What if Asteroid Ryugu Hit Earth?
What if Asteroid Ryugu Hit Earth? https://asteroidday-uploads.s3.eu-central-1.amazonaws.com/wp-content/uploads/2023/04/19001747/ruygu.png 480 270 Asteroid Day https://asteroidday-uploads.s3.eu-central-1.amazonaws.com/wp-content/uploads/2023/04/19001747/ruygu.png
Scientists have calculated what would happen if the spinning-top-shaped asteroid Ryugu hit our planet. Predicting the outcome of such a collision was possible thanks to the analysis of samples that arrived on Earth after being collected by JAXA’s Hayabusa2 spacecraft.
The results were presented by Satoshi Tanaka, professor at the Department of Solar System Sciences at JAXA, during the 8th IAA Planetary Defense Conference in Vienna, Austria, which took place in the first week of April and was supported by Asteroid Day.
According to Tanaka, the Hayabusa2 mission was successful in an experiment in which two one-kilogram projectiles were launched at a speed of 2 kilometres per second, forming a crater of approximately 20 metres in diameter on the asteroid. The cohesive strength of the rock was to be extremely low with a density only slightly higher than water with very high estimated porosity.
Because of its low mechanical strength compared to normal rocks, Ryugu has been classified as a rubble pile asteroid, something that should be considered if it is on a collision course with Earth. If the same method adopted during the DART mission, which impacted an asteroid’s moonlet in 2022, is used, the asteroid could break into several pieces.
However, if no methods were applied to deflect Ryugu and the asteroid entered the earth’s atmosphere at a speed of 17 kilometres per second at an angle of 45°, it would break up about 40 to 35 kilometres above the planet’s surface.
The explosion would cause an effect similar to the Chelyabinsk event that occurred in 2013, when an asteroid exploded 30 kilometres from Earth, leaving several injured when glass in the area broke from the generated shock wave. However, this asteroid was only 20 metres in diameter while Ryugu measures approximately 900 metres.
Tanaka pointed out that because we still do not know Ryugu’s resistance properties precisely, it is not possible to predict the size of the pieces that would fall to Earth. According to him, Ryugu’s tensile strength could be more than two orders of magnitude greater than current estimates, which could influence its effects on our planet. The returned sample is currently in the process of initial analysis. Internal fracture analysis is important to enable a more accurate assessment of the impact of Ryugu-like asteroids on Earth.
Learn more about this asteroid:
Eyes on Asteroids – Ryugu
Hayabusa2 touch down – video
