Comet ISON Brings Holiday Fireworks
This July 4th the solar system is showing off some fireworks of its own.
Superficially resembling a skyrocket, Comet ISON is hurtling toward the Sun
at a whopping 48,000 miles per hour.
Its swift motion is captured in this image taken May 8, 2013, by NASA's Hubble Space Telescope. At the time the
image was taken, the comet was 403 million miles from Earth, between the
orbits of Mars and Jupiter.
Unlike a firework, the comet is not combusting, but in fact is pretty cold.
Its skyrocket-looking tail is really a streamer of gas and dust bleeding off
the icy nucleus, which is surrounded by a bright, star-like-looking coma. The
pressure of the solar wind sweeps the material into a tail, like a breeze
blowing a windsock.
As the comet warms as it moves closer to the Sun, its rate of sublimation will
increase. The comet will get brighter and the tail grows longer. The comet is
predicted to reach naked-eye visibility in November.
The comet is named after the organization that discovered it, the Russia-based
International Scientific Optical Network.
This false-color, visible-light image was taken with Hubble's Wide Field Camera 3.
Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)