What are asteroids? How real is the threat of them causing extinction of life? What strategies have been developed to prevent such a catastrophe?
What are asteroids? How real is the threat of them causing extinction of life? What strategies have been developed to prevent such a catastrophe?
Subject: Science & Technology
Asteroids are rocky, airless remnants left over from the Solar System’s formation ≈ 4.6 billion years ago. Ranging from meter-sized boulders to dwarf-planet–scale Ceres (≈940 km), most orbit in the main belt between Mars and Jupiter, though thousands follow Earth-crossing paths and are classified as near-Earth objects (NEOs)
Assessment of Extinction-Level Threats
- The discovery of 2,818 near-Earth asteroids in 2023 highlights the ongoing identification of potential threats.
- Asteroids larger than 1 kilometer can cause global catastrophes through:
- Impact winter causing prolonged darkness and cooling.
- Massive tsunamis and earthquakes.
- Release of harmful gases and debris into the atmosphere.
Planetary-defense strategies
Approach | Principle & status | Merits | Limitations |
---|---|---|---|
Early detection | Global surveys such as NASA’s NEO Observations Program, ESA’s Flyeye, LSST, and India’s NETRA track orbits years–decades in advance. | Buys time; low cost per life saved | Coverage gaps for small, faint objects |
Kinetic impactor | Hit the asteroid with a high-speed spacecraft to nudge its orbit; proven by NASA’s DART (2022), which shortened Dimorphos’ orbital period by 33 min. | Technology-ready; scalable for 50 m–500 m targets | Less effective on rubble-pile or very large bodies |
Gravity tractor | Station a massive spacecraft nearby; mutual gravity slowly drags the asteroid off course (concept tested in simulations). | Gentle, precise; preserves object intact | Requires years–decades of lead time |
Nuclear standoff blast | Detonate device near surface to vaporize material, creating a rocket-like plume that alters trajectory; modeled extensively, retained as last resort. | Works on large or short-warning threats | Political, legal, and debris-fragmentation risks |
Civil-defense planning | Evacuation drills, impact-forecast communication protocols under UN-backed International Asteroid Warning Network (IAWN). | Saves lives if deflection fails | Only mitigates, doesn’t prevent impact |
Continued investment in sky surveys, technology demonstration missions, and multinational response frameworks will convert a low-probability but high-consequence danger into a manageable natural hazard rather than an existential threat.
Answer Length
Model answers may exceed the word limit for better clarity and depth. Use them as a guide, but always frame your final answer within the exam’s prescribed limit.
In just 60 sec
Evaluate your handwritten answer
- Get detailed feedback
- Model Answer after evaluation
Crack UPSC with your
Personal AI Mentor
An AI-powered ecosystem to learn, practice, and evaluate with discipline
Start Now