Gaia accuracy

It’s time to take stock Gaiathe European Space Agency’s most detailed construction mission 3D map of our galaxy. The European Space Observatory, which sees an important Italian contribution, has in fact achieved this Decade. It is an anniversary that actually leads us to evaluate the results achieved so far. To date, Gaia’s goals have reached beyond expectations: since its launch, it has become… December 19, 2013 Aboard the Soyuz-Fregat aircraft carrier, the mission proved to be an essential tool for unraveling the many mysteries that still surround the Milky Way. Starting with the wonderful “tenants”: there are approx Two billion stars Analyzed from the Gaia catalogue, with unprecedented measurement detail.

This is evidenced by one of the many studies carried out thanks to Gaia data, which on its tenth anniversary day is a symbol of proof Accuracy Achieved by the European mission. A team of astronomers led byEffl (École Polytechnique Fédérale de Lausanne) in Switzerland actually used Gaia measurements to accurately estimate the distance from Earth of several thousand stars. research, Posted on Astronomy and astrophysicsProvides important data about one of the most difficult phenomena to measure in astronomy: the view. This is the phenomenon by which an object appears to change its position depending on the observation point – in our case, the ground observation point.

“Stellar parallax is a measurement based on the angle formed by ‘triangulation’ between Gaia’s position in space, the Sun and the star being studied,” he explains. Global Science Christina LetoProgram Director of the Italian Space Agency for the Gaia mission. “This is a very difficult measurement to get because it is a very small quantity, and it gets smaller and smaller the farther away the star is. The Gaia mission is capable of measuring angles up to 10 microarcseconds (about three billionths of a degree). By knowing the distance of a star, it is possible to know other basic properties such as its mass, age, and intrinsic luminosity. By measuring these quantities, Gaia can determine the structure of the Milky Way Galaxy and the history of its formation and evolution. Measuring parallax is complex, however there are small systematic effects that need to be verified and corrected.”

if studio Led by EPFL, which also sees the participation of Italian researchers from the University of Bologna and INAF, it focuses specifically on parallax correction. To date, Gaia has increased the number of stars whose eclipse can be measured by a factor of 10,000: this has allowed a large Accuracy gain Compared to its European predecessor, the mission Hipparchus From the European Space Agency. In the new research, scientists applied techniquesAstroseismologyor study Oscillations excellentTo measure the distance from Earth of the thousands of stars observed by Gaia more accurately.

«Using astroseismology – continues Cristina Lehto – the research team measured the distance of tens of thousands of stars with extreme precision and compared them with those in Gaia’s EDR3 to verify the accuracy of the parallaxes reported by Gaia. The proposal of this research is that the techniques used could be useful for improving Gaia parallax measurements. “But certainly the study also highlights the quality and extreme accuracy of the measurements produced by the mission.”

Please attach your CV to the letter 2020the Gaia 3 early data release (Turn3) provided the scientific community with a goldmine of data, which was then combined into 2022 With the Gaia data release 3 (D3). Now we wait until the end 2025 the Gaia Data Release 4 (DR4), which will further enrich Gaia’s exceptional 3D catalog.

“After 10 years of operational mission – says Cristina Lehto – the European Space Agency has extended the Gaia mission until the end of 2025. It will be possible to obtain a catalog based on 12 years of observations, Gaia DR4, and it is expected that the accuracy achieved by Gaia measurements will “It improves parallax uncertainties and reduces systematic effects.”

So, all that’s left is to celebrate this decade of Gaia’s successes, while we wait for the next targets to get an increasingly accurate picture of our galactic home.