Why in the News?

NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security–Regolith Explorer) mission has delivered samples from asteroid Bennu, revealing amino acids, nucleobases, and signs of ancient saltwater, key components in the origins of life.

Key Findings of the Study:

14 out of 20 amino acids essential for proteins on Earth were found.
All five nucleo-bases used in DNA and RNA were detected, indicating prebiotic chemistry beyond Earth.
Ammonia & Formaldehyde compounds can react under suitable conditions to form complex organic molecules.
It thus supports the idea that asteroids delivered key building blocks for life to early Earth.
Calcite, halite, sylvite, and trona were found, indicating prolonged exposure to liquid water.
Similar briny conditions have been observed on Ceres and Enceladus, suggesting the solar system had widespread environments suitable for organic chemistry.
Life on Earth exclusively uses left-handed amino acids, but Bennu samples show an equal mix, raising questions about why life evolved with this preference.

Asteroid Bennu is a carbon-rich asteroid that orbits between Earth and Mars.
It is believed to be a primitive remnant of the early solar system, holding clues to the origins of life.
The asteroid is porous, with up to 60% empty space, affecting its collision potential with Earth in the distant future.
It periodically ejects material, classifying it as an active asteroid.
OSIRIS-REx was NASA’s first asteroid sample-return mission, launched in 2016 to study and collect material from Bennu’s surface.
- The spacecraft arrived at Bennu in 2018, mapped its surface for two years, and collected samples in 2020.
- It successfully returned the material to Earth in 2023.
The mission aimed to analyze Bennu’s composition, understand its water history, and study the organic molecules that may have played a role in the origin of life.

It strengthens the theory that asteroids contributed to life’s origins by delivering organic molecules and water to early Earth.
It confirms that essential ingredients for life were widespread in the early solar system, increasing the possibility of life beyond Earth.
It helps refine planetary defense strategies, as Bennu has a small chance of impacting Earth in the future.

[2011] What is the difference between asteroids and comets?

Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material.
Asteroids are found mostly between the orbits of Jupiter and Mars, while comets are found mostly between Venus and Mercury.
Comets show a perceptible glowing tail, while asteroids do not.

Which of the statements given above is/are correct?

(a) 1 and 2 only
(b) 1 and 3 only
(c) 3 only
(d) 1, 2 and 3