Stargazers in for a treat as green comet 'the size of Jupiter' streaks past Earth

Stargazers in for a treat as green comet 'the size of Jupiter' streaks past Earth

Last updated at 2:32 PM on 23rd February 2009

Stargazers could be in for a treat tonight as a spectacular double-tailed green comet flashes past Earth.

There is nothing to be concerned about: the celestial body, named 'Lulin', comes no closer than 38 million miles - or 160 times farther than the moon.

But the Jupiter-sized ball of ice and gas will still be visible to the naked eye.

The stellar traveller is very active, shedding nearly 800 gallons of water each second on its journey around the Sun. That's enough liquid to fill an Olympic-sized swimming pool in less than 15 minutes.


Amateur astronomer Jack Newton took this image of comet Lulin in early February 2009

'The comet is releasing a great amount of gas, which makes it an ideal target for X-ray observations,' said Andrew Read, from Leicester University.

The story of Lulin begins in 1996 when a seven-year-old boy in China bent over the eyepiece of a telescope and saw something that would change his life - a comet.

At first he thought he had discovered it, but soon learned that two men named 'Hale' and 'Bopp' had beat him to it.

Mastering his disappointment, young Quanzhi Ye resolved to find his own one one day.

In 2007, Ye discovered a comet when he was a student of meteorology at China's Sun Yat-sen University.

He spotted it in a photo taken nights before by Taiwanese astronomer Chi Sheng Lin on 'sky patrol' at the Lulin Observatory.

'It is a green beauty that could become visible to the naked eye any day now,' said Mr Ye.


The Swift satellite has detected a hydroxyl cloud spanning nearly 250,000 miles around the comet

He said: 'My retired eyes still cannot see the brightening comet,but my 14-inch telescope picked it up quite nicely on February 1.'

Current estimates peg the maximum brightness at 4th or 5th magnitude, which means dark country skies would be required to see it.

No-one can say for sure, however, because this appears to be Lulin's first visit to the inner solar system and its first exposure to intense sunlight.

Surprises are possible.

Lulin's green color comes from the gases that make up its Jupiter-sized atmosphere.

Jets spewing from the comet's nucleus contain cyanogen and diatomic carbon. Both substances glow green when illuminated by sunlight in the near-vacuum of space.

To see Comet Lulin with your own eyes, set your alarm for 1 am when the comet will be highest in the sky. It will be visible due south near Saturn, moving towards the west as dawn approaches.

British astronomers from Leicester University will study the comet using the NASA Swift Satellite to find out more about its chemistry and gather clues about the origin of comets and the solar system.

Source: http://www.dailymail.co.uk/sciencetech/article-1152682/Stargazers-treat-green-comet-size-Jupiter-streaks-past-Earth.html