American Space agency NASA has predicted that the asteroid ‘2001 FO32’ is the largest to pass by Earth in 2021. It will be at its closest on 21st March.

  • NASA will provide a rare opportunity for astronomers to get a good look at a rocky relic that formed at the dawn of our solar system.
  • 2001 FO32 Asteroid
    • Discovery: It was discovered 2 decades ago and ever since the scientists have been tracking its orbital path around the Sun very accurately.
      • It was discovered in March 2001 by the Lincoln Near-Earth Asteroid Research program in Socorro, New Mexico.
      • 1998 OR2 was the last notably large asteroid that passed close to earth on 29th April, 2020. While 2001 FO32 is somewhat smaller than 1998 OR2, it will be 3-times nearer to Earth.
    • Orbit: It is in a highly eccentric orbit around the Sun. It completes one orbit every 810 days. The orbit is tilted 39° to Earth’s orbital plane.
      • This orbit takes the asteroid closer to the Sun than Mercury, and twice as far from Sun as Mars.
    • Speed: The asteroid will pass by at about 124,000 kph. It is faster than the speed at which most asteroids encounter Earth.
      • The reason for the asteroid’s unusual speed is its close approach to the earth.
    • No Threat of Collision
      • This will make its closest approach at a distance of about 2 million km or 5 1/4 times the distance from Earth to the Moon.
        • The distance is close in astronomical terms, that’s why it has been designated a “potentially hazardous asteroid”.
        • There is no threat of a collision with our planet now or for centuries to come.
    • Next Close Approach: 2001 FO32 asteroid will not come this close to Earth again until 2052, when it will pass by at about seven lunar distances, or 2.8 million km.
  • Significance
    • The asteroid will provide an opportunity for astronomers to get a more precise understanding of the asteroid’s size and albedo (i.e. how bright, or reflective, its surface is), and a rough idea of its composition.
    • When sunlight hits an asteroid’s surface, minerals in the rock absorb some wavelengths while reflecting others. By studying the spectrum of light reflecting off the surface, astronomers can measure the chemical “fingerprints” of the minerals on the surface of the asteroid.
  • Other Recent Asteroids Seen in News:
    • Asteroid 2020 ND
    • 163348 (2002 NN4)
    • Asteroid 16 Psyche
    • Asteroid 2018VP1
    • Asteroid Bennu


  • It orbit the Sun and are small bodies in the solar system.
  • They are made up of metals and rocks.
  • They tend to have shorter and elliptical orbits.
  • They do not produce a coma or tail atmosphere.
  • The asteroid belt is a torus-shaped region in the Solar System, located roughly between the orbits of the planets Jupiter and Mars.

Classification of Asteroids

  • Main Asteroid Belt: The majority of known asteroids orbit within the asteroid belt between Red Planet and Jupiter.
  • Trojans: These asteroids share an orbit with a larger planet, but do not collide with it because they gather around two special places in the orbit (called the L4 and L5 Lagrangian points). There, the gravitational pull from the sun and the planet are balanced.
    • Lagrange Points are positions in space where the gravitational forces of a two body system like Sun and Planet Earth produce enhanced regions of attraction and repulsion. These can be used by spacecraft to reduce fuel consumption needed to remain in position.
  • Near-Earth Asteroids: These objects have orbits that pass close by that of Earth. Asteroids that actually cross Earth’s orbital path are known as Earth-crossers.

Potentially Hazardous Asteroid

  • The Potentially Hazardous Asteroid means that an asteroid has the potential to make threatening close approaches to the Earth.
  • Specifically, all asteroids with a Minimum Orbit Intersection Distance of 0.05 AU (which is about 7,480,000 Kilometer) or less and an Absolute Magnitude (H) of 22.0 (about 150 mt in diameter) or less are considered PHAs.
    • Minimum Orbit Intersection Distance is a method for calculating the minimum distance between two almost overlapping elliptical orbits.
    • The Astronomical Unit is the distance between the Earth and the Sun and is roughly 150 million kilometer.
    • The absolute magnitude is a measure of the star’s luminosity i.e. the total amount of energy radiated by the star every second.

Largest Asteroid 2001 FO32 to pass by Earth in March Largest Asteroid 2001 FO32 to pass by Earth in March