Released Results

IUVS observations of a proton aurora
MAVEN observations of a proton aurora. In the top panel, natural variability of the solar wind results in occasional dense flows of solar wind protons bombarding Mars. At bottom, observations by MAVEN’s Imaging Ultraviolet Spectrograph show increased ultraviolet emission from the atmosphere when the solar wind is enhanced.

The Martian atmosphere during a proton aurora
This animation shows a proton aurora at Mars. First, a solar wind proton approaches Mars at high speed and encounters a cloud of hydrogen surrounding the planet. The proton steals an electron from a Martian hydrogen atom, thereby becoming a neutral atom. (more)

Solar Storm Triggers Whole-Planet Aurora at Mars
These images from the MAVEN Imaging Ultraviolet Spectrograph show the appearance of a bright aurora on Mars during a solar storm in September 2017. The purple-white colors shows the intensity of ultraviolet light on Mars' night side before and during the event. (more)

Sun Storm Triggers Whole-Planet Aurora at Mars (Video)
This animation shows the sudden appearance of a bright aurora on Mars during a solar storm. The purple-white color scheme shows the intensity of ultraviolet light over the course of the event, from observations on Sept. 12 and 13, 2017, by the MAVEN Imaging Ultraviolet Spectrograph. (more)

Martian Aurora 25 Times Brighter Than Prior Brightest
These profiles show the brightness of auroras in Mars’ atmosphere at different altitudes. The solid black profile on the right is from a September 2017 solar storm. Barely visible along the vertical axis is a dashed profile from the previous brightest aurora seen by MAVEN, in March 2015.(more)

Solar Storm's Radiation at Martian Orbit and Surface
Energetic particles from a large solar storm in September 2017 were seen both in Mars orbit by NASA's MAVEN orbiter, and on the surface of Mars by NASA's Curiosity Mars rover.(more)

IUVS reveals cloud formation on Mars
Images from MAVEN's Imaging UltraViolet Spectrograph show rapid cloud formation on Mars on July 9-10, 2016. Time progresses from upper left to lower right with 2.2 hours spacing. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. Mars' day is similar to Earth’s, so the images show just over a quarter day. (more)

Ultraviolet image of Mars' south pole during southern spring
This ultraviolet image near Mars’ South Pole was taken on July 10, 2016 and shows the atmosphere and surface during southern spring. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. Darker regions show the planet's rocky surface and brighter regions are due to clouds, dust and haze. (more)

Mars nightside ultraviolet emission from nitric oxide
This image of the Mars nightside shows ultraviolet emission from nitric oxide (abbreviated NO). The emission is shown in false color with black as low values, green as medium, and white as high. These are the first such images obtained at Mars. Nightglow is a common planetary phenomenon in which the sky faintly glows even in the complete absence of external light. (more)

IUVS captures sharpened ultraviolet view of Mars
MAVEN's Imaging UltraViolet Spectrograph obtained this image of Mars on July 13, 2016, when the planet appeared nearly full as viewed from the highest altitudes in the MAVEN orbit. The ultraviolet colors of the planet have been rendered in false color, to show what we would see with ultraviolet-sensitive eyes. (more)

Phobos as observed by MAVEN IUVS
Orange shows mid-ultraviolet (MUV) sunlight reflected from the surface of Phobos, exposing the moon's irregular shape and many craters. Blue shows far ultraviolet light detected at 121.6 nm, which is scattered off of hydrogen gas in the extended upper atmosphere of Mars. Phobos, observed here at a range of 300km, blocks this light, eclipsing the ultraviolet sky. (more)

The solar wind at Mars and Earth
In this artist’s concept, the solar wind interacts with Mars’ upper atmosphere, but is deflected past Earth by a global magnetic field. (Courtesy NASA/GSFC)

Observed average solar wind flow at Mars
Average solar wind flow at Mars as observed by the MAVEN spacecraft. The red color corresponds with higher observed solar wind densities. (Courtesy NASA/GSFC)

Mars in the path of a solar storm
A solar storm approaches Mars in this artist's concept. The Red Planet is thought to have lost much of its atmosphere to such extreme space weather. (Courtesy NASA/GSFC)

Mars solar storm ion loss
An artist’s rendition depicts a solar storm hitting Mars and stripping ions from the upper atmosphere. (Courtesy NASA GSFC)

Observed O+ ion flux chart
O+ ion flux chart as observed by the MAVEN spacecraft, showing tailward escape, which accounts for about 75% of the flux, and escape from the polar plume. (Courtesy NASA/GSFC)

Computer simulation of Mars' polar plume
Computer simulation of the interaction of the solar wind with electrically charged particles (ions) in Mars' upper atmosphere. The lines represent the paths of individual ions and the colors represent their energy, and show that the polar plume (red) contains the most-energetic ions. (Courtesy X. Fang, University of Colorado, and the MAVEN science team)

IUVS Observes the "Christmas lights aurora" on Mars
Shown here is an artist’s conception of MAVEN’s Imaging UltraViolet Spectrograph (IUVS) observing the “Christmas Lights Aurora" on Mars. MAVEN observations show that aurora on Mars is similar to Earth’s "Northern Lights" but has a different origin.
(Courtesy CU/LASP)

IUVS Map of Ultraviolet Aurora on Mars
Shown here is a map of the MAVEN IUVS auroral detections in December 2014 overlaid on Mars’ surface. The map shows that the aurora was widespread in the northern hemisphere, not tied to any geographic location. The aurora was detected in all observations during a 5-day period, though no data were taken in the southern hemisphere and some regions in the northern hemisphere were missed.
(Courtesy CU/LASP)

LPW Observes Dust in Mars Upper Atmosphere
This illustration—with the sun to the right—shows where the MAVEN Langmuir Probe and Waves (LPW) instrument observes low altitude dust in Mars' upper atmosphere. The blue circle marks the altitude of 300 km.
(Courtesy CU/LASP)

MAVEN Spacecraft Carrying Out Science Operations at Mars
This artist's conception shows the MAVEN spacecraft carrying out science operations at Mars. MAVEN has been in science mode since mid-November 2014.
(Courtesy NASA/GSFC)

The Solar Wind and its Interaction with Mars’ Ionosphere
Illustration (not to scale) showing the ability of the upstream bow shock and the magnetic field induced in the ionosphere to push the solar wind around the planet. As a result, the solar wind should not hit the ionosphere directly or penetrate deeply into the upper atmosphere. MAVEN's orbit early in the mission is shown schematically.
(Courtesy NASA/GSFC)

MAVEN SWIA Ion Measurements
SWIA measurements of the solar wind. At the highest altitudes (2,880 – 5,640 km), you can see the peaks at the correct energy/charge ratio for H+ and He++ in the free upstream solar wind. At intermediate altitudes (250 – 380 km), these peaks are not present, suggesting that the solar wind has not penetrated to these altitudes. However, the H+ peak shows up again at lower altitudes. (more)

Deep Penetration of Neutralized Solar Wind Ions
The proposed explanation for these SWIA observations is that the charged solar wind ions are neutralized by "charge exchange" reactions in the ionosphere. As neutrals, they are not pushed around the planet but can penetrate deeply. At lower altitudes, these same charge-exchange reactions can turn them back into ions, still traveling at the same speed as the initial solar-wind ions. (more)

Mars Atmospheric Reservoirs
This schematic demonstrates the relationship between solar-energy input, the composition of Mars’ upper atmosphere, and the composition of the lower atmosphere. This leads into the discussion of NGIMS results on the subsequent charts. NGIMS is able to measure the abundances of neutral and ionized atoms and molecules in the upper atmosphere.
(Courtesy NASA/GSFC)

MAVEN NGIMS Mass Spectrum
Mass spectrum obtained by NGIMS showing the different neutral and ionized species in the upper atmosphere and ionosphere. Although the composition at these altitudes has been measured twice, by the Viking lander entry vehicles, MAVEN represents the first comprehensive measurements at these altitudes.
(Courtesy Paul Mahaffy/GSFC)

NGIMS Measurements of Neutrals During One Orbit
Detailed measurements of neutrals during one pass of the MAVEN spacecraft through low altitudes (down to about 170 km). The data show that the ratio of species to each other changes with altitude, and also show that there is significant structure that is likely due to dynamical phenomena such as waves and upper-atmospheric weather.
(Courtesy Paul Mahaffy/GSFC)

NGIMS Measurements of Ions During One Orbit
Detailed measurements of ions during one pass of the MAVEN spacecraft through low altitudes (down to about 170 km). The data show that the ratio of species to each other changes with altitude, and also show that there is significant structure that is likely due to dynamical phenomena such as waves and upper-atmospheric weather.
(Courtesy Paul Mahaffy/GSFC)

STATIC Instrument on the MAVEN Spacecraft
This graphic shows the STATIC instrument on the MAVEN spacecraft. STATIC is able to measure the composition and velocity of ions, allowing us to determine escape rates at the present epoch.
(Courtesy NASA/GSFC/UCB-SSL)

Sample Spectra from MAVEN STATIC Instrument
A sample spectra from the MAVEN STATIC instrument, showing the ions that it can measure.
(Courtesy Jim McFadden/UCB-SSL)

STATIC Measurements of Composition and Energy of Ions
This series shows the composition and energy of ions as the MAVEN spacecraft moved from low (~250 km) to higher (~500 km) altitudes. At the higher altitudes, the ions have been accelerated, as indicated by their higher energy. We are seeing the acceleration from low-energy to higher energy as the ions are driven to escape speeds.
(Courtesy Jim McFadden/UCB-SSL)

STATIC Measures Escaping Polar Plume of Ions
This schematic illustration depicts the acceleration of ions from low-energy to higher energy, which leads to an escaping polar plume of ions.
(Courtesy NASA/GSFC)

Ions of Eight Metals from Comet Dust Detected in Mars Atmosphere
Data from NGIMS identified metal ions added to Mars' atmosphere shortly after comet Siding Spring sped close to Mars. NGIMS directly samples the composition of Mars’ upper atmosphere when the spacecraft dips into the top of the atmosphere during each orbit. These graphs show count rates of specific types of metal ions from each of multiple dips between Oct. 18 & Oct. 23, 2014. (more)

Comet Put Magnesium and Iron into Martian Atmosphere
This graph shows detection of metals added to the Martian atmosphere from dust particles released by a passing comet. The data are from the IUVS, which recorded the intensities of emission by ingredients in the Martian atmosphere just before (blue line) and after (red line) comet C/2013 A1 Siding Spring sped within about 87,000 mi (139,500 km) of Mars on Oct. 19, 2014. (more)

Ultraviolet Image of Comet Siding Spring’s Hydrogen Coma
The MAVEN spacecraft obtained an ultraviolet image of hydrogen surrounding comet Siding Spring on Friday, October 17th, two days before the comet’s closest approach to Mars. The IUVS instrument imaged the comet at a distance of 5.3 million mi (8.5 million km). The image shows sunlight that has been scattered by atomic hydrogen, and is shown as blue in this false-color representation. (more)

IUVS observation of atomic hydrogen
Atomic hydrogen scattering ultraviolet sunlight in the upper atmosphere of Mars, imaged by the MAVEN IUVS. Hydrogen is produced by the breakdown of water, which was once abundant on Mars’ surface. Hydrogen is light and weakly bound by gravity, so it extends far from the planet (indicated with a red circle) and can readily escape. (more)

IUVS observation of atomic carbon
Atomic carbon scattering ultraviolet sunlight in the upper atmosphere of Mars, imaged by the MAVEN IUVS. Carbon is produced by the breakdown of carbon dioxide, a potent greenhouse gas thought to be abundant in Mars’ past. Mars is indicated with a red circle; sunlight is illuminating the planet from the right. (more)

IUVS observation of atomic oxygen
Atomic oxygen scattering ultraviolet sunlight in the upper atmosphere of Mars, imaged by the MAVEN IUVS. Atomic oxygen is produced by the breakdown of carbon dioxide and water. Most oxygen is trapped near the planet, (indicated with a red circle) but some extends high above the planet and shows that that Mars is losing the gas to space. (more)

IUVS observation of Mars' ozone column
The geographical distribution of ozone in the southern hemisphere of Mars, imaged by the MAVEN IUVS. On Mars, ozone is primarily destroyed by the combined action of water vapor and sunlight. The cold, dark conditions near the pole allow ozone to accumulate there. (more)

First SEP event observations
This image shows the sequence of events leading up to the first SEP event observed by MAVEN at Mars. The top panel shows the distance between MAVEN and Mars as a function of time. The bottom panel shows Energetic Ion Flux as a function of particle energy (vertical axis) and time (horizontal axis). (more)

ENLIL model of Sept. 26, 2014 CME
This animation shows the evolution of the Sept. 26, 2014, coronal mass ejection shock front as it propagates toward Mars as generated by the WSA-Cone-ENLIL model simulations performed at the NASA Community Coordinated Modeling Center. The color map represents the density of the solar wind plasma in the inner heliosphere from near the sun out to twice the distance of Earth's orbit. (Courtesy NASA/GSFC)

IUVS first light
The MAVEN IUVS instrument obtained these false-color images eight hours after the successful completion of Mars orbit insertion by the MAVEN spacecraft at 10:24 p.m. EDT Sunday, Sept. 21. The image shows the planet from an altitude of 36,500 km in three ultraviolet wavelength bands. (more)