Launched on 19 December 2013, Gaia’s gas tank is now approaching empty – it makes use of a couple of dozen grams of chilly gasoline per day to maintain it spinning with pinpoint precision. However that is removed from the tip of the mission. Know-how checks are scheduled for the weeks forward earlier than Gaia is moved to its ‘retirement’ orbit, and two large knowledge releases are tabled for round 2026 and the tip of this decade, respectively.

“As we speak marks the tip of science observations and we’re celebrating this unimaginable mission that has exceeded all our expectations, lasting for nearly twice its initially foreseen lifetime,” says ESA Director of Science Carole Mundell.

“The treasure trove of data collected by Gaia has given us distinctive insights into the origin and evolution of our Milky Means galaxy, and has additionally remodeled astrophysics and Photo voltaic System science in ways in which we’re but to completely recognize. Gaia constructed on distinctive European excellence in astrometry and can depart a long-lasting legacy for future generations.”

“After 11 years in area and surviving micrometeorite impacts and solar storms alongside the way in which, Gaia has completed gathering science knowledge. Now all eyes flip in direction of the preparation of the following knowledge releases,” says Gaia Challenge Scientist Johannes Sahlmann.

“I’m thrilled with the efficiency of this unimaginable mission, and excited concerning the discoveries that await us.”

Gaia delivers finest Milky Means map

Gaia has been charting the positions, distances, actions, brightness modifications, composition and quite a few different traits of stars by monitoring them with its three instruments many instances over the course of the mission.

This has enabled Gaia to ship on its main aim of constructing the most important, most exact map of the Milky Means, exhibiting us our house galaxy like no different mission has accomplished earlier than. As such, we now even have the most effective reconstructed view of how our galaxy may look to an out of doors observer. This new artist impression of the Milky Means incorporates Gaia knowledge from a large number of papers over the previous decade.

“It comprises main modifications from earlier fashions, as a result of Gaia has modified our impression of the Milky Means. Even fundamental concepts have been revised, such because the rotation of our galaxy’s central bar, the warp of the disc, the detailed construction of spiral arms, and interstellar mud close to the Solar,” says Stefan Payne-Wardenaar, scientific visualiser for the Haus der Astronomie, Germany, and the IAU Workplace of Astronomy for Training.

“Nonetheless, the distant components of the Milky Means stay educated guesses primarily based on incomplete knowledge. With additional Gaia knowledge releases our view of the Milky Means will change into much more correct.”

Discovery machine of the last decade

Gaia’s repeated measurements of stellar distances, motions and traits are key to performing ‘galactic archeology’ on our Milky Means, revealing missing links in our galaxy’s complex history to assist us study extra about our origins. From detecting ‘ghosts’ of other galaxies and multiple streams of ancient stars that merged with the Milky Means in its early historical past, to discovering evidence for an ongoing collision with the Sagittarius dwarf galaxy right now, Gaia is rewriting the Milky Way’s history and making predictions about its future.

Within the strategy of scanning the celebs in our personal galaxy, Gaia has additionally noticed different objects, from asteroids in our Photo voltaic System yard to galaxies and quasars – the brilliant and lively centres of galaxies powered by supermassive black holes – outdoors our Milky Means.

For instance, Gaia has supplied pinpoint precision orbits of greater than 150 000 asteroids, and has such high-quality measurements as to uncover possible moons round tons of of them. It has additionally created the largest three-dimensional map of about 1.3 million quasars, with the furthest shining vibrant when the Universe was only one.5 billion years previous.

Gaia has additionally found a new breed of black hole, together with one with a mass of nearly 33 times the mass of the Sun, hiding within the constellation Aquila, lower than 2000 light-years from Earth – the primary time a black gap of stellar origin this massive has been noticed inside the Milky Means.

“It’s spectacular that these discoveries are primarily based solely on the primary few years of Gaia knowledge, and plenty of have been made within the final 12 months alone. Gaia has been the discovery machine of the decade, a development that’s set to proceed,” says Anthony Brown, Chair of the Gaia Knowledge Processing and Evaluation Consortium (DPAC) and primarily based at Leiden College within the Netherlands.

Warning! Extra ground-breaking science forward

The Gaia scientific and engineering groups are already working full steam on the preparations for Gaia Knowledge Launch 4 (DR4), anticipated in 2026. The information quantity and high quality improves with each launch and Gaia DR4, with an anticipated 500 TB of information merchandise, isn’t any exception. Moreover, it would cowl the mission’s first 5.5 years, similar to the size of the initially foreseen period of the mission.

“That is the Gaia launch the group has been ready for, and it’s thrilling to suppose this solely covers half of the collected knowledge,” says Antonella Vallenari, Deputy Chair of DPAC primarily based on the Istituto Nazionale di Astrofisica (INAF), Astronomical Observatory of Padua, Italy. “Although the mission has now stopped gathering knowledge, will probably be enterprise as common for us for a few years to come back as we make these unimaginable datasets prepared to be used.”

Gaia Knowledge Launch 4 is about to develop its binary star catalogue, the most important such catalogue up to now. Gaia has a singular potential to tease out the tiny motions of pairs of celestial objects orbiting shut to one another, and has already noticed beforehand hidden companions around bright stars.

By the way, Gaia’s last targeted observation, on 10 January, was of binary pair 61 Cygni. This iconic star attracted the eye of Nineteenth-century astronomers to yield a number of the first proper motion and parallax measurements, methods utilized by Gaia on some two billion stars.

Gaia’s exoplanet discoveries are additionally set to extend with the forthcoming datasets due to the longer timeframe of observations making it a lot simpler to spot ‘wobbling’ stars gently tugged by orbiting planets.

“Over the following months we’ll proceed to downlink each final drop of information from Gaia, and on the identical time the processing groups will ramp up their preparations for the fifth and closing main knowledge launch on the finish of this decade, protecting the total 10.5 years of mission knowledge,” says Rocio Guerra, Gaia Science Operations Workforce Chief primarily based at ESA’s European House Astronomy Centre (ESAC) close to Madrid in Spain.

“This may conclude an unimaginable coordinated effort between tons of of consultants throughout the science operations centre right here at ESAC, the mission operations crew flying Gaia from ESA’s European House Operations Centre in Germany, and the massive consortium of information processing specialists, who’ve collectively ensured the sleek working of this lovely mission for therefore lengthy.”

Gaia’s retirement plan

Whereas right now marks the tip of science observations, a brief interval of technology testing now begins. The checks have the potential to additional enhance the Gaia calibrations, study extra concerning the behaviour of sure expertise after ten years in area, and even support the design of future area missions.

After a number of weeks of testing, Gaia will depart its present orbit round Lagrange level 2, 1.5 million km from the Earth within the course away from the Solar, to be put into its closing heliocentric orbit, distant from Earth’s sphere of affect. The spacecraft shall be passivated on 27 March 2025, to keep away from any hurt or interference with different spacecraft.

Wave farewell to Gaia

Throughout the expertise checks Gaia’s orientation shall be modified, that means it would briefly change into a number of magnitudes brighter, making observations by small telescopes quite a bit simpler (it received’t be seen to the bare eye). A guide to locating Gaia has been set up here, and novice astronomers are invited to share their observations.

“Gaia will deal with us with this closing reward as we bid farewell, shining among the many stars forward of its well-earned retirement,” concludes Uwe Lammers, Gaia Mission Supervisor. “It’s a second to have fun this transformative mission and thank the entire groups for greater than a decade of onerous work working Gaia, planning its observations, and guaranteeing its valuable knowledge are returned easily to Earth.”