This strange space rock has long baffled scientists about its asteroid-like behavior, but it has revealed yet another intriguing feature.
In 2009, NASA’s Solar-Terrestrial Observatory (STEREO) spacecraft confirmed that asteroid 3200 Phaethon was doing something unusual in its orbit. It brightened and had a sizable tail as it reached its closest point to the Sun in its 524-day orbit.
This was already a strange occurrence, as comets have tails due to their icy structure rather than rock-and-metal asteroids. It has long been thought to be dust ejected from the surface of an asteroid.
Now scientists have discovered that there is no visible dust. In fact, it’s an impressive tail made of sodium gas.
“Our analysis shows that Phaeton’s comet-like activity cannot be explained by dust of any kind,” said lead author Qicheng Zhang, a PhD student at Caltech. I’m here. “Comets are often brightened by sodium emissions when they are very close to the Sun, so we suspected that sodium might play an important role in Phaethon’s brightening as well.”
Previous studies had found sodium to be responsible for the “fizz” on the asteroid’s surface. Closer to the sun, the Phaethon, which is about 3.9 miles (6.3 km) in diameter, has a surface temperature of about 1,390 °F (750 °C), vaporizing certain substances.
The discovery was made using NASA’s two solar observatories. The Solar and Heliospheric Observatory (SOHO) spacecraft was employed to observe asteroids through two filters that can distinguish between sodium and dust, respectively. The researcher then accessed his STEREO and SOHO imaging archives, and between 1997 and 2022 he discovered the occurrence of Phaeton’s tail at 18 solar approaches.
ESA/NASA/USNRL/Carl Battams
The SOHO filter confirmed the suspicions. Using the sodium-detecting lens, the asteroid’s tail was noticeably brighter, allowing scientists to see how the asteroid changed shape and intensity as it moved along its path. No trace of dust was observed on the other filter.
“Not only have we obtained some really impressive results that have overturned 14 years of thinking about a well-scrutinized celestial body, but we have also had a number of observations from two solar physics probes, SOHO and STEREO, that were never intended to study phenomena. We did this with data, like this,” said Karl Battams, team member at the Naval Research Laboratory.
ESA/NASA/Zhang Chicheng
The discovery further deepens the mystery of Phaethon, which orbits closer to the Sun than other named asteroids, is one of the few asteroids that appear blue on its surface, and is part of the annual Geminid meteor shower. source. Comets are commonly responsible for meteor showers.
In 2017, Phaethon, identified in 1983 and named after the son of Helios, the sun god in Greek mythology, passed by Earth, but was still 6.4 million miles (10.3 million km) from Earth. It won’t go back in this direction again until 2093.
This research Journal of Planetary Science.
Source: NASA
