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MAVEN is a NASA spacecraft orbiting Mars to study the loss of that planet's atmospheric gases to space, providing insight into the history of the planet's climate and water.
The name is an acronym for Mars Atmosphere and Volatile Evolution while the word maven also denotes a person who has special knowledge or experience; an expert.
MAVEN was launched on an Atlas V rocket from Cape Canaveral Air Force Station, Florida, on 18 November 2013 UTC and went into orbit around Mars on 22 September 2014 UTC.
The mission is the first by NASA to study the Mars atmosphere. The probe is analyzing the planet's upper atmosphere and ionosphere to examine how and at what rate the solar wind is stripping away volatile compounds.
The principal investigator for the mission is Shannon Curry at the University of California, Berkeley. She took over from Bruce Jakosky of the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder, who proposed and led the mission until 2021. The project cost $582.5 million to build, launch, and operate through its two-year prime mission.
Proposed in 2006, the mission was the second of NASA's Mars Scout Program, which had previously yielded Phoenix. It was selected for development for flight in 2008.
On 2 August 2013, the MAVEN spacecraft arrived at Kennedy Space Center, in Florida to begin launch preparations.
On 1 October 2013, only seven weeks before launch, a government shutdown caused suspension of work for two days and initially threatened to force a 26-month postponement of the mission. With the spacecraft nominally scheduled to launch on 18 November 2013, a delay beyond 7 December 2013 would have caused MAVEN to miss the launch window as Mars moved too far out of alignment with the Earth.
However, two days later, on 3 October 2013, a public announcement was made that NASA had deemed the 2013 MAVEN launch so essential to ensuring future communication with current NASA assets on Mars -the rovers Opportunity and Curiosity- that emergency funding was authorized to restart spacecraft processing in preparation for an on-time launch.
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.
More information: NASA
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. The MAVEN mission's primary scientific objectives are:
-Measure the composition and structure of the upper atmosphere and ionosphere today, and determine the processes responsible for controlling them
-Measure the rate of loss of gas from the top of the atmosphere to space, and determine the processes responsible for controlling them
-Determine properties and characteristics that will allow us to extrapolate backwards in time to determine the integrated loss to space over the four-billion-year history recorded in the geological record.
MAVEN launched from the Cape Canaveral Air Force Station (CCAFS) on 18 November 2013, using an Atlas V 401 launch vehicle. It reached Mars on 22 September 2014, and was inserted into an elliptic orbit approximately 6,200 km by 150 km above the planet's surface.
In October 2014, as the spacecraft was being fine-tuned to start its primary science mission, the comet Siding Spring was also performing a close flyby of Mars. The researchers had to maneuver the craft to mitigate harmful effects of the comet, but while doing so, were able to observe the comet and perform measurements on the composition of expelled gases and dust.
On 16 November 2014, investigators completed MAVEN's commissioning activities and began its primary science mission, scheduled to last one year. During that time, MAVEN had observed a nearby comet, measured how volatile gases are swept away by solar wind, and performed four deep dips down to the border of the upper and lower atmospheres to better characterize the planet's entire upper atmosphere.
In June 2015, the science phase was extended through September 2016, allowing MAVEN to observe the Martian atmosphere through the entirety of the planet's seasons.
On 3 October 2016, MAVEN completed one full Martian year of scientific observations. It had been approved for an additional 2-year extended mission through September 2018. All spacecraft systems were still operating as expected.
In March 2017, MAVEN's investigators had to perform a previously unscheduled maneuver to avoid colliding with Phobos the following week.
On 5 April 2019, the navigation team completed a two-month aerobraking maneuver to lower MAVEN's orbit and enable it to better serve as a communications relay for current landers as well as the rover Perseverance. This new elliptic orbit is approximately 4,500 km by 130 km. With 6.6 orbits per Earth day, the lower orbit allows more frequent communication with rovers.
As of September 2020, the spacecraft is continuing its science mission as well, with all instruments still operating and with enough fuel to last at least until 2030.
On August 31, 2021, Shannon Curry became the Principal Investigator of the mission.
NASA became aware of failures in the MAVEN's inertia measurement units (IMU) in late 2021, necessary for the probe to maintain its orbit; having already moved from the main IMU to the backup one in 2017, they saw the backup ones showing signs of failure.
In February 2022, both IMUs had appeared to lost the ability to perform its measurement properly. After doing a heartbeat termination to restore the use of the backup IMU, NASA engineers set to reprogram MAVEN to use an all stellar mode using star positions to maintain its altitude, eliminating the reliance on the IMUs. This was put into place in April 2022 and completed by May 28, 2022, but during this period, MAVEN could not be used for scientific observations or to relay communications to Earth from the rovers Curiosity and Perseverance and the Insight lander. Reduced communication was handled by other Mars orbiters.
In 2014, MAVEN researchers detected widespread aurora throughout the planet, even close to the equator. Given the localized magnetic fields on Mars (as opposed to Earth's global magnetic field), aurora appear to form and distribute in different ways on Mars, creating what scientists call diffuse aurora.
The fortuitous arrival of MAVEN just before a flyby of the comet Siding Spring gave researchers a unique opportunity to observe both the comet itself as well as its interactions with the Martian atmosphere.
In 2017, results were published detailing the detection of metal ions in Mars's ionosphere. This is the first time metal ions have been detected in any planet's atmosphere other than Earth's. It was also noted that these ions behave and are distributed differently in the atmosphere of Mars given that the red planet has a much weaker magnetic field than our own.
In September 2017, NASA reported a temporary doubling of radiation levels on the surface of Mars, as well as an aurora 25 times brighter than any observed earlier. This occurred due to a massive, and unexpected, solar storm.
The observation provided insight into how changes in radiation levels might impact the planet's habitability, helping NASA researchers understand how to predict as well as mitigate effects on future human Mars explorers.
More information: NASA
as well as the world's premier space exploration agency,
and we are well served by politicians working
to keep it that way, instead of turning it
into a mere jobs program, or worse, cutting its budget.
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