Mars Wind Currents Reveal a Surprising Feature

MAVEN data have enabled the first map of the electric current systems (blue and red arrows) that shape the induced magnetic field surrounding Mars.Credit: NASA/Goddard/MAVEN/CU Boulder/SVSUniversal Production Music: “A Lucid Dream” and “Shimmer Oscillations” by James Joshua OttoWatch this video on the NASA Goddard YouTube channel.Complete transcript available. || Five years after NASA’s MAVEN spacecraft entered into orbit around Mars, data from the mission has led to the creation of a map of electric current systems in the Martian atmosphere. Unlike Earth, Mars lacks a protective global magnetic field to shield its upper atmosphere from the solar wind. Instead, the solar wind crashes into the upper atmosphere and its magnetic field lines drape around the planet. This creates an induced magnetosphere that tugs on charged particles in the Mars upper atmosphere, generating electric currents. Now, MAVEN’s detailed measurements of the magnetic environment surrounding Mars have revealed the shape of these electric currents for the first time.Read the science paper in Nature Astronomy. || In this data visualization, the yellow arrow at upper left shows the direction of the solar wind at Mars, while cyan lines depict the solar wind magnetic field observed by MAVEN. Blue and red arrows indicate the direction of electric currents in the Mars upper atmosphere, which were derived from several years of MAVEN data. These currents provide structure for the magnetic environment surrounding Mars, including the solar wind bow shock (gray outer paraboloid) and the Mars induced magnetosphere (green inner paraboloid).Credit: NASA/Goddard/MAVEN/CU Boulder/SVS

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. || In February 2019, MAVEN began an aerobraking campaign to tighten its orbit around Mars. When the campaign finishes in late April, 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. || 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.

MAVEN Deep Dip Animation || NASA s orbit is lowered to only 125 km at closest approach, dipping into the upper atmosphere to study it in situ.This animation depicts MAVEN maneuvering from its normal science orbit to the deep dip orbit and back. The animation is available for download in broadcast-quality HD and can be looped. || MAVEN Deep Dip Textless