Comet Lovejoy (C/2013 R1) reaches a pivotal point

Comet Lovejoy (C/2013 R1) reaches a pivotal point in its orbit next week when it comes closest to the sun.

It will still be visible to earthbound skygazers, astronomers say.

While not a sun-grazer like its sibling comet, ISON, which flew into the sun and vapourised last month, Lovejoy is expected to reach so-called perihelion on Christmas Day.

"When the comet comes close to the sun, the solar winds push material off of it," said Jin Koda, an assistant professor in the department of astronomy and physics at Stony Brook University.

Those winds force dust, ice and vapours off the core into the characteristic tail. Koda has captured some of the world's best photos of Lovejoy's journey.

Last week, the comet could be spotted near the Big Dipper's handle but it's moving at nearly 300 miles per second and can now be spotted near an entirely different star cluster-Hercules.

Experts recommend evening viewing because the moon may hinder a good sighting before dawn.

With a pair of binoculars Lovejoy should be easily visible around 6:30 p.m. EST until the end of the year.

"If you're looking east, the Big Dipper is scraping the horizon and its bowl is pointing on an angle up near the North Star," said comet tracker Dan Malerbo, an astronomer with the Buhl Planetarium and Observatory in Pittsburgh.

"Hercules is located to the left of the Big Dipper and has the shape of a keystone," he said.

"This comet isn't getting too close to the sun. ISON was about 700,000 miles from the sun. This one is 70 million miles away."

Image of Comet Lovejoy (C/2013 R1) captured by the Subaru Telescope's Suprime-Cam on December 3, 2013 (Hawaii Standard Time). 

The wavelength was at 450 nm (B-band), with a 180 second exposure. 

Credit: NAOJ, data processing by Masafumi Yagi (NAOJ)

A team of astronomers from Stony Brook University (the State University of New York at Stony Brook), the National Astronomical Observatory of Japan (NAOJ), and others used Suprime-Cam, Subaru Telescope's wide-field, prime-focus camera, to capture an image of the intricate flow of Comet Lovejoy's (C/2013 R1) ion tail.

The instrument's combination of a wide field of view and high spatial resolution provides a clear delineation of the complex, wiggling streams in the comet's tail.

At the time of this observation, at around 5:30 am on December 3, 2013 (Hawaii Standard Time), Comet Lovejoy was 50 million miles (80 million km) distant from Earth and 80 million miles (130 million km) away from the Sun.