ASU astronomers advance NASA’s Pandora mission to study planetary atmospheres
Artist’s concept of NASA’s Pandora mission, which will help scientists untangle the signals from exoplanets' atmospheres and their stars. Photo courtesy NASA's Goddard Space Flight Center/Conceptual Image Lab
NASA's recent January launch of the Pandora SmallSat mission is set to explore one of exoplanet science's greatest challenges: distinguishing the true atmospheric signals of distant worlds from the ever-changing surfaces of their host stars.
Traditional observations have struggled due to stellar variability, which introduces spectral signals from the star to what otherwise would be planetary, complicating the detection of key atmospheric components such as water and methane.
The mission is designed to study both exoplanets and their host stars simultaneously. Pandora SmallSat will observe 20 exoplanet targets over the coming year using cutting-edge near-infrared and optical spectrometry. By dedicating dozens of hours per visit to each planet, the small satellite will precisely characterize both planetary and stellar properties, reducing the chances of false positives and advancing the search for worlds beyond our solar system.
The first science paper of the mission, which modeled the expected observational capabilities of Pandora ahead of the mission's launch, was recently published in The Astronomical Journal. The paper was led by Yoav Rotman, a PhD student in Arizona State University’s School of Earth and Space Exploration, during his time as a Pandora science intern at the Lawrence Livermore National Laboratory's Space Science Institute. The paper includes ASU co-authors Luis Welbanks and Michael Line.
“Pandora will unlock a new level of understanding of how these planets and their stars interact and evolve,” said Rotman, a current Pandora science team contributor.
Rotman modeled the mission's expected observations to assess its scientific potential, leading a team to predict what the Pandora mission will be able to measure in the atmospheres of these distant worlds. The models showed that, when combined with data from NASA’s James Webb Space Telescope, Pandora’s observations will yield even stronger results than either instrument alone.
-
Figure 1. The transit method for transmission spectroscopy, used by telescopes such as the James Webb Space Telescope, measures the combined light from a star and planet during a transit and compares it with observations of the star alone. The difference reveals the spectrum of the planet's atmosphere. However, variability in the host star can contaminate these measurements, making planetary signals more difficult to interpret. Pandora is designed to correct for this effect by observing both the star and planet simultaneously.
Photo courtesy LLNL/ASU/Y.Rotman
-
Figure 2. This graph shows the expected precision from 1-20 transits observed with Pandora (blue), a single transit observation with the James Webb Space Telescope (JWST) (yellow), and a combination of the two (red). A lower value on the Y-axis indicates a more precise the estimate of the atmosphere’s H2O abundance. By combining Pandora and JWST observations, the team can nearly double the precision compared with data collected from a single transit of JWST.
Photo courtesy LLNL/ASU/Y.Rotman
-
The Pandora team is photographed with engineering hardware for the telescope. (From left) Scott Pitts, Lance Simms, Jeff Klingmann, Maricris Schneider, Owen Alford, Aaron Peer, Phillip Rittmuller, Ariana Garcia, Richinder Rehal, Tara Grice, Hilary Johnson, Colin Averill, Michael Wong, Ryan Fellini and Jordan Karburn. Not pictured: Pete Supsinskas, Livermore project manager for Pandora.
Photo courtesy LLNL/ASU/Y.Rotman
Rotman and Welbanks also contributed to a companion paper recently published in the Astronomical Journal that evaluated how well the upcoming NASA Pandora SmallSat mission will measure the properties of the host stars and correct contamination from stellar activity in exoplanet transmission spectroscopy.
Together, these studies highlight how Pandora will help researchers more accurately characterize distant worlds while complementing observations from other major observatories.
"Reliably measuring the properties and compositions of these distant worlds, and the stars they orbit, will require joint efforts that leverage multiple space- and ground-based telescopes," said Welbanks, leader of the Exoteric Lab at ASU.
"Our exoplanet groups at ASU are hard at work developing the methods to bring these tools together, and Pandora will be a key player in this new landscape."
More about Pandora
Pandora is a small satellite that was selected as part of NASA’s inaugural call for Pioneer mission concepts in 2021. It’s designed to study the atmospheres of exoplanets, or worlds beyond our solar system, and the activity of their host stars with long-duration multiwavelength observations. The project is a collaboration between NASA’s Goddard Space Flight Center, Lawrence Livermore National Laboratory, NASA’s Ames Research Center and a host of other institutions.
Pandora is led by NASA’s Goddard Space Flight Center. Lawrence Livermore National Laboratory provides the mission’s project management and engineering. Pandora’s telescope was manufactured by Corning and developed collaboratively with Livermore, which also developed the imaging detector assemblies, the mission’s control electronics, and all supporting thermal and mechanical subsystems. The infrared sensor was provided by NASA Goddard. Blue Canyon Technologies provided the bus and is performing spacecraft assembly, integration and environmental testing. NASA’s Ames Research Center in California’s Silicon Valley performs the mission’s data processing. Pandora’s mission operations center is located at the University of Arizona, and a host of additional universities support the science team. Pandora’s science data is stored and accessible at the NASA Exoplanet Archive, which is operated at IPAC by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program.