OrbitalHub

Wikipedia dicit:

Features on Mars that resemble dry riverbeds and the discovery of minerals that form in the presence of water indicate that Mars once had a dense enough atmosphere and was warm enough for liquid water to flow on the surface. However, that thick atmosphere was somehow lost to space. Scientists suspect that over millions of years, Mars lost 99% of its atmosphere as the planet’s core cooled and its magnetic field decayed, allowing the solar wind to sweep away most of the water and volatile compounds that the atmosphere once contained.

The goal of MAVEN is to determine the history of the loss of atmospheric gases to space, providing answers about Martian climate evolution. By measuring the rate with which the atmosphere is currently escaping to space and gathering enough information about the relevant processes, scientists will be able to infer how the planet’s atmosphere evolved over time.

Video credit: NASA Goddard

NASA dicit:

Mars’ nightside atmosphere glows and pulsates in this data animation from MAVEN spacecraft observations. Green-to-white false color shows the enhanced brightenings on Mars’ ultraviolet “nightglow” measured by MAVEN’s Imaging UltraViolet Spectrograph at about 70 kilometers (approximately 40 miles) altitude. A simulated view of the Mars globe is added digitally for context, with ice caps visible at the poles. Three nightglow brightenings occur over one Mars rotation, the first much brighter than the other two. All three brightenings occur shortly after sunset, appearing on the left of this view of the night side of the planet. The pulsations are caused by downwards winds which enhance the chemical reaction creating nitric oxide which causes the glow. Months of data were averaged to identify these patterns, indicating they repeat nightly.

Video credit: NASA/MAVEN/Goddard Space Flight Center/CU/LASP

Wikipedia dicit:

NASA’s MAVEN (Mars Atmosphere and Volatile Evolution) spacecraft has discovered “layers” and “rifts” in the electrically charged part of the upper atmosphere (the ionosphere) of Mars. The phenomenon is very common at Earth and causes unpredictable disruptions to radio communications. However, we do not fully understand them because they form at altitudes that are very difficult to explore at Earth. The unexpected discovery by MAVEN shows that Mars is a unique laboratory to explore and better understand this highly disruptive phenomenon.

Video credit: NASA’s Goddard Space Flight Center/James Tralie (ADNET): Lead Producer, Lead Editor, Narrator/Bailee DesRocher (USRA): Lead Animator/Michael Lentz (USRA): Art Director/Jonathan North (USRA): Animator/Krystofer Kim (USRA): Animator/Jacquelyn DeMink (USRA): Animator/Bruce Jakosky (LASP): Scientist/Glyn Collinson (Catholic University of America): Scientist/Aaron E. Lepsch (ADNET): Technical Support

NASA dicit:

MAVEN is the first spacecraft specifically designed to study the Mars upper atmosphere, in order to better understand the evolution of its climate. By measuring windspeed and direction near the top of the atmosphere, MAVEN has discovered that high-altitude wind currents are being disturbed by terrain features far below. This unexpected and surprising finding means that MAVEN can sense the presence of mountains and valleys on the surface of Mars while skimming the edge of space.

Video Credit: NASA/Goddard/MAVEN/CU Boulder/University of Michigan/Dan Gallagher (USRA): Producer/Greg Shirah (NASA/GSFC): Lead Data Visualizer/Jonathan North (USRA): Lead Animator/Ernie Wright (USRA): Visualizer/Horace Mitchell (NASA/GSFC): Visualizer/Michael Lentz (USRA): Animator/Walt Feimer (KBRwyle): Animator/Chris Smith (USRA): Animator/John/Blackwell (LPI): Animator/Dan Gallagher (USRA): Narrator/Michael Lentz (USRA): Art Director/Mehdi Benna (UMBC): Lead Scientist/Kali Roeten (UM): Scientist/Paul Mahaffy (NASA/GSFC): Support/Bruce Jakosky (LASP): Principal Investigator/Aaron E. Lepsch (ADNET): Technical Support