Throughout history, the universe has remained an enigma, captivating the curiosity of humanity since time immemorial. The quest to understand its origin has spurred countless questions and inspired numerous discoveries. In a remarkable revelation, astronomers, akin to cosmic detectives, have unveiled a cosmic secret hidden within the depths of the Milky Way. Leveraging observations from the European Space Agency’s Gaia space telescope, they have identified two early streams of stars, named ‘Shakti’ and ‘Shiva’ after Hindu deities.
These celestial formations offer a tantalizing glimpse into the galaxy’s primordial past, serving as ancient relics that illuminate its earliest epochs, billions of years ago. Through meticulous observation and analysis, astronomers have pieced together the cosmic puzzle, revealing insights into the intricate tapestry of the universe’s formation. With each discovery, humanity edges closer to unravelling the mysteries of the cosmos, unlocking the secrets of its ancient origins and expanding our understanding of the universe’s vast and wondrous expanse.
Envision a vast cosmic canvas depicting the Milky Way, adorned with billions of stars interwoven amidst clouds of gas and dust, stretching across the infinite expanse of space. Within this intricate tapestry lie remnants of galaxies from more than 12 billion years past, entwined with our fledgling Milky Way through cosmic mergers. Among these celestial formations, Shakti emerges as a cluster of stars sharing a chemical composition akin to other stellar components, blending seamlessly into the cosmic fabric. In contrast, Shiva stands out as a distinct thread, weaving its way through the stellar ensemble, a unique element embedded within the celestial weave, enriching the cosmic narrative with its singular presence.
Astronomer Khyati Malhan, the primary investigator behind the study published in the Astrophysical Journal, underscores its importance in tackling a fundamental query in modern astrophysics: The genesis of galaxies as astronomical entities. Focusing on the Milky Way, a sprawling cosmic entity spanning about 100 thousand light years adorned with luminous spirals, it potentially harbours insights into this celestial enigma. Thus, by interpreting Shiva and Shakti as vestiges from the galaxy’s nascent phases, astronomers gain insight into the formative processes preceding the development of its distinctive disk structure. This perspective offers a pathway to understanding the intricate mechanisms underlying galactic evolution, shedding light on cosmic narratives shaping the universe’s grand tapestry.
This remarkable feat was accomplished through the European Space Agency’s (ESA) Gaia space telescope, launched in 2013 with the explicit objective of creating a more precise 3D map of the Milky Way than ever before. Utilizing Galileo’s precise instruments, it conducted measurements of positions, distances, and motions of celestial bodies with unparalleled accuracy, leading to the discovery of Shakti and Shiva and their movements. Situated approximately 30,000 light years away from the galactic centre, these stars originated during the early stages of the galaxy’s formation. Serving as witnesses to the galaxy’s nascent era, these stellar streams provide invaluable insights into its evolutionary history and the processes that shaped its development. Through Gaia’s meticulous observations, astronomers have unlocked a treasure trove of data, unravelling the mysteries concealed within the vast expanse of our cosmic home.
In Hindu cosmology, Shiva and Shakti symbolize the dual forces of creation and destruction, believed to arise from their divine union, shaping the fabric of the universe. Similarly, the recognition of Shiva and Shakti within the ancient stellar streams of the Milky Way resonates with the cosmic mythologies depicting the genesis of the cosmos. This symbolic association holds profound significance in unveiling the galaxy’s primordial origins, bridging the realms of science and spirituality. The identification of these celestial entities offers a unique perspective on the cosmic narrative, intertwining scientific inquiry with the profound mysteries of creation, fostering a deeper understanding of the universe’s intricate tapestry.
Shiva and Shakti exhibit a distinct molecular composition compared to other celestial bodies in the night sky. Classified as ‘metal-poor’, they contain lower quantities of heavy elements such as iron, carbon, and oxygen. This unique characteristic suggests that they have maintained their original properties since the early stages of universal formation, over a billion years ago. The absence of significant elemental enrichment indicates their ancient age and pristine nature, harkening back to a time when stars were first forged in the crucible of cosmic evolution. Their composition serves as a tangible link to the distant past, offering valuable insights into the primordial conditions that prevailed during the universe’s infancy. Through the study of Shiva and Shakti, astronomers glean glimpses of the celestial processes that shaped the cosmos, unraveling the intricate tapestry of cosmic history woven across billions of years.
In her presentation, Malhan addressed the challenges encountered in investigating the early stages of the Milky Way, likening the process to an ongoing, 13-billion-year-long movie that remains unfinished. The narrative surrounding the birth and evolution of our galaxy remains ambiguous, with numerous enigmas awaiting resolution. Looking ahead, the forthcoming Gaia mission holds promise in shedding further light on this cosmic saga. The universe persists as a vast puzzle awaiting unravelling, and astronomers, through their persistent exploration and observation, endeavour to decipher more of the Milky Way’s mysteries each passing day. Their efforts contribute to the ever-expanding body of knowledge about the universe, illuminating the intricacies of cosmic evolution and enriching our understanding of the cosmos. As humanity delves deeper into the mysteries of space, the quest for answers propels us toward a greater comprehension of our place within the vast expanse of the cosmos.
All Images Courtesy: European Space Agency
The cosmic interplay between Shiva and Shakti, celestial entities tasked with upholding the balance of cosmic energy, delineates the cycles of creation and destruction within our galaxy. Their identification marks a pivotal milestone, bridging the realms of mythology and science to deepen our comprehension of the Milky Way’s origins. This fusion of ancient narratives and empirical inquiry yields a masterpiece that evokes profound wonder and contemplation. As we peer into the vast expanse of space, we gain a deeper appreciation for the interconnectedness between humanity and the universe. Here, mythical symbolism converges with scientific inquiry, echoing back to the dawn of time itself. This symbiotic relationship invites us to explore the cosmic tapestry woven with threads of legend and observation, illuminating the intricate dance of celestial forces that shape our understanding of existence. Through this exploration, we come to recognize our inherent connection to the cosmos and the enduring legacy of curiosity that propels us toward greater cosmic understanding.
* The writer is Associate Professor, Department of Physics, University of Lucknow.
