Newly discovered comet visible in morning sky

A recently discovered comet is surprising skywatchers by becoming brighter than predictions had first suggested and can now be seen with the unaided eye during the next few weeks.

Comet McNaught, officially catalogued as C/2009 R1, was discovered by Australian astronomer Robert McNaught last September using the using the 0.5-meter Uppsala Schmidt telescope and a CCD camera. It’s the 51st comet that bears McNaught’s name.

Although initially an extremely faint object, enough observations of the newfound comet were made to allow Brian Marsden of the Smithsonian Astrophysical Observatory in Cambridge, Mass., to calculate an orbit.

Comet McNaught is expected to pass closest to the sun (perihelion) on July 2, at a distance of 37 million miles (60 million km). The sky map shows where to look in order to spot the comet in the morning sky. (SkyMap below)

The comet is visible now for people with dark skies away from urban and suburban lighting. By mid-June it may be an easy skywatching target for most people.

Comets brighten when the get nearer to the sun, because solar radiation boils icy particles and dust off the comet’s nucleus. A cloud of material called a head, or coma, and sometimes a tail form. It’s all illuminated by reflected sunlight.

The most recent “reliable” observation was made by Alexandre Amorim of Florianopolis,Brazil who saw the comet on June 6 using 10×50 binoculars and estimated the magnitude as +5.5. That’s about as bright as the faintest star in the bowl of the Little Dipper (on this scale, smaller numbers represent brighter objects). In the coming days, the comet is expected to continue to brighten as it gets closer to the sun.

If you want to get a view of the comet, you’ll have to get up early in the morning. Set your alarm clock for at least two hours before sunrise. For most people that will mean around 3:30 a.m. local time. The comet is currently moving through the constellation of Perseus, the Hero, which at that early hour will be low in the northeast part of the sky.

The comet will pass to the south of the second magnitude star, Mirfak around June 14. Both star and comet will be about 20-degrees above the northeast horizon (10-degrees is roughly equal to the width of your clenched fist held at arm’s length; so the comet will be about “two fists” up from the horizon). Don’t expect anything spectacular just yet, however.

The comet should appear as a dim and diffuse, circular patch of light. Binoculars or a small telescope will help to bring it out better; you might even make out a faint greenish color.