On the same day that NASA announces the thing that struck the Giant Planet last year was probably an asteroid, another possible impact has been recorded by the same guy who announced the original.
Reanalysis of the Hubble Space Telescope images of the impact suggest that it was a solid object half a kilometre wide based on observations showing the strike was cleaner that the cometary impacts of 1994, which included a ‘halo’ of disruptions due to cometary fragments and small particles. This suggests the impact was due to a comet.
In new images, Anthony Wesley has identified what he believes to be a fireball on the (now single banded) disc of Jupiter. However, continued observations show that this time there was no impact scar visible, suggesting if an object did hit, it exploded higher up in the atmosphere than the layers associated with scarring and upwelling of materials. This would be equivalent to the many asteroids we’ve seen on Earth exploding before striking the ground.