Moon to spoil meteor show
PARIS — A bright moon will outshine the annual Perseids meteor shower, which will peak Saturday with only one-fifth the usual number of shooting stars visible from Earth, astronomers said.
The light from the waxing gibbous moon will spoil stargazers’ view in a similar way to that of urban light pollution.
“To be honest, it’s not a good year” for the Perseids, said Robert Massey, acting executive director of the Royal Astronomical Society in London.
“You might, if you’re lucky, see maybe 20 an hour,” he said.
The Perseids happen when Earth hits a belt of debris left behind by the comet Swift-Tuttle on its elongated, 133-year orbit around the Sun.
Each shooting star is a piece of comet dust, burning up from friction as it hits Earth’s atmosphere.
Normally, Northern Hemisphere viewers are treated to a spectacle of about 100 to 120 visible shooting stars per hour when the phenomenon peaks around mid-August — depending on the moon and the weather.
Last year, there was an unusual “outburst” with more than double the usual fireball activity as Earth passed through especially dense “ribbons” of debris within the comet’s dust belt.
“This year, we are expecting enhanced rates of about 150 (meteors) per hour or so, but the increased number will be canceled out by the bright moon, the light of which will wash out the fainter Perseids,” said a NASA blog.
The moon was full on Monday, and will have waned to approximately 80 percent illumination by Saturday.
Not all is lost
“This is not much better than a full moon and will certainly pose a challenge in viewing the Perseids this year,” said the International Meteor Organization.
This means it would make little difference if you sought out a rural area with little artificial light pollution — conditions usually recommended for meteor watching.
The experts advised trying to catch a glimpse before the moon rises around 11 pm on Friday.