'DAYTIME COMET' TO ARRIVE IN 2013

Skygazers are in for a treat when Comet Ison passes by the Earth later this year: it's expected to be so bright that it will outshine the moon and be visible even in broad daylight.

Filipino astronomer Frederic Gabriana calculated that Comet Ison will be seen in the Philippines by November.

Space.com was cited in an earlier report as saying that it might even be seen during the daytime on Nov. 28, 2013 —weather permitting, of course.

Officially known as Comet C/2012 S1, Ison was first discovered in September, 2012, by Russian astronomers Vitali Nevski and Artyom Novichonok at the International Scientific Optical Network (or "ISON," hence the name) near Kislovodsk.

The comet was first seen near the constellations of Gemini and Cancer.

"Comet Ison could draw millions out into the dark to witness what could be the brightest comet seen in many generations – brighter even than the full Moon," astronomer David Whitehouse said in an article on the UK's The Independent.

'Galactic litter'

Comets are icy rocks within the solar system that display a fuzzy atmosphere called a "coma," and a visible tail, especially when it comes closer to the Sun.

Comets are believed to be made up of ammonia, carbon dioxide, methane, and water.

Most of the comets are thought to be residents of Oort Cloud and Kuiper Belt, some 5,000 to 100,000 astronomical units (AU) away from the Earth (one AU = 150 million km).

"Occasionally, giant molecular clouds, stars passing nearby, or tidal interactions with the Milky Way's disc disturb the orbits of some of these bodies in the outer region of the Oort Cloud, causing the object to fall into the inner solar system as a so-called long-period comet," NASA said.

Comet Ison for one, is believed to be a castaway from Oort Cloud.

2013: A year of comets

But Ison seems not to be the only comet visiting the Earthlings this year.

"Another comet, called Comet 2011 L4 (PanSTARRS), was discovered last year and in March and April it could also be a magnificent object in the evening sky," Whitehouse wrote.

Comet 2011 L4, discovered in the constellation Libra on June 2011, may not shine as bright as Ison but will still be visible to the naked eye.

"The comet is expected to be brightest in February or March 2013, when it makes its closest approach to the sun. At that time, the comet is expected to be visible low in the western sky after sunset, but the bright twilight sky may make it difficult to view," University of Hawaii Institute of Astronomy said in a press release.

"2013 could be the year of the great comets," Whitehouse added.

One-time deal?

Whitehouse also said that Comet Ison "may never return."

"Its tail points outward now as the solar wind is at its back, and it fades and the comet falls quiet once more, this time forever," the astronomer concluded. — TJD, GMA News