Astronomy is about expanding our knowledge and attempting to explore and understand what is beyond what we perceive. It is about understanding the nature of the universe and our place in it. You may imagine it’s not easy given the distance we are away from everything we are trying to understand. That is why we celebrate the feats made by our modern-day sophisticated technology. Here we are looking at one such feat made by our very own MeerKAT.
Perhaps accidentally, scientists discovered a gas cloud with some of the biggest hydrogen atoms in the universe known as the Rydberg atoms. This is the first discovery of such atoms outside the local universe. This discovery was made when light from the quasar PKS 1830-211 was intercepted at 7.3 billion light years on its way to earth. Think of a quasar as a very bright and highly active supermassive black hole spewing luminous jets from around its centre.
The PKS 1830-211 quasar, located about 11.1 billion light years from earth, is one of the brightest radio sources in the sky. This is because of the extremely powerful jets from its supermassive black hole that is pointed directly toward earth. As its light travelled towards earth, it lit up the arms of another other galaxy allowing these Rydberg atoms to be observed.
Rydberg atoms are essentially atoms with an electron in a high-energy state. This means the electron has more energy than normal. Under the right conditions, radio light magnifies these atoms and they become naturally occurring lasers. Conditions to observe this have previously been impossible in distant galaxies, however, MeerKAT has made it possible.
The Ryberg atoms can be used to study the physical and dynamic structure of galaxies.
Kimberly Emig, a Jansky Fellow at the National Radio Astronomy Observatory (NRAO) of the USA said that these atoms tell us that the interstellar gas in this new galaxy is much denser than that found in our Milky way galaxy. Interstellar gas is the gas filling the space between stars. Essentially, this interstellar gas consists of the ingredients to form stars and planets. Dense interstellar gas will have a large variety of organic molecules present.
“Such discoveries give a new way to observe our Universe and possibly study the evolution of interstellar gas in galaxies over cosmic time. They could also help us to understand how interstellar gas drives and inhibits the activity of supermassive black holes.” ~Kimberly Emig
A little bit more about MeerKAT
Meerkat is a 64-receptor radio telescope built in the Karoo desert of South Africa. It converts electromagnetic energy (radio waves) into data that scientists can process and analyse to help us understand and perceive more of the universe. If you’ve ever wondered if the name has anything to do with the likes of Timone from the Lion King, you weren’t thinking along the edges. The telescopes were to be named KAT for Karoo Array telescope which would consist of only 20 receptors, however after the budget was increased and 64 receptors could be built, they had to change the name to ‘Meer’ for ‘more’ to show that we now have more Karoo Array Telescopes, hence MeerKAT. This is also fitting because the karoo is the natural habitat of meerkats.