Astrophotography Blog

Capturing the enchanting world of astrophotography , where the stars become storytellers and the cosmos unveils its mysteries. Avitar Photo: W. M. Keck Observatory by John O'Meara Header Photo: By Allexxandar

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Astronomy Photographers of the Year 2023

The photo above was shot by Marcel Drechsler, Xavier Strottner, and Yann Sainty, Capturing a moment of breathtaking beauty, earning them the title of Astronomy Photographers of the Year 2023 for their mesmerizing image, "Andromeda, Unexpected."

Source: Royal Museums Greenwich

Andromeda, also known as Messier 31 or M31, is a spiral galaxy located approximately 2.537 million light-years away from Earth. It is the nearest spiral galaxy to our own Milky Way and is a prominent member of the Local Group, a collection of galaxies that includes our own and several dozen others. The history of Andromeda is as rich and complex as its luminous core, stretching back billions of years to the dawn of the universe itself.

The story of Andromeda begins with the birth of the cosmos in the Big Bang, a cataclysmic event that set in motion the expansion of space and time. Over billions of years, gravity drew together vast clouds of gas and dust, causing them to collapse and form stars. Among these stars were a family of galaxies.

Andromeda, like all galaxies, is a collection of billions of stars bound together by gravity. Its spiral arms, decorated with bright knots of star formation, wind around older, redder stars. At its core lies a supermassive black hole, a cosmic behemoth with a gravitational pull so strong that not even light can escape its grasp.

Andromeda's beauty is more than skin deep. It is a treasure trove of scientific knowledge, offering insights into the workings of the universe on scales both vast and small. Astronomers study its structure and dynamics to better understand how galaxies form and evolve over time. By measuring the motion of stars within Andromeda, they can infer the presence of dark matter, a mysterious substance that pervades the cosmos and binds galaxies together.

Astronomers believe that Andromeda is on a collision course with our own Milky Way, destined to merge in a cosmic tango that will reshape both galaxies in the distant future. This collision, which is expected to occur billions of years from now, will likely trigger a frenzy of star formation and reshape the landscape of both galaxies.

Drechsler, Strottner, and Sainty captured their award-winning image, "Andromeda, Unexpected." The photograph, taken with a combination of advanced telescopes and imaging techniques, reveals Andromeda in all its glory, its swirling arms and glowing core illuminated by the light of billions of stars. But what makes the image truly remarkable is the unexpected presence of a faint, wispy trail of gas extending from the galaxy's disk. A galaxy's disk refers to the flat, rotating component of a galaxy that typically contains most of its stars, gas, and dust.

This trail, known as a tidal stream, is remains of Andromeda's past. It is the result of gravitational interactions with smaller, satellite galaxies that have ventured too close to Andromeda and been torn apart by its immense gravity. These interactions have left their mark on Andromeda's structure, sculpting its shape and leaving behind a trail of stars and gas that serves as a silent testament to the galaxy's history.

Sources: Wikipedia, NASA Science, EarthSky, Britannica

Drechsler, Strottner, and Sainty's photograph captures not only the beauty of Andromeda but also the dynamic and ever-changing nature of the cosmos. It reminds us that galaxies are not static, unchanging objects but living entities that evolve and interact with their surroundings over billions of years.

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A Journey Through the History of Astrophotography

Astrophotography is the art and science of photographing celestial objects, allowing us to peer into the depths of the cosmos with exceptional clarity and detail. Such photos that have mesmerized humanity for centuries.

However, you may not know the history and evolution of astrophotography throughout the centuries of its existence. Astrophotography has evolved in tandem with humanity, progressing from its humble origins to become an integral component of modern scientific exploration.

The roots of astrophotography can be traced back to the early 19th century when astronomers began experimenting with capturing images of the night sky. On of the earliest pioneers was French astronomer Joseph- Nicephore Niepce, who in 1826 produced the first known photograph of the moon.

Source: Wikipedia

However, it was the British polymath john Herschel who made significant strides in the field of astrophotography with his experiments in the 1830s, capturing images of the moon and other celestial objects using early photographic techniques.

Source: Wikipedia

The late 19th and early 20th centuries witnessed a golden age of astrophotography, marked by technological advancements and ambitious projects. The development of dry plate photography in the 1870s made astrophotography more accessible to astronomers worldwide, leading to the creation of observatories and photographic surveys. One of the most notable projects of this era was the Carte du Ciel, an international effort to map the entire night sky through photography.

Source: Wikipedia

Photographic plates became the predominant tool in astrophotography during the late 19th and early 20th centuries, allowing astronomers to capture faint and distant objects with unprecedented sensitivity. Innovations such as the use of sensitive emulsions and long exposer times enabled astronomers to push the boundaries of astrophotography, revealing new insights into the cosmos. The work of astronomers like Edward Pickering at the Harvard College Observatory and George Ellery Hale at the Mount Wilson Observatory paved the way for groundbreaking discoveries in astronomy.

Source: Wikipedia

The later half of the 20th century saw a gradual transition from photographic plates to electronic detectors in astrophotgraphy. Charged-coupled devices (CCDs), first developed in the 1960s for use in telecommunications, revolutionized the field by offering superior sensitivity, resolution, and efficiency compared to the photographic plates. The use of CCDs by astronomers in the 1980s and 1990s directed a new era of digital astrophotography, allowing the capture of high-quality images of celestial objects with remarkable accuracy.

Source: Sky & Telescope

No discussion of astrophotography would be complete without mentioning the Hubble Space Telescope, one of the most iconic and influential astronomical instruments ever created. Launched by NASA in 1990, the Hubble revolutionized the understanding of the universe with its breathtaking images of distant galaxies, nebulas, and other cosmic wonders. The Hubble is equipped with advanced CCD cameras and other cutting-edge instruments, the Hubble continues to capture stunning images that inspire the future generation of astrophotographers.

Source: NASA

In recent decades, advances in digital imaging technology have democratized astrophotography, allowing armature astrophotographyers can capture stunning images of the night sky from their backyard observatories. Many amateur astronomers have made significant discoveries and contributed valuable data to professional research projects, demonstrating the power of citizen science in advancing our understanding of the cosmos.

While Traditional astrophotography focuses on capturing images in the visible spectrum, astronomers have increasingly turned to other wavelengths of light to study the universe. From radio telescopes to X-ray observatories, a multitude of specialized instruments have been developed to observe celestial objects across the electromagnetic spectrum. Each wavelength reveals unique insights into the nature and behavior of cosmic phenomena, advancing our understanding of the universe.

Source: NASA

As technology continues to advance, the future of astrophotography holds boundless possibilities. From next-generation space telescopes to ground-based observatories equipped with state-of-the-art instruments, astronomers are poised to unlock new realms of discovery in the coming decades. With the beginning of artificial intelligence and machine learning, image processing techniques are become increasingly enhanced, allowing astronomers to extract more information from astrophotographic data than ever before!

Astrophotography has come a long way since its humble beginnings in the 19th century, evolving from the early experiments of pioneering astronomers to the high resolution images captured by current day telescopes and space craft. Through the lens of astrophotgraphy, we have captured the beauty and vastness of the universe, expanding our horizons and inspiring generations of scientist, artist and enthusiasts alike. Astrophotgraphy will continue to illuminate the wonders of the universe and strengthen our appreciation of the immensity and complexity of the universe we reside in.

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Completed Crab Nebula

The photo above is my first ever fully completed photo in astrophotography. Thanks to the help of GIMP, I was able to do all the necessary steps to allow me to start my journey in Astro-photography.

Thankfully, the astronomy database had pre-calibrated images of the crab nebula from January 5th, 2020. This allowed me to skip the drawn-out process of calibrating images. What does that mean? Calibrating images involves adjusting and standardizing the colors, brightness, accuracy, and consistency within an image. This process ensures that the red, blue, green, and luminance layers look consistent. Not only does calibration help with consistency, but it also sets the brightness and contrast to allow clear visibility while also preventing images from being either too dark or too bright.

So, if I didn’t calibrate the images, what did I do? I went over a lot of what I did to this image in another post “Work in Progress Crab Nebula.” However, I’ll roughly go over what I did to the image overall.

After other astronomers calibrated the crab nebula photos and made them available to me in the database, I took the red, blue, green, and luminance images and converted them onto GIMP. This made the different filters into different layers.

From there I adjusted the brightness and color contrast of each layer. This allows for the brighter pixels in the images (which happen to be stars) to become brighter without brightening the far dark pixels (the space behind and/ or in between the stars.)

Since all the images are layered on top of each other, I can only see the images that are layered first. To combat this, I needed to change the opacity of each layer. This allowed me to see all the colored images at once.

Another adjustment needs to be made. Now that all the images were shown together, I could see that they were not all lined up. To line up each of the images I had to search each layer and find the most notable star that was the same in each image.

It doesn’t end there; however, Since I wanted to get more of the intricate details within the nebula itself, I turned up the brightness of the image. This allowed me to see more of the stars in the galaxies and a larger array of colors as well. Not only did turning up the brightness affect the stars, but I could now see more dust clouds along with red lines streaking through.

I wasn’t a fan of how reddish/ brownish the image looked and decided to change the brightness of the red layer and the green layer. I lowered the red layer, getting rid of the reddish/brownish hue over the image. In turn, I enhanced the green layer and slightly the blue to allow more of a cool colored finish without taking away from the red stars and the redness inside of the nebula.

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The Importance of Calibrating Images

In the world of digital astrophotography, accuracy is crucial. The reliability of your images is essential to analyzing your images. This is where image calibration comes in. Calibrating images is a process that ensures consistency, accuracy, and reliability in the visual data we capture and analyze. Calibrating images involves several techniques. These are dark calibration images, flat calibration images, and the combined use of both.

Dark Calibration Images: These images capture the noise inherent in the camera sensor when no light is present. They help correct for sensor noise and other imperfections.

Flat Calibration Images: These images capture the uniformity of light across the sensor. They help correct for vignetting, dust spots, and other irregularities.

Dark and Flat Calibration Images: By combining both dark and flat calibration images, we can address a broader range of imperfections, resulting in more accurate and reliable calibrated images.

Median Calibration Images: Unlike the average mode, which simply adds up pixel values and divides by the number of images, the median mode selects the middle value of each pixel across all images. This method eliminates outliers and noise, providing a cleaner and more accurate calibrations.

Calibrating images ensure that our data is as reliable as possible, allowing us to make informed decisions and accurate conclusions.

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Work In Progress Crab Nebula

What exactly is the colorful spectacle above? Would you believe me if I said this is the Crab Nebula? Believe it or not, it is!

However, the image above doesn’t seem to resemble a crab, so what’s with the name? The name comes from an Astro-photographer back in the early 1840s, William Parsons. Unlike astrophotgraphers now, Parsons didn’t have access to modern day telescopes, nonetheless cameras. So how did he take the picture? Like all early astrophotgraphers, Parsons spent his nights gazing at the galaxy with his telescope and hand drawing what his eye could see. From what he could see, the Crab Nebula looked similar to a crab with arms.

Source: wikipedia.org

Perhaps that’s where the ‘crab’ in Crab Nebula came from, but what about the rest of the name. Well, nebula is a scientific name for the formations of gas, dust and other space materials that densely combine to create stars. The Crab Nebula’s formation was caused by a star called the “guest star” that turned into a supernova explosion.

Source: wikipedia.org and NASA

The image above was originally taken on January 5th, 2020 at Bridgewater State university’s observatory. The telescope at the university’s observatory does not take photos in colors. Well, not in the way one might suspect. It’s not like a regular digital camera. This telescope uses different filters with different colors. Which at first glance doesn’t look all to pretty. So how do astrophotgraphers make stars, and the galaxies look so mesmerizing? Well, the same way Instagram models do, by editing! That’s how I created the photo above, which is still being constructed on.

How did I get to the image above? By using the magic of GIMP! GIMP is a free editing tool available to anyone with access to either a computer or laptop.

Firstly, I had to have multiple photos of the Crab Nebula with different filter. These filters consisted of red, blue, green and plane jane black and white (luminance).

Secondly, I had to adjust the brightness and color contrast of the image as a whole. I did this by increasing the color contrast of each colorized image layer. This allows for the brighter pixels (stars) in the image to become even brighter without brightening the far darker pixels (empty space).

Thirdly, I needed to layer the individual colorized photos on top of each other. When doing this I could only see the image on the first layer (my luminance layer), and to combat this I had to change the opacity of all the images layered above another image. Then I could see all the colored images at once.

Fourthly, I realized that I may be able to see all of the images at once, they didn’t seem to line up. So I had to make some adjustments. After meticulously searching through each individual image, I found the star the was not only the most prominent but also the same exact star in each image. From there I was able to line up each induvial image to that said star. This is what allowed all of my photos to become perfectly aligned.

Finally, the vibrant photo above was created! However beautiful the Crab Nebula looks, I truly do not believe I have captured all of its glory. This is the reason it is still ‘under construction’. I would love to clarify my image a bit more and really go into the intricate details of the remnants of the star’s supernova explosion.

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Bridgewater State University Observitory

Earlier this week Jamie Kern, observatory manager and professor,  was kind enough to show her honors astrophotography class the University's observatory (shown above).

The Observatory was first built slightly off the colleges campus back in the 1970s, but was rebuilt in 2011 in Bridgewater State University’s math and science center. It contains a 14-inch Schmidt-Cassegrain telescope. Schmidt-Cassegrain telescopes cost roughly $4000-$6000.

What makes a Schmidt-Cassegrains telescope (SCT) so special? This telescope has become one of the most popular telescopes due to its versatility, compactness and portability. Its versatility allows users to take amazing photography, observing as well as stargazing significantly easier.

How does a Schmidt-Cassegrains telescope (SCT) work? “Schmidt-Cassegrain telescopes are a catadioptric design, meaning they use both lenses and mirrors. They are reflecting telescopes, but they use a corrector lens to eradicate any abnormalities that would result from the mirror alone. The incoming light passes through the Schmidt corrector lens (also called a corrector plate) at the front of telescope.” Which is reflected from a concave primary mirror at the back of the scope. This focuses the light to the front of the telescope where it is reflected again by a smaller secondary mirror. Finally, the light travels back through a hole in the primary mirror to the rear of the scope for visual observing or a camera for photographing.

Source: Starizona

What is the history of the Schmidt-Cassegrains telescope (SCT)? Well for those reading who have good old American nationalism will be happy to know that it was invented by James Gilbert Baker, an american astronomer and lens designer. The design was first intended for a camera in the 1940s. However, Bakers' design wouldn't be used as a telescope until World War II for research for the military.

Source: .wikipedia.org

[apod]

2024 January 18

Northern Lights from the Stratosphere Image Credit & Copyright: Ralf Rohner

Explanation: Northern lights shine in this night skyview from planet Earth’s stratosphere, captured on January 15. The single, 5 second exposure was made with a hand-held camera on board an aircraft above Winnipeg, Canada. During the exposure, terrestrial lights below leave colorful trails along the direction of motion of the speeding aircraft. Above the more distant horizon, energetic particles accelerated along Earth’s magnetic field at the planet’s polar regions excite atomic oxygen to create the shimmering display of Aurora Borealis. The aurora’s characteristic greenish hue is generated at altitudes of 100-300 kilometers and red at even higher altitudes and lower atmospheric densities. The luminous glow of faint stars along the plane of our Milky Way galaxy arcs through the night, while the Andromeda galaxy extends this northern skyview to extragalactic space. A diffuse hint of Andromeda, the closest large spiral to the Milky Way, can just be seen to the upper left.

∞ Source: apod.nasa.gov/apod/ap240118.html

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The Northern Lights, a breathtaking natural phenomenon, also known as Aurora Borealis, graces the night sky with their presence nearly every day. Depending on prevailing weather conditions and the level of light pollution in the atmosphere, optimal conditions for capturing the Northern Lights occur during the spring equinox. Nevertheless, one must act swiftly, as the spectacle typically lasts only 15 to 30 minutes.

For photography enthusiasts and adventurers alike, planning an excursion to witness this phenomenon demands meticulous attention to various factors. Beyond monitoring weather patterns and assessing light pollution levels, selecting the right location is paramount to optimizing the viewing experience.

Most auroras take place at a place known as the "auroral zone". These locations are high-altitude, with minimal artificial illumination and unobstructed horizons. This provides ideal vantage points for capturing the Northern Lights in their full splendor. The northern lights can be viewed from Arctic locations such as Alaska, Canada, Iceland, Greenland, Norway, Sweden, Finland, Scotland, and Siberia.

Source: travelandleisure.com and wikipedia.org

Furthermore, comprehending the science behind the Northern Lights enriches the experience for astronomers or even people who appreciate the cosmic world. Learning about the Northern Lights allows astronomy lovers to appreciate the intricate interplay of cosmic forces. The Northern Lights are created by energized particles from the sun slamming into the Earth’s upper atmosphere with shocking speeds up to 45 MILLION miles per hour. Luckily for us, the Earth’s magnetic field not only protects us from the energized particles but also redirects the particles towards the poles.

The bright and beautiful colors of the Northern Lights are from the chemical composition in Earth’s atmosphere. The photo above contains green light, closer to the Earth’s crust. This is due to the high level of oxygen molecules surrounding the Earth’s crust. Since there is so many oxygen molecules near the Earth’s crust, this makes the green light the most common light to experience. The red light, however, is due to the high level of nitrogen molecules and consequently the low amount of oxygen atoms. Red light is not the most common color to see. The red light tends to show during intense solar activity (like in the NASA photo above.)

The Northern Lights stands as a testament to the awe-inspiring beauty of nature and the harmonious synergy between Earth and the cosmos. By embracing the intersection of science and artistry, fellow star gazers can embark on a rewarding journey to witness this celestial marvel firsthand.

Source: wikipedia.org