October 10, 2023
5937 view
61 like
Today, ESA’s Gaia mission unlocks a treasure trove of knowledge about our galaxy and beyond. Among other discoveries, star surveyors have revealed 500,000 new faint stars in massive star clusters, identified more than 380 potential cosmic lenses, and identified more than 150,000 asteroids in the solar system. The plan exceeded the odds of pinpointing the location.
Gaia maps our galaxy and beyond in incredible multidimensional detail, completing the most accurate stellar survey ever. Its mission is to provide a detailed picture of our place in the universe, allowing us to better understand the diverse objects within it.
Mission’s latest ‘Focused Product Release’ takes this even further, delivering many new and improved insights into the space around us. This release brings exciting and unexpected science. It is a discovery that goes far beyond what Gaia originally designed to discover and delve deeper into the history of the universe.
So what’s new from Gaia?
500,000 new stars: Expands Gaia observation mode and unlocks cluster cores
Gaia’s third data release (DR3) includes data on more than 1.8 billion stars, building a fairly complete view of the Milky Way and beyond. However, gaps remained in the mapping. Gaia has not yet fully explored regions of the sky where stars are particularly dense, and these regions remain relatively unexplored, causing stars that do not shine as brightly as many of their neighbors. I was looking down.
Globular clusters are a prime example. These star clusters are some of the oldest objects in the universe, making them especially valuable to scientists studying the universe’s past. Unfortunately, the star’s tightly packed, bright core can overwhelm telescopes trying to get a clear view. As a result, our cosmic map is left with a missing piece of the jigsaw puzzle.
To fill in the gaps in our map, Gaia chose Omega Centauri. Omega Centauri is the largest globular cluster visible from Earth and an excellent example of a “classic” star cluster. Instead of just focusing on individual stars as usual, Gaia now uses a special mode that allows it to actually map a wider part of the sky surrounding the center of a star cluster each time it comes into view. Did.
“At Omega Centauri, more than 500,000 new stars, never before seen by Gaia, have been discovered in just one star cluster.” Lead author from Germany’s Potsdam Leibniz Institute for Astrophysics (AIP) says Katja Weingrill, a member of the Gaia Collaborative.
“This is more than just filling a gap in the mapping, although that in itself is valuable,” added Alexei Mintz, also a co-author of AIP and a member of the Gaia Collaboration. “Our data enabled us to detect stars that are too close to be measured properly using Gaia’s normal pipeline. We will use the new data to explore the structure of the cluster, how its constituent stars are distributed, and more. A complete large-scale map of Omega Centauri that allows you to study where it is, how it moves, etc. We are taking full advantage of Gaia’s potential and we are using this amazing space tool to We deployed it with maximum power.”
This discovery not only meets Gaia’s projected potential, it actually exceeds it. The team used an observation mode designed to ensure all of Gaia’s equipment was operating smoothly. “We didn’t expect to use this for science, which makes this result even more interesting,” he adds.
A new star revealed at Omega Centauri marks one of the most crowded regions ever explored by Gaia.
Gaia is currently exploring eight additional areas in this way, and the results will be included in Gaia Data Release 4. These data help astronomers truly understand what’s going on inside these building blocks of the universe, and are an important step for scientists looking to confirm their ages. Identifying the center of our galaxy, determining whether there have been collisions in the past, examining how stars change over their lifetimes, constraining models of galactic evolution, and ultimately determining the age of the universe itself. guess.
Looking for a Lens: Gaia the Accidental Cosmologist
Gaia wasn’t designed for cosmology, but its new discovery makes it an elusive and exciting object that peers deep into distant space and holds clues to some of humanity’s biggest questions about the universe. I’m looking for a gravitational lens.
Gravitational lensing occurs when the image of a distant object is distorted by a disturbing mass, such as a star or galaxy, between us and the object. This intermediate mass acts as a giant magnifying glass, or lens, that can amplify the brightness of light and project multiple images of distant light sources into the sky. These strange and unusual configurations are visually interesting and have immense scientific value, revealing unique clues about the earliest times of the universe and its inhabitants.
“Gaia is a true lens seeker,” says co-author Christine Ducoulin of France’s Institute of Astrophysics in Bordeaux and a member of the Gaia collaboration. “Thanks to Gaia, we now know that some of the objects we see are not just stars, even though they look like stars. They actually have lenses that are very far away. Quasars are extremely bright and energetic galactic nuclei driven by black holes.There are currently 381 solid candidates for lenticular quasars, including 50 that are considered likely. It is a treasure trove for cosmologists and the largest set of candidates ever published at once.”
The research team identified candidates from an extensive list of possible quasars, including one from Gaia DR3. Five of the possible lenses could be Einstein crosses, and the cross-shaped hex is an unusual lens system with four distinct image components. (See 12 such configurations discovered by Gaia in 2021.)
Quasars with lenses are difficult to find. The images that make up the lens system can get stuck in the sky in a misleading way, and most of them are so far away that they are faint and difficult to spot.
“The great thing about Gaia is that it’s ubiquitous, so you don’t have to know where to look to find the lens,” said co-author Laurent Galluccio of France’s Cote d’Azur University. adds. With this data release, Gaia becomes the first mission to achieve a high-resolution all-sky survey of gravitational lenses. ”
Extending Gaia’s value to cosmology has synergies with ESA’s recently launched Euclid mission to explore the dark universe. Although both focus on different parts of the universe, Euclid focuses on mapping billions of galaxies and Gaia focuses on mapping billions of stars, with the lens discovered by Gaia. Quasars can be used as a guide for future exploration by Euclid.
Asteroids, stacked starlight, pulsating stars
Other papers published today provide further insight into the space around us and the diverse and sometimes mysterious objects within it.
One will reveal more about about 156,823 of the asteroids identified as part of Gaia DR3. The new dataset pinpoints the locations of these rock bodies over nearly twice the previous timespan and makes most of their orbits 20 times more accurate based on Gaia observations alone. In the future, Gaia DR4 will complete the set and include comets, planetary moons, and twice as many asteroids as him, improving our knowledge of small celestial bodies in nearby space.
Another paper maps the Milky Way’s disk by tracking weak signals seen in starlight, faint traces of gas and dust floating between stars. To study these signals, the Gaia team stacked up 6 million spectra, forming an incredibly large dataset of weak features never before measured in such a large sample. Did. With this data set, scientists hope they will eventually be able to narrow down the source of these signals, which the research team suspects is a complex organic molecule. Learning more about where this signal comes from will help us study the complex and intertwined physical and chemical processes at play across galaxies and understand more about the matter between stars.
Last but not least, we have a paper characterizing the dynamics of 10,000 pulsating and binary red giant stars in the largest database available to date. These stars are part of a catalog of 2 million variable star candidates published in Gaia DR3, which helps us calculate cosmic distances, see star signatures, and learn how stars evolve throughout the universe. This is the key to figuring out. New releases give you a deeper understanding of how these fascinating stars change over time.
“This data release further demonstrates the broad and fundamental value of Gaia, even on topics it was not originally designed to address,” said Timo Prusti, ESA’s Gaia project scientist.
“Despite its primary focus on star surveyors, Gaia has researched everything from rocky bodies in our solar system to quasars in images billions of light-years away, far beyond the edge of the Milky Way. This mission is to provide true exploration.” With unique insight into the universe and the objects within it, we are exploring its wide, all-sky perspective on the surrounding sky to its fullest. I use it to the fullest. ”
next step
Gaia’s previous data release, Gaia DR3, took place on June 13, 2022. This was the most detailed survey of the Milky Way to date, and it was a treasure trove of data about strange “starquakes,” asymmetrically moving stars, stellar DNA, and more. Gaia DR3 includes new and improved details about nearly 2 billion stars in the Milky Way, including binary stars, thousands of Solar System objects, and millions more beyond our galaxy. It contained the largest catalog of galaxies and quasars.
The mission’s next data release, Gaia DR4, is expected to be released by the end of 2025. It builds on both Gaia DR3 and this interim focused product release to further our understanding of the multidimensional Milky Way Galaxy. It refines knowledge about the colors, positions and movements of stars. Resolve variable and multi-star systems. Identify and characterize quasars and galaxies. List candidates for exoplanets. more.
Check here for the latest information on Gaia’s release timeline.
Notes for editors
More information about this release, known as Gaia’s Focused Product Release or FPR, can be found below.
Documents that make up a Gaia-focused product release:
For more information, please contact us below.
ESA For Media Members
Email: media@esa.int