In a dark sky with lots of stars visible, the constellation's points can be connected to form a convincing Big Dog profile. ■ Sirius the Dog Star blazes in the southeast after dinnertime, below Orion. It should be down to 7.5 by February 17th. And of course the comet's light is much more spread out ("diffuse"). By then it will probably be about mag 6.4, which is some 300 times fainter than Mars. On the evenings of February 10th and 11th the comet will be less than 2° from bright Mars. When the comet becomes too faint for that chart to suffice, use the more detailed one in the February Sky & Telescope, page 48 (where the dates are for 0:00 UT subtract one day from those to get the North American civil date).
(On that chart, the comet symbols are labeled with the dates for evenings in North America, not the UT dates.) Bob King's new article Understanding the Tails of Comet ZTF has a finder chart to use in February. The comet is heading south after its swing past the Little Dipper in late January. Don't confuse long-exposure, stacked and processed images of a dim, diffuse object like this with its appearance to the eye, even in the same telescope! Note the narrow, straight ion tail and the broad, curved dust tail. Comet ZTF E3, imaged on January 21st by Pepe Chambó of Valencia, Spain, using an 8-inch short-focus reflector. That evening, using 10 x 50 binoculars under a mediocre suburban sky, I could just detect it near Iota Aurigae as a vague, diffuse enhancement of the sky background. As of February 9th it was down to about 6.1. It peaked in brightness on February 1st at about magnitude 5.0. The comet is crossing Auriga and Taurus on its way toward Orion's shield.
On the other hand, it's now conveniently placed high overhead in early evening in a moonless sky the waning Moon doesn't rise until late. Comet ZTF is fading and receding into the distance.
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