Finding and characterizing small exoplanets transiting small stars naturally poses the question of their habitability. A major contributing factor to this might be stellar flares, originating from powerful magnetic reconnection events on the star. While too powerful flaring can erode or sterilize exoplanets’ atmospheres and diminish their habitability, a minimum flare frequency and energy might be required for the genesis of life around M-dwarfs in first place. Here, I will first highlight our TESS study of stellar flares and our search for exoplanets transiting these stars, linking our findings to prebiotic chemistry and ozone sterilization. We already identified thousands of flaring stars, including many young, rapidly rotating M-dwarfs, some showing superflares with over 30x brightness increase in white light. Further, I will discuss a particularly interesting, newly discovered system: a super-Earth and two sub-Neptunes transiting the bright and nearby M-dwarf TOI-270, which is optimally suited to study the 'missing link' between planets on either side of the radius gap. With upcoming TESS sectors, stellar flare studies and new exoplanet discoveries will ultimately aid in defining criteria for exoplanet habitability.
Katie Stack Morgan,
Mars 2020, NASA’s next flagship mission to Mars, will launch in July-August 2020 and will begin its mission on the martian surface in February 2021. Mars 2020 is seeking signs of past life in Jezero crater, the site of an ancient delta and crater lake. The Mars 2020 rover will also collect a diverse and compelling set of rock and soil samples for potential return to Earth by a future set of missions. This presentation will provide an overview of Mars 2020’s mission objectives, the geology of its landing site, and what we hope to learn from NASA’s next Mars mission.
Space weather, also known as solar weather, refers to the light, energy and particles that emitted from the sun. As NASA plans to send humans to Mars in the 2030s, it is important to understand how space weather environment will impact their journey and their residence at Mars. The Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft has been continuously observing the variability of solar irradiance, monitoring the upstream solar wind and interplanetary magnetic field conditions and measuring the fluxes of solar energetic particles since its arrival to Mars in September 2014. Combining spacecraft observations and numerical model results, we will discuss the impact of space weather events on the plasma environment of Mars and its atmospheric loss. Given the likely prevalence of ICME-like conditions earlier in the solar system history, ion loss during solar events in ancient times could have contributed significantly to the long-term evolution of the Mars atmosphere. In addition, I will give a brief overview of the ESCAPADE (Escape and Plasma Acceleration and Dynamics) mission, a recently selected Mars mission, and how it will help us to better understand the Martian response to space weather events.
The spins of planets, moons, and small bodies are not constant with time; they change in response to both external and internal forces on a variety of spatial and temporal scales. These changes can have important consequences for the geology of planetary bodies, including stirring up core dynamos, generating tectonic stresses, and altering the stability of water and other volatiles on the surface. In this talk, I will share several key results from my investigation of rotational dynamics across the solar system, including impact-induced wobbling of the Moon, and the evolution of Kuiper Belt objects like Pluto and (486958) Arrokoth.
Planetary systems are prevalent around main sequence stars but little is known about their fate beyond the main sequence stage. In this talk, I will show different evidence that planetary systems can be present and active around white dwarfs. I will also discuss new opportunities to study planetary systems around white dwarfs from current and future facilities, including Gaia, TESS, and JWST.
Ariel Graykowski and Francisco Spaulding-Astudillo,
Investigation of the Fragments of Split Comet 73P: In this talk, I will discuss cometary fragmentation in general as well as a case study of split comet 73P/Schwassmann-Wachmann 3. 73P has been observed to fragment on several occasions, however the cause of its fragmentation was poorly understood. We analyzed unpublished archival Hubble Space Telescope data in order to understand its fragmentation mechanism. From this work, we rule out rotational instability as potential breakup mechanism for 73P and provide a deeper analysis of its fragmentation evolution. The Effect of Moisture on Cloud Formation in Terrestrial Planetary Atmospheres: We examine a one-dimensional radiative convective equilibrium (1D-RCE) model, with water vapor and cloud feedbacks. The moisture parameters of the 1D-RCE are modified to enable variation of the saturation vapor pressure. We begin with an Earth-like aquaplanet with an atmosphere made of the present-day mix of dry components and share some initial results.