A fantastic, one-of-a-kind celestial happening will occur on Tuesday, October 23rd, as Comet 168P/Hergenrother and Comet C/2012 J1 (Catalina) will pass each other in space like ships in the night—but only during a very narrow viewing window. Slooh Space Camera will provide live coverage of this spectacular event on Tuesday, October 23rd, live on Slooh.com, free to the public starting at 2 p.m. PDT / 5 p.m. EDT / 21:00 UTC—accompanied by real-time discussions with Slooh President Patrick Paolucci, Slooh Outreach Coordinator Paul Cox, and Astronomy Magazine columnist Bob Berman. Viewers can watch live on their PC or iOS/Android mobile device.
Slooh was first alerted to this unusual event by long-time Slooh member Maynard Pittendreig; he and other members have been tracking both comets. The comets will appear close in the sky to fall within the reach of a single field-of-view of Slooh's robotic telescopes. The pair will have an apparent separation of 43.5 arcminutes, as shown in this sky chart: goo.gl/hq8hK
Comet 168P/Hergenrother has been through a number of "outbursts" over the last 6-weeks. Each of these unexpected increases in brightness has been witnessed and actively imaged by Slooh members. The outbursts could be a sign that the comet nucleus is starting to break apart, which is why the comet is being observed every night by Slooh members.
Comet C/2012 J1 (Catalina) has been a superb contrast to Hergenrother; exhibiting a far more stable and expected increase in brightness as it orbits the Sun. Both comets have shown relatively bright comas and small tails.
Astronomy Magazine's Bob Berman says, "It's comet fiesta time for astronomers—and the public. Here Slooh will simultaneously watch two comets as they dramatically zoom in opposite directions in the same field of view! Next year at this time, Comet ISON should become a naked-eye wonder. And a few months after that, the Rosetta Mission has its rendezvous—and eventual landing on—yet another comet. Edmund Halley's ghost is probably smiling."
Comet 168P/Hergenrother was originally discovered by Carl W. Hergenrother on 22 November 1998. A periodic comet, it has an orbital period of 6.923 years. It last reached perihelion (its closest approach to the Sun) on 1 October 2012.
Comet C/2012 J1 (Catalina) was discovered by A. R. Gibbs of the Catalina Sky Survey on 13 May 2012. The CSS is a prolific comet discoverer as it searches for near-Earth objects as part of its government mandate. Classified as a "hyperbolic comet", C/2012 J1 won't return to the inner solar system within the next 200-years. It will continue to brighten as it reaches perihelion on 7 December 2012.
Explore further: Asteroid 2012 TC4 to buzz Earth on October 12