Galaxy hunters - Hungarian scientists help chart the universe

At an observatory in the hills above Budapest, Hungarian scientists are helping map the invisible. Their work with the European Space Agency's Euclid mission is charting how dark matter and dark energy shape the universe itself.

Under bright daylight, the dome of Budapest's Konkoly Observatory turns toward the sky. Inside, telescopes stand ready - not for tonight's stars, but for a universe being mapped from space.

András Kovács and his colleagues are part of a global effort to chart the cosmos - revealing where galaxies gather, where nothing exists, and how gravity connects it all.

"Euclid is systematically creating a map of about one-third of the whole night sky," Kovács said. "Counting the galaxies, taking photos of the night sky with exquisite precision from space - much better than from the ground."

The Hungarian team works with data sent by Euclid, a space telescope launched by the European Space Agency. From that stream of images, they are building a mirror image of the cosmos - a digital universe made of billions of galaxies and billions of years of history.

The virtual map contains 3.4 billion galaxies. By simulating how dark matter interacts across time and space, researchers are refining our understanding of how everything - from galaxies to gravity - connects, and how the universe is expanding.

As Euclid's data models unfold, something remarkable appears - a cosmic web. It's the universe drawn by gravity's hand, the first step in a mission that could redefine how humans see the heavens.

"When we look at distant galaxies, we see them as they were billions of years ago," Kovács said. "It's like looking back in time  watching the universe grow and expand."

Solving space mysteries

Each frame of data becomes a time capsule, showing how matter has shifted and stretched across billions of years.

"Dark matter causes deflections in the light of galaxies coming from the distant universe," Kovács said. "The amount of this lensing effect reveals the amount of dark matter."

By comparing those distortions across billions of galaxies, Hungary's researchers are helping decode how the universe bends - and why its expansion keeps speeding up.

"It's a privilege that now we can do this with a small team here and contribute to this international mission," Kovács said.

Each image Euclid sends feeds the map, pixel by pixel - a growing blueprint of creation.

"The universe may be infinite, but our ability to understand it isn't," Kovács said. "Still, every map we make brings that mystery a little closer."

Hungary's scientists may never touch the galaxies they're charting, but through their simulations, they're helping humanity trace the outlines of the unknown - one pixel at a time.