Astronomers around the world will have a chance to observe the closest asteroid approach of the year on March 21. Credit: Pixabay

Giant Asteroid from Ancient Solar System to Fly Past Earth on March 21

Asteroid 2001 FO32 will be the largest and fastest asteroid to approach Earth in 2021.


This month will be marked by the closest approach of the largest asteroid that will pass near our planet in 2021 – Asteroid 2001 FO32. The celestial object has been categorized as “potentially dangerous” as it orbits closer to Earth than the minimum safe distance.

Nevertheless, there is no reason for panic. On March 21, the asteroid will be at the closest approach distance to Earth, which will fluctuate about 2 million km. Thus, it will not be able to cause harm to our planet due to its remoteness from it.

It is curious that asteroid 2001 FO32 is also moving faster than most asteroids due to its unusually inclined and elongated circumsolar orbit.

Here is an illustration of the orbit of asteroid 2001 FO32 which will come close to Earth on March 21. It has an unusually elongated orbit and a single revolution around the sun takes 810 days. Credit: NASA / JPL
Here is an illustration of the orbit of asteroid 2001 FO32 which will come close to Earth on March 21. It has an unusually elongated orbit and a single revolution around the sun takes 810 days. Credit: NASA / JPL

Scientists have been monitoring this asteroid for nearly 20 years now since it was discovered on March 23, 2001. They have calculated its trajectory until 2196 which means that it poses no risk to us for at least 200 years.

Initial estimates suggested that asteroid 2001 FO32 is roughly about a kilometer wide. Various sources report different diameters but the latest official observations have given it much smaller dimensions – from 440 to 680 meters in diameter.

No matter if it is 440 or 680, it is still the largest asteroid to come this close to our planet in years. Although astronomers have been monitoring it for 20 years, there is still a lot to learn about it and the close approach on March 21 will give experts the greatest chance to study it.

How will NASA study the asteroid during its approach on March 21?

NASA plans to use several different observatories around the world to conduct a series of studies on asteroid 2001 FO32 as it approaches Earth.

Understanding the geology of a celestial object from Earth is no easy task but it can be achieved with the help of NASA’s Infrared Telescope Facility in Hawaii. Scientists will have to study the spectrum of sunlight that hits the surface as its reflection will reveal the chemical composition of the surface. Once scientists get a better idea of the minerals that the asteroid contains, they can then understand its mass and even the nature of its origin.

Additional radar observations may be carried out although it has not been confirmed yet. This operation will likely be carried out by NASA’s Deep Space Network which includes three ground-based observatories on three continents. Radar observations could not only help understand the true dimensions of asteroid 2001 FO32 but also its surface features that are necessary to understand the origin of the object and its history.

Scientists at NASA’s JPL have suggested that 2001 FO32 may have its own small moon as a significant percentage of similar-sized asteroids have their own satellites.

Will amateur astronomers be able to observe the asteroid?

According to NASA, asteroid 2001 FO32 will be visible with the help of moderate size telescopes but finding it could be difficult. You will be able to observe it for several nights before and after the closest approach if you live in the southern hemisphere or at low latitudes in the northern hemisphere.

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Gohd, C. (2021, March 11). A big asteroid will ZOOM safely past Earth on March 21, NASA says.
Irizarry, E. (n.d.). Biggest asteroid to pass Earth in 2021 also one of the fastest.
NASA – JPL. (n.d.). Asteroid 2001 FO32 will safely pass by Earth March 21.
Science X. (2021, March 12). Large asteroid to pass by Earth on march 21: Nasa.


Written by Vladislav Tchakarov

Hello, my name is Vladislav and I am glad to have you here on Curiosmos. As a history student, I have a strong passion for history and science, and the opportunity to research and write in this field on a daily basis is a dream come true.

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