NASA is sending a space robot to run after an asteroid, but the question is why?

In a press conference in mid-August, Jim Green, director of NASA's Planetary Science Division said the mission is aimed to trace the origin of life.

According to Green, the U.S. spacecraft dubbed as OSIRIS-REx will be launched on Sept. 8 from Cape Canaveral Air Force Station in Florida. Its task is to chase down the asteroid named Bennu, scoop out samples of it and bring it to earth by dropping of the capsule holding the asteroid sample by September 2023.

Associated Press notes that it will take seven years to complete the sci-fi-like mission, the biggest and most ambitious mission since the Apollo moon rocks, in the late 1960s and early 1970s. OSIRIS-REx is expected to travel four billion miles through space.

"We are going out to explore an unknown world," said principal scientist Dante Lauretta of the University of Arizona at Tucson. "We're going to map it in great detail. It will be the most well characterized asteroid in our solar system by the time we're through with it."

Why Bennu?

NASA says Bennu is very interesting as it is highly potentially dangerous. Among the asteroids surrounding the solar system, Bennu became the top choice after astronomers studied its size, composition and proximity to Earth.

"Bennu is a B-type asteroid with a ~500 meter diameter. It completes an orbit around the Sun every 436.604 days (1.2 years) and every 6 years comes very close to Earth, within 0.002 AU. These close encounters give Bennu a high probability of impacting Earth in the late 22nd century. Bennu's size, primitive composition, and potentially hazardous orbit make it one of the most fascinating and accessible NEOs ... and the ideal OSIRIS-REx target asteroid," NASA said on their website dedicated to the mission.

What is OSIRIS-Rex Made of?

NASA's spacecraft OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security - Regolith Explorer) was built by Lauretta. Fact sheet about OSIRIS-Rex says it has a length of 20.25 feet (6.2 meters) with solar arrays deployed. It is powered by two solar panels that generate between 1,226 watts and 3,000 watts, depending on the spacecraft's distance from the sun.

To assure success and efficiency, the spacecraft is loaded with three cameras, a scanning LIDAR (Light Detection and Ranging), Thermal Emission Spectrometer (OTES), Visible and Infrared Spectrometer (OVIRS) and Regolith X-ray Imaging Spectrometer (REXIS).