Perseids
Just came in from the porch, where I was watching for Perseid meteors.
The Perseids are prolific meteor showers associated with the comet Swift-Tuttle, so-called because the point they appear to come from, called the radiant, lies in the constellation Perseus. The name derives in part from the word Perseides (Περσείδες), a term found in Greek mythology referring to the descendants of Perseus. The stream of debris is called the Perseid cloud and stretches along the orbit of the comet Swift-Tuttle. The cloud consists of particles ejected by the comet as it travels on its 130-year orbit. Most of the dust in the cloud today is around a thousand years old. However, there is also a relatively young filament of dust in the stream that was pulled off the comet in 1862. The rate of meteors originating from this filament is much higher than for the older part of the stream. The Perseid meteor shower has been observed for about 2000 years, with the earliest information on this meteor shower coming from the Far East. Some Catholics refer to the Perseids as the "tears of St. Lawrence", since 10 August is the date of that saint's martyrdom. The shower is visible around mid-July each year, with the peak in activity being around August 9-14, depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour. They can be seen all across the sky, but because of the path of Swift-Tuttle's orbit, Perseids are primarily visible in the northern hemisphere. As with all meteor showers, the rate is greatest in the pre-dawn hours, since the side of the Earth nearest to turning into the sun scoops up more meteors as the Earth moves through space. In 2009, the estimated peak Zenithal Hourly Rate was 173, but fainter meteors were washed out by a waning gibbous Moon.
Anyway, so I sat out there and watched what I could see of the sky from my porch. Trees block the view to some extent toward the south, while the floor of the porch of the apartment directly above mine blocks that directly above me, the wall separating my porch to the one directly north of mine cuts off the view there, and, of course, my apartment building blocks the view west of me. Assorted trees, buildings, and so on make the view even in favored directions less than ideal, but there's more than enough sky visible to catch a glimpse of Perseids, as the meteors from that particular shower can be seen in all parts of the sky, anywhere on Earth.
I did see some. They were all thin, bright streaks, very transient events that were over almost as quickly as they had begun, but their brightness and length were enough to register even with my not-so-good eyesight. No match for to the spectacular the Great Daylight Fireball of 1972, I'm afraid, but clearly meteors, and lively as the Perseids usually are. Starting right now and going on until dawn is a good time to see them, so if you're reading this, at least go to a window where you can clearly see the sky, or, better still, put on a sweater and go outside and look up. You're bound to see them about now if your area isn't covered in clouds (or, since this is Summer, after all, smoke from wildfires).
The Perseids are prolific meteor showers associated with the comet Swift-Tuttle, so-called because the point they appear to come from, called the radiant, lies in the constellation Perseus. The name derives in part from the word Perseides (Περσείδες), a term found in Greek mythology referring to the descendants of Perseus. The stream of debris is called the Perseid cloud and stretches along the orbit of the comet Swift-Tuttle. The cloud consists of particles ejected by the comet as it travels on its 130-year orbit. Most of the dust in the cloud today is around a thousand years old. However, there is also a relatively young filament of dust in the stream that was pulled off the comet in 1862. The rate of meteors originating from this filament is much higher than for the older part of the stream. The Perseid meteor shower has been observed for about 2000 years, with the earliest information on this meteor shower coming from the Far East. Some Catholics refer to the Perseids as the "tears of St. Lawrence", since 10 August is the date of that saint's martyrdom. The shower is visible around mid-July each year, with the peak in activity being around August 9-14, depending on the particular location of the stream. During the peak, the rate of meteors reaches 60 or more per hour. They can be seen all across the sky, but because of the path of Swift-Tuttle's orbit, Perseids are primarily visible in the northern hemisphere. As with all meteor showers, the rate is greatest in the pre-dawn hours, since the side of the Earth nearest to turning into the sun scoops up more meteors as the Earth moves through space. In 2009, the estimated peak Zenithal Hourly Rate was 173, but fainter meteors were washed out by a waning gibbous Moon.
Anyway, so I sat out there and watched what I could see of the sky from my porch. Trees block the view to some extent toward the south, while the floor of the porch of the apartment directly above mine blocks that directly above me, the wall separating my porch to the one directly north of mine cuts off the view there, and, of course, my apartment building blocks the view west of me. Assorted trees, buildings, and so on make the view even in favored directions less than ideal, but there's more than enough sky visible to catch a glimpse of Perseids, as the meteors from that particular shower can be seen in all parts of the sky, anywhere on Earth.
I did see some. They were all thin, bright streaks, very transient events that were over almost as quickly as they had begun, but their brightness and length were enough to register even with my not-so-good eyesight. No match for to the spectacular the Great Daylight Fireball of 1972, I'm afraid, but clearly meteors, and lively as the Perseids usually are. Starting right now and going on until dawn is a good time to see them, so if you're reading this, at least go to a window where you can clearly see the sky, or, better still, put on a sweater and go outside and look up. You're bound to see them about now if your area isn't covered in clouds (or, since this is Summer, after all, smoke from wildfires).