We consider a data assimilation technique for coupled ionospheric and thermospheric dynamics. The Global Ionosphere-Thermosphere Model (GITM) is used to simulate the ionospheric and thermospheric dynamics, and evaluate the performance of the data assimilation scheme that estimates the ion densities and flow speeds. This estimation technique is based on the state dependent Riccati equation (SDRE...

The sun is the primary driver of terrestrial atmospheric phenomena and energy source for the earth. It emits radiation over a large energy band and ejects highly energetic plasma fluxes of charged particles into space. The sun is an active star that (i) goes through a 12-year maximum-minimum emission cycle, (ii) has huge, non-periodic eruptions in solar flares and coronal mass ejections, and (i...

Exactly 130 years passed between the discovery by Isaac Newton that white light was composed of colors [1] and the discovery of ultraviolet radiation by Johann Wilhelm Ritter, a German electro chemist, in 1801. We now understand that ultraviolet radiation, although representing <2% of the total number of photons that reach the surface of present-day Earth, has had an important role in the evolu...

Introduction In the broad context of planetary science, Mars represents an important transition between the outer volatile-rich, more oxidised regions of the accretion zone of the terrestrial bodies (asteroid belt) and the inner, more refractory and less oxidised regions from which Earth, Venus and Mercury accreted. Its size, the degree of internal activity, the age of its surface features, and...

Aqua is a major satellite mission of the Earth Observing System (EOS), an international program centered at the U.S. National Aeronautics and Space Administration (NASA). The Aqua satellite carries six distinct earth-observing instruments to measure numerous aspects of earth’s atmosphere, land, oceans, biosphere, and cryosphere, with a concentration on water in the earth system. Launched on May...

Introduction: The idea of erosion of planetary atmosphere by giant impact was introduced by early works of Arrhenius et al. [1], Benlow and Meaows[2], Ringwood [3] and Cameron [4]. This idea was further expanded by other researchers to study the blow-off of atmosphere by other mechanisms due to the impactor [5-7]. Ahrens [8] described the degree of atmosphere erosion due to the surface wave ind...

GNSS, InSAR and LIDAR are identified as important techniques when it comes to monitoring and remote sensing of our planet Earth and its atmosphere. In fact, these techniques can be considered as key elements of the Global Geodetic Observing System. Examples of applications are: environmental monitoring; volcano monitoring, land slides, tectonic motion, deforming structures, atmosphere modeling,...

Introduction: Measurements of the martian atmosphere have experienced rapid growth during the past decade. As on Earth, remote sensing from orbit offers the advantage of nearly continuous, global coverage and a host of instruments have been employed for this purpose, including cameras [the Mars Orbiter Camera (MOC) and the Mars Color Imager (MARCI)] and infrared sounders [the Thermal Emission S...

Despite decades of efforts aimed at unraveling its origin, the terrestrial atmosphere is still considered to be one of the most puzzling enigmas in earth sciences. Remote observations will provide information on the atmospheres of extra-solar planets, some of these may prove to be hospitable for life. Understanding the origin of Earth’s atmosphere thus improves our knowledge of the sources and ...

Ancient Mars had liquid water on its surface and a CO2-rich atmosphere. Despite the implication that massive carbonate deposits should have formed, these have not been detected. On the basis of fundamental chemical and physical principles, we propose that climatic conditions enabling the existence of liquid water were maintained by appreciable atmospheric concentrations of volcanically degassed...