GS Paper: GS3

Central Idea

• European astronomers have unveiled the first images captured by the newly launched Euclid space telescope.
• These groundbreaking images offer a glimpse into Euclid’s extraordinary capabilities, demonstrating its capacity to observe billions of galaxies situated up to 10 billion light years away.

What is Euclid Mission?

• Euclid’s mission, led by the European Space Agency (ESA) in partnership with NASA, aims to unravel the enigmatic forces of dark matter and dark energy, which together constitute 95% of the universe.
• The Euclid Space Telescope is equipped with a 1.2-meter primary mirror, allowing it to capture detailed observations of galaxies.
• It carries two main scientific instruments: the visible-wavelength camera (VIS) and the near-infrared camera and spectrometer (NISP).
• By mapping the distribution and evolution of galaxies, Euclid aims to shed light on the fundamental forces shaping the cosmos.

(1) Mission Scope and Duration

• Euclid is a space-based mission, equipped with a sophisticated telescope and state-of-the-art scientific instruments.
• The mission is expected to have a nominal operational lifetime of 6 years, during which it will conduct an extensive survey of the sky.

(2) Launch and Spacecraft

• Euclid was launched on July 1, 2023, from Cape Canaveral in Florida using a SpaceX Falcon 9 rocket.
• The spacecraft carries the Euclid Space Telescope, which is designed to observe galaxies across a wide range of wavelengths.

(3) Investigating Dark Energy and Dark Matter  

• Dark energy, discovered in 1998, explains the unexpected acceleration of the universe’s expansion.
• Euclid’s mission aims to provide a more precise measurement of this acceleration, potentially uncovering variations throughout cosmic history.
• Dark matter, inferred through the gravitational effects it exerts on galaxies and clusters, plays a vital role in preserving their integrity.

Remarkable Images taken by Euclid

• Sharper and Clearer: These images are touted as the sharpest of their kind, showcasing Euclid’s precision and ability to capture intricate cosmic details.
• Perseus cluster: Euclid’s observations span four regions within our relatively nearby universe, including the massive Perseus cluster, which is located just 240 million light-years away and contains over 1,000 galaxies.
• Horseshoe Nebula: Euclid provided a unique perspective on celestial wonders like the Horsehead Nebula, a region where new stars are born.
• Dark Matter’s Clues: Scientists believe that organized structures like the Perseus cluster could only have formed if dark matter exists. Dark matter is inferred from its gravitational influence on galaxies, including their rotation and the formation of massive cosmic structures.

Unraveling the Dark Universe

• 5% Visible, 95% Dark: The mission emphasizes that our understanding of the universe is limited to merely 5%—the matter we can see. The rest of the universe remains “dark” because it does not emit electromagnetic radiation, but its effects on visible matter are evident.
• Dark Matter’s Role: Dark matter is suspected to influence galaxies’ rotation, galaxy clusters’ cohesion, and the formation of cosmic structures, further validating its existence.
• Dark Energy’s Mystery: Dark energy, an even more enigmatic force, was proposed in the 1990s when the universe’s accelerated expansion was discovered. This mysterious energy was awarded a Nobel Prize in 2011.

Mission Ahead

• Creating a 3D Map: Following its initial commissioning and overcoming technical challenges, Euclid will construct a 3D map covering approximately one-third of the sky. This map will reveal subtle variations attributable to the dark universe.
• Cosmic Web Exploration: By gaining insights into dark energy and dark matter, scientists aim to understand the formation and distribution of galaxies within the cosmic web, a network of cosmic structures that make up the universe.

Central Idea

• Recently, the Indian Astronomical Observatory (IAO) in Ladakh has astounded the world with mesmerizing images of a rare red-colored aurora, known as a Stable Auroral Arc (SAR).

What is Stable Auroral Arc (SAR)?

• Rare Phenomenon: SAR is a unique atmospheric occurrence witnessed during a potent G3-class geomagnetic storm.
• Unconventional Origins: Unlike typical auroras resulting from space borne charged particles colliding with the atmosphere, SAR arcs have a distinct genesis.
• Sign of Energy Flow: SAR arcs signify the transfer of heat energy into the upper atmosphere from Earth’s ring current system, a circular pathway carrying massive electrical currents encircling our planet.
• Geomagnetic Storm Influence: During the recent geomagnetic storm, the ring current was dynamically charged due to prolonged intense geomagnetic activity, leading to the manifestation of SAR arcs.
• Global Impact: This celestial event left its celestial mark across several regions worldwide.

How is it formed?

• Solar Wind Interaction: Aurora formation begins when the sun emits charged particles from its corona, creating solar wind. Upon colliding with Earth’s ionosphere, the mesmerizing aurora takes shape.
• Northern and Southern Counterparts: In the Northern Hemisphere, it’s recognized as the northern lights (aurora borealis), while in the Southern Hemisphere, it’s referred to as the southern lights (aurora australis).
• Magnetic Dance: The varying appearance of auroras in different hemispheres is attributed, in part, to the intricate interplay between the sun’s magnetic field and Earth’s magnetic field.