Hubble Captures Comet ISON

This NASA Hubble Space Telescope image of Comet C/2012 S1 (ISON) was photographed on April 10, when the comet was slightly closer than Jupiter's orbit at a distance of 386 million miles from the Sun (394 million miles from Earth).

Even at that great distance the comet is already active as sunlight warms the surface and causes frozen volatiles to sublimate. A detailed analysis of the dust coma surrounding the solid, icy nucleus reveals a strong jet blasting dust particles off the sunward-facing side of the comet's nucleus.

This image was taken in visible light with Hubble's Wide Field Camera 3. The blue false color was added to bring out details in the comet's structure.

About the colours

This image was originally black and white and recorded only overall brightness. These brightness values were translated into a range of bluish hues. Such color "maps" can be useful in helping to distinguish subtly varying brightness in an image.

About the data

The image was created from Hubble data from proposal 13198 : J.-Y. Li (Planetary Science Institute), P. Lamy (Laboratoire d'Astrophysique de Marseille), H. Weaver (JHU/APL), M. A'Hearn and M. Kelley (University of Maryland), M. Knight (Lowell Observatory), T. Farnham (University of Maryland), and I. Toth (Hungarian Academy of Sciences).