In a six-month stretch during which one comet unexpectedly went poof and a second miraculously survived a solar swingby, it's nice to know that Comet Garradd (C/2009 P1) has continued its leisurely swing through the inner solar system.
Perihelion came and went on December 23rd at a point 1½ astronomical units (145 million miles) from Sun and far above the planetary plane. But in the weeks since, owing to its high orbital inclination, the comet has moved closer to Earth. It's remained reasonably bright, somewhere near 7th magnitude, which makes it an inviting target for binocular and small-telescope users.
Back in November, Comet Garradd made a sharp turn and headed up through Hercules. A few days ago, it slipped less than 1° to the west of the superb globular cluster Messier 92 in Hercules — a close encounter that didn't go unnoticed by astrophotographers.
The view above, captured by Rolando Ligustri using a remotely operated telescope in New Mexico, captures the pairing beautifully. The comet's faintly blue gas tail extends about 2° toward upper right, while a more compact dust tail points toward the cluster. Ligustri recommends that you download the full-size image "to appreciate the details of M92 and the incredible number of small galaxies in the image."
Few of us have access to remote-controlled telescopes under pitch-dark skies, so what For the next week or so, a nearly full Moon is going to subdue Comet Garradd's luster. But after that the prospects couldn't be better for northern observers. It's picking up steam as it heads even farther north and becomes circumpolar for those in the U.S., Europe, and at comparable latitudes.
Use the chart above (and the larger versions here) to find it high in the eastern sky before dawn. In mid-February it passes near the head of Draco and continues along the arc of stars marking the Dragon's back. Throughout all of this, the visitor should remain near 7th magnitude — hardly naked-eye bright, but then again something you should be able to pick up even with modest optical aid.
By early March, when Comet Garradd comes closest to Earth, it'll be poised over the Big Dipper's bowl and perched well above the horizon as soon as the evening sky gets good and dark. Will we still be enjoying good views of it a month from now? Check back here in a few weeks for an update! In the meantime, feel free to share your impressions of its appearance in the comments section below.