From ancient creeks of stars to the innards of white dwarfs, the Gaia Space Telescope has seen it all.
On Thursday, the European Space Agency’s mission specialists will send the low-fuel Gaia into orbit around the Sun, turning it off to astronomers around the world after more than a decade of service.
Gaia has been charting the universe since 2014, creating a vast encyclopedia of the position and movement of celestial objects from the Milky Way and beyond. It is difficult to grasp the breadth of development and discovery that a spinning observatory is enabled. But here are a few numbers: nearly 2 billion stars, millions of potential galaxies, and around 150,000 asteroids. These observations were brought Over 13,000 studies so far by astronomers.
Gaia changed the way scientists understand the universe, and that data became the reference point for many other telescopes on the ground and in the universe. Additionally, less than a third of the data collected has been released to scientists so far.
“It now supports almost everything in astronomy,” says Anthony Brown, an astronomer at Leiden University in the Netherlands, heading Gaia’s data processing and analysis group. “If you were to ask my astronomy colleagues, I don’t think they could have imagined that Gaia would have to do her research even if she wasn’t there.”
Starting in 2013, Gaia’s main goal was to uncover the history and structure of the Milky Way by constructing the most accurate, three-dimensional map of the position and velocity of 1 billion stars. As there is only a small portion of that data, astronomers Halo mass of dark matter We swallowed and identified our galaxy Thousands of trespassing stars ingested from another galaxy 10 billion years ago.
Dr. Brown measures continuous vibrations on the Milky Way disk and measures a kind of galactic seismology – evidence Of encounters with satellite galaxies that have put ourselves in orbit much more recently than scientists believed. That may be the reason for the Milky Way It looks distorted When viewed from the side.
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Source: www.nytimes.com
Gaia Announces Most Detailed Map of Milky Way to Date, Achieves Skyscan Milestone in Mission
Released on December 19, 2013, ESA's star mapping satellite “Gaia” We are now nearing the sky, but this does not mean the mission is complete. Technical tests are scheduled in the weeks before Gaia moves into its “retirement” orbit, with two major data releases scheduled for around 2026 and the end of the century, respectively.
An artist's impression of the Milky Way galaxy based on data from ESA's Gaia Space Telescope. Image credit: ESA / Gaia / DPAC / Stefan Payne-Wardenaar.
ESA Director of Science Carol Mandel said: “Today, as the science observations conclude, we celebrate this amazing mission that has exceeded all our expectations, extending almost twice its original predicted lifetime.” said.
“The treasure trove of data collected by Gaia has given us unique insight into the origin and evolution of the Milky Way galaxy, and has also provided insight into astrophysics and the solar system in ways we still don't fully understand. It transformed science.”
“Gaia is built on Europe’s unique excellence in astronomical measurements and will leave a lasting legacy for future generations.”
“After 11 years in space, surviving micrometeorite impacts and solar storms along the way, Gaia has completed collecting scientific data,” said Gaia project scientist Johannes Sahlmann.
“All eyes are now on preparing for the next data release.”
“We are excited to carry out this incredible mission and are excited about the discoveries that await us.”
An annotated artist's impression of the Milky Way galaxy, based on data from ESA's Gaia Space Telescope. Image credit: ESA / Gaia / DPAC / Stefan Payne-Wardenaar.
Gaia has used the three instruments many times over the course of its mission to observe and chart the stars' positions, distances, movements, changes in brightness, compositions, and numerous other characteristics.
This will allow Gaia to achieve its primary goal of building the largest and most accurate map of the Milky Way, displaying our home galaxy like no other mission has been able to achieve to date. is completed.
“Gaia has changed our impression of the Milky Way, so it contains major changes from previous models,” said Stefan Payne Waldenaar, a science visualizer at the House of Astronomy and the IAU Directorate of Astronomy Education. said.
“Even basic ideas such as the rotation of the galaxy's central bar, the distortion of the disk, the detailed structure of the spiral arms, and the interstellar dust near the sun have been revised.”
“Still, we are still speculating about the distant parts of the Milky Way based on incomplete data.”
“As more Gaia data is released, our view of the Milky Way will become even more accurate.”
Gaia's science and engineering teams are already hard at work preparing for Gaia Data Release 4 (DR4), scheduled for 2026.
The amount and quality of data is increasing with each release, and Gaia DR4, with an expected 500 TB data product, is no exception.
Additionally, it will cover the first 5.5 years of the mission, which is the length of the mission as originally planned.
“This is the release of Gaia that the community has been waiting for, but it's exciting considering it only covers half of the data collected,” said Dr. Antonella Valenari, an astronomer at the National Institute of Astronomical Sciences. Ta.
“Although the mission is currently suspending data collection, it will be business as usual for many years to come as we continue to make these impressive datasets available.”
Over the past decade, Gaia has accumulated more than 3 trillion observations of nearly 2 billion stars and other astronomical objects, revolutionizing the way we see our home galaxy and neighboring universe, and advancing its mission. You have completed the empty scan stage. Image credit: ESA / Gaia / DPAC / Stefan Payne-Wardenaar.
After several weeks of testing, Gaia will leave its current orbit around Lagrangian Point 2, 1.5 million km from Earth, away from the Sun and be placed into a final heliocentric orbit far from Earth's sphere of influence. .
The spacecraft is scheduled to be passivated on March 27, 2025 to avoid harm or interference with other spacecraft.
During the technical test, Gaia's orientation is changed, temporarily making it several orders of magnitude brighter and making it much easier to observe with small telescopes.
Gaia mission manager Uwe Lammers said: “Gaia will shine among the stars before her sad retirement and will treat us with this final gift to bid her farewell.”
“This is a moment to celebrate this transformative mission and to thank all the teams who have worked hard for more than a decade to operate Gaia, plan observations, and ensure the smooth return of valuable data to Earth.”
Source: www.sci.news
352 new binary asteroid candidates discovered by ESA’s Gaia mission
Binary asteroid systems have attracted the attention of the scientific community due to their intriguing properties and significant impact on our understanding of the Solar System. Unlike single asteroids, binary systems provide unique insights into many fundamental processes, including planetary formation and evolution, collision dynamics, and gravitational interactions.
Gaia has discovered possible moons around 352 asteroids that are not known to have companion stars. Image courtesy of ESA.
Asteroids are fascinating celestial objects that hold unique insights into the formation and evolution of our solar system.
Binary stars are even more fascinating because they allow astronomers to study how different objects in the universe form, collide, and interact.
With our unique all-sky scanning function, ESA's Gaia satellite Since its launch in 2013, it has made a number of important asteroid discoveries.
In Data Release 3, Gaia pinpointed the positions and movements of more than 150,000 asteroids. That precision has allowed scientists to probe deeper, looking for asteroids that exhibit a characteristic “wobble” caused by the gravitational pull of their orbiting companion stars.
Gaia has also collected data on the asteroid's chemistry, compiling the largest ever collection of asteroid reflectance spectra – light curves that reveal an object's color and composition.
More than 150,000 orbits determined in Gaia's Data Release 3 were refined as part of the mission's Focused Product Release last year, making them 20 times more accurate.
Gaia's upcoming Data Release 4 (due after mid-2026) is expected to reveal the orbits of even more asteroids.
“Binary asteroids are difficult to find because most are very small and far away from Earth,” said Dr Luana Liberato, an astronomer at the Observatory of the Côte d'Azur.
“Although just under one in six asteroids are predicted to have companion stars, only half a billion of the one million known asteroids have been found to be in binary systems.”
“But this discovery shows that there are many more asteroid moons still waiting to be discovered.”
“If confirmed, this new discovery adds 352 potential binary systems, nearly doubling the known number of moon-bearing asteroids.”
“Gaia is proving to be an excellent asteroid explorer, working hard to unlock the secrets of the universe, both within our solar system and beyond,” said Dr Timo Prusti, ESA's Gaia project scientist.
“This discovery highlights the Gaia data release as a major improvement in data quality and demonstrates the incredible new science made possible by this mission.”
a paper A paper describing the results has been published in the journal Astronomy and Astrophysics.
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L. Liberato others2024. Binary asteroid candidate in the Gaia DR3 astronomical measurements. A&A 688, A50;doi: 10.1051/0004-6361/202349122
This article was based on an original release from ESA.
Source: www.sci.news
