Making new discoveries in our ever-expanding universe

I get lost in the stars.”

Giorgios Vernardos, assistant professor of astronomy

It’s not a bird, it’s not a plane, it’s Einstein’s Ring -- one of the newest discoveries of our universe – and a Lehman College professor was part of the team to help uncover this space phenomenon.

Georgios Vernardos, assistant professor of astronomy at the Bronx CUNY, is one of more than 1,500 members of the Euclid Consortium – a European space agency made of researchers working together on a “space mission to map the dark universe.”

"It's an unexpected finding,” Vernardos told The Press. “Something that was always there but we just needed to gain this new perspective."

The new perspective was gained by the Euclid telescope, launched into space by the consortium on July 1, 2023 and positioned 1.5 million kilometers from Earth, according to the European Space Agency website. With this launch, the researchers hoped to explore the composition and evolution of the dark universe and that’s exactly what they got.

The team discovered Einstein’s Ring, an optical illusion appearing as a ring of light – or more scientifically – a lens surrounding the NGC 6505 galaxy, 590 million light years away from our planet. The light that formed the ring came from a much more distant galaxy, 4.42 billion light-years away, according to the European Space Agency. This galaxy was previously invisible to researchers, hidden by the cosmic dust and obstacles, but thanks to the gravitational lensing effect of NGC 6505, scientists could see this distant galaxy in a way they never had before.

With such a close and accessible ring, astronomers could potentially study the dark matter between the two galaxies in ways they weren’t able to before. Dark matter, which constitutes a large portion of the universe's mass, doesn’t interact with light. It is invisible to telescopes that rely on visible light. But gravitational lensing, which is sensitive to all the mass and which the Euclid telescope uses, could provide the clearest look yet at how dark matter is distributed in space.

“I look at the data from Euclid as it comes in,” Bruno Altieri of the Euclid Consortium said in a written statement. “Even from that first observation, I could see it, but after Euclid made more observations of the area, we could see a perfect Einstein ring. For me, with a lifelong interest in gravitational lensing, that was amazing.”

According to Einstein’s theory of general relativity, the gravity of a massive object can bend light around it. This effect, known as gravitational lensing, is especially pronounced in galaxies and clusters of galaxies, which are heavy enough to bend the path of light from distant objects behind them. When the alignment is just right, the light from a distant galaxy can bend to form a perfect ring around the foreground object. Hence, Einstein’s Ring.

"The thing about gravitational lensing is that it’s not just a trick of the light," Vernardos added. "It’s a tool that allows us to study the entire mass of an object, whether it’s visible or not. And that’s crucial for understanding dark matter, which doesn’t emit light but has a massive impact on the galaxies we see today.”

Vernardos, who grew up in Greece, was a young boy when he became fascinated with the sky. He mentioned a neighbor who had a telescope on his roof and on one of his visits to look at the sky, Vernardos was fascinated by what he saw.

“I still remember asking him, ‘what are those things?’ and he told me, ‘It’s the moon,” Vernardos said with a smile on his face and a faraway look in is eye. He described his amazement at seeing the craters on the moon with such definition and being confounded by the idea that it wasn’t a flat surface, but a mass with dimensions.

Vernardos became assistant professor of astronomy at Lehman in September and moved into his new office this semester, which was sparse, short of a telescope and a globe of the cosmos on his desk. And of the more than 1,000 researchers part of the Euclid Consortium, he is the only one in in the Bronx and possibly New York City.

He hopes this discovery will inspire his students as they have access to the results because of Vernardos membership to the Euclid Consortium -- information that is not publicly. He hopes one day they will make discoveries of their own.

“I’m especially interested in solar system research,” said Lehman College senior, Shimon Wohlberg who is expected to graduate this May with a Bachelor of Science in physics. “The solar system is the next frontier of human exploration and I intend to pursue a career contributing to space exploration efforts.”

Moving to Harlem a few years ago and living in different parts of Europe and Australia his entire life, Vernardos says the rat race and bustle of NYC is prevalent. As for how he unwinds and escapes the madness of the city?

“I get lost in the stars,” he said.