Photographer to the Stars
Since its launch into low Earth orbit in 1990, the Hubble Space Telescope has captured some of the most stunningly beautiful images of our visible universe. Processing these images and preparing them for the public eye is Zolt Levay, Imaging Group Lead in the Office of Public Outreach at the Space Telescope Science Institute, AKA 'the Hubble images guy' - a title he humbly goes by on Twitter.
As the NASA/ESA Hubble Space Telescope celebrates its 25th year in orbit, we took the opportunity to talk with Zolt about the profound importance of such heavenly imagery and the significance this astronomical endeavour has on our lives.
The cosmos is a stunningly beautiful thing to be observing every day. Do you consider yourself to be in a position of great privilege having access to the ultimate pair of binoculars, so to speak, on what Sagan famously called “the shores of cosmic ocean”?
It is certainly a privilege to work with some of the best astronomy data ever, and to work among dedicated, talented professionals on the Hubble Team to be able to make Hubble’s results available to everyone in the world. Of course, it’s not quite as romantic as sitting at the controls of the world’s most powerful telescope. After all, Hubble is built to do science and takes the efforts of a huge team to operate. Scientists propose observations which are reviewed by panels of other scientists. The results are made available to everyone and analysed for many years. The images seen and reproduced worldwide originate from science programs and illustrate announcements of the results. I am honoured to have a hand in publicising these results around the world.
What initially attracted you to the Hubble Heritage Team?
[The Hubble Heritage Project was founded by a group of astronomers in 1998. The team releases, on an almost monthly basis, pictures of celestial objects like planets, stars, galaxies and galaxy clusters.]
I became interested in technology and science – astronomy in particular – early in my life. I also developed a strong interest, a passion really, for photography. Although I obtained a graduate degree in astronomy, I didn’t quite follow the “standard” path to an academic career. I also studied computing and programming and spent some years developing software for several NASA missions, finally ending up on the Hubble mission at the Space Telescope Science Institute. Eventually an opportunity came available to produce images and graphics to help publicise Hubble’s results, which seemed like a pretty good fit to my experience with astronomy, software, and photography.
You’ve taken on quite a commitment with Hubble, what makes a man dedicate his life to examining outer space?
It wasn’t hard to make a commitment to the Hubble Space Telescope; even well before launch when I joined the project it was NASA’s flagship space science mission, expected to accomplish great things. Early on in the mission, it was more difficult; with grave concerns about the telescope’s serious problems and whether they would be overcome or the mission would have to be scrapped. But since Hubble was repaired, and with every subsequent servicing mission, the telescope has become better than ever and the rewards have been gratifying.
For the most part, I work with the images and other aspects of the job day to day, with not too much thought to the broader consequences. But recent attention surrounding the 25th anniversary of Hubble’s launch has provided an opportunity to look at Hubble’s accomplishments and the images in particular with a broader view. We have been able to produce and publicise a collection of amazing images that complements Hubble’s powerful science discoveries and provides everyone with a view of the universe from Hubble’s unique perspective.
Hubble is allowing us to discover more and more about our universe. What, for you, has been the most astounding thing that Hubble has uncovered?
One of the most amazing aspects of nature is how connected it all is and how the scales of size and time are so immensely varied – mostly remarkably different from the perspective of normal human experience. How matter behaves under the influence of nuclear forces operating at the infinitesimal scales of atoms is connected to the formation and destruction of stars and galaxies powered by the energy released by those atoms, along with the action of gravity over cosmic distances. The matter in space is recycled on a cosmic scale; we are made of elements that were created in powerful supernova explosions that ripped apart massive stars. “We are all star stuff”, as Carl Sagan famously described it. But I also think it’s astounding that humans have evolved to be able to deduce how nature works even at the extremes of the most un-human scales, through observation and experimentation.
“One of the most amazing aspects of nature is how connected it all is and how the scales of size and time are so immensely varied...”
President Obama recently tweeted an image from Hubble. How much does Hubble interact with politics worldwide, are world leaders keen to know what’s out there?
I’m sure many world leaders are curious about the natural world and the cosmos in particular, as are most people, though they are certainly busy focusing their attention on solving day-to-day issues of policy and running governments. It was gratifying to see that President Obama felt that the results from Hubble were important enough to tweet about. In general, the space program and Hubble in particular have been fortunate to enjoy broad support from taxpayers and governments over their lifetime, even as there are discussions of how best to carry out the broader space policy. Many leaders acknowledge the contributions of NASA and missions such as Hubble in not only furthering our understanding of nature and the larger universe around us, but also the role in inspiring people, particularly students, to engage in learning and applying knowledge to solving the world’s problems. I would hope that leaders would be aware of the discoveries of science and apply the results of sound science to making decisions on policies that affect us all.
Technology is advancing and becoming more effective at an astonishing rate, what does this mean for the world of astronomy and your line of work in particular?
Advances in technology allow us to continue exploring the universe with greater power and precision. We will continue to see advances to allow exploration in different energies to address more difficult questions. The James Webb Space Telescope, planned for launch in 2018, exemplifies this; using cutting-edge technologies to collect and record the faintest infrared light from nearby to the edge of the universe will hopefully answer questions that are beyond the limits of Hubble’s capabilities. Just as important are the developments in technology that allow everyday citizens worldwide to have access to the results of science much more than ever before, and even to participate in exploration and discovery themselves. The availability and affordability of amazing telescopes, cameras and computing power – that would have been the envy of professional astronomers not long ago – allows many people to pursue astronomy as never before.
I understand that currently the images taken by Hubble are captured in black and white and filters are used to determine the colours. Is the final image how our eyes would perceive these celestial bodies?
Hubble’s cameras do not automatically produce images in colour. The cameras are designed to record brightness as accurately as possible. Nevertheless, the cameras produce images, and we provide the final step to convert the data into colourful images, not unlike what happens automatically in most everyday cameras. Filters in the camera allow selecting particular colours from the white light collected by the telescope. Images of a given object are made using different colour filters, we reapply colour to these images and combine them into a colour photograph. Even our eyes perform the same magic; separating the scene by colour and our brain reconstructs the colour images we perceive. However, since Hubble’s cameras operate differently from our eyes, the final images are not like what we would see visually for the most part – even if we could look through the Hubble telescope directly.
We strive to visualise in the images as much as possible of what is recorded in the data. Doing so we adjust the images to show details of the information in the full range of brightness recorded by the cameras. This involves a combination of science and art, objectivity and subjectivity, no different really from what any photographer might do in printing from a negative or working with “raw” images from a digital camera – in general the colours in the Hubble images are more vivid and the objects appear much brighter than what our eyes would see. Hubble images are spectacular not because of what processing techniques we use, but because the material we work with is some of the best astronomical data available.
“Eventually we will have samples returned from planets, asteroids and comets and it may not be long before we find evidence of life on planets around other stars.”
Of all the images you’ve sourced, which stand out as your favourite so far?
Many of the Hubble images are very powerful to me. One of them is the Carina Nebula, a dynamic region in our Galaxy where stars are actively forming from dense clouds of gas and dust. Both visually and conceptually the image shows this activity and has a great deal of detail that can occupy a lot of time in exploring. Another image I keep coming back to is NGC 1300, one of the best examples of a type of galaxy called a barred spiral. Besides the elegant, dramatic form of the bold spiral structure, amazing details appear in the colour composite: beautifully resolved spiral arms and dust lanes right to the bright nucleus, numerous star-forming regions starkly delineated in the light of hydrogen, a disk transparent enough to see distant background galaxies through, providing a dramatic feeling of depth.
Science has made great strides in mapping our visible universe. How did we get by in doing so without Hubble and what specifically did Hubble bring to the table?
It is certainly an amazing, powerful machine, but it is as much an evolutionary step in astronomical observatories as it is revolutionary. As Isaac Newton famously wrote, we stand on the shoulders of giants; most of what we know about the cosmos was learned before Hubble was launched, using powerful telescopes on high mountains firmly attached to the Earth. But even the most powerful telescope on the ground is limited by the distortion of the light from the universe caused by the atmosphere. By launching into orbit, above the obscuring atmosphere, Hubble has a clearer view of the universe. Edwin Hubble, after whom the telescope was named, made profound and fundamental discoveries nearly 100 years ago with telescopes on Mount Wilson and Palomar in California. Many other telescopes on the ground and in space continue to study the universe and make discoveries every day, adding to our knowledge immeasurably.
How bright is the future of space exploration?
The future is very bright for space exploration, as long as governments, taxpayers, and corporations are willing to continue devoting the resources to it. It is expensive, difficult, and risky to launch anything into space, but the payoffs in knowledge and inspiration are incalculable. NASA and space agencies around the world continue to support existing space missions and plan and develop new ones. Many exciting things are on the horizon, from astronauts returning to orbit and ultimately the Moon, or exploring asteroids and even Mars, to robotic observatories and probes that will continue to explore the Solar System. Eventually we will have samples returned from planets, asteroids and comets and it may not be long before we find evidence of life on planets around other stars. The James Webb Space Telescope will launch in 2018 to follow up on Hubble’s discoveries and push the understanding of the universe much closer to the Big Bang.
So, when you’re not occupied with space, what do you enjoy doing with your time?
I derive a lot of energy from powerful landscapes such as the great U.S. national parks, but also from great cultural centres such as the old established cities of Europe, with amazing architecture, monuments and museum collections. For much of my life I have pursued photography passionately and tried to capture the essence of places I visit in photographs, with varying degrees of success. I have also been deeply interested in astronomy for just about as long and these interests often intersect; I try to incorporate the night sky in photographs of landscapes and of course I was drawn to study astronomy and pursue it as a career. Other interests seem to centre around old established styles and design that has withstood the test of time: I enjoy classical music, the history and artefacts of ancient civilisations, Old Masters and Impressionist paintings. More philosophically, I find it very important to preserve and protect what we have in the natural world, the landscape, including the night sky, and historical artefacts and hope we can find sustainable ways to use precious resources.
What are you currently most enthusiastic and excited about in the world of science?
The Philae lander woke up on Comet 67P after landing and then going to sleep because it was in shadow and its parent Rosetta continues to orbit as the Comet approaches the Sun. There is a probe orbiting the dwarf planet Ceres, and the New Horizons mission will fly by Pluto in just a few weeks. It’s astounding that we can build such extremely sophisticated devices to explore the Solar System remotely and learn a great deal about extremely distant worlds. We live in an amazing time when sophisticated technology, communication and software analysis tools are contributing to an explosion of understanding in all areas of science, even as we are flooded by information and data.
Canyon de Chelly
One of my favorite places to visit is Canyon de Chelly, a fairly remote, spectacular red-rock desert landscape within the Navajo Nation in northeast Arizona (also a U.S. National Monument). There is no mystery why these spectacular landforms are sacred to the native people.
Antonín Dvořák's Symphony No. 9
(From the New World) is a monumental, romantic symphonic work with anthems inspired by grand American landscapes as well hymn-like passages evoking Native American and African-American melodies.
Claud Monet - Rouen Cathedral
I am in awe of Claude Monet’s series of impressionist paintings depicting the Rouen Cathedral in varying light conditions, from the same visual perspective.