Remote sensing of venusian seismic activity with a small spacecraft, the VAMOS mission concept

A numerical simulation of the upper atmosphere of Venus is carried out with an improved version of the Institut Pierre-Simon Laplace (IPSL) full-physics Venus General Circulation Model (GCM). This simulation reveals the organization of the atmospheric circulation at an altitude above 80 km in unprecedented detail. Converging flow towards the antisolar point results in supersonic wind speeds and generates a shock-like feature past the terminator at altitudes above 110 km. This shock-like feature greatly decreases nightside thermospheric wind speeds, favoring atmospheric variability on a hourly timescale in the nightside of the thermosphere. A ∼5-day period Kelvin wave originating in the cloud deck is found to substantially impact the Venusian upper atmosphere circulation. As the Kelvin wave impacts the nightside, the poleward meridional circulation is enhanced. Consequently, recombined molecular oxygen is periodically ejected to high latitudes, explaining the characteristics of the various observations of oxygen nightglow at 1.27 μm. An analysis of the simulated 1.27 μm oxygen nightglow shows that it is not necessarily a good tracer of the upper atmospheric dynamics, since contributions from chemical processes and vertical transport often prevail over horizontal transport. Moreover, dayside atomic oxygen abundances also vary periodically as the Kelvin wave momentarily decreases horizontal wind speeds and enhances atomic oxygen abundances, explaining the observations of EUV oxygen dayglow. Despite the nitrogen chemistry not being currently included in the IPSL Venus GCM, the apparent maximum NO nightglow shifted towards the morning terminator might be explained by the simulated structure of winds.

show abstract

“…for detecting seismic waves from remote observations and assess if Venus is geologically active in the present day (Didion et al, 2018).…”

Section: Introductionmentioning

confidence: 99%

Venus’ upper atmosphere revealed by a GCM: I. Structure and variability of the circulation

Navarro

Gilli

Schubert

et al. 2021

Icarus

View full text Add to dashboard Cite

show abstract

“…This type of mission will also benefit greatly from synergistic operation with an orbiter, which can provide planetary-scale context to local observations. One possible orbiter that performs seismology with a global context is the Venus Airglow Measurements and Orbiter for Seismicity (VAMOS) concept [48], [49]. Our initial results show tremendous promise-further development of this novel technology will enable the study of the interior structure of planetary bodies without landing on them.…”

Section: Discussionmentioning

confidence: 99%

Aerial Seismology Using Balloon-Based Barometers

Krishnamoorthy

Kassarian

Martire

et al. 2019

IEEE Trans. Geosci. Remote Sensing

Self Cite

View full text Add to dashboard Cite

Seismology on Venus has long eluded planetary scientists due to extreme temperature and pressure conditions on its surface, which most electronics cannot withstand for mission durations required for ground-based seismic studies. We show that infrasonic (low-frequency) pressure fluctuations, generated as a result of ground motion, produced by an artificial seismic source known as a seismic hammer, and recorded using sensitive microbarometers deployed on a tethered balloon, are able to replicate the frequency content of ground motion. We also show that weak, artificial seismic activity thus produced may be geolocated by using multiple airborne barometers. The success of this technique paves the way for balloon-based aeroseismology, leading to a potentially revolutionary method to perform seismic studies from a remote airborne station on the earth and solar system objects with substantial atmospheres such as Venus and Titan.

show abstract

“…Other instruments such as inertial measurement units and anemometers can also help disambiguate pressure fluctuations driven by balloon motion or local wind gusts from those generated by geophysical sources. With orbiter-based airglow monitoring, as suggested by Stevenson et al (2015) and formulated by Didion et al (2018), a single balloon monitoring seismic activity on Venus can also receive global context, especially for earthquakes larger than approximately M w 5. Thus, a single balloon can serve as a valuable pathfinder for detailed investigations using networks of balloons (Cutts et al, 2021) or landed seismometers in the future.…”

Section: Significant Demonstrations On Earthmentioning

confidence: 99%

A “Floatilla” of Airborne Seismometers for Venus

Krishnamoorthy

Bowman

2023

Geophysical Research Letters

Self Cite

View full text Add to dashboard Cite

The internal structure of a planetary body results from conditions in the early solar system followed by billions of years of geological evolution since then. Thus, studying and comparing the internal structures of planetary bodies offers a glimpse into the formation of the solar system itself. Seismology has proven to be one of the most effective tools to study planetary interiors for rocky bodies. This is because seismic waves generated by tectonic and volcanic activity interact with the solid planet, allowing for the determination of its internal structure.Seismology on global scales is a "wait and watch" science-thousands of seismometers deployed as part of vast networks on Earth passively record ground motion to detect and study seismic waves. Seismometers deployed by the Apollo missions on the Moon remained active for several years and recorded hundreds of moonquakes (Nunn et al., 2020). Similarly on Mars, the intrepid InSight lander lay in wait for several months for the first detection of a marsquake, but has since then detected over 1300 events, of which the larger ones have helped determine the size of the planet's core (Stähler et al., 2021). These long-duration seismic recordings have revolutionized our understanding of the Earth and its neighborhood. We now have a detailed map of Earth's interior, and know that Mars and the Moon are devoid of large-scale plate tectonics, but still currently seismically active. We know the layered structure of each of these bodies, the sizes of their cores, and the composition of their crusts.Venus is considered Earth's twin, but waiting and watching from its surface is easier said than done. Flybys from the Mariner missions discovered that the surface of Venus was inhospitably hot (>460°C) and dense (>90 atmospheres) (Barath et al., 1963), which was also confirmed by in-situ measurements by the Soviet Venera landers (Keldysh, 1977). The current record for longest survival time on the surface of Venus is held by the Venera-13 lander at 127 min (National Aeronautics and Space Administration (NASA), 2022), a time span that is much too short for conducting meaningful seismic recordings. Thus, the interior structure of Venus remains

show abstract

Remote sensing of venusian seismic activity with a small spacecraft, the VAMOS mission concept

Cited by 9 publications

References 29 publications

Venus’ upper atmosphere revealed by a GCM: I. Structure and variability of the circulation

Venus’ upper atmosphere revealed by a GCM: I. Structure and variability of the circulation

Aerial Seismology Using Balloon-Based Barometers

A “Floatilla” of Airborne Seismometers for Venus

Contact Info

Product

Resources

About