This article details my experience capturing the Perseid Meteor shower photo over Mount Rainier, which was published by NASA for their Astronomy Picture of the Day on August 25th, 2015.
The 2015 Perseid meteor shower peaked before dawn on Thursday August 13, and what a show it was! With the moon out of the sky very faint meteors could easily be seen from locations away from city lights. The Perseid meteor shower “peaks”, as astronomers call it, when the Earth turns in its rotation to face the comet debris. This occurred in the hours leading up to sunrise Thursday morning and allowed for the most amount of meteors to be seen. Perseid meteors pass through the atmosphere around 60 miles above Earth’s surface at upwards of 130,000 miles per hour and are on average the size of a grain of sand. Perseid meteors can be larger, around the size of a marble, and such rock fragments burn brighter and longer in the atmosphere. The larger Perseids can even illuminate the ground like a flash of lightning if you’re lucky enough to witness one of these “fireballs”!
The timing of the Perseid meteor shower was excellent for me since I was working at Mount Rainier National Park as an astronomy interpretive ranger. Mount Rainer National Park has a beautiful dark sky due to being far from major cities and high elevation. The high elevation where I was observing from (~6,500 ft) made the night sky even more crisp and clear because I was looking through a less thick section of the Earth’s atmosphere compared to at sea level. Between the hours of 2:00 – 4:30 am I counted over 200 Perseid meteors, which means there were over 100 meteors per hour!
During this meteor shower my goal was to take an image of the Milky Way over the summit of Mount Rainier. To accomplish this, I hiked up the trail near Sunrise on the eastside in Mount Rainier National Park. This area afforded me the opportunity to face the camera south with the Milky Way and Mount Rainier aligned in the foreground. I setup my DSLR camera on a tripod and plugged in an intervalometer, which allowed me to take a sequence of images at my desired settings. I used a Nikon D800 with a 24mm lens at F/1.4 and ISO 3200. I continuously took 13 second exposures for over 2 hours and delayed for 1 second between frames so the camera could write the previous image to the memory card. While the camera took the nearly 250 images, I laid down and watched the magic of the Perseid meteor shower unfold before my very eyes!
Once the sequence of images was taken I found that the camera captured around 50 Perseid meteors. From this set of data I wanted to create an image with as many of these meteors as possible. To this end, I used Photoshop to create a composite image with all the meteors. I first used an image of the Milky Way over Mount Rainier to serve as the main image to build upon that was one of the first frames the camera took. To put all the meteors in the sky I had to first manually align each of the 45 images on the main photo’s star field. Aligning each image on the main photo’s star field allowed me to put the meteors in their proper place as they went through the sky. I used Photoshop to create a new layer for each image, then hid the entire layer except for the meteor. I would then brush in the meteor after aligning the star field. I repeated this process for the remaining 44 images. After around 5 hours or so of work the image was complete! This image will help me recall just how wonder the Perseid meteors were this year. I made a lot of incredible memories while working at Mount Rainier National Park, and this image is one of them. Feel free to try this technique for an upcoming meteor shower such as the Leonids and Orionids! Remember though, travel far from city lights if at all possible. Lastly, soak up and enjoy the power and magic of a star filled night sky, especially with friends and family.
I hope you find these tips useful. If you have any questions about this technique please send me an email at mdieterich58@gmail.com.
Keep looking up!
~Matt
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