Rare blue moon, Orionids meteor this month

Published October 1, 2020, 4:36 PM

by Ellalyn De Vera-Ruiz

Meteor showers and a Halloween blue moon are on their way to dazzle the night skies this month.

According to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), the Orionid meteor shower will be active from Oct. 17 to 25.

At maximum rates, the shower may reach 15 meteors per hour that may be observed at favorable sky conditions, but sometimes there are lulls even during the usual Oct. 21-22 maximum peak nights.

The Orionids meteor shower is a result of the earth passing through the debris trail left by Halley’s comet, PAGASA said.

The weather bureau also noted the occurrence of two full moons this month, on Oct. 2 and Oct. 31.

“For more than half a century, whenever two full moons appear in a single month, which happens on average every two and a half to three years, the second full moon is called a blue moon,” PAGASA explained.

“Since the lunar cycle is 29 days and most months have 30 to 31 days, we eventually find a situation where a full moon occurs at the beginning and the ending of the same month,” it added.

It pointed out that the phrase blue moon has nothing to do with the actual color of the moon.

PAGASA, however, said there are times that the moon appears tinged with blue colors due to certain atmospheric conditions, such as those caused by volcanic eruptions or by exceptionally large fires that leave particles in the atmosphere. 

Skygazers can also see other noteworthy events this month.

The Square of Pegasus, an asterism of the constellation of Andromeda, will take center stage in the Philippine night sky after sunset, which is a sign of the arrival of the northern fall, PAGASA said. 

The agency noted that northeast of it lies the Andromeda galaxy, the closest large spiral galaxy to the Milky Way galaxy. Under clear skies, with the aid of a star map and familiarity with the surrounding background stars, it can be seen as an elongated misty patch with the naked eye and can be easily viewed through binoculars and telescopes, PAGASA said.