Ana-Catalina Plesa

German Aerospace Center (DLR) | DLR · Department of Planetary Physics

In this chapter, we focus on the long-term evolution of the atmosphere of Venus, and how it has been affected by interior/exterior cycles. The formation and evolution of Venus's atmosphere, leading to the present-day surface conditions, remain hotly debated and involve questions that tie into many disciplines. Here, we explore the mechanisms that s...

Martian basalts identified by rover in-situ analyses and the study of meteorites represent a direct link to the melting process in the planet’s interior and can be used to reconstruct the composition of the mantle and estimate its temperature. Experimentally calibrated numerical models are powerful tools to systematically search for the mantle comp...

Die Analyse von seismischen Wellen bildet die Grundlage für unser heutiges Verständnis vom Aufbau der Erde und des Mondes. Mehr als 100 Jahre nach den ersten Messungen der Dicke der Erdkruste und des Radius des Erdkerns ließen sich diese Größen erstmals auch für den Mars bestimmen, mithilfe des europäischen Seismometers SEIS der NASA-Mission InSigh...

Plain Language Summary The InSight mission operating on Mars is currently monitoring the planet's seismic activity. The recorded marsquakes can be used to obtain information on Mars' internal composition. However, the interpretation of these observations requires knowledge of the physical properties of the minerals expected to compose the Martian m...

Deltas have been long considered a constraining element to reconstruct the water level of an ancient ocean that may have once occupied the northern lowlands of Mars, and just recently this hypothesis started to be challenged. We investigate this hypothesis and present a global inventory of fan shaped features showing typical deltaic traits across t...

Clues to a planet’s geologic history are contained in its interior structure, particularly its core. We detected reflections of seismic waves from the core-mantle boundary of Mars using InSight seismic data and inverted these together with geodetic data to constrain the radius of the liquid metal core to 1830 ± 40 kilometers. The large core implies...

A planet’s crust bears witness to the history of planetary formation and evolution, but for Mars, no absolute measurement of crustal thickness has been available. Here, we determine the structure of the crust beneath the InSight landing site on Mars using both marsquake recordings and the ambient wavefield. By analyzing seismic phases that are refl...

We use a large data set of 3D thermal evolution models to predict the distribution of present-day seismic velocities in the Martian interior. Our models show a difference between maximum and minimum S-wave velocity of up to 10% either below the crust, where thermal variations are largest, or at the depth of the olivine to wadsleyite phase transitio...

The icy moons of our Solar System, such as the Saturnian moon Enceladus and the Jovian moon Europa, are scientifically highly interesting targets for future space missions, since they are potentially hosting extraterrestrial life in their oceans below an icy crust. Moreover, the exploration of these icy moons will enhance our understanding of the e...

In Earth's deep continental subsurface, where groundwaters are often isolated for >106 to 109 years, energy released by radionuclides within rock produces oxidants and reductants that drive metabolisms of non-photosynthetic microorganisms. Similar processes could support past and present life in the martian subsurface. Sulfate-reducing microorganis...

The Martian mantle probably experienced an early global magma ocean stage. The crystallization and the fractionation and overturn of such a magma ocean likely led to the formation of a compositionally distinct layer at the bottom of the mantle. This layer would have been heavily enriched in iron and in heat-producing elements (HPE). The significant...

Large-scale numerical simulations of planetary interiors require dedicated visualization algorithms that are able to efficiently extract a large amount of information in an interactive and user-friendly way. Here we present a software framework for the visualization of mantle convection data. This framework combines real-time volume rendering, path...

At last year’s AGU, the first author presented his and his co-authors' work as narrated by an animated cartoon representation of himself. Since rocks in the crust of a planet can flow on long timescales with enough heat or pressure, empty pore spaces and fractures in rock can close deep into the crust. The thickness of the porous upper layer of the...

The ancient martian dynamo is mysterious in both spatial and temporal features. First, strong crustal magnetic fields are concentrated in the southern hemisphere, whereas the crustal magnetic fields in the northern hemisphere are mostly weak. Second, the ancient martian dynamo appears to have been active both before and after the Late Heavy Bombard...

Impact cratering events and collisions of large bodies are a fundamental process during the formation of the solar system and result in the generation of huge quantities of impact-induced melt that affects the further evolution and appearance of the target body. Traditionally, melt quantities are estimated by semi-analytical models or parameterized...

Although Venus is similar to Earth in terms of size and composition, basic parameters such as the size and state of its core are unknown or uncertain. For a better understanding of the interior structure and thermal state of Venus important information can be gained with the moment of inertia factor (MOIF), tidal Love number, k2 and the tidal phase...

The NASA InSight mission on Mars, equipped with the seismometer SEIS, is currently monitoring the seismic activity of the planet, and several recorded marsquakes have been exploited to gain information about Mars’ internal structure. Interpretation of these seismological observations in terms of composition and mineralogy requires the knowledge of...

The surface of Venus is dominated by volcanic materials and hundreds of volcanic edifices can be found across the planet [1]. The largest among these are the so-called coronae, i.e., circular to elongated features surrounded by concentric fractures that reach diameters of hundreds of kilometers, and large shield volcanoes (100-1000 km diameter); in...

The measurements of tidal deformation provide an important constraint on the interior structure of celestial bodies. In particular, the tidal Love numbers (k2, h2, l2) and the tidal lagging are sensitive to a moon’s or planet’s elastic and rheological parameters, density and temperature profiles of the mantle, and the state of the core. Constrainin...

The martian surface is predominantly covered by FeO-rich basalts and their alteration products. Several samples, either analyzed in situ by rovers or recovered as meteorites, might represent primitive (i.e. near-primary) basaltic melts that can shed light on the mineralogy, the bulk composition, and the temperature of their mantle sources. We recen...

InSight is the first planetary mission dedicated to exploring the whole interior of a planet using geophysical methods, specifically seismology and geodesy. To this end, we observed seismic waves of distant marsquakes and inverted for interior models using differential travel times of phases reflected at the surface (PP, SS...) or the core mantle-b...

The early bombardment history of Mars may have drastically shaped its crustal evolution. Impact-induced melting of crustal and mantle materials leads to the formation of local and regional melt ponds, and the cumulative effects of the impact flux could result in widespread melting of the crust. To quantify impact-melt production, its provenance and...

Plain Language Summary On long timescales, and with enough heat or pressure, rocks in the crust of a planet can flow. This viscous deformation allows the empty pore spaces in a rock to close up. The history of the temperature at depth plays an important role in how deep one may expect porosity to exist. One can use a computational model to calculat...

Mars’s seismic activity and noise have been monitored since January 2019 by the seismometer of the InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) lander. At night, Mars is extremely quiet; seismic noise is about 500 times lower than Earth’s microseismic noise at periods between 4 s and 30 s. The recorded sei...

NASA’s InSight (Interior exploration using Seismic Investigations, Geodesy and Heat Transport) mission landed in Elysium Planitia on Mars on 26 November 2018. It aims to determine the interior structure, composition and thermal state of Mars, as well as constrain present-day seismicity and impact cratering rates. Such information is key to understa...