A New Fuzzy Visitor to our Skies.

Discovered in July 2007, and known officially as C/2007 N3 (Comet Lulin) is an interesting visitor to our skies this month. It was discovered by a 19-year old university student in China on a photograph taken at Taiwan’s Lulin Observatory. It is easily visible in binoculars and certainly over the last few nights I have been able to see it the unaided eye. It is the only fuzzy object in the area. In a telescope, it looks a bit like a sword with a long dim tail and a smaller dim anti tail. In photographs it has a green tinge to it. In a pair of 10 x 50 binoculars it looks like a large fuzzy ball.

Comets are often referred to as "dirty snowballs." They are left over from the formation of stars and planets billions of years ago. They live in an area of space outside the orbit of Pluto called the Oort cloud. Usually made of chunks of frozen gases, ice and rocks and although some may be a few hundred kilometres across most are no more than a kilometre across. Every now and again one of these snowballs gets disturbed in its orbit and fall in towards the Sun.

As they get closer to the Sun, they start to heat up. The ice transforms directly from a solid to a gas and releases dust particles which were embedded inside the ice.

Sunlight and the stream of charged particles flowing from the sun – the solar wind – sweeps the evaporated material and dust back in a long tail. The comet's ingredients determine the types and number of tails.

Lulin’s closest approach to Earth, 0.41 astronomical units or 61 million kilometres (an astronomical unit is the distance from earth to the Sun- approximately 150 million kms) will occur on February 24th, when the comet should be at its peak brightness. At this time the comet will pass really close to Saturn in the sky. In fact, they will both be within the same binocular field of view field of view. Saturn is about 3 hand spans above the north-eastern horizon at around 10pm and nearly halfway between the bright stars Regulus and Spica. It looks distinctly yellow in colour and this should make it easier to spot.


This will be no replay of Comet McNaught from January 2007 but should still be bright enough that most of us can see it as a fuzzy ball in the sky and certainly worth the effort of having a look with binoculars if you do not have a telescope.

On the night of February 25th the comet goes through opposition, nearly 180° from the Sun in our sky. There is always the possibility of seeing some interesting effects with the tail and brightness when it goes through opposition.

After that Lulin moves away from both Earth and the Sun, so it will tend to fade quickly. The evening of February 27 will see it at about 6th magnitude within 1° of Regulus which is the brightest star in the constellation of Leo. Leo looks like an upside question mark to those of down under – rather than a roaring lion.

Unfortunately, if you miss it this time around, Comet Lulin won’t be returning again to the inner solar system for more than a thousand years.
Happy comet hunting!

Also, and a lot easier to see on February 28, you can see the crescent moon close to Venus, just a hand span above the western horizon half an hour after sunset. Venus looks great in binoculars at present. This is one of the last good opportunities for viewing this year in the evening.