible light thousands to millions of years later. However, the interaction of a high-energy photon with the electric fields of an atomic nucleus or electron could also generate an axion, which then streams directly out of the Sun. Once outside, the axion interacts again with the Sun's magnetic field and can turn back into a photon. Depending on the properties of the axion, this could be an X-ray photon.

This is where NuSTAR comes in. Unlike most sensitive X-ray astrophysics observatories, NuSTAR is able to safely look at the Sun, making it useful for studying flares and hotspots on the Sun's surface. Scientists can also use this Solar data to look for the distinct predicted signatures of axions.

So far, NuSTAR has not detected an axion signal from the Sun. In science, a non-detection is not bad news! Since we know a lot about the Sun's properties, we know that if axions were larger or more interactive than certain values, we would have detected them. The fact that we haven't allows us to rule out certain possibilities for those properties. If axions exist, they must be sufficiently light and non-interactive that the signal from the Sun is too weak to detect.

The next step is to find somewhere that might produce a stronger axion signal than the Sun. Axion emission is directly related to the temperature inside a star. In other words, we're going to need a bigger, hotter star.

Let's go bigger!

On the left shoulder of Orion is an enormous red supergiant star called Betelgeuse, the tenth-brightest star in our night sky. Hundreds of times larger than the Sun, its radius would engulf the orbit of Mars if it were in our Solar system. The temperature of its core is also far higher than the Sun's, implying that it could be a far more efficient source of axions. In 2019, NuSTAR observed Betelgeuse in search of signs of a specific theorized axion production mechanism that Betelgeuse is hot enough to achieve—the de-excitation of iron nuclei. This kind of atomic transition happens at a very specific energy, meaning that the axion-to-photon transformations in the Sun’s outer magnetic field would result in a distinctive X-ray emission line at 14.4 keV.

While the 14.4 keV line was not detected from Betelgeuse, this doesn’t imply that axions cannot exist. Once more, the lack of a signal instead rules out certain possible properties of axions, providing orders of magnitude better constraints on their mass and the strength of their interactions with normal matter than we could achieve with the Sun.

Since axions weren't detected from Betelgeuse, can we find an even bigger, hotter laboratory than that? What if we didn't just look at one star, but a whole galaxy of hot massive stars?

M82, also known as the Cigar Galaxy for its narrow, edge-on shape, is a nearby galaxy undergoing intense star formation, meaning that it is full of newly formed, very massive and very hot stars. If each of these stars could potentially be giving off a very faint axion signal, then by observing the galaxy NuSTAR could pick up their combined signal. This would appear as a high-energy X-ray glow around the galaxy.

"By analyzing over a million seconds of NuSTAR X-ray observations of M82, we found no excess X-ray signal attributable to decaying axions," said Francisco Rodríguez Candón, PhD student at the University of Zaragoza in Spain and the first author of a paper on this new approach. "This null result enabled us to set some of the strictest limits to date on axion properties."

Once more, no signal was detected—which means that we can rule out further swaths of possible combinations of axion mass and photon coupling from the potential axion parameter space. Little by little, we are narrowing down the possibilities and, if axions are truly what makes up dark matter, closing in on their nature.

In the meantime, the search for axion signals continues. These studies demonstrate the importance of using astronomical observations with X-ray telescopes to probe particle physics in environments and on scales that would be impossible to replicate on Earth. With the help of telescopes like NuSTAR, the Universe itself is our particle physics laboratory.

Source: NASA's Nuclear Spectroscopic Telescope Array (NuSTAR)/News Release

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The Hidden Efficiency of Stellar Interactions

Artist’s impression of the evolution of a binary system with mass transfer. The left panel represents the initial state, where two regular, main-sequence stars orbit each other. The middle panel shows the mass transfer process, where the more massive star evolves faster and expands, thereby throwing mass onto the other. The right panel shows the present-day configuration consisting of a stripped star and a rapidly rotating star. Credit: Navid Marvi, courtesy of the Carnegie Institution for Science

The observational constraints on the mass transfer efficiency are in conflict with theoretical models. The main panel shows the available constraints for each of the 16 binary star systems, which shows a preference for stars to accrete 30-90% of the transferred mass. The top panel shows histograms of the predictions of theoretical models. The rotationally limited model (in red) predicts very little mass accretion, namely below 10% of the transferred mass. The thermally limited model (in orange) predicts a bimodal distribution with an accretion efficiency of either below 20% or 100%. Both of these models, which are the main ones used in a larg.e number of theoretical studies and predictions for stellar populations, are therefore in conflict with the observations. © MPA

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When two stars orbit close together, one star can transfer material to its companion, dramatically changing both stars' evolution. However, how much of this transferred material actually stays with the receiving star has remained one of the biggest mysteries in binary star physics. Using a new sample of 16 carefully studied binary systems, MPA scientists have now discovered that binary stars are much more efficient at keeping transferred material than previously thought, with many systems retaining more than half of the mass that was donated. This finding challenges decades of theoretical assumptions and has profound implications for our understanding of stellar evolution, affecting everything from the types of supernovae we observe to the formation of gravitational wave sources, X-ray binaries, and exotic stellar objects like blue stragglers.

Most stars in the Universe are born in binary or multiple star systems, where two or more stars orbit around their common center of mass. When these stars orbit close enough together, over the course of their lifetimes, they can interact gravitationally and exchange material. This can dramatically alter the evolution of both stars, leading to exotic stellar objects, different types of supernovae, and the formation of compact objects like neutron stars and black holes. Therefore, binary interactions play a key role in shaping the stellar populations we observe.

The research team focused on a special type of binary system called Be+sdOB binaries, which consist of a "stripped" star that has lost its outer layers, and a rapidly rotating star that was spun up by accreting these outer layers (see Figure 1). These systems are particularly valuable for studying mass transfer because they represent clear examples of past binary interaction. The stripped star reveals how much mass was originally donated, while the other star shows how much was actually retained.

Previous studies have successfully measured the masses of both stars in 16 such systems using a combination of state-of-the-art observational techniques. Namely, high-resolution interferometry from the CHARA Array and VLTI/GRAVITY instruments creates a powerful virtual telescope by combining light from multiple telescopes, allowing them to measure the tiny separations and orbital motions of close binary stars. These interferometric measurements, combined with detailed spectroscopic observations, enabled precise mass determinations. By comparing these present-day masses with stellar evolution models, the team at MPA could determine how much mass must have been transferred and retained during the binary interaction.

The results are striking: half of the systems require that more than 50% of the transferred mass was retained by the receiving star. This is in stark contrast to theoretical models that assume only a few percent of transferred material can be kept, based on the idea that rapidly rotating stars cannot accept much additional mass due to centrifugal forces (see Figure 2).

The most likely explanation for this efficient mass transfer is that accretion disks around the receiving star can carry away angular momentum while allowing matter to fall onto the star. This process, well-known in other astrophysical contexts, appears to be much more important in binary star evolution than previously recognized.

These findings will force a major revision of binary evolution models and have wide-ranging implications. Many high-profile theoretical predictions about stellar evolution rely on the assumption that mass transfer is highly non-conservative, which these findings are in strong tension with. The results suggest that mass-gaining stars will be much more massive than currently predicted, leading to different populations of supernovae, white dwarfs, and gravitational wave sources. The orbital properties of post-interaction binaries will also be affected, which provides important constraints for understanding the formation of exotic stellar objects.

Source: Max Planck Institute for Astrophysics/Research Highlights

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Contacts:

Thibault Lechien
PhD student
Tel: 2001
lechien@mpa-garching.mpg.de

Selma E. de Mink
Director
Tel: 2041
sedemink@mpa-garching.mpg.de

Original publication

Thibault Lechien, Selma E. de Mink, Ruggero Valli, Amanda C. Rubio, Lieke A. C. van Son, Robert Klement, Harim Jin, and Onno Pols
Binary Stars Take What They Get: Evidence for Efficient Mass Transfer from Stripped Stars with Rapidly Rotating Companions

ApJL 990 L51

Source | DOI

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Revisiting an unusual spiral

NGC 4102

A spiral galaxy. The inner region immediately around the bright centre is golden in colour. A gap separates this region from a bright ring, itself surrounded by a glowing halo. Strands of dark brown dust swirl around the centre and the outer ring, joined in one spot by a curved arm. Bright, blue and pink specks of light dot the ring, showing where stars are concentrated or have recently formed. Credit: ESA/Hubble & NASA, G. Fabbiano

>What lies at the heart of this unusual-looking spiral galaxy? The galaxy NGC 4102, featured in this ESA/Hubble Picture of the Week, is home to what astronomers call an active galactic nucleus. Active galactic nuclei are luminous galactic centres powered by supermassive black holes that contain millions to billion times the mass of our Sun. As these black holes ensnare gas from their surroundings and draw it close with their intense gravitational pull, the gas becomes so hot that it begins to glow and emits light from X-ray to radio wavelengths.

At a distance of just 56 million light-years away in the constellation Ursa Major (The Great Bear), NGC 4102 provides an ideal opportunity to study the ways in which active galactic nuclei interact with their home galaxies. Active galactic nuclei come in many different flavours, from extremely powerful types that consume massive amounts of matter and shoot out jets of charged particles, to calmer types that sip gas from their surroundings and glow more faintly.

NGC 4102 likely falls into the latter category. It’s classified as Compton-thick — a way of saying that its nucleus is obscured by a thick layer of gas — and a LINER, or low-ionisation nuclear emission-line region. LINER galaxies are identified by emission lines from certain weakly ionised elements, and they can be powered by a supermassive black hole that is lazily collecting gas from around it.

A previous image of this galaxy, made from data taken with Hubble’s Wide Field Planetary Camera 2 (WFPC2), was released in 2014. This new version presents an upgraded view of the galaxy, using data from the Wide Field Camera 3, which replaced WFPC2 in 2009 and improved upon its resolution and field of view. The new observations come from a programme that will combine visible-light images from Hubble with X-ray information from the Chandra X-ray Observatory to study the relationship between NGC 4102 and its active galactic nucleus.

Source: ESA/Hubble/potw

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Astronomers Map Mysterious “Dark” Gas in the Milky Way

This collection of images shows the location of the CO-dark molecular gas in the constellation Cygnus X, and NSF Green Bank Telescope data of the gas in the galactic latitude and longitude.Credit: NSF/AUI/NSF NRAO/P.Vosteen

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New research exposes CO-dark molecular gas, previously invisible to telescopes, uncovering the hidden building blocks of our Galaxy

An international team of astronomers has created the first-ever large-scale maps of a mysterious form of matter, known as CO-dark molecular gas, in one of our Milky Way Galaxy’s most active star-forming neighborhoods, Cygnus X. Their findings, using the U.S. National Science Foundation’s Green Bank Telescope (NSF GBT), are providing crucial new clues about how stars formed in the Milky Way.

For decades, scientists have known that most new stars are born inside clouds of cold molecular hydrogen gas. Much of this molecular hydrogen is invisible to most telescopes—it doesn’t give off light that can easily be detected. Traditionally, astronomers have hunted for these clouds by looking for carbon monoxide (CO), a molecule that acts like a flashing sign for star-building regions. However, it turns out there’s a lot of star-forming gas that doesn’t “light up” in CO. This dark, hidden material (called CO-dark molecular gas) has been one of astronomy’s biggest blind spots.

Now, for the first time, astronomers have mapped this hidden gas over a huge swath of sky—more than 100 times the area covered by the full Moon—by observing the radio spectral lines from atoms recombining, known as Carbon Radio Recombination Lines (CRRLs). The team’s map covers the bustling Cygnus X region, a cosmic metropolis about 5,000 light-years away, that’s overflowing with newborn stars.

“It’s like suddenly turning on the lights in a room and seeing all sorts of structures we never knew were there,” says Kimberly Emig, an associate scientist with the NSF National Radio Astronomy Observatory (NSF NRAO), and lead author of the new study.

The new map reveals a vast network of arcs, ridges, and webs of dark gas weaving through Cygnus X. These shapes show where star-making material is gathered and grown, before it becomes visible as before it becomes visible in CO as molecular clouds. The research demonstrates that these faint carbon signals, detected at very low radio frequencies, are an incredibly powerful tool for uncovering the hidden gas that directly connects ordinary matter with the formation of new stars. The study discovered that this dark gas is not just sitting still; it’s flowing and shifting, and moving with velocities much higher than previously realized. These turbulent flows can shape how quickly stars can form. The team also found that the brightness of these carbon lines is directly linked to the intense starlight bathing the region, highlighting the powerful role that radiation plays in galactic recycling.

“By making the invisible visible, we can finally track how raw material in our galaxy is transformed from simple atoms into the complex molecular structures that will one day become stars, planets, and possibly life,” Emig explains, “And this is just the beginning of understanding these previously unseen forces.” The NSF GBT has become the world’s premier tool for this kind of research, and even larger surveys of CRRLs (like the GBT Diffuse Ionized Gas Survey at Low Frequencies) are underway to explore other star-forming regions of the Milky Way. The insights gleaned here will help astronomers around the world model how our Galaxy—and potentially others—builds massive clouds for stars to form in.

Source: National Radio Astronomy Observatory (NRAO)/News

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About GBO

The Green Bank Observatory, part of the National Radio Astronomy Observatory, is a facility of the U.S. National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

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New image captures spooky bat signal in the sky

PR Image eso2518a
The RCW 94/95 nebulae in visible and infrared light

PR Image eso2518b
The RCW 94/95 nebulae in visible light

PR Image eso2518c
The RCW 94/95 nebulae infrared light

PR Image eso2518d
Wide-field view around the RCW 94/95 nebulae

PR Image eso2518e
The RCW 94/95 nebulae in the Circinus and Norma constellations

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Videos


PR Video eso2518a
Fly over a spooky cosmic bat


PR Video eso2518b
Travel to a bat-shaped nebula

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Image Comparisons


Compare the RCW 94/95 nebulae in visible and infrared light

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A spooky bat has been spotted flying over the European Southern Observatory’s (ESO’s) Paranal site in Chile, right in time for Halloween. Thanks to its wide field of view, the VLT Survey Telescope (VST) was able to capture this large cloud of cosmic gas and dust, whose mesmerising appearance resembles the silhouette of a bat.

Located about 10 000 light-years away, this ‘cosmic bat’ is flying between the southern constellations of Circinus and Norma. Spanning an area of the sky equivalent to four full Moons, it looks as if it's trying to hunt the glowing spot above it for food.

This nebula is a stellar nursery, a vast cloud of gas and dust from which stars are born. The infant stars within it release enough energy to excite hydrogen atoms around them, making them glow with the intense shade of red seen in this eye-catching image. The dark filaments in the nebula look like the skeleton of our space bat. These structures are colder and denser accumulations of gas than their surroundings, with dust grains that block the visible light from stars behind.

Named after a large catalogue of bright star-forming regions in the southern sky, the most prominent clouds here are RCW 94, which represents the right wing of the bat, and RCW 95, which forms the body, while the other parts of the bat have no official designation.

This stunning stellar nursery was captured with the VST, a telescope owned and operated by the Italian National Institute for Astrophysics (INAF) and hosted at the ESO’s Paranal Observatory in Chile’s Atacama Desert. The VST has the perfect capabilities to capture these large spooky creatures. Onboard it is OmegaCAM, a state-of-the-art 268-megapixel camera, which enables the VST to image vast areas of the sky.

This image was pieced together by combining observations through different filters, transparent to different colours or wavelengths of light. Most of the bat’s shape, including the red glow, was captured in visible light as part of the VST Photometric Hα Survey of the Southern Galactic Plane and Bulge (VPHAS+). Additional infrared data add a splash of colour in the densest parts of the nebula, and were obtained with ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA) as part of the VISTA Variables in the Vía Láctea (VVV) survey. Both surveys are open to everyone who wants to dive deep in this endless pool of cosmic photographs. Dare to look closer, and let your curiosity be haunted by the wonders that await in the dark. Happy Halloween!

Source: ESO/News

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More information

The European Southern Observatory (ESO) enables scientists worldwide to discover the secrets of the Universe for the benefit of all. We design, build and operate world-class observatories on the ground — which astronomers use to tackle exciting questions and spread the fascination of astronomy — and promote international collaboration for astronomy. Established as an intergovernmental organisation in 1962, today ESO is supported by 16 Member States (Austria, Belgium, Czechia, Denmark, France, Finland, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom), along with the host state of Chile and with Australia as a Strategic Partner. ESO’s headquarters and its visitor centre and planetarium, the ESO Supernova, are located close to Munich in Germany, while the Chilean Atacama Desert, a marvellous place with unique conditions to observe the sky, hosts our telescopes. ESO operates three observing sites: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope and its Very Large Telescope Interferometer, as well as survey telescopes such as VISTA. Also at Paranal, ESO will host and operate the south array of the Cherenkov Telescope Array Observatory, the world’s largest and most sensitive gamma-ray observatory. Together with international partners, ESO operates ALMA on Chajnantor, a facility that observes the skies in the millimetre and submillimetre range. At Cerro Armazones, near Paranal, we are building “the world’s biggest eye on the sky” — ESO’s Extremely Large Telescope. From our offices in Santiago, Chile we support our operations in the country and engage with Chilean partners and society.

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Links

• Photos of the survey telescopes at Paranal
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• New ESO analysis confirms severe damage from industrial complex planned near Paranal

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Contacts:

Juan Carlos Muñoz Mateos
ESO Media Officer
Garching bei München, Germany
Tel: +49 89 3200 6176
Email: press@eso.org

Bárbara Ferreira
ESO Media Manager
Garching bei München, Germany
Tel: +49 89 3200 6670
Cell: +49 151 241 664 00
Email: press@eso.org

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