Goa PIO leads the NASA team to find the farthest galaxy group

PANAJI: An international team of NASA-linked astronomers, led by a scientist of Indian origin born in Goa, Vithal Tilvi, discovered a group of galaxies never seen before, now labeled, which is the farthest group of galaxies that has ever been sighted

In 2013, Tilvi was also part of a team that discovered the farthest galaxy ever seen by astronomers. It is estimated that the new group of galaxies, EGS77, is more than 13 billion light years from Earth. It took Tilvi and his team more than four years to make the findings.

This group of galaxies can now help astronomers see the universe directly in their childhood, and see what the chemicals were present when the universe was just born. “As we look more and more, we look back in time. This is because the starlight that carries information about the group of galaxies is coming to Earth now, after traveling for 13 billion years, ”Tilvi told TOI.

It is usually difficult to see galaxies up to EGS77 due to the presence of neutral hydrogen fog in the universe, which blocks part of the galaxy's light, said James Rhoads of NASA, a team member.

Fortunately, the intense heat of these same galaxies clears the surrounding hydrogen mist, allowing the light of the galaxy to travel freely to Earth. Galaxies and the group of galaxies such as EGS77 must have cleared all the hydrogen mist, which leads to the transition from the opaque universe to a transparent one we see today. This is a tremendous achievement and will advance our knowledge about how the universe evolved, Tilvi said.

In 2013, Tilvi's team discovered the farthest galaxy

The findings of the discovery of EGS77 are first presented on January 5, at the American Astronomical Society conference in Hawaii.

While this is the first group of galaxies identified as responsible for cleaning the hydrogen mist, future NASA missions will tell us much more, said Sangeeta Malhotra of Nasa, co-author of the article The Beginning of Cosmic Reionization: Evidence of a Bubble ionized Just 680 million (millions of years) after the Big Bang. ”

In 2013, Tilvi was part of a team that discovered the farthest galaxy in the universe and, in 2017, led a team of astronomers who discovered the first black hole candidate in the universe.

Currently, he is the project leader for a NASA-funded project to study this black hole using observations taken by the Hubble Space Telescope. Tilvi is also part of NASA's Wide Field Infrared Prospecting Telescope (WFIRST) team, which will be launched in 2025.

The distance of EGS77 from Earth means that it is at the limit of what can be observed using the best current technology on a platform such as the Hubble Space Telescope.

“The current telescopes we have, such as the Hubble Space Telescope, were not meant to discover galaxies so far. But we are pushing the limits. In another year and a half, the James Webb Telescope will be launched, which is much larger than the Hubble Space Telescope, and our plan is to use this new telescope to see groups like EGS77, ”said Tilvi.

Currently, Tilvi is a visiting researcher at the School of Earth and Space Exploration, at Arizona State University, USA. UU., And is contributing to the State Council of Higher Education of the Goa government as a professor of research, development and innovation.