The National Aeronautics and Space Administration’s (NASA) OSIRIS-REx spacecraft has recently made headlines after it successfully touched down on the surface of asteroid Bennu. The aim of this daring move was to collect a sample of rock and dust from the asteroid’s surface.
OSIRIS-REx Mission Overview
Launched in 2016, the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) spacecraft embarked on the United States’ first-ever mission to collect and return an unaltered, pristine sample from an asteroid for the purpose of scientific study. This seven-year voyage is set to end in 2023 when the spacecraft will bring back at least 60 grams of samples to Earth.
NASA anticipates that the mission will mark the largest quantity of extraterrestrial material returned to Earth since the Apollo missions, the NASA program acknowledged for enabling American astronauts to set foot on the moon from 1968-72. The spacecraft is equipped with five instruments such as cameras, a spectrometer, and a laser altimeter. These are designed to facilitate detailed exploration of Bennu.
Using a robotic arm known as the Touch-And-Go Sample Acquisition Mechanism (TAGSAM), the spacecraft recently “TAGged” the asteroid successfully at a sample site and gathered a sample. Following the collection of the sample, the spacecraft will begin its departure process in 2021. Subsequently, it will embark on the over two-years-long journey back to Earth.
The Ancient Asteroid: Bennu
Bennu, an ancient asteroid located over 200 million miles away from Earth, offers scientists a glimpse into the early solar system as it existed billions of years ago. Bennu has remained largely unaltered since its formation, housing rocks and chemicals dating back to the genesis of the solar system.
The asteroid is a B-type, signifying that it contains substantial quantities of carbon and other minerals. Its high carbon content results in its low reflectivity, reflecting only about 4% of light that strikes it, as compared to 30% from Earth and 65% from Venus.
According to NASA’s high-resolution images, Bennu’s surface is peppered with massive boulders, which posed a challenge during the sample collection process. Bennu, a Near Earth Object, might pose a threat to Earth between the years 2175 and 2199 due to the slight possibility of it colliding with our planet. Lincoln Near-Earth Asteroid Research team, funded by NASA, discovered Bennu in 1999.
About Asteroids
Asteroids, also known as minor planets, are rocky objects that orbit the Sun. Currently, there are 994,383 known asteroids that are remnants of the formation of the solar system over 4.6 billion years ago. These asteroids fall into three categories: those found in the main asteroid belt between Mars and Jupiter, trojans, and Near-Earth Asteroids (NEAs).
The largest group of asteroids, numbering between 1.1-1.9 million, reside in the main asteroid belt. Trojans share an orbit with a larger planet, such as Jupiter, Neptune, and Mars. NEAs, which include more than 10,000 known asteroids that cross the Earth’s orbit, are categorized based on their potential to make threatening close approaches to Earth. More than 1,400 of them are labeled as potentially hazardous asteroids (PHAs).
Last Modified: February 9, 2024