MAVEN Deep Dip

By measuring windspeed and direction in the Mars upper atmosphere, MAVEN has discovered that high-altitude wind currents are being disturbed by terrain features far below.Credit: NASA/Goddard/MAVEN/CU Boulder/University of MichiganUniversal Production Music: “Glacial Shifts” by James Joshua OttoWatch this video on the NASA Goddard YouTube channel.Complete transcript available. MAVEN is the first spacecraft specifically designed to study the Mars upper atmosphere, in order to better understand the evolution of its climate. Now, scientists have analyzed several years of data from MAVEN’s NGIMS instrument and produced the first map of wind currents in the Martian thermosphere (a layer of the upper atmosphere). This map led to an unexpected and surprising discovery – disturbances in high-altitude wind currents on Mars are caused by terrain features such as mountains and valleys on the planet’s surface. For More InformationSee [NASA.gov](https://www.nasa.gov/press-release/goddard/2019/mars-wind-map) Related pages

By measuring windspeed and direction in the Mars upper atmosphere, MAVEN has discovered that high-altitude wind currents are being disturbed by terrain features far below. MAVEN is the first spacecraft specifically designed to study the Mars upper atmosphere, in order to better understand the evolution of its climate. Now, scientists have analyzed several years of data from MAVEN’s NGIMS instrument and produced the first map of wind currents in the Martian thermosphere (a layer of the upper atmosphere). This map led to an unexpected and surprising discovery – disturbances in high-altitude wind currents on Mars are caused by terrain features such as mountains and valleys on the planet’s surface. For More InformationSee [NASA.gov](https://www.nasa.gov/press-release/goddard/2019/mars-wind-map) Related pages

Aerobraking plan for MAVEN. (left) Current MAVEN orbit around Mars — 6200-km highest altitude, and an orbit period of ~4.5 hours. (center) Aerobraking process — MAVEN performs a series of “deep dip” orbits approaching to within ~125 km of Mars at lowest altitude, causing drag from the atmosphere slow down the spacecraft. Over roughly three-hundred and sixty orbits spanning about two months, this slowing reduces the spacecraft’s highest altitude to ~4500 km and its orbit period to ~3.5 hours. (right) Post-aerobraking orbit, with reduced altitude and shorter orbit period. Aerobraking plan for MAVEN. (left) Current MAVEN orbit around Mars — 6200-km highest altitude, and an orbit period of ~4.5 hours. (center) Aerobraking process — MAVEN performs a series of “deep dip” orbits approaching to within ~125 km of Mars at lowest altitude, causing drag from the atmosphere slow down the spacecraft. Over roughly three-hundred and sixty orbits spanning about two months, this slowing reduces the spacecraft’s highest altitude to ~4500 km and its orbit period to ~3.5 hours. (right) Post-aerobraking orbit, with reduced altitude and shorter orbit period. This version has no labels. In February 2019, MAVEN began an aerobraking campaign to tighten its orbit around Mars. When the campaign finishes in late April, MAVEN's furthest distance from the planet will be reduced by about 1,700 kilometers and its orbital period will be shortened by an hour. The aerobraking campaign will improve MAVEN's ability to relay data from rovers on the surface of Mars, while also continuing to carry out its science objectives by studying the Mars upper atmosphere and its interaction with the solar wind. For More InformationSee [NASA.gov](https://www.nasa.gov/mission_pages/maven/main/index.html) Related pages

Visualization depicting NASA's MAVEN satellite in an elliptical orbit around Mars. The horizon is scanned to determine atmospheric makeup. Blue sections of the atmosphere represent regions that have been scanned, and total coverage is achieved after roughly six orbits. This video is also available on our YouTube channel. Print resolution still image - MAVEN in orbit around Mars Print resolution still image - MAVEN studying the atmosphere of Mars Print resolution still image - MAVEN studying the atmosphere of Mars NASA’s Mars Atmosphere and Volatile Evolution mission, or MAVEN, is the first spacecraft specifically designed to study the Mars upper atmosphere. MAVEN’s goal is to understand how Mars lost its thick, early atmosphere to space, and how this in turn caused it to lose its once hospitable climate.MAVEN’s orbit gives it the most comprehensive view of the Martian atmosphere to date. Circling the red planet every 4.5 hours on an elliptical path, MAVEN passes close to the north and south poles at an inclination of 75 degrees. This allows MAVEN to gather a north-south swath of data with each pass. At the same time, Mars itself rotates eastward beneath MAVEN, giving the orbiter longitudinal coverage. The combination of MAVEN’s orbit and Mars’ daily rotation provides a complete picture of the Martian atmosphere every day.While previous Mars orbiters have peered down at the planet's surface, MAVEN is spending part of its time gazing at the stars, observing the Martian atmosphere through a series of stellar occultations. As Mars rolls beneath MAVEN, due to the spacecraft's own orbital motion, background stars rise and set behind the planet. Their light dims as it passes through the tenuous atmosphere, with specific gases absorbing specific wavelengths. MAVEN uses its Imaging Ultraviolet Spectrograph to break apart this light and see which wavelengths are absorbed, allowing it to determine atmospheric composition at varying altitudes. For More InformationSee [NASA.gov](http://www.nasa.gov/mission_pages/maven/main/index.html) Related pages

Principal Investigator Bruce Jakosky talks about MAVEN’s science observations at Mars.Watch this video on the NASAexplorer YouTube channel.For complete transcript, click here. MAVEN gazes at the setting stars during one of its stellar occultation campaigns. MAVEN's near-polar orbit gives it latitudinal coverage of the Martian atmosphere, while the planet's daily rotation provides longitudinal coverage. During its periodic "deep dip" campaigns, MAVEN lowers its closest approach to only 125 km above Mars, dipping into the upper atmosphere to measure it in situ. When water molecules are split apart in the Martian atmosphere, the resulting hydrogen atoms escape more easily from the planet than the heavier oxygen atoms. Before MAVEN entered its final science-mapping orbit, it observed carbon, oxygen, and hydrogen at varying altitudes above Mars. The heavier carbon and oxygen atoms cling tightly to Mars, while hydrogen atoms extend far above the planet. High above the thin Martian skies, NASA’s MAVEN spacecraft is carrying out a mission: determine how Mars lost its early atmosphere, and with it, its water. While previous Mars orbiters have peered down at the planet’s surface, MAVEN is spending part of its time gazing at the stars, looking for subtle changes in their color as they dip through the limb of Mars and set below the horizon. Such stellar occultations reveal what the atmosphere is made of, and how its composition varies with altitude. MAVEN’s observations are providing the most detailed picture of the Mars upper atmosphere to date, helping scientists understand how Mars turned from a warm and wet planet in its youth, into the forbidding desert that we see today. For More InformationSee [NASA.gov](http://www.nasa.gov/mission_pages/maven/main/index.html) Related pages

MAVEN observes a stellar occultation with its IUVS instrument. By splitting apart the light of setting stars, MAVEN can determine the composition of the Martian atmosphere. NASA's Mars Atmosphere and Volatile Evolution mission (MAVEN) is the first spacecraft specifically designed to study the upper atmosphere of Mars. MAVEN's goal is to determine how Mars lost its thick early atmosphere, and with it, its once hospitable climate.While previous Mars orbiters have peered down at the planet's surface, MAVEN is spending part of its time gazing at the stars, observing the Martian atmosphere through a series of stellar occultations. As Mars rolls beneath MAVEN, due to the spacecraft's own orbital motion, background stars rise and set behind the planet. Their light dims as it passes through the tenuous atmosphere, with specific gases absorbing specific wavelengths. MAVEN uses its Imaging Ultraviolet Spectrograph to break apart this light and see which wavelengths are absorbed, allowing it to determine atmospheric composition at varying altitudes. For More InformationSee [NASA.gov](http://www.nasa.gov/mission_pages/maven/main/index.html) Related pages