Important Announcement:

We announce the start of an observing campaign to study incoming Oort Cloud comet C/2013 A1 (Siding Spring), which is predicted to have an extremely close approach to Mars of 134,000km +/- 5,000km on October 19, 2014.

Early observations taken now will help modelers assess what hazard, if any, the comet poses to the spacecraft currently orbiting and roving Mars. Later observations starting this summer when the comet is better seen from Earth will be able to characterize the composition and production rates from the comet, which will aid the newly arriving NASA MAVEN spacecraft. Observations taken during the close encounter will observe an event unique in modern history: a planet flying through a comet's coma.

We have a new website dedicated to this campaign: This new site is the primary focus of our efforts now, so if you're looking for new blog posts and info from the CIOC team, you should head over to that site.

--The CIOC

Welcome to the CIOC!

An enhanced image of Comet ISON, from Hubble Space Telescope data taken in May 2013

The NASA Comet ISON Observing Campaign is a NASA-backed program tasked with encouraging and facilitating a massive, global and celestial observing campaign for Comet C/2012 S1 (ISON).

In November 2013, comet C/2012 S1 (ISON) will pass the Sun at just 0.012AU (~1.1-million kilometers above the solar surface), classifying it as a Sungrazing Comet, and potentially a spectacular one! Comet ISON is still far away, and as both a dynamically new object and a sungrazing comet, it is difficult to predict exactly how bright the comet will become in November. However, there does exist the potential for this to be one of the brighter comets of the past century. And even if it does not live up to that lofty goal, it will nonetheless be a relatively large sungrazing comet, fresh from the Oort Cloud, getting its first ever experience with the Sun's immense gravitational pull and intense radiation. Regardless of ISON's brightness, these facts alone make it an extremely attractive target to astronomers, and one that is potentially rich with new science. To that end, NASA has requested a small committee of cometary experts to be formed and coordinate an observing campaign for this comet, under the assumption that it will enter the inner solar system during the middle of 2013 as at least a reasonably bright comet, and provide us with an unprecedented opportunity to witness the vaporizing of pristine solar system material as it nears perihelion.

This CIOC website is the hub for up-to-date information about Comet ISON, information on participation in the Campaign and how you can help, links to relevant observatories and programs, and blog postings from CIOC Team members. Over the coming weeks, as ISON makes its close approach to the Sun and an increasing volume of observations are made, you can expect to see a corresponding increase in the number of articles, blog posts and images appearing on the site.