400 Billion Won 'Foolish Act'?… NASA Had It All Planned [Reading Science]

The Story of the DART Spacecraft Launched on the 24th

[Asia Economy Reporter Kim Bong-su] Is NASA's $400 million project a 'foolish stunt' or a heroic act to save humanity from threats? These are the discussions surrounding the DART (Double Asteroid Redirection Test) spacecraft launched by the U.S. National Aeronautics and Space Administration (NASA) on the morning of the 24th. This project is an unprecedented mission involving a massive investment of $325 million (approximately 400 billion KRW) to collide a spacecraft with an asteroid. Let's take a closer look at the true purpose of this project as revealed by NASA.

◇ Altering an Asteroid's Trajectory by Spacecraft Collision

The goal of the DART project is to conduct preliminary research to prepare for the possibility of asteroids?numbering in the billions within our solar system?colliding with Earth. The main objective is to send a spacecraft to collide with an asteroid and observe any changes in its trajectory to collect data. The DART spacecraft, roughly the size of a small car, will travel through space for about a year after launch and is scheduled to collide with Dimorphos (diameter 160m), a satellite orbiting the Didymos asteroid (diameter 700m), located approximately 11 million kilometers from Earth. An Italian Space Agency small satellite launched alongside DART will record the entire process, and the European Space Agency (ESA) plans to launch the Hera probe in 2024 to investigate the effects of the collision, including changes in the mass and orbit of the Dimorphos satellite. NASA stated, "After the DART spacecraft collision, observations through astronomical telescopes will measure whether Dimorphos's trajectory has changed," adding, "This project will promote international cooperation to address the global issue of planetary defense."

Asteroid impacts pose significant threats to life on Earth. A massive asteroid over 10 km in diameter, believed to have struck the Yucat?n Peninsula in Mexico about 65 million years ago, caused the extinction of the dinosaurs that dominated Earth at the time. A 50-meter asteroid that fell in Russia in 1908 generated a shockwave equivalent to 15 atomic bombs, causing tremendous damage. According to the Korea Astronomy and Space Science Institute, there are about 23,000 asteroids orbiting near Earth, with over 2,000 estimated to pose a threat to our planet. Among these, 3 to 4 asteroids have a relatively high probability of colliding with Earth, drawing significant attention. Apophis, known as the "God of Destruction," which passed close to Earth in March, was once feared due to its potential collision with Earth in 2068. However, NASA recently announced that Apophis's orbit has become irregular, eliminating the possibility of collision within the next 100 years. Apophis is expected to approach Earth as close as 37,000 km in April 2029, and South Korea is also pursuing exploration efforts.

Additionally, three asteroids?Bennu (101955 Bennu), 1950 DA, and 2007 FT3?are known to have collision probabilities with Earth within 100 years of 0.037%, 0.012%, and 0.00014%, respectively. In particular, Bennu is expected to approach Earth in 2182 with a collision probability of 1 in 2,700. Based on the results of this experiment, NASA plans the 'HAMMER' spacecraft project to alter Bennu's trajectory. Furthermore, in 2026, NASA plans to launch the 'NEO Surveyor,' a space telescope capable of monitoring two-thirds of small asteroids within 48 million km of Earth.

Meanwhile, research continues on destroying or altering asteroid orbits using nuclear bombs or metal rods. Recently, Dr. Patrick King and his research team at the Johns Hopkins University Applied Physics Laboratory (APL) published simulation results showing that detonating a 1-megaton nuclear bomb on a 100-meter-long asteroid shattered it, causing 99.9% of the fragments to miss Earth. Additionally, Professor Philip Rubin's team at the University of California is researching technology to destroy asteroids by launching missiles equipped with metal rods, similar to South Korea's Hyunmoo-4 missile (bunker buster), to generate shockwaves. In 2016, Russian scientists considered a project to destroy the Apophis asteroid using an intercontinental ballistic missile (ICBM), but it was canceled due to concerns about adverse effects on Earth.

NEXT-C, an ion propulsion engine developed by NASA.

◇ Why Not Just Do It in a Laboratory?

There remains skepticism about whether it is worth spending 400 billion KRW on this project. Some argue that creating sophisticated computer models and conducting virtual tests would be more economical and efficient. However, NASA explains that because asteroids are complex objects with diverse physical properties, internal structures, shapes, and geological features, testing in 'real-world conditions' is essential. NASA stated, "Conducting real-world tests on asteroids with largely unknown physical properties is crucial to evaluate and improve current models to address potential future threats from Earth-threatening asteroids."

Testing the latest space technologies is also an important reason. The DART spacecraft is equipped with a small autonomous real-time navigation system (SMART Nav) developed by Johns Hopkins APL, which can independently navigate its trajectory without communication or assistance from Earth. This advanced system can distinguish between Didymos and Dimorphos through image capture and operates autonomously starting four hours before collision.

Innovative solar power technology is also being tested through the DART project. Two foldable solar panels developed by APL and installed on the DART spacecraft can be folded and unfolded and produce more than three times the power of conventional solar panels. Additionally, NASA plans to test its innovative Xenon (NEXT-C) thruster. The NEXT-C solar electric propulsion system serves as an auxiliary propulsion device for the DART spacecraft, and NASA intends to assess its potential for future deep space exploration missions. Ion propulsion systems accelerate ionized particles with positive or negative charges within an electric field to generate thrust by reaction, offering efficiency up to ten times that of chemical fuels.