In News:

An international team of astronomers has recently used South Africa’s MeerKAT Radio Telescope to identify a new giant radio galaxy (GRG) within the COSMOS field, as part of the MeerKAT International GHz Tiered Extragalactic Exploration (MIGHTEE) survey. The discovery, published on November 11, offers valuable insights into the formation and evolution of radio galaxies and the large-scale structure of the universe.

About the MeerKAT Radio Telescope

• Location: Situated in the Northern Cape province of South Africa, MeerKAT is a world-class radio interferometer operated by the South African Radio Astronomy Observatory (SARAO).
• Origin: Initially conceptualized as the Karoo Array Telescope (KAT) with 20 dishes, its scope was later expanded to 64 dishes, leading to its renaming as “MeerKAT” (meaning “more of KAT”).
• Specifications: Each dish measures 13.5 meters in diameter, spread across a maximum distance of 8 km.
• Technology: Signals received by individual dishes are transmitted to a central processor, allowing them to function collectively as a single, high-resolution telescope.
• Purpose:MeerKAT is a precursor instrument for the Square Kilometre Array (SKA) — the world’s largest and most sensitive radio telescope project, aimed at exploring the origin and evolution of the universe.
• Significance: Currently, MeerKAT is among the most powerful radio interferometers operating at centimetre wavelengths, enabling detailed observations of distant cosmic structures.

About Radio Galaxies

A radio galaxy is a type of galaxy that emits intense radio waves extending far beyond its visible boundaries. These emissions typically arise from jets and lobes of plasma produced by the galaxy’s active galactic nucleus (AGN), which is powered by a supermassive black hole.

The interaction of these jets with surrounding matter generates synchrotron radiation, making such galaxies prominent sources of radio emissions in the cosmos.

The Discovery: MGTC J100022.85+031520.4

Using MeerKAT’s advanced capabilities, astronomers identified a new giant radio galaxy (designated MGTC J100022.85+031520.4) within the COSMOS field.

Key Characteristics:

• Host Galaxy: Elliptical galaxy SDSS J100022.85+031520
• Redshift: Approximately 0.1034
• Size: About 4.2 million light years in projected length — qualifying it as a Giant Radio Galaxy (GRG)
• Mass: Nearly 93 trillion solar masses
• Radio Power:597 ZW/Hz at 1,284 MHz
• Age: Estimated 1 billion years
• Jet Power: Around 1 million QW
• Location: Identified as the Brightest Cluster Galaxy (BCG) within the galaxy cluster WHL J100022.9+031521

This makes it one of the few (around 4%) known GRGs that exist within a cluster environment rather than in isolated regions.