MAVEN is scheduled for launch on November 18, 2013, arriving at Mars on September 22, 2014. Image Courtesy MAVENThe Mars Atmosphere and Volatile Evolution, or MAVEN, mission will orbit Mars to seek answers to fundamental mysteries that scientists have yet to solve regarding the origin of the Martian planet's atmosphere and climate. How did the Sun strip the planet of its ability to harbor microbial life forms? What happened to the abundant water and thick atmosphere that were once present on Mars? Finding the answers to these questions will be MAVEN's mission: to study the atmosphere of Mars by measuring the loss of Martian atmospheric gas to space and figure out how this had affected the planet's climate over time to create what it is now - barren, desert-like and cold. Dr. Bruce Jakosky, University of Colorado's Associate Director for Science in the Laboratory for Atmospheric and Space Physics and MAVEN's principal investigator, provided me with some excellent insight on what this exploratory Mars mission hopes to achieve in the months before the launch date on Nov. 18 and what MAVEN means for the future of human space exploration.
The MAVEN mission takes 10 months to reach the red planet, and is scheduled to reach Mars orbit around Sept. 2014. Its one-year mission will place the spacecraft in near-Marselliptical orbit to test the planet's upper (highest orbital point at 3728 m./6000 km. from the surface) and lower atmosphere (closest orbital point at 93 m./150 km. above the surface). MAVEN's main scientific tasks will be to sample the gas and ion composition of Mars's upper atmosphere and to perform comprehensive ultraviolet imaging of the entire planet from it's higher orbital position. According to the MAVEN mission website, there are four main objectives of MAVEN's mission: to determine the role that the loss of volatiles from the Mars atmosphere to space has played through time, to determine the current state of the upper atmosphere, ionosphere, and interactions with the solar wind, to determine the current rates of escape of neutral gases and ions to space and the processes controlling them, and to determine the ratios of stable isotopes that will tell Mars' history of loss through time.
Three groups of instruments will handle the delicate work of measuring the composition of the planet's atmosphere. MAVEN will carry a total of eight sensors that will perform the complex atmospheric measurements of the Martian atmosphere:
Magnetometer Neutral Gas and Ion Mass Spectrometer Langmuir Probe and Waves Imaging Ultraviolet Spectrometer Solar Wind Electron Analyzer Solar Wind Ion Analyzer Solar Energetic Particles SupraThermal And Thermal Ion Composition
Six instruments in the Particles and Fields Package (PFP) will measure the solar wind and the ionosphere of the planet. The Remote Sensing Package will measure global characteristics of the upper atmosphere and ionosphere, and the Neutral Gas and Ion Mass Spectrometer (NGIMS), will measure the composition and isotopes of neutrals and ions.
One fascinating fact about the MAVEN mission is that it is solar powered! The design of the solar panels builds on the legacy of NASA's Mars Exploration Program. According to Weyman Weems, MAVEN solar array engineer at Lockheed Martin Space Systems, MAVEN's solar arrays are deployed during the mission in the following manner:
The two solar array wings, which are folded up for launch, are deployed shortly after separation from the launch vehicle. Once deployed, more than 2000 solar cells supply all of the electrical power needs for the journey to Mars, and to power the scientific instruments upon arrival. The wings, constructed from a lightweight composite and aluminum honeycomb panels and high efficiency cells, amount to approximately 320 square feet of area, with a wingspan of 37 feet across, and are capable of surviving daily temperature swings of -300 deg. F to +250 deg. F. The "gull-wing" shape provides the aerostability during periodic dips into the Martian atmosphere.
Here are the specifications on the MAVEN spacecraft itself:
* Length: 37.5 feet (11.4 meters) * Spacecraft Dry Mass: 1991 pounds max (903 kilograms) * Wet (Fueled) Mass at Launch: 5622 pounds max (2550 kilograms) * Power: 1135 watts (when Mars is furthest from the Sun)
Below is my Q&A with Dr. Bruce Jakosky, MAVEN's principal investigator, Associate Director for Science in the Laboratory for Atmospheric and Space Physics at the University of Colorado about how MAVEN's mission will add to our understanding of Mars in terms of studying the planet's atmosphere and investigating whether any life forms existed, or do exist in the Martian landscape.
Michael Venables: How will the launch of the MAVEN spacecraft in November contribute towards our understanding of the challenges of the Mars atmosphere?
Bruce Jakosky: The goal of the MAVEN mission is to better understand the history of the Martian atmosphere - why did it change from an earlier, warmer and wetter environment to the colder and drier one we see today? Where did the water go? Where did the CO2 go? These gases can either go down and become locked up in the crust, or they can go up and be lost to space out the top of the atmosphere. We have evidence that each process has occurred, but we don't have enough information to know which was the most important set of processes. MAVEN will determine the importance of the role of loss to space. These issues get at the fundamental question of how did the Mars atmosphere change over time. And that, really, is the larger question of what controls the Mars climate, and how did the "habitability" of Mars by microbes change over time.
Venables: How will understanding the atmosphere of Mars help in possible robotic missions to gather surface samples with a Mars ascent vehicle?
Jakosky: One of the most important questions about Mars is whether there is (or ever was) life there. This is a hard question to answer, and the answer when we get it does not stand in isolation. In order to know what it means if we find life, or if we look and don't find life, we need to understand the conditions that controlled the planet's environment and may have allowed Mars to have life. Certainly, understanding the history of the climate and of the availability of things like water and carbon dioxide is a fundamental part of that. Without knowing these, it's hard to know what the broader significance of a detection of life (or of a non-detection) would be. In addition, there's a direct contribution. One of the ways in which we detect evidence for life on Earth is in the ratio the abundances of stable isotopes. For example, we measure the ratio of the abundance of O atoms that have an extra neutron in their nucleus to the abundance of those without. That's referred to as the ratio of 18O/16O, where the number is the atomic mass of the nucleus. The chemical reactions that are involved with life change this ratio. On Earth, we look for that changed ratio as an indication that life had existed, even if we can't identify fossil organisms. On Mars, the processes involved in loss of gas to space also can affect that ratio. Thus, we can't use it to determine whether life had been there unless we know the "non-biological" ways in which that ratio changes. One aspect of MAVEN is to determine how these different isotopes are lost to space and how the escape process has changed that ratio over time.
The importance of the MAVEN mission can't be understated, and there are two important forces of government-private sector collaboration and of important scientific discovery at work. First, MAVEN is the first Mars mission managed by the Goddard Space Flight Center. If successful, and all bets are that it will be, it points to the continued success of NASA's ongoing collaboration on space research and exploration missions with the private sector related to the Mars Exploration Program. The organizations involved in the MAVEN project highlight the deep ties between NASA and the private sector. The University of Colorado is building two science instruments, will conduct science operations, and leads efforts of education and public outreach. NASA's Goddard Space Flight Center manages the project and is building two of the science instruments. U.C. Berkeley's Space Sciences Laboratory is building four science instruments for the mission. Lockheed Martin is building the spacecraft and will perform mission operations. NASA's Jet Propulsion Laboratory is managing the entire project via its Mars Program Office as well as handling data-relay telecommunications hardware and operations, navigation support, and Deep Space Network operations.
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