Astronomers are dizzy. The Gaia space telescope provided new data Monday on almost two billion stars in our Milky Way. The galaxy is alive and well thanks to its uncanny precision.
Gaia was launched in 2013 and is one of the most important scientific missions of European Space Agency (ESA). Its mission is to? Its goal is to map the galaxy in all dimensions and understand its structure, dynamics, and origin. The space observatory is equipped with two telescopes, and a one-billion pixel photographic sensor. It scans only a small fraction (less than 1%) of the stars in our galaxy, which has a diameter of 100,000 light years.
Gaia, 1.5 million kilometers away from Earth and opposite the Sun’s equator, is currently in its third harvest data. Astronomers were able, thanks to 2018’s second catalog to prove that our galaxy “merged” with another 10 billion years ago.
This third catalogue of observations, covering the period 2014-2017, will take five years to complete. The numbers revealed Monday are staggering: Gaia was able provide information about over 1.8 billion stars by analysing 700 million of the data that were sent to the ground each day for 34 months.
Anthony Brown, president and CEO of DPAC, an international consortium that processes the data stream sent from Gaia, rejoices at Gaia’s precision. Analyzing stars is like studying a fossil, since they are alive for billions of year. This allows us to find out more about the history of the galaxy’s formation.
Already, the telescope has provided a number of details such as these 220,000,000 photometric spectra which will allow us to determine for the first-time the mass, color and temperature of stars. This “DNA”, which contains 2.5 million new chemical compounds, provides information about the origins of stars and their journey through space. 35 million radial velocity, which measures the displacement of stars and offers a new understanding about the Milky Way’s movements.
Surprise for scientists: Gaia discovered for the first-time stellar “quakes”, which are tiny movements on the star’s surface that alter its shape. Conny Aerts (Belgium), who is part of the Gaia Collaboration, said that the discovery opened “a gold mine” for studying the “asteroseismology” of massive stars.
Francois Mignard is the scientific manager for Gaia in France. He says that the results of Gaia have shown a galaxy “much less turbulent” than anticipated. We thought she was in a stationary state. She was gently swirling about, much like a liquid gently stirred with an electric spoon. It didn’t happen! “, says the Observatory of the Cote d’Azur’s astronomer, who believes that Gaia surpasses all expectations at all levels.
She describes her “life as a patachon” as “a series of unexpected events and accidents.” Francois Mignard explains that the solar system does not rotate in a perpendicular direction. Instead, it moves up and down, above, and below. It also houses a diverse population of stars. Some of these stars may not have been there at the beginning but could have been “swallowed up”, thanks to interactions with nearby Sagittarius dwarf galaxies.
The new catalog provides unprecedented precision measurements for 156,000 asteroids within our solar system. It also breaks down the composition of 60,000. It hasn’t stopped revealing secrets about our galaxy. The final version of the catalog will be available only after Gaia has completed peering into space in 2030.
