Stargazers are in for an amazing celestial display tonight,
as the Perseid meteor shower will light up the night sky in what has been
predicted to be a spectacular event. According to NASA, we should be able to
see meteors every couple of minutes during the dark hours before Tuesday,
August 12.
The Perseid meteor shower occurs when the Earth passes
through a meteor stream, and in this case, the origin of the meteors is the
comet Swift-Tuttle. In the comet’s passage by the Sun, it ejects particles that
form the Perseid cloud – the tail of the comet.
The comet was discovered almost 150 years ago. It takes 133
years for it to complete the orbit around the Sun. In 1992, the comet created
the most spectacular meteor shower in recent history, with four times the
average number of meteors.
The Perseid meteor shower is known to regularly occur ever
year in mid-summer, while reaching a peak in the first half of August, when the
chances are to see tens of meteors in a matter of minutes. The meteors are
known as Perseids because they appear to come from the constellation Perseus.
Despite its highly known regularity, the Perseids failed to
appear for the first time in 2000. According to the International Meteor
Organization, the Perseids were much more dynamic in the 1990s, with rates
decreasing after 2000.
This year, “the time to look is during the dark hours before
dawn on Tuesday, August 12th,” as Bill Cooke from NASA's Meteoroid Environment
Office at the Marshall Space Flight Center explained. “There should be plenty
of meteors--perhaps one or two every minute.”
The comet Swift-Tuttle is currently positioned at an impressive
distance, beyond the orbit of Uranus, but the trail it leaves behind stretches
all the way back to Earth. The specks of comet dust will hit Earth’s atmosphere
at 132,000 mph. At this speed, even a flimsy speck of dust creates a vivid
streak of light as it disintegrates upon entering the atmosphere, NASA
explained. These incandescent particles are known as meteors.
“Earthgrazers are long, slow and colorful,” explained Cook, also
adding that “they are the most beautiful of meteors.” And even though the sky
will not necessarily be shattered by Perseids at all times, seeing just a few
of them will make the wait worthwhile.
Cook explained that in the night between August 11 and August
12, the light of the gibbous Moon will interfere with the meteor shower for a
short period of time. However, after 2 a.m. Tuesday morning, the Perseids will
become visible once more. Hundreds of meteors are expected to light up the sky
by dawn.
The Perseid meteor shower may be the most visible meteor
shower we witness, but it’s not necessarily the most spectacular. Once ever 33
years, the Leonids meteor shower, also known as the King of Meteor Showers,
produces the so-called meteor storms, with hundreds of thousands of meteors per
hour.
In addition to the visually-observable showers, there are
still many other weakly active ones throughout the year, usually observed by
still-imaging, video, radar or telescopic observations can identify, the
International Meteor Organization informs.