in 2013 The European Space Agency (ESA) has launched a unique space mission: Gaia Space Observatory, A spacecraft specifically designed for astrometry – the science of measuring the positions, distances and motions of stars With precision never seen before.
Scientists claim that The mission aims to build the largest and most accurate 3D spatial catalog ever created for the visible universe, With nearly two billion astronomical objects, most of them stars, but also planets, comets, asteroids and quasars, among other fascinating things from the vastness of space.
this week, The European Space Agency has released a new update of data collected by Gaia in the past three years, after it has observed 10 million stars and space objects, Which led to the publication of many scientific papers about some of the discoveries that were made. This data set has become Largest catalog so far From binary stars, thousands of objects in the Solar System, such as asteroids and the moons of planets, to the millions of galaxies and quasars that are outside the Milky Way.
One of the most surprising discoveries Gaia was unwittingly and without being the focus of her main mission to detect stellar earthquakes or “stellar earthquakes”, which consist of small movements recorded on the surface of a star Change its shape and can be made New insights into the inner workings of these distant suns.
Marcelo Miller Bertolami, an astronomer from La Plata and principal investigator at Conicet explained to Infobae. The work Gaia has been doing since its launch nearly 10 years ago. “Gaia is a European Space Agency space telescope that aims to determine the distance of stars with great accuracy. Watch the sky, see the exact locations of the stars. The Earth changes its position in space. So are the stars. Gaia is a rare medium telescope. It is not a conventional telescope, like the Hubble telescope. Its main advantage is how polished its silicon carbide mirrors are for observing stars and objects at great distances. It is polished at very high pressures: 10 nanometers, which is 10 millionths of a millimeter. The atoms are almost separatedMiller Bertolami explained.
“His work allows for many parallel studies, primarily about the stars and the origin of the Milky Way. By knowing the distance, one can know the intrinsic brightness of the stars. This will also allow us to improve the age of the stars and the history of our galaxy. Gaia measures each star multiple times. In addition to metering positions, it measures brightness. Measure several million stars multiple times. The astronomer added that, on average, each star will be measured about 70 times every two to four weeks, allowing us to monitor how its brightness changes.”
“The discovery of stellar earthquakes is surprising because the spacecraft was not designed to do such work.“, Confirmed reference to world astronomy, such as Dr. Connie Ayers from the Catholic University of Leuven, Belgium, at a European Space Agency (ESA) press conference on Monday 13 June, in which he participated Infobae. “These vibrations make the stellar gas move up and down. The brightness of the star changes with time. Then it makes the stars shine in the sky,” the expert continued.
“Thus it can be determined whether stars have pulsations. With the accuracy of Gaia, it is possible to determine the period of oscillation of stars.. They are differences in brightness that occur due to the star’s own vibration. And this vibration tells us about earthquakes or earthquakes. And depending on how it is made, based on its changing essence, it vibrates in different ways. When a star vibrates, there are differences in the star’s brightness over time. And it is this who is responsible for the study of stellar Venus, which is a very flourishing branch of astronomy these days.Miller confirmed.
The expert explained it Although the material in which stars are formed is usually the same, such as hydrogen and helium, over time the universe “gets dirty”, Because of the heavier chemical elements that can arise from material from planets, comets, asteroids and other dying stars. “Each star changes its internal chemical composition. The sun today has generated more helium than it did when it was born due to nuclear generation in the last 5 billion years as it was born,” Miller said.
The Stellar earthquakes were detected in a subset of observations focused on the distribution of variable stars in the Milky Way., that is, stars whose brightness changes over time. “Blinking stars provide astronomers with a very powerful tool for studying their internal physics and chemistry,” said Aerts. “It’s like earthquakes on the ground. Seismologists love earthquakes if they are not very violent, because they allow us to understand what is happening inside our planet. And seismologists do the same thing, but with the stars.”
In search of exoplanets
The data published by the European Space Agency has produced numerous published scientific studies. one of them It is the Argentine who participates in it Nicolás Unger, a UBA physics graduate and a PhD in astrophysics and exoplanets.
“I study the universe and look for planets outside our solar system. For this, Gaia is a very important task, because it not only generates the largest catalog of stars, Which today includes more than 1800 million, but it is also more accurate to measure their location, which is what we call astrometry in astronomy. This allows us to know where the stars are in the sky and the distance between them and us,” he explained. Submit to Infobae.
“These observations are very useful for finding exoplanets, because if one notices that if a star moves in a circular manner in the sky, then there is an object revolving around it. When analyzing the type of motion we can deduce whether it is a planet or another star orbiting it. The third edition of the Gaia data has recently been published, which includes the first catalog of exoplanets. “An investigation that I was able to participate in,” said the non-Earth specialist.
“Of all the stars Gaia observes, some are mined from what we think might host exoplanets. Those stars calculate what the orbit of that exoplanet will be. Therefore, we extract its orbit and pass it through a validation filter since today’s Gaia measurement is the first of its kind and needs permanent checks. My job is that. Gaia data review and validation. We do this by looking to see if this exoplanet has actually been detected by another method. So we use the radial velocity which consists of measuring the velocity of the star. If one sees the oscillatory motion in the star through time, we can infer the existence of an exoplanet. This is a very well-thought-out technique, as the first exoplanet was discovered, for exampleSelected Unger, who has been working with Gaia today in Geneva, together with collaborators from Italy and Spain.
In August 2015, Gaia completed its first year of scientific observations, During which 272 billion spot or astronomical measurements, 54.4 billion photometric data points, and 5.4 billion spectra were recorded. On September 14, 2016, the European Space Agency released the first Gaia dataset. Which included the locations and magnitudes of nearly a billion stars based on observations from July 25, 2014 to September 16, 2015.
On April 25, 2018, the European Space Agency published a second data set that included the locations of nearly 1.7 billion stars, In addition to measuring its total brightness at optical wavelengths. Now, with this third report, astronomers celebrate and pledge to reveal more surprises that Gaia has caught. Gaia’s data release on June 13 also contains the largest dataset ever compiled for binary star systems in our galaxy., that is, pairs of stars (or stars and black holes) that orbit each other. “This is something that is very interesting to the astronomical community because binary stars, for example, are the only way you can directly measure the mass of stars,” said Anthony Brown, an astronomer at Leiden University in the Netherlands.
The name Gaia was originally derived as an abbreviation for International Astrophysical Interferometer. This mirrors the optical interferometry technology that was originally planned for use on the spacecraft. Although the modus operandi has evolved during the studies and the acronym is no longer applicable, The Gaia name has been retained to give continuity to the project. The total cost of the mission is about $1 billion, Including manufacturing, launching and ground operations, for a mission that will take 15 years to complete. Although their reagents do not degrade as quickly as initially expected, the task can be extended.