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Depiction of the »Gaia« probe
Photo: HANDOUT/EPA
For the third time in ten years, the European Space Agency (ESA) has published a star catalogue.
The data collected by the "Gaia" probe show new and improved details for the 1.8 billion stars in our galaxy, ESA said on Monday.
Esa researchers have now used the data to create the most detailed map of the Milky Way to date (see photo gallery).
The Gaia space telescope was launched in late 2013.
"Gaia" measures the Milky Way in three dimensions - from a position one and a half million kilometers from Earth.
In 2016 and 2018, the researchers had already presented maps of the Milky Way based on "Gaia" data.
Initially, the catalog included "only" 1.15 billion stars.
By 2025, data from around two billion celestial bodies are to be collected.
The satellite has the largest digital camera ever built for space.
It has a resolution of almost a billion pixels.
The telescope can detect even tiny movements.
In addition, the brightness, temperature and chemical composition as well as the age of the almost two billion observed objects are also determined.
From the three-dimensional image of our galaxy, the researchers hope to gain new insights into the formation, origin and current appearance of the Milky Way.
New insights into starquakes
"In the last 34 months, Gaia has been able to gain many new insights and significantly expand the previous catalogue," explains Alessandra Roy, Gaia project manager at the German Space Agency at DLR.
One of the most surprising discoveries is that Gaia can detect so-called starquakes that change the shape of the stars, Esa reported.
These are "tiny movements on the surface of a star."
"Gaia" had previously recognized so-called radial oscillations.
These cause stars to periodically swell and shrink while maintaining their spherical shape.
Now, however, other vibrations have been discovered that "act more like large tsunamis," it said.
They only change the "global shape" of a star and are therefore not so easy to recognize.
"Gaia" is intended, among other things, to answer the questions of how exactly the spiral arms of our galaxy formed and which streams of matter flow through the Milky Way.
The probe was built by the space company Airbus Defense and Space.
The data sent by "Gaia" is received in the Esa ground stations in Cebreros, Spain, and New Norcia, Australia, via parabolic antennas.
sug/dpa