American scientists have uncovered the mystery behind 3200 Phaethon, the asteroid responsible for the Geminid meteor shower.
According to Sci-News, meteor showers typically originate from comets, as Earth passes through their dusty tails. The reason 3200 Phaethon exhibits this unusual behavior is that it has been observed to “mimic” comets. The key explanation lies in the phenomenon of massive sodium outgassing whenever the asteroid approaches the Sun.
This strange process causes 3200 Phaethon to develop a tail of dust and debris, radiating a glow similar to that of a comet, even though it remains classified as an asteroid.
3200 Phaethon approaching the Sun – (Image: NASA/JPL-Caltech/IPAC)
According to the research team led by NASA, this phenomenon occurs when the asteroid reaches the region near the Sun during its 524-day orbit. At this point, it is nestled within the orbit of Mercury, with its surface heated to about 750 degrees Celsius. This intense heat causes sodium to evaporate vigorously, creating an orange glow under telescopic observation.
Dr. Bjorn Davinson from NASA’s Jet Propulsion Laboratory, a member of the research team, stated that asteroids like 3200 Phaethon have very weak gravity, making it easy for fragments to be ejected from their surface or cracks. Therefore, even a small amount of sodium loss can lead to debris being swept away, resulting in a large dust tail.
This phenomenon also explains why this asteroid has a very low sodium content, as this element is continuously lost.
To arrive at these conclusions, scientists modeled the heating effects on the asteroid based on data collected by NASA, comparing the elemental composition before and after it flew near the Sun and identifying the elements that were lost.
3200 Phaethon is a carbonaceous chondrite asteroid, a group of extremely rare objects from the early solar system, believed to hold secrets about the origins of life on Earth. The study was recently published in the Planetary Science Journal.
