How two NASA missions will rewrite what we know about our solar system

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An asteroid located in the main belt between Mars and Jupiter and an object of the Kuiper belt located four billion kilometers will see their mysteries unveiled when NASA missions will explore in December and January.

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An asteroid located in the main belt between Mars and Jupiter and an object of the Kuiper belt located four billion kilometers will see their mysteries unveiled when NASA missions will explore in December and January.

Wednesday, November 7, NASA representatives Origins, spectral interpretation, identification of resources, explorer of safety regoliths (OSIRIS-REx) mission to return samples to the asteroid Bennu and his New Horizons mission to Pluto and the Kuiper Belt discussed the upcoming encounters of their spaceship with two worlds of very different solar systems at a NASA Scientific chat entitled "Small worlds, great discoveries. "

The debate was moderated by Dwayne Brown, NASA Office of Communications.

OSIRIS-REx Melissa Morris, assistant program scientist at NASA's headquarters, said the mission's space shuttle would come into orbit around Bennu on 3 December. She will map and study the asteroid to select a landing site. Hopefully, a rock sample of the landing site will be taken in July 2020 and returned to Earth for analysis in September 2023.

Hal Weaver of the Laboratory of Applied Physics, Johns Hopkins University(JHUAPL) New Horizons The project scientist pointed out that the second target of the mission after flying over Pluto in 2015 will be the farthest object ever visited by a spacecraft.

New Horizons will fly three times closer to its second target, Ultimate Thule, than to Kuiper Belt, and will make its closest approach at 00:33 EST on January 1, 2019.

In a pre-recorded message, Thomas Z., Associate Administrator of NASA Direction of the scientific missionand Lori Glaze, NASA Direction of the scientific mission Director of Planetary Sciences, listed five reasons to explore Bennu and Ultima Thule. First, studying the compositions, orbits and physical properties of small objects of this type will help scientists to understand not only these objects, but also the origin of the Sun, Earth, Moon, planets, asteroids and comets.

Second, understanding the distribution of organic molecules, water and other volatile compounds on these worlds can inform scientists about the formation of these materials, essential to life, in space. Organic materials are complex carbon molecules that are not life, but contain the precursors of life.

Third, the small worlds provide a window into the physical properties that continue to shape our solar system today. Fourth, it is essential to determine the orbits and physical characteristics of objects that can impact the Earth to understand the consequences of such an impact. Fifth, small worlds can host mineral resources that human space explorers might find useful in future missions of the outer solar system.

Both spaceships are equipped with cameras to photograph the observed worlds. OSIRIS-REx 'The camera suite has already captured an image of the rotating asteroid. New Horizons has both black and white and color cameras.

After arriving at Bennu, OSIRIS-REx Will begin the "Asteroid Operations" phase of his mission, which will include several asteroid flyovers, and begin two years of extensive studies of it, Morris said. The sample return capsule that will carry the samples home was built with proven technology and is not likely to lose materials en route, she added.

"Bennu is an asteroid without any atmosphere in the intense radiation of space", which means that it is very unlikely that life has survived. she explained. The main purpose of sample safety is to ensure that scientists do not inadvertently contaminate them with microbes from the Earth after returning samples.

Ultima Thule is a type of Kuiper belt object completely different from that of Pluto because it is composed of immaculate materials that have not changed since the formation of the solar system there are four billion years ago. ; years.

Carey Liss of JHUAPL, New Horizons As a planetary scientist, each star system has its own Kuiper belt. New Horizons is the first mission to visit such a belt. The Kuiper belts are located on the periphery of their systems, where there was not enough material to make giant planets.

Like KBOs, asteroids can be composed of primitive materials from the early solar system. Some are just remnants of materials that never form planets, while others are the result of collisions between larger asteroids. Bennu was probably formed by such a collision, while Ultima Thule has never been disturbed by an object and has remained the same since his formation.

A very dark object, Bennu only reflects three percent of the light it receives from the sun. This could mean that it is covered with carbon and organic matter, the building blocks of life. Scientists are trying to understand how these building blocks were common in the early solar system, explained OSIRIS-REx Amy Simon, global scientist, NASA Goddard Space Flight Center.

The main difference between the asteroids of the internal solar system and the KBOs of the external solar system lies in the fact that the latter consist mainly of ice and have ice in water, unlike the former. In the external solar system, water ice is as strong as rock and can build mountains.

"Ultima Thule never melted, never differentiated, never formed a nucleus, nor did our planet" and unlike many asteroids, Liss said.

OSIRIS-REx is the biggest mission back sample since Apollo and NASA's first mission to return samples of asteroids, Morris said. "We are very happy to bring back these samples, and many of these samples will be prepared for future generations of scientists.

Ultima Thule will remain a mystery until the day before the closest approach. Scientists think that it can be a binary system composed of two objects, possibly a binary contact in which two objects in orbit are close enough to touch each other. The KBO can also have moons.

contrary to OSIRIS-REx, New Horizons will not come into orbit around Ultima Thule, so it will only have a chance to collect data. "It's the frontier of planetary science," Weaver said.

New Horizons will fly by Ultima Thule at a speed of 32,000 miles per hour. OSIRIS-REx, on the other hand, will perform maneuvers that will slow it from 1100 miles per hour to one mile per hour to match Bennu's orbit. Communication signals will take a little over six minutes each way between OSIRIS-REx and the Earth and 12 hours and eight minutes in each direction between New Horizons and the Earth during encounters.

Tagged: Bennu New Horizons OSIRIS-REx The Ultima Thule range