A Constant Stream of Charged Particles Impinges on Mars Atmosphere

A constant stream of charged particles impinges on Mars at roughly one million miles per hour. This solar wind is capable of picking up ions from Mars’ upper atmosphere and stripping them away from the planet out into space. MAVEN has measured this escape rate under present conditions to be about 100 grams (or ¼ lb.) per second.

Unlike Earth, which has the protection of a large, global magnetic field, Mars is directly impacted by the solar wind, although its tenuous atmosphere (< 1% of Earth’s) prevents the solar wind from impacting the planet’s surface.

The complete article courtesy of NASA’s MAVEN Mission to Mars

MAVEN Returns First Ever Measurements of Solar Wind Erosion at Mars

Scientists have long suspected the solar wind of stripping the Martian atmosphere into space, a process that may have turned Mars from a blue world early in its history into the red planet that we see today. In 2014, NASA’s MAVEN orbiter arrived at Mars and began studying its upper atmosphere.

Now, MAVEN has returned the first-ever measurements of solar wind erosion at Mars, observing ions in the upper atmosphere as they pick up energy from the electric field of the solar wind and escape to space. 

(Video credit: NASA’s Goddard Space Flight Center)

NASA Goddard
NASA – National Aeronautics and Space Administration

Article courtesy of
NASA’s MAVEN Mission to Mars

 

Space weather satellite ICON on course for summer 2017 launch

NASA’s ICON mission, depicted in this artist’s concept, will study the ionosphere from a height of about 350 miles to understand how the combined effects of terrestrial weather and space weather influence this ionized layer of particles. (NASA image)

NASA’s ICON mission, depicted in this artist’s concept, will study the ionosphere from a height of about 350 miles to understand how the combined effects of terrestrial weather and space weather influence this ionized layer of particles. (NASA image)

NASA’s newest space weather research satellite, the Ionospheric Connection Explorer, is on course for a summer 2017 launch after UC Berkeley scientists and their colleagues shipped its four instruments to Utah for testing, prior to being packed into the final satellite.

The ICON mission, led by UC Berkeley’s Space Sciences Laboratory with the help of scientists and engineers from around the world, will add one more satellite to NASA’s fleet of 26 heliophysics satellites. Its mission: to understand the tug-of-war between Earth’s atmosphere and the space environment.

The complete article courtesy Robert Sanders, Media relations Berkeley News

 

MAVEN scientists analyze data to derive the history of Mars’ atmosphere:

(Image credit: NASA/GSFC)

(Image credit: NASA/GSFC)

MAVEN scientists analyze data from the spacecraft and take three approaches to derive the history of Mars’ atmosphere:
— Use ratios of stable isotopes to determine the integrated loss to space
— Use observed changes in escape in response to changing energetic inputs to directly extrapolate back in time
— Model escape processes using current conditions and extrapolate models back in time

Taking these approaches allows MAVEN scientists to determine how various space weather events affect the upper atmosphere of Mars today and how they have contributed to its evolution over time. Capturing events of different magnitudes becomes more likely over time and contributes to producing more accurate model extrapolations back in time.

MAVEN data enable scientists to:
— Investigate atmospheric escape response to regular solar wind variations and to major events (solar flares, coronal mass ejections)
— Update an estimate of solar wind evolution
— Determine how solar energetic particles contribute to escape, and
— Estimate integrated historical loss to space

In order to accurately model Mars’ atmospheric evolution, MAVEN scientists not only consider major solar events that occur today, but they also use data from the Kepler Mission to model the output of Sun-like stars at various points in their evolution.

One complicating factor is that the tilt of Mars’ spin axis (obliquity) has varied between 15° and 45° over just the past 10 million years and between 0° and 70° over billions of years.

Article and photos courtesy of NASA’s MAVEN Mission to Mars

'NASA scientists have determined that a primitive ocean on Mars held more water than Earth's Arctic Ocean and that the Red Planet has lost 87 percent of that water to space. Image Credit: @[54971236771:274:NASA - National Aeronautics and Space Administration]/ @[395013845897:274:NASA Goddard]'
'The sweep of NASA Kepler mission’s search for small, habitable planets is shown in this artist's concept. The first planet smaller than Earth, Kepler-20e, was discovered in December 2011 orbiting a Sun-like star slightly cooler and smaller than our sun every six days. But it is scorching hot and unable to maintain an atmosphere or a liquid water ocean. Kepler-22b was announced in the same month, as the first planet in the habitable zone of a sun-like star, but is more than twice the size of Earth and therefore unlikely to have a solid surface. Kepler-186f was discovered in April 2014 and is the first Earth-size planet found in the habitable zone of a small, cool M dwarf about half the size and mass of our sun. Kepler-452b is the first near-Earth-Size planet in the habitable zone of a star very similar to the sun. (Image credit: @[338122981393:274:NASA Ames Research Center]/W. Stenzel)'
'Changes in Tilt of Mars' Axis Modern-day Mars experiences cyclical changes in climate and, consequently, ice distribution. Unlike Earth, the obliquity (or tilt) of Mars changes substantially on timescales of hundreds of thousands to millions of years. At present day obliquity of about 25-degree tilt on Mars' rotational axis, ice is present in relatively modest quantities at the north and south poles (top left). This schematic shows that ice builds up near the equator at high obliquities (top right) and the poles grow larger at very low obliquities (bottom) (Image credit: @[8261258923:274:NASA Jet Propulsion Laboratory]-Caltech)'

Radiation Belt Processes in a Declining Solar Cycle

An artist’s rendering of the twin Van Allen Probes observatories with fully deployed instruments trailing each other along a geocentric orbit (an ellipse measuring 1.1 × 5.8 Earth radii), cutting through the inner magnetosphere. Over the extended mission, the probes will quantify the processes governing Earth’s radiation belt and ring current environment as the solar cycle transitions from solar maximum through the declining phase.

An artist’s rendering of the twin Van Allen Probes observatories with fully deployed instruments trailing each other along a geocentric orbit (an ellipse measuring 1.1 × 5.8 Earth radii), cutting through the inner magnetosphere. Over the extended mission, the probes will quantify the processes governing Earth’s radiation belt and ring current environment as the solar cycle transitions from solar maximum through the declining phase.

The Van Allen Probes began an extended mission in November to advance understanding of Earth’s radiation belts.

The morning of 30 August 2012 saw an Atlas 5 rocket launch of the twin Radiation Belt Storm Probes, the second spacecraft mission in NASA’s Living with a Star program. The probes settled into an elliptic orbit that cut through Earth’s radiation belts, home to highly variable populations of energetic particles dangerous to astronauts’ health and spacecraft operation. Renamed the Van Allen Probes soon after launch, the spacecraft are equipped with instruments designed to determine how these high-energy particles form, respond to solar variations, and evolve in space environments.

During their prime mission, the Van Allen Probes verified and quantified previously suggested energization processes, discovered new energization mechanisms, revealed the critical importance of dynamic plasma injections into the innermost magnetosphere, and used uniquely capable instruments to unveil inner radiation belt features that were all but invisible to previous sensors.

Now, through an extended mission that began 1 November 2015, the Van Allen Probes will advance understanding of the dynamics of near-Earth particle radiation. The overarching objective of this extended mission is to quantify the mechanisms governing Earth’s radiation belt and ring currentenvironment as the solar cycle transitions from solar maximum through the declining phase.

The complete article thanks to EOS magazine, here:

MAVEN Observes Mars Moon Phobos in the Mid- and Far-Ultraviolet

Phobos

(Image credits: University of Colorado Boulder/Laboratory for Atmospheric and Space Physics/NASA)

Due to a recent close encounter between MAVEN and Mars’ moon Phobos, scientists at NASA – National Aeronautics and Space Administration are closer to solving the mystery of how the moon formed.

In late November and early December 2015, the ‪#‎MAVEN‬ mission made a series of close approaches to the ‪#‎Martian‬ moon Phobos, collecting data from within 300 miles (500 km) of the moon.

Among the data returned were spectral images of ‪#‎Phobos‬ in the ultraviolet. The images will allow MAVEN scientists to better assess the composition of this enigmatic object, whose origin is unknown.

Read the full story, here:

12764516_10154114523917868_5182627020973910694_o

(Image credits: University of Colorado Boulder/Laboratory for Atmospheric and Space Physics/NASA)

 

Study finds surprising variability in shape of Van Allen Belts

1. The traditional idea of the radiation belts includes a larger, more dynamic outer belt and a smaller, more stable inner belt with an empty slot region separating the two. However, a new study based on data from NASA’s Van Allen Probes shows that all three regions—the inner belt, slot region, and outer belt—can appear differently depending on the energy of electrons considered and general conditions in the magnetosphere. 2. At the highest electron energies measured—above 1 MeV—researchers saw electrons in the outer belt only. 3. The radiation belts look much different at the lowest electron energy levels measured, about 0.1 MeV. Here, the inner belt is much larger than in the traditional picture, expanding into the region that has long been considered part of the empty slot region. The outer belt is diminished and doesn’t expand as far in these lower electron energies. 4. During geomagnetic storms, the empty region between the two belts can fill in completely with lower-energy electrons. Traditionally, scientists thought this slot region filled in only during the most extreme geomagnetic storms happening about once every ten years. However, new data shows it’s not uncommon for lower-energy electrons—up to 0.8 MeV—to fill this space during almost all geomagnetic storms. Credit: NASA Goddard/Duberstein

1. The traditional idea of the radiation belts includes a larger, more dynamic outer belt and a smaller, more stable inner belt with an empty slot region separating the two. However, a new study based on data from NASA’s Van Allen Probes shows that all three regions—the inner belt, slot region, and outer belt—can appear differently depending on the energy of electrons considered and general conditions in the magnetosphere. 2. At the highest electron energies measured—above 1 MeV—researchers saw electrons in the outer belt only. 3. The radiation belts look much different at the lowest electron energy levels measured, about 0.1 MeV. Here, the inner belt is much larger than in the traditional picture, expanding into the region that has long been considered part of the empty slot region. The outer belt is diminished and doesn’t expand as far in these lower electron energies. 4. During geomagnetic storms, the empty region between the two belts can fill in completely with lower-energy electrons. Traditionally, scientists thought this slot region filled in only during the most extreme geomagnetic storms happening about once every ten years. However, new data shows it’s not uncommon for lower-energy electrons—up to 0.8 MeV—to fill this space during almost all geomagnetic storms. Credit: NASA Goddard/Duberstein

Findings could impact how we protect technology in space

LOS ALAMOS, N.M., Feb. 23, 2016—The shape of the two electron swarms 600 miles to more than 25,000 miles from the Earth’s surface, known as the Van Allen Belts, could be quite different than has been believed for decades, according to a new studyof data from NASA’s Van Allen Probes that was released Friday in the Journal of Geophysical Research.

“The shape of the belts is actually quite different depending on what type of electron you’re looking at,” said Geoff Reeves of Los Alamos National Laboratory’s Intelligence and Space Research Division and lead author on the study. “Electrons at different energy levels are distributed differently in these regions.”

Read the complete article courtesy of Los Alamos National Laboratory

MAVEN Instruments Study the Solar Wind at Mars

The ‪#‎MAVEN‬ spacecraft is equipped with several instruments devoted to measuring the solar wind and how solar energetic particles and extreme ultraviolet irradiance interact with Mars’ upper atmosphere. These experiments have been specifically designed to determine whether space weather events increase atmospheric escape rates to historically important levels.

In analyzing data from these instruments, MAVEN scientists will take three approaches to derive the history of Mars’ atmosphere:

1. Use ratios of stable isotopes to determine the integrated loss to space
2. Use observed changes in escape in response to changing energetic inputs to directly extrapolate back in time
3. Model escape processes using current conditions and extrapolate models back in time

Taking these approaches enables our team scientists to determine how various space weather events affect the upper atmosphere of Mars today and how they have contributed to its evolution over time. Capturing events of different magnitudes becomes more likely over time and contributes to producing more accurate model extrapolations back in time.

MAVEN data is allowing scientists to:

  • Investigate atmospheric escape response to regular solar wind variations and to major events (solar flares, coronal mass ejections)
  • Update an estimate of solar wind evolution
  • Determine how solar energetic particles contribute to escape, and
  • Estimate integrated historical loss to space

NASA Goddard