IAS Gyan

Daily News Analysis


27th December, 2023 Science and Technology


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  • In an extension of its celestial duties, the spacecraft that delivered asteroid samples from Bennu, OSIRIS-REx has embarked on a new mission, and Nasa has renamed it.
  • The mission will now be called OSIRIS-APEX as it heads to study the near-Earth asteroid Apophis.


  • Apophis is expected to have a close flyby of Earth in 2029, a phenomenon not witnessed in recorded history.
  • Its close approach in 2029 will bring it within 20,000 miles of Earth, closer than some satellites and potentially visible in the Eastern Hemisphere.
  • OSIRIS-APEX's mission aims to take advantage of this significant celestial event for scientific study.
  • OSIRIS-REx previously achieved fame by successfully returning a sample from asteroid Bennu to Earth on September 24.
  • Despite completing this mission, the spacecraft retained adequate fuel and fully functional instruments.

Objectives of OSIRIS-APEX

  • The repurposed mission seeks to rendezvous with Apophis in April 2029.
  • It aims to study the changes induced by Earth's gravitational pull during Apophis' close flyby, analyzing alterations in orbit, rotation, and surface features.
  • Studying Apophis during its close Earth approach provides insights into planetary formation and seismic activities on asteroids.
  • Findings from this mission might contribute to enhanced planetary defense strategies.

Asteroid Apophis

  • Apophis, known as 99942 Apophis, is a near-Earth asteroid and one of the most significant objects studied in the context of potential impacts with Earth.
  • Discovered in 2004, Apophis caused initial concerns due to its close approach trajectory to Earth and its considerable size.

Physical Characteristics:

  • Apophis measures approximately 340 meters (1,115 feet) in diameter.
  • Apophis is categorized as a stony "S-type" asteroid, distinct from the carbon-rich "C-type" Bennu, composed mainly of silicate materials and nickel-iron.

Discovery and Naming:

  • Discovered in June 2004 by astronomers at the Kitt Peak National Observatory in Arizona.
  • Named after the ancient Egyptian god Apep (also known as Apophis), associated with chaos and destruction.


The OSIRIS-APEX mission represents a scientific endeavor to capitalize on the rare celestial event of Apophis' close flyby, aiming to delve deeper into the study of asteroids and their potential implications for planetary understanding and defense strategies.




Q. What is the primary scientific objective of the OSIRIS-APEX mission concerning asteroid Apophis?

A) Analyzing the asteroid's chemical composition through remote spectroscopy

B) Collecting and returning surface samples of Apophis to Earth

C) Monitoring Apophis' seismic activity during its close approach to Earth

D) Investigating the effects of Earth's gravitational pull on Apophis' orbit and surface features

Answer: D)