The Hubble Space Telescope has captured the clearest picture ever taken of Comet ISON, which is expected to light up the sky when it passes closer to Earth later this year.
The Hubble photographed Comet C/2012 S1 (ISON) on April 10th, when it was closer than Jupiter’s orbit at a distance of 386 million miles from the Sun, and 394 million miles from Earth. Experts at NASA say it will get easier to see ISON when the comet flies closer to the sun in late November.
Even though it’s farther away from the sun now, the comet is already warming up as sunlight hits it’s surface and causes the frozen frozen volatiles to sublimate. Comets become more active as they near the inner solar system, where the Sun’s heat evaporates their ices into jets of gases and dust. NASA says 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.
ISON’s orbit will bring it closest to the Sun, of 700,000 miles on November 28, 2013.