Understanding the Origins and Diversity of Planets

August 2018

Briefing date: August 2, 2018 (3:30pm EST)


Dr. Emma Marcucci (Space Telescope Science Institute)


  • Dr. Farisa Morales (JPL)

  • Dr. Hilke E. Schlichting (UCLA)

 Slide presentation:

Transcript and audio recording:

Additional resources:

  • NASA Wavelength resources* (PDF file) 1.2 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.


Understanding how planets and planetary systems form is critical to understanding the stages of planetary development and the uniqueness of our Solar System. The current understanding of formation is that planets and their star form from a collapsing cloud of gas and dust, or nebula. The resulting disk contains a central young star surrounded by the material needed to build planets. Over millions of years, disk material aggregates and grows into a number of planets, leaving little material left in the disk. Many contributions to the study of protoplanetary disks and planet formation have come from infrared views, such as those from the Spitzer Space Telescope, which can peer through dust clouds, and is celebrating its 15th anniversary this fall. In 2004, the Hubble Space Telescope was able to directly image a planet around another star with visible light using a coronagraph, just one tool astronomers use to study other planetary systems. Until relatively recently, the only example of a planetary system has been our own; however, over the past few decades the detection of exoplanets has shown the diversity of planets and planetary systems and contributed to our understanding of how planetary systems form. Astronomers study other solar systems to address fundamental questions about our knowledge and place in the universe, such as “how does the universe work” and “are we alone”?

In this briefing, speakers will share content about planetary formation and the diversity of planets, leading us to explore the uniqueness of our Solar System. The briefing will also include information about the tools and techniques scientists use to study these systems. Dr. Farisa Morales will speak to the formation of planets in disks; Dr. Schlichting will discuss the origin and diversity of exoplanets and explain how what we have learned so far helps place the formation of our own Solar System into context. The briefing will also include a review of resources related to disks and exploring types of exoplanets.


Dr. Emma Marcucci is an Education and Outreach Scientist at the Space Telescope Science Institute. She received her Ph.D. in planetary geology from the University of Colorado at Boulder in 2013. As a Postdoctoral Fellow, she worked with satellite stereo images to derive topographic models of locations that lack good elevation information, such as locations in Alaska and on Mars and Mercury. Dr. Marcucci is now part of the Office of Public Outreach at STScI, sharing the science of Hubble and Webb with the general public and astrophysics content as a member of the Universe of Learning, an Astrophysics-based STEM learning and literacy program funded through NASA SMD.

Dr. Farisa Morales is an active astrophysicist who hunts for planets at NASA’s Jet Propulsion Laboratory (JPL), and a professor at California State University, Northridge (CSUN) and Moorpark College. The summer she transferred from L.A. Mission Community College to UCLA, she participated in Caltech’s SURF internship program at NASA/JPL. While working at JPL as an academic part-timer, and raising her kids, Morales graduated with a Bachelor's degree in Astrophysics from UCLA, and with a Master’s degree in Physics from CSUN. Her work on the characterization of planetary debris disks at JPL with the Spitzer Space Telescope, evolved into her PhD dissertation project, and attained her PhD in Physics from USC. She also teaches astronomy and physics courses at Moorpark College and California State University-Northridge. Using space- and ground-based observatories, Morales studies stars surrounded by planetary debris systems—the dusty ring-like structures, home to colliding asteroids and sublimating comets, that circle stars like the Sun, and hint at planet formation processes, their architecture and composition. Morales also hunts for the planetary companions, stirring the dust, glowing in the infrared. She uses the powerful 10-meter Keck Observatory on Mauna Kea in Hawaii and the 5-meter Hale Telescope at Palomar Mountain in California. These telescopes have been adapted with optics that enable us to mask the star’s intense radiation and see the faint infrared light from the orbiting planets.

Dr. Hilke E. Schlichting is a Professor in Earth, Planetary and Space Sciences and in Physics and Astronomy at UCLA. Her research interests lie at the intersection of astrophysics and planetary sciences. In her work, she combine exoplanet-research with the study of our Solar System to take advantage of this powerful synergy to develop a comprehensive understanding of planet formation. Although she spends most of her time developing new theoretical models for planet formation, she has been an active user of the Hubble Space Telescope and, recently, the Stratospheric Observatory for Infrared Astronomy (SOFIA). Schlichting has been fascinated by space ever since she can remember. She considers herself fortunate to have had the chance to live in several different countries while growing up. She was born in Germany, spent her teenage years living in Japan and completed high school in the UK. She did her undergraduate studies at the University of Cambridge and received her PhD from Caltech. She was the recipient of NASA’s Hubble postdoctoral fellowship, joined MIT as professor in 2013, and moved to UCLA to join its faculty in 2016. Asteroid (9522) Schlichting was named after her in recognition of her work combining both observation and theory to estimate the Kuiper belt population. She thinks the best part of her job is that she has to learn something new every day, and that she gets to collaborate with scientists from all over the world.