NASA has launched a spacecraft named OSIRIS-APEx, formerly known as OSIRIS-REx, to study the asteroid Apophis. This comes after OSIRIS-REx successfully completed a seven-year journey to bring a sample of the Bennu asteroid back to Earth.
“The former OSIRIS-REx spacecraft sets off on a seven-year, 4 billion-mile journey to study asteroid Apophis and take advantage of the asteroid’s 2029 flyby of Earth, the likes of which hasn’t happened since the dawn of recorded history,” stated NASA in a December 22 announcement.
Apophis, measuring about 1,100 feet in width, is anticipated to have a safe passage close to Earth on April 13, 2029, coming within 19,794 miles of the planet’s surface. This will mark the closest approach by an asteroid of this size that scientists have known about in advance.
“The intrigue of Apophis is its exceptionally close approach of our planet (Earth) on April 13, 2029,” said NASA. However, it is important to note that Apophis will not collide with Earth during this encounter.
The 2029 pass will bring Apophis within 20,000 miles of Earth’s surface, closer than some satellites and potentially visible to the naked eye in the Eastern Hemisphere. NASA views this close approach as a valuable natural experiment.
Dani Mendoza DellaGiustina, principal investigator for OSIRIS-APEX, highlighted the significance of Apophis’ close encounter, stating that it is a great natural experiment. The close approach is expected to alter the asteroid’s orbit and the length of its 30.6-hour day, potentially causing quakes and landslides that could reveal what lies beneath the surface.
“OSIRIS-APEX will study Apophis immediately after such a pass, allowing us to see how its surface changes by interacting with Earth’s gravity,” explained Amy Simon, the mission’s project scientist based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
Apophis, named after the ancient Egyptian demon serpent symbolizing evil and chaos, is also referred to as the ‘God of Chaos.’ This near-Earth object (NEO) measures about 1,100 feet across and is composed of silicate materials and nickel-iron, distinguishing it from the carbon-rich Bennu.
NASA notes that Apophis originated in the main asteroid belt between Mars and Jupiter. Over millions of years, its orbit was altered by the gravitational influence of large planets like Jupiter, causing it to orbit the Sun closer to Earth. Consequently, Apophis is classified as a near-Earth asteroid rather than a main-belt asteroid.