Context:
Recent research indicates that a gamma-ray burst (GRB) triggered by a supernova explosion in a galaxy nearly two billion light-years away has caused a significant disruption in the ionosphere of Earth.
Relevance:
GS III: Science and Technology
Dimensions of the Article:
- Key Findings from the Research on Gamma-Ray Burst
- Gamma-Ray Bursts: A Brief Overview
- Ionosphere
Key Findings from the Research on Gamma-Ray Burst
Supernova Explosion and Gamma-Ray Release
- Temporal Context:
- Approximately two billion years ago, a supernova explosion occurred in a distant galaxy outside the Milky Way.
- The explosion unleashed a substantial surge of gamma rays into the cosmos.
- Journey to Earth:
- Over the span of two billion years, the gamma rays traveled through space, reaching Earth in 2022.
Utilization of China Seismo-Electromagnetic Satellite (CSES)
- Observational Tool:
- The effects of the gamma-ray burst were examined using the China Seismo-Electromagnetic Satellite (CSES), also known as Zhangheng.
- Launched in 2018, the satellite carried the Electric Field Detector (EFD) instrument, offering unprecedented resolution for analysis.
Impact on Earth’s Ionosphere
- Ionosphere Disturbance:
- The gamma-ray burst induced a remarkable disruption in Earth’s ionosphere.
- The ionosphere, situated 30-600 miles above the planet’s surface, exhibited significant variations.
- Detection Timeframe:
- The disturbance was detected in October 2022.
Multi-Satellite Observations
- Collaborative Monitoring:
- The European Space Agency’s Integral and various satellites in proximity to Earth recorded the impact.
- Observations revealed a strong variation in the electric field of the ionosphere.
Duration and Aftereffects
- Gamma Ray Persistence:
- The gamma rays lingered for approximately 13 minutes.
- Extended Impact Period:
- Despite the short duration of the gamma rays, the disturbance in the ionosphere persisted for several hours.
- Global Effects:
- The impact even triggered lightning detectors in India.
Record-Breaking Potency
- Unprecedented Potency:
- Scientists identified this gamma-ray burst as the most potent ever recorded.
Gamma-Ray Bursts: A Brief Overview
Definition and Characteristics
- Nature of Gamma-Ray Bursts:
- Gamma-ray bursts (GRBs) are brief explosions of gamma rays, representing the most energetic form of light.
- Duration and Brightness:
- Lasting from milliseconds to hours, GRBs shine hundreds of times brighter than typical supernovae.
- They are about a million trillion times as bright as the Sun.
- Observational Location:
- Observed in distant galaxies, GRBs are the brightest electromagnetic events known in the universe.
Classification of Gamma-Ray Bursts
- Long- and Short-Duration Events:
- Astronomers categorize GRBs into long- and short-duration events.
- Long-duration bursts, associated with massive star deaths in supernovae, last from 2 seconds to several hours.
- Short-duration bursts, lasting less than 2 seconds, result from events like the merger of neutron stars or a neutron star with a black hole.
- Common Outcome:
- Regardless of type, both long and short-duration events lead to the creation of a new black hole.
Ionosphere:
- Geographical Location:
- The ionosphere is situated in Earth’s upper atmosphere, spanning an altitude of approximately 30 to 600 miles (50 to 950 kilometers) above the Earth’s surface.
- Ionization Process:
- Ionized by solar radiation, the ionosphere forms a layer of charged particles.
- Dynamic Sensitivity:
- Highly sensitive to changing magnetic and electrical conditions in space, often influenced by solar activity.
- Expands and contracts in response to solar radiation.
Significance of the Ionosphere
- Radio Propagation:
- Influences the propagation of radio waves, reflecting and refracting them back to Earth.
- Enables long-distance communication through radio transmissions.
- Solar Radiation Shield:
- Acts as a protective shield against harmful solar radiation, particularly extreme ultraviolet rays from the sun.
- Auroras Formation:
- Interactions between charged particles in the ionosphere and Earth’s magnetic field result in phenomena like auroras.
- Auroras are luminous displays predominantly seen at high latitudes.
-Source: Indian Express
