While Americans associate fireworks with the first weekend in July, with their July 4th Independence Day celebration, those of us into skywatching get our shows throughout the latter half of July, with several showers reaching their peaks in the last week of the month.
As long time readers already know, meteor showers are the specks of sand and bits of gravel left over from outgassings on comets. Some of those have been documented in modern history. Most, however, have been running for tens of thousands of years, and a handful may be nearly a hundred thousand years old.
There are a lot of meteor showers in July, and they go through building periods and waning periods. They’re named after the closest star in the sky the streams seem to be radiating from – in effect, the part of the sky where the tangent of their orbital velocity is directly perpendicular to the Earth.
We’re past just past the peak of the July Phoenicids. However, there are a number of meteor showers picking up that started earlier in the month such as the Alpha Pisces Australids (which tend to be few streaks, but a few bright ones) and the gem of the southern skies in July, the Southern Delta Aquarids, which hit their peak around July 28th to 30th, and first started sparking on the 14th. They taper off rapidly from their peak around August 3rd.
We are particularly fortunate in the timing of the Southern Delta Aquarids, because they’re very near the night of the new moon; this keeps moonlight from washing out your vision as you stare into the skies.
Starting roughly a week later, and lasting longer, are the Alpha Capricornids, about 30 degrees counterclockwise on the sky. They’re likely to hit their peak about August 2nd or 3rd, and when they peak, they tend to create a lot of streaks of color across the sky arcing out from their radiant. (One reason why the Alpha Capricornids tend to peak “off center” of their visibility is the angle that they intersect the earth’s orbit at; they sort of brush across the Earth’s orbit and “ride with us” for a bit through the densest part of the storm.
To prepare for watching meteor showers, we recommend taking a nap in the afternoon. Besides, it’s a great justification for the missus. “I’m not being lazy – this is for science!”. Once you’re up, dim the lights – and make a red filtered flashlight to find your way outside. It will take a good 20-30 minutes for your eyes to fully dark adapt.
Then sit back, get comfortable and enjoy the show, taking plenty of time to see the meteors as they become visible in bursts of activity.
Ian Maclean – Author, Presenter, Astronomer and Science Show host.
You can discover the hidden secrets of the night sky
the fun and easy way for yourself at http://www.nightskysecrets.com, plus pick up a fr*ee subscription to the RSS podcasts of my weekly radio show
The Science Hour or simply listen to them online at
http://www.askthescienceguru.com
As long time readers already know, meteor showers are the specks of sand and bits of gravel left over from outgassings on comets. Some of those have been documented in modern history. Most, however, have been running for tens of thousands of years, and a handful may be nearly a hundred thousand years old.There are a lot of meteor showers in July, and they go through building periods and waning periods. They’re named after the closest star in the sky the streams seem to be radiating from – in effect, the part of the sky where the tangent of their orbital velocity is directly perpendicular to the Earth.
We’re past just past the peak of the July Phoenicids. However, there are a number of meteor showers picking up that started earlier in the month such as the Alpha Pisces Australids (which tend to be few streaks, but a few bright ones) and the gem of the southern skies in July, the Southern Delta Aquarids, which hit their peak around July 28th to 30th, and first started sparking on the 14th. They taper off rapidly from their peak around August 3rd.
We are particularly fortunate in the timing of the Southern Delta Aquarids, because they’re very near the night of the new moon; this keeps moonlight from washing out your vision as you stare into the skies.
Starting roughly a week later, and lasting longer, are the Alpha Capricornids, about 30 degrees counterclockwise on the sky. They’re likely to hit their peak about August 2nd or 3rd, and when they peak, they tend to create a lot of streaks of color across the sky arcing out from their radiant. (One reason why the Alpha Capricornids tend to peak “off center” of their visibility is the angle that they intersect the earth’s orbit at; they sort of brush across the Earth’s orbit and “ride with us” for a bit through the densest part of the storm.
To prepare for watching meteor showers, we recommend taking a nap in the afternoon. Besides, it’s a great justification for the missus. “I’m not being lazy – this is for science!”. Once you’re up, dim the lights – and make a red filtered flashlight to find your way outside. It will take a good 20-30 minutes for your eyes to fully dark adapt.
Then sit back, get comfortable and enjoy the show, taking plenty of time to see the meteors as they become visible in bursts of activity.
Ian Maclean – Author, Presenter, Astronomer and Science Show host.
You can discover the hidden secrets of the night sky
the fun and easy way for yourself at http://www.nightskysecrets.com, plus pick up a fr*ee subscription to the RSS podcasts of my weekly radio show
The Science Hour or simply listen to them online at
http://www.askthescienceguru.com
