Capturing a galaxy in a crystal ball

Astrophysicist Juan Carlos Muñoz-Mateos talks to us about photography, the universe and capturing a galaxy in a crystal ball.

Juan Carlos Munoz-Mateos is a Faculty/Operations Staff Astronomer at the European Southern Observatory in Santiago, Chile. His research focuses on the physical mechanisms that govern the formation and evolution of galaxies. He is also a keen photographer who loves photographing landscapes and the night sky.

Sunset storm, Paranal

Have you always had an interest in physics? How did you go down the path of astrophysics?

As a kid I was always very curious about finding out how things work. Later on, as a teenager, my parents bought me a small telescope as a present. One night I saw a rather bright object in the sky. I had no idea what it was, so I pointed the telescope towards it. At first all I saw was just a blurry blob, but as I focused the telescope the image became sharper, and the blob developed two ‘ears’. It turns out it was Saturn and its rings! I was immediately hooked, the feeling of being overcome by such an unexpected ‘discovery’ was amazing. I instantly knew I wanted to become an astronomer.

I finished high school in 2000 and moved from Don Benito, my hometown, to Madrid in order to study Physics at Complutense University. I graduated in 2005 and started my PhD in Astrophysics at the same university. I loved the experience of doing actual research and using professional telescopes.

I finished my PhD in 2010, and then moved to the US as a postdoctoral researcher. I spent 3 years in Charlottesville, VA, working at the National Radio Astronomy Observatory. Then in 2013 I was awarded a Fellowship by the European Southern Observatory (ESO), and I moved to Santiago de Chile. In 2015 I obtained a Staff Astronomer position also at ESO.

As an ESO astronomer my job has two components: my own personal scientific research, and technical duties for the observatory. I live and work in Santiago, where I do most of my research, but I also spend 105 nights per year at Paranal Observatory, in the Atacama desert in Northern Chile.

Paranal is a state of the art research facility, with numerous telescopes and instruments collecting photons under some of the darkest skies on Earth. My duties at the observatory involve carrying out observations for scientists all over the world.

Moon halo

How did you get into photography?

I’ve always had artistic inclinations. In fact this is something relatively common among the scientists I know: they often have hobbies related to visual arts, music, etc. But even though I dabbled a bit with photography as a teenager, it wasn’t until I moved to Chile that I got really serious about it.

For someone who loves photographing landscapes and the night sky, Chile is a perfect place to live. You can find all sorts of landscapes: arid deserts, humid forests, glaciers, volcanoes… you name it. Chile is also home to some of the darkest skies on the planet, and being in the Southern Hemisphere provides a unique view of the core of the Milky Way and the Magellanic Clouds—two small galaxies orbiting the Milky Way. A landscape and astrophotographer can’t ask for more!

In the particular case of astrophotography, being a professional astronomer has its pros and cons. Working at Paranal Observatory gives me easy access to amazingly dark night skies, but it’s also a demanding job, so I don’t have unlimited free time to take pictures. We have to schedule observations, analyse their quality on the fly, fix unexpected and often complex technical problems… and every single minute observing with these telescopes is expensive!

Milky way galaxy

So what I usually do is plan ahead what kind of shot I want to take. Do I want to capture the full Milky Way arching over a large panorama, or focus on a smaller portion of it? How do I want to frame and compose my image? Where should I place my camera? Once I make sure everything is running smoothly with the scientific observations, I leave them in the expert hands of the telescope operator, and I sneak out of the control room for 10 mins to take the shot, then come back to resume my tasks.

In a way these restrictions have really helped me improve as a photographer, because they forced me to plan my shots ahead.

Having to plan my shots ahead has helped me improve my skills in terms of framing and composition, which is what photography is all about in my opinion.

Can you tell us a bit more about being an ESO Photo Ambassador?

ESO has a serious commitment with education and public outreach, and astrophotography is a perfect way to bring astronomy closer to the public. The ESO Photo Ambassadors programme is a network of photographers who regularly take pictures of the night sky from the observatories managed by ESO, like Paranal (where I work), ALMA (an array of radio telescopes in the north of Chile) or La Silla (an optical observatory close to the city of La Serena). ESO then distributes our images through their social media, thus reaching lots of people all over the world.

It took me a few years to feel confident about my images. They were not bad, just not particularly remarkable compared to the thousands of night shots already out there. Over time I slowly built a portfolio of images that I deemed compelling enough, and submitted them for consideration to the Photo Ambassador programme.

Anyone interested in becoming an ESO Photo Ambassador should check the instructions in this link:

https://www.eso.org/public/chile/outreach/partnerships/photo-ambassadors/

Your galaxy in a crystal ball image had a great response, can you tell us more about how you captured this image?

I got the inspiration from macro photographers like Alberto Ghizzi and others, who shoot images of insects covered with tiny drops of water that refract the background behind them. I thought it would be interesting to try something similar with the Milky Way and a crystal ball.

I wanted to create the illusion of trapping something inconceivably large as a galaxy into something that fits in your hand.

I went for a walk to Lastarria, a neighbourhood in Chile that hosts a flea market at the weekend. I stumbled upon a stand selling all sorts of used items, including crystal balls. I didn’t think about it twice and bought one for a few bucks.

A few days later I went up to Paranal on one of my regular duty trips, and as usual I had already planned ahead the overall details of the shot. Unfortunately, this was a complex shot that I couldn’t execute in just a few minutes during my working hours so I decided to take the image after finishing my job, before going to sleep.

I was really tired and almost decided to go straight to bed, but I gathered some strength and left my bedroom armed with my camera, lenses, tripod and crystal ball. I placed the ball on top of the handrails of a corridor that leads to the underground residencia where we sleep at Paranal. I then mounted my camera on top of my tripod, and placed it at an angle below the crystal ball, pointing towards the Milky Way, which was already low in the horizon.

Milky Way galaxy in a crystal ball

“In art, a picture acquires a completely different meaning once you understand the motivation of the artist behind it. Similarly, nature becomes so much more beautiful when you understand the underlying physics.”

I chose a 24 mm lens, which gave me a field of view large enough to capture a significant portion of the Milky Way behind the ball. Focusing the stars within the ball was a nightmare. I usually focus on some bright star in real time, using the Live View function of my camera, but this didn’t work with the ball.

So I had to take several test shots, fiddling with the focusing ring in between until I got sharp stars. Then I had to choose an aperture, and I opted for f/4. Wider apertures let more light through, but the bokeh in the background was too large and made it impossible to discern the shape of the Milky Way. Narrower apertures, on the other side, yielded much darker images. The exposure time was 30 seconds, at ISO6400.

The image had indeed a huge response online, being shared more than 14000 times on Twitter, which I wasn’t expecting at all. I think this is because the image is quite abstract and allows people to re-interpret it in different ways. Most people told me it reminded them of the ‘Orion’s Belt’ scene in ‘Men in Black’. Others said it looked like Sauron’s Palantir in ‘The Lord of the Rings’.

This is something I’ve always found challenging about landscape and astrophotography: the subjects we shoot are very obvious and straightforward, and often don’t leave enough room for symbolism. I’ve always struggled to come up with shots that are evocative rather than being just visually nice.

Also, crystal balls have a bad reputation in photography, because more often than not they’re used as gimmicks with no storytelling purposes. I worked hard to plan and compose the image in a way that it made sense for the ball to be there, and I’m really glad to see that people appreciated that effort.

I was also very thrilled to have the image featured in NASA’s Astronomy Picture of the Day, which was always my dream as an astrophotographer.

Santiago Night

What kind of gear are you using—any specialist equipment for shooting the cosmos?

I shoot with a Canon 6D, whose sensor performs really well in low light conditions. In terms of lenses, astrophotography demands two qualities: large aperture, to gather as much light as possible, and great sharpness across the field of view, to get pinpoint stars from corner to corner.

The lens I use most often is the Rokinon/Samyang 24 mm f1.4, which is luminous and sharp, and has a perfect field of view for Milky Way photography. When I need a larger field of view I use a Rokinon/Samyang 14 mm f2.8 lens. They’re both manual lenses, which is not an issue in astrophotography, and are therefore much cheaper than similar lenses from major brands, while still delivering great image quality.

I’ve recently started shooting astrophotographs with the Tamron 45 mm f/1.8. It provides a smaller field of view that allows me to render finer details in the Milky Way. When I need more magnification, like when shooting the Moon or the Sun, I use a Tamron 100-400 mm.

A tripod is mandatory for astrophotography, as exposures are quite long in order to capture as much light as possible. I use a Sirui T-025X, which is ridiculously compact and lightweight, yet sturdy enough to support my camera and lenses with no problem.

For landscape photography I use a Canon 24-105 mm, which is my all-purpose workhorse lens, as well as the aforementioned Tamron 100-400.

How did you come across Affinity Photo? What are your main uses for it?

I discovered Affinity Photo back in 2015, through online posts by friends in social media. I downloaded the public beta and started to use it straight away. I immediately loved how easy and intuitive it was. For such a cheap one-time payment, I didn’t think about it twice and bought it.

One of the features I like the most about Affinity is how easy it is to edit images in a non-destructive way. Apart from Adjustment Layers like curves and so on, I love Live Filter Layers, which provide filters like high-pass, blur, etc. in a non-destructive way with just one click.

Another top-notch feature is the powerful blend range tool, which gives you full control on how to blend layers based on the tonal values of the selected layer and the underlying ones. This is not a simple ‘blend if’ tool: instead, you get full control of the blending range through a curves dialog. This makes luminosity blending a breeze. With this tool I’ve been able to seamlessly blend bracketed exposures within seconds, without the hassle of creating luminosity masks.

Finally, I recently discovered how easy it is to use the Nik plugins directly within Affinity. I often use some of those plugins for my night and landscape shots, and being able to do so without leaving Affinity is a big plus.

Parque Alerce Andino, South Chile

What do you like to do other than photography?

Reading is one of my main hobbies, I’m particularly fond of science-fiction. This might be a bit cliché for a scientist, but I love the idea of exploring human behaviour in a futuristic scenario. I also love comics, in particular anything penned by Alan Moore or Ed Brubaker.

I also enjoy doing outreach about astronomy. After all, the telescopes and instruments we use have been built with public money, so I firmly believe it’s our responsibility to explain to people what we do. Besides, astronomy sparks a lot of interest in the public, perhaps because it’s a such a visual and thought-provoking discipline. So I really like giving outreach talks or being interviewed to explain recent discoveries.

What’s the most impressive astronomical event or occurrence you’ve witnessed?

I was lucky to perform some of the first observations ever of the aftermath of the collision of two neutron stars.

I was in Paranal in August last year, and we got an alert about the detection of gravitational waves from a certain area of the sky. Gravitational waves are ripples in the fabric of space-time resulting from the collision of two massive objects, like black holes or neutron stars, both of which are corpses of now-dead massive stars. Gravitational waves distort space as they pass through, much like the ripples on a pond when you throw a stone. Here on Earth we have three gravitational wave detectors, two in the US and one in Italy. On Aug 17 2017, all three of them were triggered at the same time. Scientists were able to triangulate the area of the sky where the gravitational waves were coming from, and alerted observatories all over the world to point their telescopes there.

Gravitational waves had been already detected before, but all previous instances were due to colliding black holes that leave nothing visible behind. But this time the calculations showed that the colliding objects were neutron stars, meaning that it would be possible to actually see something, a light signal associated to the collision.

A team at Las Campanas Observatory were the first ones to observe the visual counterpart of the collision, in a galaxy located 130 million light years away. Other telescopes, including those at Paranal, confirmed the discovery independently: there was a point source on that galaxy that wasn’t there before.

Auxiliary Telescopes

That was perhaps the most hectic and exciting night I’ve ever had at Paranal. I don’t work in this particular sub-field of astronomy, but knowing that I was one of the first people ever to witness the light of the collision of two neutron stars was exhilarating.

The images themselves may not look stunning at first sight. After all, it’s just a little point of light. But knowing that it’s the result of the collision of two stellar corpses makes it so incredibly beautiful. I think this represents a deep connection between science and art. In art, a picture acquires a completely different meaning once you understand the motivation of the artist behind it. Similarly, nature becomes so much more beautiful when you understand the underlying physics

“The images themselves may not look stunning at first sight. After all, it’s just a little point of light. But knowing that it’s the result of the collision of two stellar corpses makes it so incredibly beautiful. ”


Follow Juan Carlos on Twitter to keep up to date with his astrophotography.


Read next: Stars Over Atacama - astronomical imaging at the European Southern Observatory.


Marketing assistant
Umar is our marketing assistant which basically involves knowing a bit about everything. He likes to tinker with computers, build things and play competitive games. His favourite colour is green and he enjoys bouldering, which is basically climbing without any ropes. It’s less dangerous than it sounds.
Credits & Footnotes

All images copyright of Juan Carlos Muñoz-Mateos and used with permission.