#osirisrex

It’s International Asteroid Day, and today we’re talking about everything asteroids! Although there are no known threats for the next 100 years, our Planetary Defense experts are constantly finding, tracking, and monitoring near-Earth objects to protect our home planet.

Asteroids are rocky remnants from the beginning of our solar system, and as of today, 26,110 near-Earth asteroids have been discovered!

So how do we spot these near-Earth objects? Let’s watch and see:

In addition to tracking and monitoring asteroids, we are also launching several missions to study these rocky relics. By studying asteroids, we can better understand the formation of our solar system. Here are some exciting missions you can look forward to:

OSIRIS-REx: Returning a Sample from Asteroid Bennu

Last year, our OSIRIS-REx mission successfully captured a sample of asteroid Bennu, a 4.5-billion-year-old asteroid the size of the empire state building.

Currently, OSISRIS-REx is making its long journey home carrying this sample as it returns to Earth in 2023.

Psyche: A Journey to a Metal World

Our Psyche mission will journey to a unique metal asteroid orbiting the Sun between Jupiter and Mars.

What makes the asteroid Psyche unique is that it appears to be the exposed nickel-iron core of an early planet, one of the building blocks of our solar system. Deep within rocky, terrestrial planets - including Earth - scientists infer the presence of metallic cores, but these lie unreachably far below the planets' rocky mantles and crusts. Because we cannot see or measure Earth's core directly, Psyche offers a unique window into the violent history of collisions and accretion that created terrestrial planets.

Lucy: Studying the Trojan Asteroids

Launching this year, our Lucy mission will be the first mission to study the Trojans, a group of asteroids that share Jupiter’s orbit around the Sun. Time capsules from the birth of our Solar System more than 4 billion years ago, the swarms of Trojan asteroids associated with Jupiter are thought to be remnants of the primordial material that formed the outer planets.

The mission takes its name from the fossilized human ancestor (called “Lucy” by her discoverers) whose skeleton provided unique insight into humanity's evolution. Likewise, the Lucy mission will revolutionize our knowledge of planetary origins and the formation of the solar system.

DART: Double Asteroid Redirection Test

Launching this year, our DART mission is a planetary defense driven test of technologies and will be the first demonstration of a technique to change the motion of an asteroid in space.

The destination of this mission is the small asteroid Dimorphos, which orbits slowly around its larger companion Didymos. Dimorphos is referred to as a moonlet since it orbits a larger asteroid.

The DART spacecraft will achieve the kinetic impact deflection by deliberately crashing itself into the moonlet. The collision will change the speed of the moonlet in its orbit around the main body by a fraction of one percent, but this will change the orbital period of the moonlet by several minutes - enough to be observed and measured using telescopes on Earth.

At NASA, every day is asteroid day, as we have missions exploring these time capsules of our solar system and surveying the sky daily to find potential hazards. We, along with our partners are watching the skies 24/7/365, so rest assured! We're always looking up.

Close view of the asteroid Bennu by OSIRIS-REx space probe 👏👏 Latest news from this mission : https://www.fromspacewithlove.com/osiris-rex-bennu/

A long way from Earth, looking back at home.

NASA’s OSIRIS-REx mission, still on its outward journey from Earth to the asteroid Bennu, took an image of the Earth system January 17 while undergoing engineering tests.

The spacecraft’s NAVCAM-1 instrument, part of a suit of imaging cameras used to orient the probe in space, captured Earth, its moon, and surrounding constellations from a distance of 39.5 million miles (63.6 million km).

Multiple stars are visible including the Pleiades star cluster of the Tarus constellation in the upper left, the star Hamal in the constellation Aries in the upper right, and the head of Cetus the Whale, centered around Earth.

OSIRIS-REx was speeding away from the Earth system at a speed of 19,000 miles per hour when it took the image. After traveling for nearly two years, the spacecraft will begin its approach to the asteroid Bennu in August, 2018, and will enter orbit December 8.

New Photo Shows the Moon May Be Farther Away Than You Think

If the Earth were the size of a basketball, the moon would be a tennis ball some 24 feet away. Because of space considerations, illustrations almost always put them much closer together than they actually are.

Our solar system is littered with asteroids and comets, and sometimes they get a little close to Earth. But no need to worry! This happens all the time. When an asteroid or comet could come close to our planet, it’s known as a near-Earth object – aka NEO.

But how close is “close”?

A near-Earth object is defined as an object that could pass by our Earth within 30 million miles. We begin to keep close watch on objects that could pass within 5 million miles of our planet.

To put that into perspective, our Moon is only 238,900 miles away.

However unlikely an impact is, we want to know about all near-Earth objects. Our Planetary Defense Coordination Office maintains watch for asteroids and comets coming close to Earth. Along with our partners, we discover, catalog and characterize these bodies.

But what if one of these objects posed a threat?

We want to be prepared. That is why we are working on several deflection techniques and technologies to help protect our planet.

So next time that you hear of an asteroid passing “close” to Earth, know that it’s just one of many that we are tracking.

Here are 10 more things you should know about Planetary Defense.

On October 20th, our OSIRIS-REx mission will make its first attempt to collect and retrieve a sample of asteroid Bennu, a near-Earth asteroid. On sample collection day, Bennu will be over 200 million miles away from Earth.  

Asteroids are the building blocks of our solar system. A sample of this ancient material can tell us about the history of our planet and the origins of life. Science results published from the mission on October 8th confirm that Bennu contains carbon in a form often found in biology or in compounds associated with biology.

To collect a sample, OSIRIS-REx will attempt a method NASA has never used before – called Touch-And-Go (TAG).  First, the spacecraft extends its robotic sampling arm, the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) – from its folded storage position. The spacecraft’s two solar panels then move into a “Y-wing” configuration over the spacecraft’s body, which positions them safely up and away from the asteroid’s surface during touch down. This configuration also places the spacecraft’s center of gravity directly over the TAGSAM collector head, which is the only part of the spacecraft that will contact Bennu’s surface.

Finding a safe sample collection site on Bennu’s rocky landscape was a challenge. During the sampling event, the spacecraft, which is the size of a large van, will attempt to touch down in an area that is only the size of a few parking spaces, and just a few steps away from enormous boulders.

The spacecraft will only make contact with Bennu for a matter of seconds - just long enough to blow nitrogen gas onto the surface to roil up dust and small pebbles, which will then be captured for a return to Earth.

We need to conduct a few tests before we can confirm we collected a large enough sample (about 2 oz). First, OSIRIS-REx will take images of the collector head to see if it contains rocks and dust. Second, the spacecraft will spin with the TAGSAM extended to determine the mass of collected material. If these measures show a successful collection, we will stow the sample for return to Earth. If sufficient sample has not been collected, the spacecraft has onboard nitrogen charges for two more attempts. The next TAG attempt would be made no earlier than January 2021.

Despite the many challenges, the OSIRIS-REx team is ready. They’ve practiced and prepared for this moment.

Join in with #ToBennuAndBack and tune in on October 20th.

Learn more about the OSIRIS-REx countdown to TAG HERE.

Learn more about the OSIRIS-REx mission HERE, or follow the mission on Facebook, Twitter and Instagram.