Our Home, the Milky Way Galaxy

August 2016

Briefing date: August 25, 2016 (3:00pm)


Dr. Brandon Lawton (Space Telescope Science Institute)


  • Dr. Sean Carey (IPAC)

  • Dr. Dan Patnaude (CfA)

  • Dr. Jessie Christiansen (IPAC)

  • Dr. Seth Digel (SLAC National Accelerator Laboratory)

Slide presentation:

Transcript and audio recording:

Additional resources:

  • NASA Wavelength resources* (PDF file) 1.9 MB
    *Due to changes in the NASA Wavelength resource database, please use the attached resource PDF in lieu of nasawavelength.org URLs listed in slides. Original activity URLs should operate as normal.


Astronomers now know that there are hundreds of billions of galaxies in the observable universe. Humans have been observing one of those galaxies for millennia — our home, the Milky Way galaxy. People looking up at the night sky will notice that the sky looks quiet, peaceful, and unchanging. But if we look closer, we get a very different impression. NASA telescopes allow us to take that closer look into our galaxy. We've found a bustling metropolis full of activity, change, and renewal. In this Universe of Learning briefing, astronomers from across a multitude of NASA Astrophysics missions will describe how NASA's fleet of telescopes are working together to understand our home galaxy, including the structure of the Milky Way, star formation, stellar death, frequency and characteristics of exoplanets, and the enigmatic center where a supermassive black hole resides. In addition, we will point to some additional resources about the Milky Way galaxy developed by the NASA Astrophysics missions.


Dr. Sean Carey is the IRAC instrument support team lead at the Spitzer Science Center, part of the Infrared Processing and Analysis Center (IPAC) at Caltech. He has been interested in space and astronomy since watching the first lunar landing when he was three. His current day job is leading the team that enables the science coming from the Infrared Array Camera (IRAC) aboard the Spitzer Space Telescope. They are responsible for the calibration and processing of the data and helping astronomers around the world make the best possible use of the infrared images taken. Observing transiting exoplanets is a particular challenge as they are interested in very small changes (parts per million) in the observed brightness of the host star. Sean has been lucky enough to help in designing new ways of using Spitzer to characterize planets around other stars. As part of his job, he troubleshoots problems with the observatory, which is quite a challenge as Spitzer is now 140 million miles away. For his own personal research, he maps our galaxy in the infrared to help understand where and how stars form, and he helps find and characterize planets using Spitzer to study transiting exoplanets and planets detected through microlensing. When he can make it outside, he enjoys playing and coaching soccer.

Dr. Dan Patnaude is a staff astrophysicist for the Chandra X-ray Center, located at the Harvard-Smithsonian Center for Astrophysics. Dan plays a key role in daily operations and science mission planning for the Chandra X-ray Telescope, one of NASA's Great Observatories. His research interests include supernovae and their remnants, and in particular, how supernova remnants can inform us about the end-stages of stellar evolution. Prior to his current position, Dan was a postdoctoral fellow at the Smithsonian Astrophysical Observatory. Dan received his PhD in Physics and Astronomy from Dartmouth College in 2005, and his B.S. in Astronomy from the University of Massachusetts in 1995.

Dr. Jessie Christiansen is a staff scientist at the NASA Exoplanet Science Institute, and science curator at the NASA Exoplanet Archive. She is involved in the discovery and characterization of extrasolar planets via the NASA Kepler/K2 mission, paying specific attention to measuring how common Earth-like planets might be throughout the Milky Way. She is also involved in the planning for the upcoming NASA TESS mission, which will search the whole sky for the nearest planets to Earth. Prior to her current role, Jessie was a staff scientist with the NASA Kepler mission at the NASA Ames Research Center, and prior to that was a postdoctoral research fellow at the Harvard-Smithsonian Center for Astrophysics. She received her PhD in 2008 from the University of New South Wales, and her Bachelor of Science (Hons) from the Australian National University.

Dr. Seth Digel is a senior experimental physicist in the Kavli Institute for Particle Astrophysics and Cosmology at the SLAC National Accelerator Laboratory. He is a member of the Large Area Telescope (LAT) collaboration for the Fermi Gamma-ray Space Telescope and has studied the diffuse gamma-ray emission of the Milky Way and the populations of gamma-ray sources that the LAT has detected. He is also a member of Dark Energy Science Collaboration and the Camera project for the Large Synoptic Survey Telescope. He received a PhD in 1991 from Harvard University and his BS in Physics from the University of Delaware.

Dr. Brandon Lawton is an astronomer in the Office of Public Outreach at the Space Telescope Science Institute (STScI), where he works as an Education and Outreach Scientist. Dr. Lawton works with the Hubble, JWST, and WFIRST outreach and communications teams, as well as with the broader NASA science education community, to deliver accurate cutting-edge science content to students, educators, and the general public.