Space Apps Challenge 2018

Asteroid Bennu has a roughly spheroidal shape, which resembles a spinning top. The direction of rotation about its axis is retrograde with respect to its orbit. Bennu has a fairly smooth shape with one prominent 10–20 m boulder on its surface, in the south

The origin of the carbonaceous material that composes asteroid bennu came from dying stars such as red giants and supernovae. According to the accretion theory, this material came together 4.5 billion years agone throughout the formation of the Solar System. Asteroid Bennu's basic mineralogy and chemical nature would have been established throughout the primary ten million years of the Solar System's formation, where the carbonaceous material underwent some geologic heating and chemical transformation into a lot of advanced minerals. Bennu probably began in the asteroid belt as a fraction from a bigger body with a diameter of a 100 km. Simulations suggest a 70% chance it came from the Polana family and a 30% chance it derived from the Eulalia family.

Bennu has a shape that looks a bit like a spinning top. It is roughly 500 meters (1,640 feet) in diameter and orbits the sun once every 1.2 years, or 436.604 days.Every six years or so, it comes very close to Earth.

Source: www.space.com

1. Asteroid Bennu has a roughly spheroidal shape, which resembles a spinning top. The direction of rotation about its axis is retrograde with respect to its orbit. Bennu has a fairly smooth shape with one prominent 10–20 m boulder on its surface, in the southern hemisphere.^[14]There is a well-defined ridge along the equator of asteroid Bennu. The presence of this ridge suggests that fine-grained regolith particles have accumulated in this area, possibly because of its low gravity and fast rotation.^[14]

Bennu is a leftover fragment from the tumultuous formation of the solar system. Some of the mineral fragments inside Bennu could be older than the solar system. These microscopic grains of dust could be the same ones that spewed from dying stars and eventually coalesced to make the Sun and its planets nearly 4.6 billion years ago. But pieces of asteroids, called meteorites, have been falling to Earth's surface since the planet formed. So why don't scientists just study those old space rocks? Because astronomers can't tell (with very few exceptions) what kind of objects these meteorites came from, which is important context. Furthermore, these stones, that survive the violent, fiery decent to our planet's surface, get contaminated when they land in the dirt, sand, or snow. Some even get hammered by the elements, like rain and snow, for hundreds or thousands of years. Such events change the chemistry of meteorites, obscuring their ancient records.

The OSIRIS-REx is a NASA asteroid study and sample-return mission. Launched on 8 September 2016, its mission is to study asteroid 101955 Bennu, a carbonaceous asteroid, and return a sample to Earth on 24 September 2023 for detailed analysis.

Source: Wikipedia

It's close to Earth

1. Unlike most other asteroids that circle the Sun in the asteroid belt between Mars and Jupiter, Bennu’s orbit is close in proximity to Earth's, even crossing it. The asteroid makes its closest approach to Earth every 6 years. It also circles the Sun nearly in the same plane as Earth, which made it somewhat easier to achieve the high-energy task of launching the spacecraft out of Earth's plane and into Bennu's. Still, the launch required considerable power, so OSIRIS-REx used Earth’s gravity to boost itself into Bennu’s orbital plane when it passed our planet in September 2017.

(retrieved from Nasa Website)