Normally, comets are named after their discoverers (witness Levy-Shoemaker 9 or Hale-Bopp). In the case of Comet Lulin, it is named not after its discoverer but the observatory that took the images; Lulin Observatory in Taiwan (it was actually discovered in 2007 in a series of images by student Quanzhi Ye, a student at Sun Yat-sen University, who was participating in an asteroid survey). This visitor, which literally hails from the depths of space, appears to be making its first visit into the inner Solar System. These comets are of prime interest to astronomers, as they contain material that is essentially pristine and has been preserved for perhaps billions of years. In essence, they provide us a glimpse into the early days of our Solar System.
In the case of Comet Lulin, we have one here that is on such a trajectory that it will pay a brief visit to the inner Solar System (it already had its close encounter with the Sun on the 14th of January) and exit back into deep space, and it's on a no return trajectory. In short, this one probably won't be coming back, at least for tens of millions of years.
As it zips through the Solar System, though, it appears to be heading straight towards us. Considering the tremendous distances in interplanetary space, looks can be deceiving. At its closest, it will pass around 38 million miles (61.2 million kilometers) on the 24th of February, a little more than the distance to the planet Venus.
All of this data is interesting, but for the average person, the bigger question remains - will we be able to see it? Yes, though don't expect a spectacle here. More than likely, even under dark skies, Comet Lulin will be a daunting target, though it will be visible through binoculars and telescopes as a small, fuzzy star. Much talk has been made of the "double tail" that this comet will be producing. This is an illusion, caused by the comet's motion towards us, producing a "spike tail" that appears to be ahead of the comet. What you actually have are two tails, one composed of dust and the other ionized gas. The dust tail is composed of solids, dust, that are being lifted from the surface of the comet. This dust trail has particles that travel at a slower speed compared to the heated gas that composes the ion tail; this tail points almost exactly opposite the Sun. When viewed from above, the tails point in a "V", especially in comets traveling at high speeds. From our perspective here on Earth, it appears as though they are pointed in opposite directions.
Where will Comet Lulin be in the next few weeks? On the 1st of February, it can be found in the morning sky near Libra and the star Zebenelgenubi, but it will begin to move west in our skies until it approaches Saturn and Leo, and moves into the evening sky. On the evening of its closest approach, the 24th of February, it will be just south of Saturn, and it may be possible to view both in the same telescopic view. But that encounter is just one many on its journey. To make finding Comet Lulin easier, below is a list of all the encounters Comet Lulin will have with easy to find objects. The chart also has them labeled.
1 February – East of Zebenelgenubi
16 February – North of Spica
24 February – South of Saturn
1 March – West of Regulus
6 March – South of M44 (Praesepe/Beehive Cluster)
1 April – Between the twins in Gemini
Its speed will be amazing as it moves along from night to night. After that, it will fade away over the weeks until it disappears into the depths, heading into the infinite cold of the outer Solar System and beyond.
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