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Comet ISON: Pop or Fizzle?

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
In this Hubble Space Telescope composite image taken in April 2013, comet ISON floats against a seemingly infinite backdrop of numerous galaxies and a handful of foreground stars. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

Will the much talked about comet ISON, discovered by Russian amateur  astronomers last year, turn out to be what some are calling the ‘comet of the century’ ? Not likely, says one researcher who has just concluded a preliminary study using the latest observations of the icy interloper. (Related: “New Comet Discovered.”)

Astronomer Ignacio Ferrin, from the University of Antioquia in Medellin, Colombia, believes that comet C/2012 S1 ISON may possibly  fall apart before even reaching its closest encounter with the sun later this fall.

Stargazers were initially very excited when astronomers calculated the comet’s orbit and they realized it would be skimming the sun’s surface by only 700,000 miles (1.1 million kilometers) on November 28, 2013. But continual observations by both professional and amateur telescopes, including Hubble, have since shown that the comet has not brightened as expected.

“Comet ISON has presented a peculiar behavior,” said Ferrin in a press statement.

“The light curve has exhibited a ‘slowdown event’ characterized by a constant brightness with no indication of a brightness increase tendency. This slowdown took place around January 13, 2013. For 132 days after that date, and up to the last available observation, the brightness has remained constant.”

Ferrin interprets this lackluster behavior as meaning that the comet may not live up to all the hoopla.

That’s because during its closest encounter with the sun, the comet’s three-mile (five-kilometer) wide icy core – in the worst case scenarios- will either be torn apart by intense solar gravitational forces, or simply melted away by the scorching 2,700 degree temperatures, Ferrin says.

The consensus in the astronomical community is that it is especially unlikely that ISON will flare up to be as bright as the full moon, as some media accounts have reported.

For now, however, the comet is still currently out between the orbits of Mars and Jupiter, hurtling towards the Sun at 48,000 miles (77,000 kilometers) an hour. The latest infrared views from NASA’s Spitzer Space Telescope—taken in June—shows ISON’s nucleus spewing out a healthy 186,000-mile-long (299,000-kilometer-long) tail of carbon dioxide and dust as it melts due to the sun’s heat.

Will comet ISON blossom into a naked-eye comet, sporting a long, beautiful tail across the sky? Comets are notoriously unpredictable and can surprise even experts. Unfortunately, it’s now a wait-and-see game since the comet is currently lost in the glare of the sun and will only be visible again in early September.

One thing is for sure, ISON will make an uncomfortably close approach to the sun in just a few months. Thanks to an armada of telescopes on Earth and in space trained on this cosmic event, we will be witness to a rare spectacle no matter what’s in store for this sun-grazer.

 

Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.

Comments

  1. syney
    19 mississippi
    October 14, 2013, 10:59 am

    Comet ison is the coolest comet on earth i cant what till Nov.28,2013

  2. MICHAL SADLON
    September 4, 2013, 5:51 am

    interesting way to follow ISON – real-time visualization
    http://www.solarsystemscope.com/ison

  3. anthony
    nottingham england
    August 5, 2013, 6:11 pm

    the knowing was a film about the suns super flares.

  4. spinning star
    August 5, 2013, 2:19 pm

    I don’t give a dime to the doomsday theorists. But I see the story of Nibiru is mentioned anywhere in the anctient worlds, maps (space cartography) we don’t believe are anctient and not “just” centuries or milenias old.
    We have a crashing moon loose outhere … and we all know there’s between Mars and Jupiter a thick, some refere as “too much material for a single planet” asteroid field (or inner belt), and an external icy comet also field or belt)…
    I think Celes, the planet of the angels and it’s twin planet orbiting togheter turnning each other had an anctient “ball 8 pull crash” terror act, from “big, big enemies men always had”… hidden in power positions, infiltrated… nets…

  5. Stephen Y
    3rd Rock from the Sun
    August 2, 2013, 2:57 pm

    If you continue to hold that it a gravitationally controlled universe/solar system instead of all of the evidence pointing to the stronger electromatic model, you won’t understand that the “brightness” is dependent upon the relative charge between the sun and the comet.

  6. Lea Beckman
    minnesota
    August 1, 2013, 2:32 pm

    I hope this is not super massive armagedon, if it is we are doomed. it’s kinda like the movie Knowing.

  7. Comet C/2012 S1 ISON Facebook Page
    August 1, 2013, 9:33 am

    Comet C/2012 S1 ISON Facebook Page – http://facebook.com/C2012S1

  8. włochaty
    July 31, 2013, 4:52 pm

    The best comet ISON flyby simulation there is:

  9. william cook
    nc
    July 31, 2013, 7:27 am

    i’m interested pls keep me posted