Asteroid Bennu & its hidden mysteries

A momentous revelation marked the initial glimpse into the outcome of a seven-year endeavor, designed to retrieve fragments from an asteroid. NASA's Houston-based officials unveiled images portraying rock fragments resembling salt and pepper, as well as particles of celestial matter, dark as space itself, brought back from the asteroid Bennu. These findings were accompanied by the presentation of preliminary scientific insights derived from the material. The Osiris-Rex mission culminated in September, when a capsule containing the collected asteroid samples re-entered Earth's atmosphere, ultimately landing in the Utah desert.

Upon the careful examination of the external container, it was discovered that some of the material had inadvertently escaped. Scientists rapidly conducted an analysis, which offered initial revelations. Among these revelations, the presence of water-saturated clay minerals in the asteroid fragments was noted, carrying potential implications for our understanding of Earth's transformation into a water-rich planet. The theory posits that asteroids akin to Bennu may have collided with Earth, contributing to the formation of our oceans.

Dante Lauretta, a prominent figure in planetary sciences at the University of Arizona and the mission's principal investigator, expounded on the significance of these findings, suggesting that the arrival of clay minerals resembling those retrieved from Bennu played a pivotal role in shaping Earth's habitable conditions, including its bodies of water.

Additionally, the analyzed materials contained sulfur, a pivotal element facilitating geological changes in rocks and holding significance in biological processes. Furthermore, magnetite, an iron oxide mineral, was identified, with potential implications for catalyzing organic chemical reactions. Dr. Lauretta articulated the profound implication of these findings, highlighting their potential connection to the origins of life on Earth.

A further revelation pertains to the high carbon content within the asteroid fragments, a fundamental element in the foundational constituents of life. In one instance, a sample exhibited an impressive carbon content of 4.7 percent by weight. The recognition of these components led Daniel Glavin, a NASA astrobiologist, to express satisfaction with the mission's success and the quality of the samples obtained.

The Osiris-Rex mission, an abbreviation signifying Origins, Spectral Interpretation, Resource Identification, and Security, Regolith Explorer, concluded its remarkable journey on September 24 when the capsule, carrying the asteroid fragments, made its controlled descent beneath a parachute in the Utah wilderness. Subsequently, the capsule was transported to NASA's Johnson Space Center in Houston, where it was meticulously opened to reveal the cosmic material.

However, the serendipitous leakage of the celestial bounty posed an unexpected challenge. The substantial quantity of material exceeded initial expectations, necessitating meticulous retrieval to access the primary sample within the collection tool. This process, though time-consuming, has provided a captivating glimpse of the celestial treasures.

The precise volume of material remains undisclosed, pending further disassembly. Earlier estimations, derived from maneuvers executed while the spacecraft was still at Bennu, pointed to a rough estimate of 8.8 ounces, surpassing the mission's goal of at least 2.1 ounces of asteroid fragments.

The scientific community's anticipation is high as they look forward to comparing the Bennu samples with those retrieved by Japan's Hayabusa2 from the asteroid Ryugu. Initial comparisons are already revealing intriguing distinctions. Notably, Ryugu contains less water, highlighting the uniqueness of Bennu.

Bennu, a dark and carbon-rich asteroid discovered in 1999, stands at roughly 1,600 feet in diameter, a comparison that makes it taller than the Empire State Building, including its antenna. The intriguing prospect surrounding Bennu lies in the potential role played by asteroids like it in delivering the fundamental ingredients of life to Earth.

The Osiris-Rex mission commenced in 2016, culminating in its arrival at Bennu a few years later. Initial remote observations uncovered the presence of carbonate minerals on the asteroid, suggesting past hydrothermal systems involving hot water and carbon dioxide. This finding raises the possibility of ancient extraterrestrial water samples encapsulated in the minerals for billions of years.

In October 2020, a dramatic episode saw Osiris-Rex perform a deft maneuver to collect rock samples from Bennu. This maneuver, akin to a celestial pogo stick, involved the use of a sampling tool resembling an automotive air filter at the end of a robotic arm. Nitrogen gas propelled rocks and dust into a collection filter, while Osiris-Rex carefully retreated without making direct contact with Bennu. An unexpected malfunction of the collection tool's flap caused some collected material to escape into space, prompting mission managers to prioritize secure storage. The journey back to Earth commenced in May 2021.

With these celestial specimens in hand, researchers are poised to analyze the ratio of hydrogen to deuterium and explore its alignment with Earth's ocean composition. Further research will also focus on the potential presence of amino acids, the fundamental building blocks of proteins. Interestingly, meteorites found on Earth rapidly undergo contamination by terrestrial microorganisms, which is not the case with celestial amino acids.

The Bennu samples thus offer a unique opportunity to examine pristine amino acids of celestial origin, providing fresh insights into the origins of life. Moreover, the samples may contribute to the understanding of why life on Earth employs one mirror-image form of amino acids and complex organic molecules over the other. This, in turn, could offer insights into the cosmic forces or other factors that have influenced this choice.

The Osiris-Rex mission holds the potential for broader implications, including the prospect of safeguarding Earth against potential threats. Bennu is classified as a near-Earth asteroid, with a slim but not negligible possibility of a collision with our planet during close passages between 2175 and 2199. While not capable of causing global extinction, such an impact would be catastrophic on a local scale.

Although the mission has officially concluded, the spacecraft's journey continues. Following the release of the return sample capsule, the main spacecraft has charted a course towards Apophis, a 1,000-foot-wide asteroid set to pass within 20,000 miles of Earth in 2029. Following this close encounter, the spacecraft, now named Osiris-Apex (Origins, Spectral Interpretation, Resource Identification, and Security-Apophis Explorer), will enter orbit around Apophis.