Observations indicate that the second tail formed between Oct. 2 and Oct. 8. As per experts, the new tail has developed on the northern side. Scientists will examine Hubble's data in the coming months to determine how the second tail developed.
NASA’s first planetary defense mission DART was a major success. The spacecraft not only managed to reach its target asteroid, but it also impacted the asteroid successfully. Images were taken not long after the impact and revealed the impact through photographic evidence. Later, Hubble and James Webb both observed the asteroid that was impacted. Ground-based telescopes also turned their cameras towards Dimorphos and revealed striking post-impact features. One of the main surprises that scientists saw was a massive tail of debris spanning thousands of kilometers from the asteroid. Dimorphos has a diameter of 170 meters (560 feet), while Didymos has a diameter of 780 meters (2,560 feet).
During a planetary defense test on Sept. 26, DART crashed into Dimorphos, a small moonlet of Didymos, to change Dimorphos’ orbit. Approximately 32 minutes were cut out of Dimorphos’ original 11-hour, 55-minute orbit around Didymos by DART. Scientists were in for a surprise when they turned Hubble towards Dimorphos a second time. Recent Hubble space telescope images of the Didymos-Dimorphos asteroid system show two tails of dust ejected. The evidence here shows the effects of NASA’s Double Asteroid Redirection Test (DART). Through repeated Hubble observations over the last several weeks, scientists have been able to reconstruct the evolution of the debris cloud over time.
Based on the observations, it appears that the ejected material, or “ejecta,” has expanded and faded in brightness over time, largely in line with expectations. Interestingly, the twin tails are a surprising development, although comets and active asteroids exhibit similar behavior. Furthermore, in the Hubble observations, the double-tail is observed in the highest quality. Hubble observed the system 18 times after the impact. Observations indicate that the second tail formed between Oct. 2 and Oct. 8. There is still confusion regarding the relationship between the comet-like tail and other ejecta features visible in Hubble and other telescope images. Currently, the Investigation Team is looking into this. As per experts, the new tail has developed on the northern side. Scientists will examine Hubble’s data in the coming months to determine how the second tail developed. The team will examine several possible scenarios.
Click here for a video of the impact.