Asteroid Watch: NASA’s Popular Targets

By Vandya Rai

June 30, 2022

4 Vesta

The second most massive body in the main asteroid belt, Vesta accounts for almost 9% of the total mass of all asteroids. Due to its spherical form, it is nearly classified as a dwarf planet. It even has a crust, mantle, and core, unlike other asteroids, and much like our planet. 

Image Source: NASA

FOUND IN 1807

243 Ida

The first asteroid discovered to have its own moon. The moon was named Dactyl, when it was observed in 1994. Ida is located in the main belt between Mars and Jupiter.

Image Source: NASA

FOUND IN 1884

433 Eros

The first asteroid to have a spacecraft orbit around it and land on it, in 2000. It was also the first near-Earth asteroid found in 1898. Back then, astronomers used Eros to calculate the mass of the Earth-moon system and the value of the astronomical unit.

Image Source: NASA

FOUND IN 1898

Didymos

Didymos and its orbiting moonlet, Dimorphos make up a binary asteroid system. They pass by close to Earth but are not a threat. The duo is chosen for NASA’s first mission to test planetary defence technology to protect Earth from hazardous asteroid collisions someday.

Image Source: NASA

FOUND IN 1996

10199 Chariklo

The first asteroid found to have a ring system. The rings are believed to be between 3-7 kilometres wide. Chariklo orbits between Saturn and Uranus in the outer solar system.

Image Source: Wikipedia

FOUND IN 1997

25143 Itokawa

The first asteroid from which samples were collected and brought to Earth. Its dust revealed that Itokawa is the remains of a much larger object that was shattered by a collision. Its orbit around the Sun crosses those of both Earth and Mars.

Image Source: NASA

FOUND IN 1998

101955 Bennu

Bennu pays Earth a visit, every 6 years. The closest it will ever approach us is sometime in the 22nd century, with a 1‐in‐2,700 chance of any impact. Bennu was named by a 9-year-old. It is slightly wider than the length of the Empire State Building.

Image Source: NASA

FOUND IN 1999

Apophis

The asteroid that will harmlessly pass close to Earth on April 13, 2029, at 31,900 kilometres from our surface. Apophis will come between Earth and our moon during its flyby. It is about the size of 3.5 football fields.

Image Source: NASA

FOUND IN 2004

2019 OK

With little warning, this football-field-sized asteroid safely passed close to Earth on July 24, 2019. It approached within 65,000 kilometres of the planet’s surface, and will not come so close again for at least 200 years.

Image Source: Wikimedia Commons

FOUND IN 2019