Home » , » New Comet ISON - You Can see November 20~28 (2013)

After over a decade punctuated by only sporadic bright comets such as 17P/Holmes, C/2011 W3 Lovejoy and C/2006 P1 McNaught, 2013 is recognized as “The Year of the Comet” by the astronomical community. During 2013, we’ve already had two naked eye comets such as C/2012 F6 Lemmon and C/2011 L4 PanSTARRS. But, all eyes are now on Comet C/2012 S1 ISON as it plunges towards perihelion (The closest point to the Sun in a comet's orbit) on November 28th. It is skimming just 730,000 miles above the sun’s surface.


Comet ISON as seen from the Hubble Space Telescope on April 30th, 2013. (Credit:HubbleSite.org/Go/ISON)

Comet C/2012 S1 was first spotted 585 million miles away in September 2012 by Artyom-Kislovodsk and VitalyNevsky using the International Scientific Optical Network’s (ISON) 0.4 meter reflector. This is the reason the comet C/2012 S1 is commonly called as comet “ISON”

The passage of ISON into the inner solar system has been the most anticipated apparition of a comet since Hale-Bopp in 1997.Many backyard observers will get their first good look at Comet ISON during this month.

Scientific Importance of ISON 

As in many ofitscounterparts comet ISON started its journey from the Oort cloud region of our solar system and is now travelling toward the sun.A comet’s journey through the solar system is perilous and violent due to the giant ejection of solar material from the sun which could rip its tail off.

However, comet ISON has already started this journey.This is its very first trip around the sun. Therefore its top layers never have been lost by the solar radiation. As a result of that ISON is still made of primeval (original) matter from the earliest days of the solar system’s formation.

Scientists will point as many ground-based observatories as they can and at least15 space-based instruments towards the comet in order to learn more about the formation of the solar system.Even if the comet does not survive due to the intense radiation and pressure of the sun while it approaching towards the sun, tracking its journey still help scientists understand what the comet is made of, how it reacts to its environment, and what this explains about the origins of the solar system. As it closes to the Sun the scientists can also learn more about the Sun itself by observing the way how the comet and its tail interact with the vast solar atmosphere.

Where is ISON in the Sri Lankan sky in November?

Despite of the prediction of the disintegration (the comet happens to break apart along the way.) the comet ISON is still on the upswing. ISON’s tail should grow longer and brighter as the comet nears the Sun and warms up, which generates more gas and dust. During the final two weeks of October, ISONs speed has increased. The closer it gets to the sun, the faster it travels. The comet will be sweeping in front of the constellation Leo in October. Then it will pass near the planet Mars which is in Leo constellation. The comet’s separation from Mars grew from 0.9° on the 17th October to nearly 7° by the 31st October. ISON was easily seen in the eastern sky before dawn with a pair of binoculars since the 2ndweek of October,and from the 3rd week of November onwards it is predicted that ISON should be seen with an unaided eye. The comet is reaching Virgo by the 1st week of November.

The following table may help Sri Lankan backyards astronomers to locate ISON at 5.00AM (Sri Lankan Time)

The best time to observe it would be 1 hour before sunrise. The observing location should be clear of buildings, trees or any other obstructionsin the eastern direction.
The Arthur C. Clarke Institute will announce programs and activities later that will be organized to observe the ISON.


The location of Comet ISON relative to ACCIMT during the period of 1st to 25th November 2013.The position of the comet is almost same for all observers in Sri Lanka. The movement of the comet with respect to Horizon Coordinate System is shown.

Thanks: Arthur C Clarke Institute for Modern Technologies, Sri Lanka