Violent, catastrophic event created Geminid meteor shower

Using data from NASA's Parker Solar Probe mission, scientists have uncovered the dramatic and violent origins of Geminids - an awe-inspiring meteor shower that graces our night sky each December.

The origin of Geminids has long been a mystery. While most of the meteor showers have been attributed to comets, icy bodies that release gas and dislodge small fragments when they approach the Sun, the Geminid stream appears to emanate from an asteroid known as 3200 Phaethon. Unlike comets, asteroids are primarily composed of rock and metal and are not usually influenced by the Sun's heat.

"What's really weird is that we know that Phaethon is an asteroid, but as it flies by the Sun, it seems to have some kind of temperature-driven activity. Most asteroids don't do that," said Jamey Szalay, a research scholar at Princeton University and co-author on the science paper, recently published in Planetary Science Journal.

Each December, Geminid meteors zip across the night sky, producing one of the most intense meteor showers. Yet their origin has long been a mystery. Now, data from #ParkerSolarProbe may have uncovered how the Geminids came to be.Learn more here: https://t.co/tijexFN0Fi pic.twitter.com/Wmu68r3MUv

— NASA Sun & Space (@NASASun) June 14, 2023

The research builds upon earlier work conducted by Szalay and his colleagues from the Parker Solar Probe mission. Leveraging the probe's unique flight path - bringing it closer to the Sun than any previous spacecraft - the scientists obtained unprecedented observations of the dust grains shed by passing comets and asteroids within the innermost solar system.

Although Parker Solar Probe lacks a dedicated dust counter, it frequently encounters dust grains during its journey. These high-speed impacts generate distinct electrical signals, or plasma clouds, which are detected by multiple sensors on the probe's FIELDS instrument, which measures electric and magnetic fields in the vicinity of the Sun.

Utilizing data collected by NASA's Parker Solar Probe, the researchers employed modelling techniques to explore three possible scenarios for the formation of the Geminid stream. By comparing these models with existing ones derived from ground-based observations, they determined that the violent scenarios were the most consistent with the Parker data. This implies that a sudden, powerful event, such as a high-speed collision or a gaseous explosion, may have created the mesmerizing Geminids.