Dr. Chervin Laporte, a Distinguished Researcher at the Institute of Cosmos Science (ICCUB-IEEC), was awarded an ERC Starting Grant by the European Research Council (ERC) in its 2019 call for his project “Numerical Simulations of the Milky Way’s Accretion History (VIA LACTEA)”, which is officially starting today at the Institute of Cosmos Sciences of the University of Barcelona.

ERC Starting Grants, which are part of the program Horizon 2020, are designed to help talented researchers who want to establish their research teams in Europe. The awarded candidates must have an excellent scientific track record showing scientific talent and an excellent research proposal for the next five years. These are evaluated on the basis of excellence as the sole criterion by selected international peer reviewers.

About the project VIA LACTEA

The EU-funded VIA LACTEA project will investigate the formation process of the Milky Way. To achieve its goal, it will analyse its major accretion events using state-of-the-art computing techniques as well as the formation of the inner-halo. Secondly, it will look into the impact of known satellites. The project will build on the European Space Agency Gaia satellite’s three-dimensional map of the Milky Way, which shows that the stars in our galaxy are much more complex in structure and kinematics than previously thought.

The early third data release of the Gaia satellite has revealed much complexity in the structure and kinematics of stars in the Milky Way than previously appreciated. In the disc, Gaia has shown that our Galaxy is still enduring the effects of a collision that set millions of stars moving like ripples on a pond. In the stellar halo, the data uncovered a large single debris structure pointing to a massive accretion event 10 billion years ago, at a time when the disc was in its infancy. Our basic assumptions of dynamical equilibrium and axisymmetry at the basis of nearly all mathematical models of the Galaxy are now falling short to make further progress on our inference on the Galaxy’s formation or the distribution of dark matter. This proposal aims to explore the deep coupling between the stellar halo and the Milky Way disc and bulge, to gain new insights on the formation history of the Milky Way through its most major accretion events through a number of state-of-the-art computing techniques.

 In the words of Dr. Laporte, “The aim of his project is to constrain the accretion history of the Galaxy, and study how this influenced the formation and evolution of the Milky Way as well as the distribution of dark matter in the Galaxy through a series of numerical simulation campaigns. The predictions from these runs will be central for the interpretation of data from future and upcoming large photometric/spectroscopic surveys on the ground (WEAVE, SDSS-V, DESI, 4MOST and LSST at the Vera Rubin Observatory). As part of his project, I will also be joining the SDSS-V collaboration, which will map and measure chemical abundances and radial velocities for ~5 million stars in the Milky Way in both hemispheres and the WEAVE survey at La Palma.”

About Dr. Chervin Laporte

Among other recognitions, Dr. Laporte was awarded the Ramon y Cajal Fellowship in 2020. He has held postdoctoral fellowships at the Institute of the Physics and Mathematics of the Universe (IPMU) as a Kavli Fellow between 2020 and 2021, at the University of Victoria as a CITA National Fellow from 2017 to 2019 and a prize fellowship at the University of Columbia in the City of New York as a Junior Fellow of the Simons Society of Fellows (2014-2017).

Dr. Laporte began his academic journey at the University of Cambridge (2006-2010) where he took a degree in Natural Sciences and did his PhD at the Max Planck Institute for Astrophysics (2010-2014). His expertise covers a wide range of fields such as galactic dynamics, computational cosmology, galaxy formation and interpretation and data mining of large astronomical datasets. Throughout his career, Dr. Laporte has worked on dark matter on the scale of tiny dwarf galaxies to that of the largest bound objects in the Universe, galaxy clusters. He now primarily works on the formation and evolution of the Milky Way through a combination of numerical simulations and interpretation of large dataset (e.g. SDSS, Gaia) and dark matter on astrophysical scales.

Outside astrophysics, Dr. Chervin Laporte is a musician (jazz pianist) and enjoys scuba diving. One of the better outcomes of the COVID-19 pandemic was that it gave him the time to make more progress on improvisation with the support of his mentors in NYC and Maryland.

More information

Read the full description of the project «Numerical Simulations of the Milky Way’s Accretion History (VIA LACTEA)».

Palomar 5 is a unique star cluster. This is firstly because it is one of the “fluffiest” clusters in the halo of our Galaxy, with the average distance between the stars being a few light-years, comparable to the distance from the Sun to the nearest star. Secondly, it has a specular stellar stream associated with it that spans more than 20 degrees across the sky. In a paper published today in Nature Astronomy, an international team of astronomers and astrophysicists led by the University of Barcelona show that both distinguishing features of Palomar 5 are likely the result of an oversized black hole population of more than 100 black holes in the center of the cluster.

“The number of black holes is roughly three times larger than expected from the number of stars in the cluster, and it means that more than 20% of the total cluster mass is made up of black holes. They each have a mass of about 20 times the mass of the Sun, and they formed in supernova explosions at the end of the lives of massive stars, when the cluster was still very young” says Prof Mark Gieles, from the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) and lead author of the paper.
Tidal streams are streams of stars that were ejected from disrupting star clusters or dwarf galaxies. In the last few years, nearly thirty thin streams have been discovered in the Milky Way halo. “We do not know how these streams form, but one idea is that they are disrupted star clusters. However, none of the recently discovered streams have a star cluster associated with them, hence we can not be sure. So, to understand how these streams formed, we need to study one with a stellar system associated with it. Palomar 5 is the only case, making it a Rosetta Stone for understanding stream formation and that is why we studied it in detail” explains Gieles.

The authors simulate the orbits and the evolution of each star from the formation of the cluster until the final dissolution. They varied the initial properties of the cluster until a good match with observations of the stream and the cluster was found. The team finds that Palomar 5 formed with a lower black hole fraction, but stars escaped more efficiently than black holes, such that the black hole fraction gradually increased. The black holes dynamically puffed up the cluster in gravitational slingshot interactions with stars, which led to even more escaping stars and the formation of the stream. Just before it completely dissolves - roughly a billion years from now - the cluster will consist entirely of black holes.

Gieles points out that in this paper “we have shown that the presence of a large black hole population may have been common in all the clusters that formed the streams”. This is important for our understanding of globular cluster formation, the initial masses of stars and the evolution of massive stars. This work also has important implications for gravitational waves.

Palomar 5 is a globular cluster discovered in 1950 by Walter Baade. It is in the Serpens constellation at a distance of about 65,000 light-years, and it is one of the roughly 150 globular clusters that orbit around the Milky Way. It is older than 10 billion years, like most other globular clusters, meaning that it formed in the earliest phases of galaxy formation. It is about 10 times less massive and 5 times more extended than a typical globular cluster and in the final stages of dissolution.

Simulation showing the formation of the tidal streams of the Palomar 5 cluster and the distribution of blackholes. The stars are shown in yellow and the black holes in black.

A five-year quest to map the universe and unravel the mysteries of “dark energy” is beginning officially today, May 17, at Kitt Peak National Observatory near Tucson, Arizona, USA. To complete its quest, the Dark Energy Spectroscopic Instrument (DESI) will capture and study the light from tens of millions of galaxies and other distant objects in the universe.

By gathering light from some 30 million galaxies, project scientists say DESI will help them construct a 3D map of the universe with unprecedented detail. The data will help them better understand the repulsive force associated with “dark energy” that drives the acceleration of the expansion of the universe across vast cosmic distances.

What sets DESI apart from previous sky surveys? “DESI will allow us to see an order of magnitude more galaxies than ever before, and study the evolution of the Universe from 11 billion years ago to the present day”, explained Héctor Gil-Marín, a scientist at Institut de Ciències del Cosmos at the University of Barcelona (ICCUB) and at the Institute of Space Studies of Catalonia (IEEC), that will co-lead the first analysis of the galaxy maps. The DESI telescope collects light, or spectra, from galaxies and quasars, which get us their recession velocity. “We know that the farther the object is from us, the higher its recession velocity is, which allows us to build a 3D map of the universe”, Gil-Marín explained.

“DESI is the front runner of a new generation of instruments around the globe that will study dark energy from different angles,” said Andreu Font-Ribera, a cosmologist at Institut de Física d’Altes Energies (IFAE) that will co-lead the first analysis of the most distant quasars. He said the scientific program will allow researchers to address with precision two primary questions: what is dark energy; and the degree to which gravity follows the laws of general relativity, which form the basis of our understanding of the cosmos. “It has taken 10 years of effort, from the instrument design to this moment, when DESI starts collecting the data that is going to revolutionize our understanding of the Universe” says Violeta Gonzalez-Perez, a scientist at Universidad Autónoma de Madrid (UAM) that is one of the coordinators for developing computer simulations of what DESI will observe.

The disk of the Andromeda Galaxy (M31), which spans more than 3 degrees, is targeted by a single DESI pointing, represented by the large, pale green, circular overlay. The smaller circles within this overlay represent the regions accessible to each of the 5000 DESI robotic fiber positioners. In this sample, the 5000 spectra that were simultaneously collected by DESI include not only stars within the Andromeda Galaxy, but also distant galaxies and quasars. The example DESI spectrum that overlays this image is of a distant quasar (QSO) 11 billion years old. Credit: DESI collaboration and DESI Legacy Imaging Surveys

The formal start of DESI’s five-year survey follows a four-month trial run of its custom instrumentation that captured four million spectra of galaxies – more than the combined output of all previous spectroscopic surveys.

The DESI instrument resides at the retrofitted Nicholas U. Mayall 4-meter Telescope at Kitt Peak National Observatory, a program of the National Science Foundation’s (NSF) NOIRLab. The instrument includes new optics that increase the field of view of the telescope and includes 5,000 robotically controlled optical fibers to gather spectroscopic data from an equal number of objects in the telescope’s field of view.

“What is special about DESI is not so much the telescope, but the instrument” says Otger Ballester, an engineer at IFAE who has been part of the team developing the guiding, focusing and alignment cameras for DESI, one of the Spanish contributions to the project. In fact, the instrument “can simultaneously gather light from 5,000 different objects and obtain their spectra in just 20 minutes” Ballester said. As the telescope is moved into a target position, the optical fibers align to collect light from galaxies as it is reflected off the telescope mirror. From there, the light is fed into a bank of spectrographs and CCD cameras for further processing and study. On a good night, DESI collects spectra from some 150,000 objects.

Photo of a small section of the DESI focal plane, showing the one-of-a-kind robotic positioners. The optical fibers, which are installed in the robotic positioners, are backlit with blue light in this image. Credit: DESI collaboration

“The outstanding capability of DESI to collect spectra is also thanks to the instrument software,” said Santiago Serrano, an engineer at Institute of Space Sciences (ICE, CSIC) and IEEC, who has developed part of the algorithms needed to guide the telescope. He recognizes the invaluable effort of scores of scientists in Spain and around the world which have made the instrument and the experiment possible.

Spectra collected by DESI are the components of light corresponding to the colors of the rainbow. Their characteristics, including wavelength, reveal information such as the chemical composition of objects being observed as well as information about their relative distance and velocity.

As the universe expands, galaxies move away from each other, and their light is shifted to longer, redder wavelengths. The more distant the galaxy, the greater its “redshift.” By measuring galaxy redshifts, DESI researchers will create a 3D map of the universe. The detailed distribution of galaxies in the map is expected to yield new insights on the influence and nature of dark energy.

“Unraveling the properties of the mysterious Dark Energy is the main goal of DESI” said Licia Verde , ICREA professor at ICCUB. “We know that at present 70% of the energy content of the Universe is made of Dark Energy, but we know very little about its properties”.

Dark Energy determines the expansion rate of the universe , Verde explains. As the DESI instrument looks out in space and time, she says, “we can simultaneously observe the universe at different epochs, and by comparing them, figure out how the energy content evolves as the universe gets older.”

DESI is supported by the DOE Office of Science and by the National Energy Research Scientific Computing Center, a DOE Office of Science user facility. Additional support for DESI is provided by the U.S. National Science Foundation, the Science and Technologies Facilities Council of the United Kingdom, the Gordon and Betty Moore Foundation, the Heising-Simons Foundation, the French Alternative Energies and Atomic Energy Commission (CEA), the National Council of Science and Technology of Mexico, the Ministry of Economy of Spain, and by the DESI member institutions.

The DESI collaboration is honored to be permitted to conduct astronomical research on Iolkam Du’ag (Kitt Peak), a mountain with particular significance to the Tohono O’odham Nation.

Europe supports quantum science through the program Quantum Technologies Flagship, created to bring transforming advances to science, industry and society, and launch a solid industrial base based on the European tradition of excellence in quantum research. In this context, the 2021/2022 academic year launches the new master’s degree on Quantum Science and Technology.

Coordinated by the University of Barcelona, this master’s degree is the second one in Spain and the first one in Catalonia to major in this field. Among the participants are the Autonomous University of Barcelona, the Technical University of Catalonia, the Institute of Photonic Sciences (ICFO), the Barcelona Supercomputing Centre (BSC-CNS), the Institute of High Energy Physics (IFAE) and the Catalan Institute of Nanoscience and Nanotechnology (ICN2). The program, to be taught in English, is aimed at graduated students in Physics, Physics Engineering or related degrees, who want to continue their studies in this field. It will provide advanced knowledge to develop cutting-edge research on quantum science, from the theoretical side and the experimental branch in simulation, computing, sensors and communications.

On the one hand, communications and quantum sensors are part of the current economy, with products and services offered by specialized companies, which open new applications and new markets. On the other hand, computing and quantum simulation are under a research phase, but there are technological companies that are working on the first quantum computers for commercial uses that combine quantum computing and traditional ones. “Quantum physics will play an important role in the development of the near future, in our ability to estimate, communicate and measure in detail. For this reason, having a solid training in quantum sciences will be essential for promoting the limits of our knowledge and to develop new industrial products to benefit from the quantum properties”, notes Bruno Julià, lecturer at the Department of Quantum Physics and Astrophysics of the UB and coordinator of the master. “This master is the seed of a professional future in the field of quantum science”, adds the expert.

Apart from direct links to the industry through the QuantumCAT community, the new studies have the grouping of quantum technologies in Catalonia, which aim to promote synergies between different research centres and universities to strengthen the position of Catalonia as a distinguished region in quantum technologies. This link has enabled the participation of technological companies in the teaching program, as well as the promotion of the annual symposium of professional careers to facilitate the future integration of the students in the academic and the industrial sectors.

The fundamental objectives of the master’s degree are “on the one hand, to provide a solid education in theoretical physics and quantum information theory, and on the other, to offer a wide range of optional subjects to create a forward-looking study syllabus”, notes Julià, also member of the Institute of Cosmos Sciences of the UB.

The pre-enrolment period for the master’s degree is open until June 26. It also offers several grants. The course will start in September 2021 at the Faculty of Physics of the UB and will last a year (60 ECTS)..

Further information

From today on, the exhibition “Mars. The red mirror” can be seen in the room 2 in the Barcelona Center for Contemporary Culture (CCCB). The exhibition, which counted on the advice of researchers from the Institute of Cosmos Sciences of the UB (ICCUB-IEEC) and the contribution from the CRAI collection pieces.

This journey explores how we are linked to the red planet, from ancient times to date, through several approaches and disciplines. Science, arts and literature interact in a great exhibition project that explores our condition and future as a species. The exhibition coincides in time with three space missions –the first of them being NASA’s perseverance, whose probe arrived last February 18– that will promote knowledge on Mars and will open the window to new missions. The exhibition is structured into three big fields: Mars in ancient cosmos, Science and fiction in the red planet, and Mars in the Anthropocene. There are more than four hundred objects in the exhibition, among incunabula, sculptures, drawings, photographs, comics and even a Martian meteorite.

The Institute of Cosmos Sciences has collaborated in the definition of the exhibition since the beginning, through its director, Xavier Luri. As part of the exhibition, the activity Cosmos will take place on March 6: a conversation between Xavier Luri and ICCUB researcher Carme Jordi. There will be, in collaboration with CCCB, a session on the exploration of the space, with the participation of several UB institutes. The meeting will treat this topic from different perspectives, such as the economic and the technological ones. Carme Jordi will also take part in the ALIA Mission, an educational project by the CCCB for upper secondary education students. Its objective is to relate scientific dissemination to literary creation.

More information:

• IEEC's press release
• UB's press release

• Dr. Ferré-Mateu is one of the hundred researchers selected from around the world

• Homeward Bound project is a transformational leadership initiative for women with a background in STEMM from around the world

• The program will conclude with a three-week on-board ship voyaging to Antarctica

Dr. Ferré-Mateu, researcher at the Institute of Cosmos Sciences of the University of Barcelona (ICCUB), will be part of the sixth program along with a hundred researchers. The 12-month program comprises lectures, personal and leadership development tools, coaching sessions, visibility, training and the opportunity to develop meaningful collaborations – in forums, in teams with a focus on areas of interest, and in small diverse cohorts ending with a three-week on-board ship voyaging to Antarctica.

‘For me this journey to Antarctica represents the challenges we face as individuals and as a society.', commented Dr. Ferré-Mateu. ' Before we can think about reaching new worlds, we need to start taking care of our own, and I hope that the tools learnt during this journey will have an impact on the way we do science. It is one of the greatest adventures ever and I’m just thrilled to be part of it!’, she added.

What is the Homeward Bound project?

The Homeward Bound project was created in Australia in 2016. This project aims to build a global collaboration of 1000 women with backgrounds in STEMM for over ten years so they have the opportunity to take up leadership roles globally and to proactively contribute to a sustainable world, both individually and collectively. They will be visible, collaborative, networked and impacting the decisions made in many quarters for the greater good.

Who is Dr. Ferré Mateu?

Dr. Ferré Mateu’s research has been focused on the study of the cosmic evolution of galaxies of different types. They are a crucial building block to constrain the current galaxy formation and evolution paradigm. Moreover, to some degree, they are also a crucial piece of understanding a bit better the most fundamental question of human beings: where do we come from?

For this, she has been studying the fossil record of the stars in galaxies, to understand how they were and how they have evolved over cosmic time, in a similar way an archaeologist would reveal how the ancient populations lived by examining their remains. This quest has taken her to live, literally, all around the globe: the Canaries, Hawaii and Australia. This has allowed her to carry her science in forefront facilities while enjoying the wonders of such places by doing her favourite hobbies such as surfing, diving, hiking and traveling. Since 2018, Dr. Ferré-Mateu holds a Postdoctoral Junior Leader Fellowship at our institute, where she is one of the members of the Galaxy Structure and Evolution research group.

Her contribution to disseminating science to younger generations and advocating for women equity has become a very important part of her work participating in chats and events like Chatea con una Astrónoma motivating young girls into pursuing STEM careers or being part of "Journey through the Universe" that brings astronomy to the classrooms in Hilo, Hawaii.

You can follow her journey to Antarctica on Twitter or Instagram on the hashtag #AnnetainAntarctica.hb6 and her Instagram account @annetainantarctica.hb6

Links:

Dr. Ferré Mateu’s website

Homeward Bound project

Institute of Cosmos Sciences

Outreach events

Contacts:

ICCUB Communication Office

Barcelona, Spain

Esther Pallares

E-mail: secretariacientifica@icc.ub.edu

Dr. Anna Ferré Mateu

Barcelona, Spain

Institute of Cosmos Sciences

E-mail: aferremateu@icc.ub.edu

The Institute of Cosmos Sciences of the Universitat de Barcelona will use the December 2020 Early Data Release 3 (EDR3) of the European Space Agency mission Gaia to investigate Milky Way star formation and its interaction with its satellite galaxies, employing OCRE’s cloud resources for data mining, N-body simulations, and Bayesian techniques on the Gaia catalogue containing 1.8 billion sources.

Fifteen innovative research projects will benefit from commercial cloud solutions through EU cloud project Open Clouds for Research Environments (OCRE), demonstrating the effectiveness of cloud services in research.

€1.175 million will be distributed to the successful applicants, each receiving between €50,000 and €100,000. In its first call for the adoption of the cloud services available through the OCRE IaaS+ framework agreements, OCRE received 31 applications. All applications were screened by the OCRE cloud adoption funding team and overseen by the OCRE External Advisory Board.

The distribution of cloud adoption funding is a key milestone in OCRE’s goal of piloting a digital single market for cloud and digital services for European research. The research projects will be able to benefit from 27 different commercial cloud-based platforms that were sourced through the OCRE IaaS+ Tender concluded mid-2020 and will be made available in the OCRE Service Catalogue in the first quarter of2021.

Through this single procurement, thousands of research institutions across the European Research Area will be able to benefit from easy and procurement regulation-compliant access to commercial cloud services.

OCRE Adoption Funding Lead Jan Meijer (Uninett)said, “thanks to the good response to the call for projects we managed to assemble a balanced portfolio of 15 projects; showcasing the benefits of commercial cloud services on research outcomes from different angles. Our hope is that these showcases will inspire other researchers to follow in their footsteps and leverage the benefits of the OCRE portfolio of services for their research.”

More information about Gaia here.

• The new data allow us to determine that the ancient disc had a smaller extent compared to the Milky Way’s current disc size.

• Gaia provides the first measurement of the curvature of the Solar System’s orbit around the galaxy in the history of optical astronomy.

• The Gaia Catalogue of Nearby Stars has been released containing around 92 percent of the stars within 100 parsecs (326 light years) of the Sun.

The motion of stars in the outskirts of our galaxy hints at significant changes in the history of the Milky Way. This and other equally fascinating results come from a set of papers that demonstrate the quality of ESA’s Gaia Early third Data Release (EDR3), which is made public today.

Astronomers from the Gaia Data Processing and Analysis Consortium (DPAC) saw the evidence of the Milky Way’s past by looking at stars in the direction of the Galaxy’s ‘anticentre’. This is in the exact opposite direction on the sky from the centre of the galaxy.

The results on the anticentre come from one of the four ‘demonstration papers’ released alongside the Gaia data. The others use Gaia data to provide a huge extension to the census of nearby stars, derive the shape of the Solar System’s orbit around the centre of the Galaxy, and probe structures in two nearby galaxies to the Milky Way. The papers are designed to highlight the improvements and quality of the newly published data.

Join the events organized to celebrate the early gaia data release 3

To the galactic anticentre

The new Gaia data have allowed astronomers to trace the various populations of older and younger stars out towards the very edge of our galaxy – the galactic anticentre. Computer models predicted that the disc of the Milky Way will grow larger with time as new stars are born. The new data allow us to see the relics of the 10 billion-year-old ancient disc and so determine its smaller extent compared to the Milky Way’s current disc size.

The new data from these outer regions also strengthen the evidence for another major event in the more recent past of the galaxy.

The data show that in the outer regions of the disc there is a component of slow-moving stars above the plane of our galaxy that are heading downwards towards the plane, and a component of fast-moving stars below the plane that are moving upwards. This extraordinary pattern had not been anticipated before. It could be the result of the near-collision between the Milky Way and the Sagittarius dwarf galaxy that took place in our galaxy’s more recent past.

The Sagittarius dwarf galaxy contains a few tens of millions of stars and is currently in the process of being cannibalised by the Milky Way. Its last close pass to our galaxy was not a direct hit, but this would have been enough so that its gravity perturbed some stars in our galaxy like a stone dropping into water.

Using Gaia DR2, members of DPAC had already found a subtle ripple in the movement of millions of stars that suggested the effects of the encounter with Sagittarius sometime between 300 and 900 million years ago. Now, using Gaia EDR3, they have uncovered more evidence that points to its strong effects on our galaxy’s disc of stars.

“The patterns of movement in the disc stars are different to what we used to believe,” says Teresa Antoja, researcher at the Institute of Cosmos Sciences of the University of Barcelona, who worked on this analysis with DPAC colleagues. Although the role of the Sagittarius dwarf galaxy is still debated in some quarters, Teresa says, “It could be a good candidate for all these disturbances, as some simulations from other authors show.”

Measuring the Solar System’s orbit

The history of the galaxy is not the only result from the Gaia EDR3 demonstration papers. DPAC members across Europe have performed other work to demonstrate the extreme fidelity of the data and the unique potential for unlimited scientific discovery.

In one paper, Gaia has allowed scientists to measure the acceleration of the Solar System with respect to the rest frame of the Universe. Using the observed motions of extremely distant galaxies, the velocity of the Solar System has been measured to change by 0.23 nm/s every second. Because of this tiny acceleration, the trajectory of the Solar System is deflected by the diameter of an atom every second, and in a year this adds up to around 115 km. The acceleration measured by Gaia shows a good agreement with the theoretical expectations and provides the first measurement of the curvature of the Solar System’s orbit around the galaxy in the history of optical astronomy.

A new stellar census

Gaia EDR3 has also allowed a new census of stars in the solar neighbourhood to be obtained. The Gaia Catalogue of Nearby Stars contains 331 312 objects, which is estimated to be 92 percent of the stars within 100 parsecs (326 light years) of the Sun. The previous census of the solar neighbourhood, called the Gliese Catalogue of Nearby stars, was carried out in 1957. It possessed just 915 objects initially, but was updated in 1991 to 3803 celestial objects. It was also limited to a distance of 82 light years: Gaia’s census reaches four times farther and contains 100 times more stars. It also provides location, motion, and brightness measurements that are orders of magnitude more precise than the old data.

Beyond the Milky Way

A fourth demonstration paper analysed the Magellanic Clouds: two galaxies that orbit the Milky Way. Having measured the movement of the Large Magellanic Cloud’s stars to greater precision than before, Gaia EDR3 clearly shows that the galaxy has a spiral structure. The data also resolve a stream of stars that is being pulled out of the Small Magellanic Cloud, and hints at previously unseen structures in the outskirts of both galaxies.

At 12:00 CET on 3 December, the data produced by the many scientists and engineers of the Gaia DPAC Consortium become public for anyone to look at and learn from. This is the first of a two-part release; the full Data Release 3 is planned for 2022.

“Gaia EDR3 is the result of a huge effort from everyone involved in the Gaia mission. It’s an extraordinarily rich data set, and I look forward to the many discoveries that astronomers from around the world will make with this resource,” says Timo Prusti, ESA’s Gaia Project Scientist. “And we’re not done yet; more great data will follow as Gaia continues to make measurements from orbit.”

Gaia Mission

The Gaia satellite, which was launched in December 2013, is destined to create the most accurate map of the Milky Way. By making accurate measurements of the positions and motions of stars in the Milky Way, it is answering questions about the origin and evolution of our home galaxy.

Gaia EDR3 contains detailed information on more than 1.8 billion sources, detected by the Gaia spacecraft. This represents an increase of more than 100 million sources over the previous data release (Gaia DR2), which was made public in April 2018. Gaia EDR3 also contains colour information for around 1.5 billion sources, an increase of about 200 million sources over Gaia DR2. As well as including more sources, the general accuracy and precision of the measurements has also improved.

Participation of the Barcelona team

The ICCUB team (UB-IEEC), led by Professor Carme Jordi and professors Xavier Luri and Francesca Figueras, from the Department of Quantum Physics and Astrophysics, has participated in the Gaia mission from the beginning. Their role was focused on the scientific and technological design of the project, the development of the data processing system and the production of simulated data.

Regarding the now presented data, the Barcelona team coordinates the group that has developed the archive of the mission. It is also responsible for running several key processes for processing the data that arrives daily from the satellite, the first step in obtaining results for scientific use such as those now published. The group is also responsible for the process of pairing the various observations of the same star, and it collaborates in the calibration of star photometry and is fully involved in the scientific exploitation of the data. Finally, the Catalan researchers have played an important role in the performance verification papers, articles that are published together with the data and which verify their quality. Specifically, they have led four of these articles and have played a significant part in much of the rest.

The ICCUB Gaia team (UB-IEEC), made up of about thirty scientists and engineers, was awarded the 2013 City of Barcelona Award for Experimental Sciences and Technology. It is part of the Gaia Data Processing and Analysis Consortium, made up of more than 400 people from around twenty European countries, and leads the creation of the archive of the mission. Some of its members are part of the Gaia Science Team (GST), the ESA scientific advisory body.

More information:

• Gaia's webpage
• ICCUB's Gaia Team webpage
• Gaia ICCUB team detects a shake in the Milky Way
• Memory game
• Coloquio-tertulia sobre los datos de gaia - EDR3
• Gaia, la Galaxia en tus manos
• Institute of Cosmos Sciences (ICCUB)
• Teresa Antoja's webpage

Verification papers:
Gaia Early Data Release 3: The Gaia catalogue of nearby stars Gaia Collaboration, Smart, R.L., et al.
Gaia Early Data Release 3: Structure and properties of the Magellanic Clouds Gaia Collaboration, Luri, X., et al.
Gaia Early Data Release 3: The Galactic anticentre Gaia Collaboration, Antoja, T., et al.
Gaia Early Data Release 3: Acceleration of the solar system from Gaia astrometry Gaia Collaboration, Klioner, S.A., et al.

This Thursday, December 3, at 12 noon, the European Space Agency (ESA) will make a new data release from the Gaia mission with more than 1.8 billion observed objects. This is one of the great milestones expected by the astronomical community worldwide.

The different teams that make up the Gaia project will organize scientific seminars to explain the first obtained results and the lessons learned with the Gaia data, as well as a breakthrough in science that is beginning to appear. Data Processing and Analysis Consortium team (DPAC), which brings together more than 400 experts, is organizing an online meeting aimed at the scientific community, which will be coordinated by members of the Institute of Cosmos Sciences of the University of Barcelona (ICCUB).

Getting to know Gaia better: disseminative conference and memory game

On the same day, December 3, at 7 p.m., there will be an informative conference aimed at the general public, given by ICCUB researchers Josep Manel Carrasco and Mercè Romero. In the conference, they will explain how astronomy is revolutionizing the Gaia satellite, which provides unpublished clues about the origin and evolution of our galaxy, the Milky Way. They will describe the mission and explain Gaia’s strategy to observe the Universe by analysing the latest discoveries.

Also, the ICCUB team has created a Gaia memory game, which can be downloaded and printed, or played online. The twenty images in the game correspond to the space mission and are accompanied by descriptive texts.

Participation of the Barcelona team

TheICCUB team(UB-IEEC), led by Professor Carme Jordi and professors Xavier Luri and Francesca Figueras, from the Department of Quantum Physics and Astrophysics, has participated in the Gaia mission from the beginning. Their role was focused on the scientific and technological design of the project, the development of the data processing system and the production of simulated data.

Regarding the now presented data, the Barcelona team coordinates the group that has developed the archive of the mission. It is also responsible for running several key processes for processing the data that arrives daily from the satellite, the first step in obtaining results for scientific use such as those now published. The group is also responsible for the process of pairing the various observations of the same star, and it collaborates in the calibration of star photometry and is fully involved in the scientific exploitation of the data. Finally, the Catalan researchers have played an important role in the performance verification papers, articles that are published together with the data and which verify their quality. Specifically, they have led four of these articles and have played a significant part in much of the rest.

The ICCUB Gaia team (UB-IEEC), made up of about thirty scientists and engineers, was awarded the 2013 City of Barcelona Award for Experimental Sciences and Technology. It is part of the Gaia Data Processing and Analysis Consortium, made up of more than 400 people from around twenty European countries, and leads the creation of the archive of the mission. Some of its members are part of the Gaia Science Team (GST), the ESA scientific advisory body.

Quick flashes of light in the night sky have been linked to the growing mass of satellites and debris zipping around Earth’s orbit.

The orbital flashes, often mistaken for stars, occur 1,000 times an hour, according to new research led by the University of North Carolina at Chapel Hill that may improve the accuracy of astronomical data.

Stargazers have long been tantalized by the inexplicable glimmers and the study published Nov. 5 in The Astrophysical Journal Letters provides a potential explanation for those mysterious flashes.

Most of the flashes require powerful telescopes for viewing, but up to 100 of them are bright enough to see with the naked eye in a suburban community.

“Astronomical surveys have seen occasional reflected light glints from satellites; those flashes can cause false alarms in surveys looking for new events in the sky,” said lead study author Hank Corbett, graduate student at the UNC-Chapel Hill Department of Physics and Astronomy.

“For the first time, we have studied the flashes in a systematic way that will help reduce their impact on astronomical discoveries.”

The team at UNC-Chapel Hill, along with collaborators from San Diego State University and the University of Barcelona, reported more than 100,000 flashes over a six-month period.

The flashes were observed with the Evryscopes, telescopes in California and Chile constructed and funded by the National Science Foundation. The pair of robotic, gigapixel-camera telescopes observe the entire sky above their observatories every two minutes.

“These measurements allow us to predict the impact of reflected-light flashes on both current and future professional observatories and develop techniques to mitigate their effects on data,” Corbett said.

The orbital flashes are reflected not only from the satellites relied on for navigation, communication, weather forecasting, and more, but also from space trash such as dead satellites, paint chips and errant nuts and bolts that has accumulated since space exploration began six decades ago.

These short duration flashes can be indistinguishable from stars in images from professional observatories and are typically visible for only a fraction of a second.

“Millions of stargazers have likely observed these quick glimmers of light in the night sky,” Corbett said. “Reflected-light flashes happen so fast that observers may dismiss them as visual noise, but this research provides a potential explanation for those mysterious flashes.

Rogue reflections from Earth satellites take two forms: short duration flashes that can lead to mistaken astrophysical events and streaks associated with fast-moving or slowly rotating satellites like SpaceX Starlink.

Companies are competing to launch thousands of satellites capable of beaming internet coverage to Earth. However, in the new study, researchers conclude that the upcoming satellite internet constellations, like SpaceX Starlink, are unlikely to contribute significantly to the appearance of flashes, though there are other potential impacts of satellite constellations on astronomers.

Bright streaks caused by sun-illuminated satellites moving across an image are a separate class of events that needs to be studied.

Additional authors include Nicholas Law, Alan Vasquez, Ward S. Howard, Amy Glazier, Ramses Gonzalez, Jeffrey Ratzloff and Nathan Galliher, all of UNC-Chapel Hill, Octavi Fors of UNC-Chapel Hill and University of Barcelona and Robert Quimby of San Diego State University and University of Tokyo.