For a quick overview: The emerging info on the Comet Lulin , newly discovered in July 2007, is now attracting interest outside the astronomical circle. This is one big comet, with an atmosphere allegedly three times the size of the planet Jupiter. Featuring two tails (a tail and an anti-tail), Comet Lulin is a 'green comet' (which means it is issuing poisonous gases, a circumstance sometimes seen in comets), with enough internal energy or forces to quickly replace one of the tails it recently lost...and it is traveling backward.
The following is, shall we say, a stimulating list of tidbits (so far known) on the backward traveling Comet Lulin:
--On February 11 (Our Lady of Lourdes; 151st anniversary of the Virgin's first apparition to St. Bernadette): Currently creeping westward at 2° per day, Comet Lulin will, by February 11, cross into Virgo and pass within a quarter degree of Lambda Virginis. (Catholics the world over might consider that fact a somewhat startling coincidence.)
--The Backward Comet: Comet Lulin is traveling along the same 'plane' as Earth (almost exactly along the ecliptic) — but, as previously noted, it is traveling backward. The comet's nearly parabolic orbit indicates that it has never interacted with our system's planets. Currently, Lulin's orbital inclination is 178.4°, meaning that it is orbiting in the opposite direction from the planets just 1.6° from the ecliptic plane. (In the vastness of space...that's close; very close to Earth.)
--If, as astronomers are currently alleging, Comet Lulin passes through earth's plane every 1,000 years, where is it recorded on ancient star charts? So far, not one contemporary astronomer has openly made reference to ancient star charts - a very interesting oversight. Rather, astronomers are theorizing that this is Lulin's first pass by our sun, with the result that the comet is still encrusted in 'fresh' ices, preserved by the freezing environment of the outer solar system.
--Break Up Possibilities? As Comet Lulin is exposed to the sun's heat for the first time, astronomers conjecture that those ices will vaporize, possibly causing the comet to brighten rapidly or even break apart. Considering the comet's size and its unusual orbit, the degree to which it loses 'chunks' or breaks apart is unforeseeable. (Picture to the right from New Mexico, USA.)
--How predictable is Comet Lulin? The comet's brightness behavior may be unpredictable, because (again) it's on a near-parabolic orbit, (again) suggesting this may be its first visit to the inner solar system. More than how bright the comet shall become, there are other serious considerations (like those mentioned in the paragraph above). As one commentator quipped, "You never know what a pristine comet might do."
--Comet Lulin is definitely in the neighborhood. Comet Lulin - 2007N3 will approach to 0.41 AU -which, from Earth, is only about 38 million miles away. (Once more, that is very close to our "Terra.") Consider and compare: The sun is 93 million miles away from Earth. At closest approach to earth, Comet Holmes was 149 million miles.
--Those two tails. Because Comet Lulin stays nearly on the ecliptic, its tail (which points away from the Sun) aligns with the ecliptic and with the comet's own direction of motion across the sky. The comet is within Earth' plane, so (from our viewpoint) we're likely to see the comet with a very thin tail and an "anti-tail," a spike pointing in almost the opposite direction from the main tail, for months on end. As of January 7th, Comet Lulin did have an "anti-tail." A few rare but recent reports say this tail broke off around February 5th - only to be soon replaced by a new, emerging anti-tail.
--On the Eve of Ash Wednesday: Comet Lulin’s closest approach to Earth, 0.41 a.u. (61 million km), occurs on February 24th, when the comet may reach a peak of magnitude 5°. At this time, it should be visible in late evening (after rising around the end of astronomical twilight) and remains in view for the rest of the night. And it's speeding along at just over 5° per day!
--From where did Comet Lulin come? Comet Lulin is arriving from the far reaches of the solar system on a nearly parabolic orbit — "it's almost as if it comes from infinity and goes back out to infinity," said Mark Hammergren of Chicago's Adler Planetarium.
That last remark can only make one think of God, Our Lord - the Alpha and the Omega, He who has no beginning and no end...in other words, Infinity Himself.
More tidbits on Comet Lulin coming up soon!