Astronauts, Black holes, and Aliens: A Q&A with Kim
The following few questions are some of the most frequent questions I get when talking to people about what I do. I hope you enjoy finding out a little more about me:
So what do you do? Are you an astronaut?
I am definitely not an astronaut – but I have had the privilege to work with some of them. I am the Visualization Lead for NASA’s Chandra X-ray Observatory, and I’m based at the Smithsonian Astrophysical Observatory in Cambridge, Mass.
Sometimes, when people hear “NASA,” it’s followed up with, “Have you ever gone up into space?” Though I did want to be an astronaut when I was a little kid, these days my feet are firmly planted on the ground. Only about 560 people in the history of humanity have been trained astronauts, and they have stronger stomachs than I do.
The telescope I get to work for, Chandra, is one of NASA’s great observatories, a sister to the Hubble Space Telescope. Chandra was launched back in 1999, and in orbit it goes about a third of the way to the Moon at its farthest point from Earth. Chandra looks at the high-energy regions of the Universe such as exploded stars, clusters of galaxies, and black holes. It’s pretty extreme physics. But X-ray data don’t really look like the more familiar optical data that we’re most used to seeing from, say, the Hubble telescope or even a backyard telescope (see photo of me, at left, with a friend's amazing telescope; photo courtesy of Stephanie A. Ewens).. X-ray light is invisible to human eyes.
So if we can’t see it, how do we make high-energy data accessible? That’s where my job comes in. I manage a team that approaches that question in a number of ways. My group has studied and applied new technologies to make sure the data takes the form that is both scientifically accurate and aesthetically pleasing. Essentially I use data from Chandra, as well as other telescopes, to tell stories about the Universe whether that story takes the form of a three-dimensional model of an exploded star, an image, or a tweet.
An artist’s illustration of NASA’s Chandra X-ray Observatory. Credit: NGST
Is this stuff for real?
With the fleet of telescopes in space and giant observatories on the ground, we are in what many consider to be a golden age of astronomy. These powerful telescopes produce thousands if not millions of images a year, many of which make their way into the public realm. We see them on billboards, in commercials, and across computer and tablet screens everywhere. Many of these images are spectacular, but I am often asked, “Is this real?”
When astronomers talk about light, they aren’t referring just to the kind humans can see with their eyes. This is a teeny tiny fraction of the light that exists. There are many kinds of light, from radio waves to infrared light to X-rays and gamma-rays. Each of these different types of light reveals something unique about the Universe. For example, infrared light generally shows cooler objects, while hotter and more energetic things give off X-rays. In order to truly understand and explore the Universe, astronomers need to collect all types of light.
In the past, astronomers used to capture images on film. Today, most data from all types of light arrives digitally, coded in the form of 1’s and 0’s. Scientific software is used to translate that data into a visual representation of the object, that is, an image. Scientists use additional processing to enhance the data, including things like removing artifacts, cropping in closer to the object of interest, and adding color.
So though some of the images of our Universe might look pretty fantastical, they are real. They aren’t giant selfies of the sky, but rather processed data that is translated into images that we can see. And really, just like in portrait or landscape photography here on Earth, the photographer has a point of view. He or she chooses the field of view, adjusts the lighting, adds or subtracts frames, etc. But those choices don’t make the resulting photo less real. In our case, we always make sure the science is the star.
An image of NGC 2392 (nicknamed the "Eskimo Nebula"), a planetary nebula, a phase that results when a star like the sun becomes a red giant and sheds its outer layers. X-ray: NASA/CXC/IAA-CSIC/N.Ruiz et al, Optical: NASA/STScI
Why should we care about space?
The sky belongs to everyone. Whether you live in Boston or Budapest or Bombay, every child and adult should be able to explore the Universe he or she lives in. And, in my opinion, astronomy is one of the most enticing portals to the greater constellation of STEM (science, technology, engineering and math) fields, particularly for the young and the curious. The notion of black holes and dark matter, and the discovery of new planets or the potential for life on Mars, can not only fuel the imagination, but also incorporate a variety of related disciplines including math, physics, chemistry, geology, and more.
It’s also hard to quantify the many other benefits humans have enjoyed thanks to our exploration of space – both by astronauts who go into orbit and by the telescopes who look out into cosmos on our behalf. There are countless spinoff technologies that have become part of our daily lives – everything from X-ray scanners in airports to the chips in your smartphone cameras. Beyond that, however, I think the pursuit of knowledge is something that helps define us as a society. We never know where science will take us, and it’s an important part of our species to explore and learn. Space is just one realm – albeit a rather large one – to make that happen.
Are there aliens out there?
I’m asked this question all the time and I love talking about it. The short answer is: No, researchers haven’t found any aliens (despite what the conspiracy theorists say). However, many do think it’s a distinct possibility that life in some form is out there. Here’s my take: I am certainly no astrobiology expert, but when we consider the explosion in the field of exoplanets (planets outside of our Solar System) over the past decade it’s pretty incredible.
When I started working in astronomy in 1998, there were only a couple exoplanet candidates detected at that point. Fast-forward to today and we have thousands. Astronomers now think that most stars in our Galaxy have at least one planet if not more. And when you consider the billions of stars in our Milky Way alone (not even counting the other billions of galaxies out there), the numbers of exoplanet candidates escalates quickly. If only a very tiny percentage of those are in habitable zones, there is at least a possibility for life on other planets. But of course, what form might that life take? Even if it were just a single celled organism, it would be an incredible discovery.
And that isn’t considering the places in our own Solar System where life might be able to thrive, or perhaps could have existed in a different time period. Mars isn’t off the table completely, nor is Venus. Both perhaps *could* have been able to sustain life at some point in the distant past. When you move out to some of the moons around the gas giants (Jupiter and Saturn, for example), there are yet more fascinating locations still waiting to be studied in detail.
One of Jupiter's most interesting moons, Europa. Credit: NASA/JPL
What is the coolest thing you’ve ever seen or learned about in astronomy?
This is rather hard to narrow down, as I literally learn something new every day in this job. But I would say that getting to know more about our home galaxy, the Milky Way, is one of my favorite things. Particularly, learning about the black hole at the center of our Galaxy has been fascinating.
Just a few decades ago, black holes were the stuff of science fiction. Today, we can pretty much watch black holes in action. A black hole is a dense, compact object whose gravitational pull is so strong that—within a certain distance of it—nothing can escape, not even light. Black holes range in size from a few times the mass of the Sun to millions or even billions of times the Sun’s mass. Using Chandra, astronomers have learned a great deal about black holes and how they influence their environments. One of the most important black holes to study is the one found at the center of our Milky Way galaxy. Astronomers have even given it a name -- Sagittarius A* -- and we know this black hole is about 4 million times the mass of the Sun.
Black holes are often set up as giant vacuum cleaners, sucking up all the material that comes anywhere near them. Of course some material does indeed pass the “event horizon,” or the point of no return, to be lost within the black hole’s incredibly strong gravitational pull. But that danger zone is a relatively small area around the black hole, comparatively speaking. Black holes are actually more like giant cosmic recycling centers. They have a big influence on the material all around them, from their powerful jets, to their flares that push material away from the black hole and back out into the cosmic environment.
Scientists have learned much about black holes so far, but the exciting thing is that they are just getting started. That’s the great thing about studying space and, really, science in general – you never know what you are going to find next. The fun part is being able to take that ride (for me, from the safety of the ground) and explore.
The Galactic Center and the area around Sagittarius A*. Credit: NASA/CXC/Univ. of Wisconsin/Y.Bai, et al.