When ice meets fire

Comet ISON’s brush with the Sun as seen by the ESA/NASA SOHO satellite 27–30 November 2013.

ISON made its closest approach to the Sun during the evening of 28 November, passing just 1.2 million kilometres from the Sun’s visible surface. At first the comet was thought to have disintegrated during its fiery encounter, with just a remnant of its tail continuing along ISON’s trajectory. But, the next day, it seemed clear that something had survived after all – possibly a small chunk of ISON’s nucleus, along with a lot of dust. This progressively faded as it edged towards SOHO’s field of view on 30 November. Over the coming weeks scientists will be analysing the data collected during ISON’s encounter with the Sun to decipher the nail-biting chain of events that took place.

The shaded disc at the centre of the image is a mask in SOHO’s LASCO instrument that blots out direct sunlight to allow study of the faint details in the Sun's corona. The white circle added within the disc shows the size and position of the visible Sun. The images in this sequence coloured blue are from SOHO’s LASCO C3 instrument, which images the corona from about 3.5 solar radii to 30 solar radii; those in red are from LASCO C2, which images the corona from about 1.5 solar radii to 6 solar radii.