CNN: What is the main goal of your research program?
Kalirai: The main goal of my research is to understand the details of how stars like our sun, including those that are a little more and a little less massive, change over time. For billions of years, these stars will remain at the same brightness and temperature. This is great for humans on Earth since it gives us a stable climate. After the hydrogen in the sun is exhausted, the sun will become a stellar cinder and simply cool over time. We call this state, the end state of 98% of all stars, white dwarfs.
All of the action in stellar evolution occurs between these two phases, when, over a relatively short time scale, stars swell up into "giants" and spill their outer materials into space. The detailed understanding of this process, of how stars dramatically change, is fundamentally important to many research areas in astronomy. After all, the light that we see from distant galaxies is really just millions of individual stars at the tip of their luminous evolution.
CNN: If the sun will experience this dramatic change, what is the fate of our planet Earth?
Kalirai: The Earth is orbiting the sun at a distance of about 90 million miles. When the sun runs out of hydrogen in its core, it will begin burning hydrogen in a shell around the core and become very luminous and bloated. The outer layers of the sun will actually reach the Earth, and so the oceans will evaporate and our planet will be fried. Sorry! Fortunately for us, this won't happen for several billions of years.
Based on my research on "stellar mass loss," the sun itself will lose about 45% of its mass through this process. The remaining mass, the core of the sun, will be the white dwarf. Interestingly, the size of that core will only be a little larger than the Earth, so the remnant star will be very dense.
CNN: What telescopes do you use to study the stars?
Kalirai: I enjoy using the Keck telescopes on Mauna Kea in Hawaii. Over the past seven years, I've traveled to Hawaii to collect data from these telescopes more than a dozen times. The Keck telescopes are two of the biggest optical telescopes we have on Earth. The mirrors stretch over 30 feet across and the building itself is bigger than a house.
The site of the telescopes is also beautiful. Mauna Kea is a dormant volcano, and the telescopes sit at the peak, at the distance of 13,000 feet. It's a harsh environment to observe from since there is about 40% less oxygen at that altitude than sea level.
CNN: You recently received an award from the American Astronomical Society called the 2013 Newton Lacy Pierce Prize. What does it mean to your career, and how does it affect your future endeavors?
Kalirai: The Pierce Prize is the biggest honor that I've received in my life. I am very passionate about astronomy and work very hard, so receiving the Pierce Prize tells me that the rest of the astronomy community values my contributions. This means a lot to me and will motivate me to work even harder in the future.
CNN: What do you see as the major achievement of the Hubble Space Telescope so far and its most important discoveries?
Kalirai: Actually, I think its best years are ahead of it. It's amazing when a scientific tool can rewrite a textbook, but Hubble has managed to do it countless times. In 2009, astronauts serviced Hubble and put two new cameras on the telescope. These instruments are functioning fantastically, and the demand for Hubble observations by the astronomical community is the highest that it's ever been. I have absolutely no doubt that Hubble will continue to amaze us with new discoveries about the universe.
CNN: You also spend a significant part of your time working on the James Webb Space Telescope, the successor to Hubble. Tell us about this fascinating project?
Kalirai: The James Webb Space Telescope is one of the most ambitious scientific projects that humans have ever undertaken. NASA has partnered up with the European and Canadian space agencies to build an unprecedented telescope, one that is the size of a tennis court and will launch 1 million miles away from Earth. (Hubble orbits at 350 miles.)
Webb, as we call it, will be 100 times more powerful than any other telescope we've made, and is designed to revolutionize our understanding of the universe. It will seek the first stars and galaxies that formed in the universe, solve mysteries on how stars and planets form and look for water in the atmosphere of other worlds. I can't wait to use it.
CNN: What are the most rewarding things about being a scientist?
Kalirai: Professionally, it's the fact that there is continuous satisfaction in expanding our knowledge of the universe. There are countless mysteries about the universe that we presently don't understand, and it's amazing to be a part of the process that will yield answers to these questions.
Personally, it's very rewarding to see young people becoming curious about the way things work. I spend one day every month doing public outreach, where I visit science centers, planetariums, classrooms and other venues to communicate science. As I get kids excited about the STEM fields (science, technology, engineering and mathematics), I always try to leave a little nugget of information untold. It's extremely rewarding to get the phone call or e-mail afterward when you realize that you've sparked their interest in science.
To see what scientific thoughts are on Kalirai's mind today, you can follow him on Twitter at @JasonKalirai. Information about his research is also available on his Web page, www.jasonkalirai.com.