Think back. Where were you a year ago? Did you accomplish everything you planned over the last year? Some?
Around a year ago NASA’s spacecraft MAVEN (Mars Atmosphere and Volatile Evolution) began a 663, 049, 728 kilometer journey. (more or less) Maven was launched aboard an Atlas V launch vehicle, coasting in Earth’s orbit until it could be launched into a heliocentric Mars transit orbit. Yesterday at around 10:30, MAVEN arrived at her destination and was inserted into orbit 6200 km above the planet Mars surface.
The MAVEN mission has many scientific instruments on board to help her in her assigned tasks of unveiling the why and how Mars no longer is some lush planet but instead has what appears to be dry riverbeds with sediment that is indicative of water &/or heavy water. The supposition is that Mars once had a dense enough atmosphere, a magnetic field, and was even warmer (currently about 20 degrees Celsius at high noon near the equator and about -153 Celsius by the poles) but then lost that atmosphere to space. The planet core cooled, the magnetic field decayed and the water dried up; evaporating and falling prey to the solar wind – first the H2O then the heavier H3O all which left sediments.
The evolution of the climate of Mars is the task at hand. The hope is that by measuring the rate the current loss of atmospheric gases and other relevant processes that scientists can infer how the atmosphere evolved.
But MAVEN didn’t travel all that way without a list of her primary scientific objectives. They are;
1)Determine the role that loss of volatiles to space from the Martian atmosphere has played through time.
2)Determine the current state of the upper atmosphere, ionosphere, and interactions with the solar wind.
3) Determine current escape rates of neutral gases and ions to space and the processes controlling them.
4)Determine the ratios of stable isotopes in the Martian atmosphere.
As hard as the trip was, the long 663 million kilometers, the real work begins now. MAVEN will conduct all of its observations from the upper atmosphere of Mars. Flight controllers in Colorado will spend the next six weeks adjusting MAVEN’s altitude and checking its science instruments and then she will start probing. Thus far Mars has yielded any proof that it once harbored life, but it is hypothesized that microbial life existed in the early wet world that Mars was.
It is the intention of MAVEN to study the upper atmosphere and ionosphere as wel as the solar wind from a highly elliptical orbit over a one Earth year period. While much of it will be spent in the heights of the atmosphere there will be five “deep dips” to 150 kilometers. The instruments onboard that will provide the data which it is hoped will uncover the how, why, & when of this Martian puzzle are (and it is a long list!); A Particle and Field Package, Solar Wind Electron Analyzer (SWEA) - measures solar wind and ionosphere electrons, Solar Wind Ion Analyzer (SWIA) - measures solar wind and magnetosheath ion density and velocity, SupraThermal And Thermal Ion Composition (STATIC) - measures thermal ions to moderate-energy escaping ions, Solar Energetic Particle (SEP) - determines the impact of SEPs on the upper atmosphere, Langmuir Probe and Waves (LPW) - determines ionosphere properties and wave heating of escaping ions and solar extreme ultraviolet (EUV) input to atmosphere, Magnetometer (MAG) - measures interplanetary solar wind and ionosphere magnetic fields & Remote Sensing (RS) Package,Imaging Ultraviolet Spectrometer (IUVS) - measures global characteristics of the upper atmosphere and ionosphere, Neutral Gas and an Ion Mass Spectrometer (NGIMS) Package
that Measures the composition and isotopes of neutral gases and ions.
Sunday was a real nail-biter as MAVEN was clocked doing more than 16,000 kph when it hit the brakes (no, it didn’t see a space-cop) for an orbital insertion (a 30 minute process) followed by the twelve minute lag for signals to cross the 222 million kilometers and then a huge sigh of relief.
Maven joins three spacecraft already circling Mars, two American and one European. But three isn’t a crowd and neither should four be when they are joined by India's first interplanetary probe, Mangalyaan, which reaches Mars in two days and also will aim for orbit.
This is NASA's 21st shot at Mars and the first since the Curiosity rover landed on the red planet in 2012. Just this month, Curiosity arrived at its prime science target, a mountain named Sharp, ripe for drilling. The Opportunity rover is also still active a decade after landing.
All these robotic scouts are making it safer and paving the way for the human explorers that NASA hopes to send in the 2030s.
See? We already have colonists on Mars! Cool, right?
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