SOHO prepares for comet McNaught

Track of comet McNaught through SOHO's coronagraph LASCO C3 More Information ROLLOVER Credits: ESA, NASA SOHO/LASCO team

Comet McNaught will pass within a fifth of the distance between the Earth and the Sun. As the comet approaches the Sun, the amount of dust and gas it releases will increase dramatically, causing the comet to become extremely bright. "This might become the brightest comet SOHO has ever seen," says Bernhard Fleck, SOHO Project Scientist.

The material ejected from the comet forms the tails. There are two tails, the dust tail and the gas – or ion – tail. The dust tail is the brighter and is formed by the intense sunlight forcing dust particles away from the comet. The solar wind, a constant stream of material flowing from the Sun, drags ionized gas from the comet to create the ion-tail.

Comet McNaught More Information ROLLOVER Credits: Roger Johansen

Comet McNaught is moving through space on an inclined orbit. This will carry it above the Sun’s north pole and across the Sun’s equator, a place where there is a reversal of the magnetic properties of the solar wind. Crossing this boundary could cause the comet’s ion-tail to fragment. Observations of such events are generally very rare, so SOHO's images of comet McNaught constitute an exciting opportunity for scientists.

After SOHO's work is finished, the comet will emerge from the Sun’s glare and become visible again to earthbound sky watchers in the Southern Hemisphere. "It could become a really bright object in the twilight sky," says Fleck. The ghostly veils of a bright comet are amongst the most spectacular of sights that can be seen in the night sky.

Between 12 and 15 January, Comet McNaught will not be visible from Earth but everyone can still track the comet's passage near the Sun by looking at the SOHO images at http://www.sflorg.com/spaceweather.html

Source / Credit: ESA