NASA to Launch Mission to Asteroid in 2016 -- Seeking Organic Molecules that may have Seeded Life on Earth.
NASA has selected the University of Arizona to lead a sample-return mission to an asteroid. The team is led by Michael Drake, director of the the UA's Lunar and Planetary Laboratory. OSIRIS-REx will rendezvous with asteroid 1999 RQ36, extend a sample collecting device and return at least 60 grams (a little over 2 ounces) of pristine material to Earth for analysis.
"It will return samples of pristine organic material that scientists think might have seeded the sterile early Earth with the building blocks that led to life. Such samples do not currently exist on Earth. OSIRIS-REx will also provide the knowledge that will guide humanity in deflecting any future asteroid that could collide with Earth, allowing humanity to avoid the fate of the dinosaurs."
OSIRIS-REx will spend longer than a year exploring 1999 RQ36 before acquiring samples that will provide geologic context essential to expanding our understanding of the asteroid-comet continuum. The mission will provide near-live coverage of 1999 RQ36 operations and sample return to Earth. Samples will return to Earth in the year 2023.
The return to Earth of pristine samples with known geologic context will enable precise analyses that cannot be duplicated by spacecraft-based instruments. Pristine carbonaceous materials have never before been analyzed in laboratories on Earth.
Extensive characterization by the Arecibo Planetary Radar System, the Spitzer Space Telescope, and ground-based telescopes in Arizona and elsewhere have resulted in exceptional knowledge about the asteroid. 1999 RQ36 orbits the sun every 1.2 years, crossing the Earth's orbit every September. Its shape and rotation rate are well known, allowing OSIRIS-REx to make a safe, albeit short, touchdown.
"Our spacecraft will sneak up to RQ36 over the course of weeks," said Dante Lauretta, the mission's deputy principal investigator and an associate professor at the UA's Lunar and Planetary Laboratory. "For the first time in space-exploration history, a mission will travel to, and return pristine samples of a carbonaceous asteroid with known geologic context. Such samples are critical to understanding the origin of the solar system, Earth, and life. Once the two objects are traveling in sync, OSIRIS-REx will extend its sample collector, touch the surface for five seconds, collect well over 60 grams of sample, and get out of there."
Using an injection of ultra-pure nitrogen, the OSIRIS-REx sample-collecting device will stir up dirt and small gravel to be captured and sealed for return to Earth. The samples are returned to the surface of the Earth using hardware and procedures successfully demonstrated on the Stardust mission, which returned samples from comet Wild 2 in 2006.
"This is a critical step in meeting the objectives outlined by President Obama to extend our reach beyond low-Earth orbit and explore into deep space," said NASA Administrator Charlie Bolden. "It's robotic missions like these that will pave the way for future human space missions to an asteroid and other deep space destinations."
NASA selected OSIRIS-REx after reviewing three concept study reports for new scientific missions, which also included a sample return mission from the far side of the moon and a mission to the surface of Venus.
Asteroids are leftovers formed from the cloud of gas and dust -- the solar nebula -- that collapsed to form our sun and the planets about 4.5 billion years ago. As such, they contain the original material from the solar nebula, which can tell us about the conditions of our solar system's birth.
After traveling four years, OSIRIS-REx will approach the primitive, near Earth asteroid designated 1999 RQ36 in 2020. Once within three miles of the asteroid, the spacecraft will begin six months of comprehensive surface mapping.
The science team then will pick a location from where the spacecraft's arm will take a sample. The spacecraft gradually will move closer to the site, and the arm will extend to collect more than two ounces of material for return to Earth in 2023. The mission, excluding the launch vehicle, is expected to cost approximately $800 million.
The sample will be stored in a capsule that will land at Utah's Test and Training Range in 2023. The capsule's design will be similar to that used by NASA's Stardust spacecraft, which returned the world's first comet particles from comet Wild 2 in 2006. The OSIRIS-REx sample capsule will be taken to NASA's Johnson Space Center in Houston. The material will be removed and delivered to a dedicated research facility following stringent planetary protection protocol. Precise analysis will be performed that cannot be duplicated by spacecraft-based instruments.
RQ36 is approximately 1,900 feet in diameter or roughly the size of five football fields. The asteroid, little altered over time, is likely to represent a snapshot of our solar system's infancy. The asteroid also is likely rich in carbon, a key element in the organic molecules necessary for life. Organic molecules have been found in meteorite and comet samples, indicating some of life's ingredients can be created in space. Scientists want to see if they also are present on RQ36.
"This asteroid is a time capsule from the birth of our solar system and ushers in a new era of planetary exploration," said Jim Green, director, NASA's Planetary Science Division in Washington. "The knowledge from the mission also will help us to develop methods to better track the orbits of asteroids."
The mission will accurately measure the "Yarkovsky effect" for the first time. The effect is a small push caused by the sun on an asteroid, as it absorbs sunlight and re-emits that energy as heat. The small push adds up over time, but it is uneven due to an asteroid's shape, wobble, surface composition and rotation. For scientists to predict an Earth-approaching asteroid's path, they must understand how the effect will change its orbit. OSIRIS-REx will help refine RQ36's orbit to ascertain its trajectory and devise future strategies to mitigate possible Earth impacts from celestial objects.
This is the third mission in NASA's New Frontiers Program. The first, New Horizons, was launched in 2006. It will fly by the Pluto-Charon system in July 2015, then target another Kuiper Belt object for study. The second mission, Juno, will launch in August to become the first spacecraft to orbit Jupiter from pole to pole and study the giant planet's atmosphere and interior. NASA's Marshall Space Flight Center in Huntsville, Ala., manages New Frontiers for the agency's Science Mission Directorate in Washington.
The Daily Galaxy via NASA/GSFC/The University of Arizona