OSIRIS-REx Launches This Week!

This Thursday, September 8, OSIRIS-REx, the asteroid sample return mission, launches into space! The spacecraft will map asteroid Bennu, and then return a sample to Earth. You can watch the launch online on NASA TV. Live coverage begins at 6:05 PM CDT.

Artist's depiction of OSIRIS-REx at asteroid Bennu. Image Credit 

I'll admit, this mission didn't sound super exciting to me at first glace. We've sent spacecrafts to survey asteroids before. However, as soon as I started reading about the ambitious plan to take a sample from the surface of the asteroid and return it to Earth, I got pretty excited. 

OSIRIS-REx assembled. Image Credit 

After OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) launches, it will enter orbit around the Sun. In 2017 it will fly by Earth to steal a little momentum, speeding up and changing its orbital inclination, putting it on path to Bennu. The spacecraft will begin approaching Bennu in August of 2018, falling into a synchronous orbit. For nearly a year it will survey Bennu, creating a detailed map of its surface and analyzing its chemical composition.

The asteroid Vesta was completely mapped by the Dawn mission, which is currently exploring the dwarf planet Ceres. Image Credit 

The real excitement of the mission will begin in July 2019, when the spacecraft will make subtle orbital changes to get closer to Bennu. An arm will extend from the spacecraft and make contact with the asteroid for 5 seconds. (Mission planners call this a "gentle high-five"). The arm will release a burst of nitrogen gas, causing loose rocks and surface soil to fly up. Some of this will be collected on the sampler head. It has enough nitrogen for three attempts. OSIRIS-REx has the ability to collect anywhere from 2 ounces to 4 pounds of material. After collecting the material, the arm will retract, and the collector head with the sample will be stowed in a compartment on the spacecraft. 

Testing the arm. Image Credit

When Bennu and OSIRIS-REx are in a good spot in their orbit for the spacecraft to return to Earth (sometime in 2021) OSIRIS-REx will leave Bennu and begin the journey home. It should get back to Earth in September 2023. The little sample return capsule will detach from the spacecraft. It has a strong heat shield, so will free fall through Earth's atmosphere. About 2 miles from the surface it will deploy a parachute, and land in the Utah desert. Check out this fantastic mission timeline for more details! 

The capsule from the Stardust mission that returned samples of a comet's tail. Image Credit 

In clean labs, scientists will analyze the sample's chemical components, helping us understand the earliest stages of the Solar System's formation. Scientists are particularly interested in looking for amino acids and sugars, the building blocks for life. If they exist on some of the oldest pieces of our Solar System, it could indicate that the early Solar System was rich with the stuff needed for life to evolve. 

OSIRIS-REx ready to go at the launch pad. Image Source

Bennu is also a potentially hazardous asteroid. It has a relatively high probability (still only a 0.07% chance) of impacting the Earth late in the 22nd century. This mission will determine the asteroid's physical and chemical properties, which will help future scientists know how to deflect the asteroid if necessary. 

OSIRIS-REx is a great example of how science is a long game. This mission took years of planning and testing, and then will take over seven years to complete! Now that you know about the mission, you can follow along with it from beginning to end. Follow the mission at its website, on Facebook, or Twitter. You can always learn what's happening with space exploration at the Dome Planetarium at the Peoria Riverfront Museum.  Follow us on Facebook or Twitter for daily updates! 

Have dinner with an astronaut! Registration closes at 4 PM on September 5. Buy tickets here