ASSOCIATED PRESS In this photo provided by NASA, a contrast-enhanced image produced from the Hubble images of comet ISON taken April 23, 2013 reveals the subtle structure in the inner coma of the comet. In this computer-processed view, the Hubble image has been divided by a computer model coma that decreases in brightness proportionally to the distance from the nucleus, as expected for a comet that is producing dust uniformly over its surface. ISON's coma shows enhanced dust particle release on the sunward-facing side of the comet's nucleus, the small, solid body at the core of the comet. This information is invaluable for determining the comet's shape, evolution, and spin of the solid nucleus. (AP Photo/NASA)
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STOCKHOLM >> It’s crunch time for a comet from the fringes of the solar system as it hurtles toward a close encounter with the sizzling sun.
Comet ISON is expected to get closest to the sun at 8:37 a.m. Hawaii time today.
At that point it will be only about 1 million miles away from the sun’s surface.
Scientists say it probably won’t be visible from Earth except via fleet of NASA telescopes and spacecraft. But if ISON survives — and it will be a few hours before that’s known — and returns past Earth, astronomers say it should be easily visible in the Northern Hemisphere early next month, just before sunrise and after sunset.