August 4th, 2021
By A.J. Gentile
What are Meteor Showers?
Meteor showers are events that happen when the Earth revolving around the sun, passes through cosmic debris left by comets and asteroids. This is why it happens at the same time each year and why it seems like it is coming from the same position. This debris is entering Earth's atmosphere at very high speeds and some fragments that are small enough will burn up in our atmosphere creating shooting stars, while larger debris are known as meteoroids and they can make for very beautiful fireballs.
Meteor showers happen all year-round and are named after the quadrant of sky (namely the constellation) in which the meteors seem to be coming from. A perfect example of that is the Perseid Meteor Shower which originates from the direction of the constellation of Perseus.
There are multiple meteor showers per year and the three largest are those of The Quadrantids (approx. 110/hr), The Perseids (approx. 110/hr), and The Geminids (approx. 120/hr).
The number of viewed meteors depends on where we are and in which time of the year it is when we are enjoying the splendor of the show.
How to photograph meteor showers
A few things you need to know if you want to shoot meteor showers are the following:
- When will the meteor shower be at its highest level of activity?
- From what location, and from what direction should I be set up to capture the best resulting shower?
Fortunately, there are a multitude of websites and smart device applications that you can use to determine most of this needed information.
For smartphone and tablets, the most popular one are:
You can also use the following websites:
Also, you will need the right equipment to be able to capture great shots. First of all, you will need a camera that can shoot in manual mode and that is capable of a shutter speed of around 5-10 seconds. If your camera is not an interchangeable lens one, as a point & shoot one, you will need one that has a wide to ultra-wide angle lens. Speaking of lenses, you’ll need one that has a focal length between 16mm to 20mm. My preferred lens for shooting meteor showers is a 20mm f/1.8, but a zoom lens in the focal length of 16-35mm works well too.
How to find the radiant of the Meteor Shower
The radiant of the meteor shower is the direction from where the meteor shower is originating from. We label the radiant by the name of the constellation from where the meteor showers seem to be coming from.
What we use the radiant for is to know how to best place the camera in order to compose the best image to capture the meteor shower. Very much like when capturing star trails, the further you are away from the radiant, the longer the meteor trails will be in your image. Also, to be able to capture the most meteors passing over our heads, it is always better to use shorter focal lengths. Selecting an interesting foreground also adds immensely to the image we are composing.
For the astro photographers out there, here is the precise information we need to know in locating the radiant of the meteor shower. For those of us who don't need this precision, just look, find the constellation radiant direction and point your cameras in the general direction of the constellation and start shooting.
As you can see in the table above, the position of the radiant in the sky is defined by two coordinates: right ascension and declination.
The right ascension is the angular distance measured eastward along the celestial equator between the vernal equinox (or autumnal equinox in the Southern Hemisphere) and the celestial body. Together with the declination, it defines the position of a celestial body in the sky. It's measured in hours (1h equals to 15º), minutes and seconds.
The declination is the vertical angular distance between the center of a celestial body and the celestial equator. A declination of +20º means that the celestial body is located 20º north of the celestial equator. The south polar cap is at a declination of -90º, the equator is at declination 0º, and the north polar cap is at a declination of +90º. Declination is to a celestial globe as latitude is to a terrestrial globe, a vertical positioning of an object.
The Perseid Meteor Shower 2021: July 17th to August 24th
The Perseid Meteor shower is considered to be one of the best Meteor Showers of the year because of the zenithal hourly rate (ZHR) of (on average) above 110 meteors/h, the night of the peak is usually spectacular.
The actual time for the Perseid Meteor shower starts on July 17th and ends on August 24th, but in 2021 the meteor shower will be at its peak on the evening between August 12th at 3:51am and the Moon will only be at 16%. As a backup, the morning of the 13th at 3:51am will also be a possibility, except that the Moon will be a 25% and so may wash out the meteor shower a little.
Perseid Meteor Shower Highlights:
- When: July 17 to August 24, 2021
- Best night: August 11-12
- Peak: August 12 at 3:51 am EDT
- Moon phase: 16.0% (good viewing conditions)
- Number (ZHR): 85.2 meteors/h
- Meteors velocity: 59 km/s
- Origin (radiant): Perseus constellation
- Radiant coordinates: Right ascension 03h 12m, declination +58.0º
- Associated comet: 109P/Swift-Tuttle (discovered in 1862)
- Northern Hemisphere: High rate
- Southern Hemisphere: High rate
You now have everything you need to catch a shower of shooting stars. Be patient, have a good coffee and don't forget to make a wish!