Comet Lulin passes near the Earth on February 23, 2009 at the same time that it appears to pass 2 degrees south of Saturn.
I first observed comet Lulin August 3, 2008 as it passed 2 degrees north of Jupiter. This comet appears to pass so close to the planets because comet Lulin is closely aligned with the ecliptic, the Sun & planets path through the sky.
Although the rule of thumb is that comet tails point away from the Sun, a comet aligned with the ecliptic with an angular distance from the Sun that is increasing, can display an anti-tail that appears to point toward the Sun.
This is because the dust tail, although it initially points away from the Sun, curves as it is spread out along the orbit of the comet as it recedes from the Sun. At the same time the gas tail can be seen pointing directly away from the Sun.
I took this photo on the morning of February 1, 2009 with my 4.5" scope. The dusty anti-tail points to the upper left, the gas tail can be seen to the lower right.
I first observed comet Lulin August 3, 2008 as it passed 2 degrees north of Jupiter. This comet appears to pass so close to the planets because comet Lulin is closely aligned with the ecliptic, the Sun & planets path through the sky.
Although the rule of thumb is that comet tails point away from the Sun, a comet aligned with the ecliptic with an angular distance from the Sun that is increasing, can display an anti-tail that appears to point toward the Sun.
This is because the dust tail, although it initially points away from the Sun, curves as it is spread out along the orbit of the comet as it recedes from the Sun. At the same time the gas tail can be seen pointing directly away from the Sun.
I took this photo on the morning of February 1, 2009 with my 4.5" scope. The dusty anti-tail points to the upper left, the gas tail can be seen to the lower right.
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