The Last Gift of the Dying 'Hwaseong Geologist' [Reading Science]

Detection of Seismic Waves from Small Nuclear Bomb-Scale Meteor Impact in December Last Year
Crucial Contribution to Location Identification and Filming

Insight. Photo by NASA, USA

[Asia Economy Reporter Kim Bong-su] The InSight lander, known as the 'Mars Geologist,' which was dying as its solar panels were covered with dust, has left its final achievement. After two meteorites with the power equivalent to small atomic bombs fell on Mars at the end of last year, it detected a powerful earthquake and made a decisive contribution to confirming that a large impact crater was formed based on this.

According to the international academic journal Science on the 28th, a research team led by Kim Do-yeon from the Geophysics Research Institute at ETH Zurich in Switzerland announced that InSight successfully detected seismic waves generated by the largest meteorite impact ever observed on Mars on December 24 last year.

The two meteorites that struck Mars at that time were each large enough to deliver an impact equivalent to a small nuclear bomb, causing a massive earthquake on Mars. Scientists were able to study the characteristics of the Martian crust thousands of kilometers away from InSight through these seismic waves. They are also seeking answers as to why the area where InSight landed is composed of soil so hard that drilling is impossible. In particular, a U.S. research team, based on InSight's seismic wave observations, mobilized the Mars Orbiter to successfully identify and photograph a large impact crater over 130 meters in diameter created by the meteorite collision.

Mars meteorite impact crater. Photo by NASA

InSight landed on the Elysium Planitia near the Martian equator in November 2018. Unlike other rovers equipped with wheels that move around, it was fixed in one place and planned to perform missions such as drilling the ground to install seismometers and heat sensors. True to its nickname as the 'Mars Geologist,' it aimed to study the soil, geology, and internal structure of Mars. However, drilling operations failed due to an unusually hard surface soil layer. To make matters worse, the solar panels were covered with dust, causing a sharp decline in power generation, and its lifespan is expected to end within weeks.

InSight has detected over 1,300 seismic events and played a significant role in determining the size of Mars' core and the thickness of its crust. Recent research has shown that Mars' mantle contains more iron than Earth's. Marsquakes mostly occur in the Cerberus Fossae region about 1,500 km from InSight, where magma injection underground is believed to cause vibrations. These are generally small earthquakes around magnitude 2 to 3, but on May 4, a somewhat strong quake of magnitude 4.7 occurred. Additionally, seismic events were observed twice last year in August and September in locations other than Cerberus Fossae.