- 99942 Apophis asteroid will flyby very close to earth on April 13, 2029.
- The asteroid will flyby at a distance of about 31000km above the surface of the earth.
- It is the first time that an asteroid of the size of about 340 m wide will flyby so close to earth.
- The asteroid is named after ancient Egypt’s ‘god of chaos’.
- Though the asteroid is expected to be harmless, optical and radar telescopes are deployed to study various features important like its size, shape, orbit, composition and possibly even its interior
- Asteroid’s orbit
- Since the asteroid will pass through so close, earth’s gravity will have an effect on the asteroid’s orbit.
- Spin of the asteroid
- The earth’s gravity will also affect the spin of the asteroid.
- The change in spin produces avalanches on asteroid which can reveal details on interior of the asteroid.
- Defense for asteroid collision
- Studying the orbital behavior of such closely approaching asteroids can help to understand potential solution to ward off threats from similar Potentially Hazardous Asteroids.
- Note: NASA’s HAMMER Mission is one such effort to ward off threat from closely approaching asteroids.
(HAMMER – Hypervelocity Asteroid Mitigation Mission for Emergency Response vehicle.)
In brief: Asteroids
- Asteroids are rocky objects within the orbit of Jupiter, most of which orbit the sun in the same direction as the planets. Asteroids are also called minor planets.
- The largest asteroid, Ceres, has a diameter of about 900 km, followed by Vesta which is about 500 km in diameter.
- Asteroids orbit the Sun at distances of 2 to 3.5 AU (1 Astronomical Unit = 150 million kilometers, distance between earth and sun).
- This region of the solar system between the orbits of Mars and Jupiter is called the asteroid belt.
- The early solar system is thought to have been filled with planetesimals, most of which were incorporated into the planets.
- The leftover objects that missed out on becoming a planet make up the present-day asteroids.