Subscribe to our free daily newsletters
  Mars Exploration News  




Subscribe to our free daily newsletters



MARSDAILY
Solar eruptions could electrify Martian moons
by Staff Writers
Greenbelt MD (SPX) Oct 19, 2017


The study shows that this plasma void behind Phobos may create a situation where astronauts and rovers build up significant electric charges. For example, if astronauts were to walk across the night-side surface, friction could transfer charge from the dust and rock on the surface to their spacesuits. This dust and rock is a very poor conductor of electricity, so the charge can't flow back easily into the surface - and charge starts to build up on the spacesuits. On the day side, the electrically conducting solar wind and solar ultraviolet radiation can remove the excess charge on the suit.

Powerful solar eruptions could electrically charge areas of the Martian moon Phobos to hundreds of volts, presenting a complex electrical environment that could possibly affect sensitive electronics carried by future robotic explorers, according to a new NASA study. The study also considered electrical charges that could develop as astronauts transit the surface on potential human missions to Phobos.

Phobos has been considered as a possible initial base for human exploration of Mars because its weak gravity makes it easier to land spacecraft, astronauts and supplies. The idea would be to have the astronauts control robots on the Martian surface from the moons of Mars, without the considerable time delay faced by Earth-based operators.

"We found that astronauts or rovers could accumulate significant electric charges when traversing the night side of Phobos - the side facing Mars during the Martian day," said William Farrell of NASA's Goddard Space Flight Center, Greenbelt, Maryland.

"While we don't expect these charges to be large enough to injure an astronaut, they are potentially large enough to affect sensitive equipment, so we would need to design spacesuits and equipment that minimizes any charging hazard." Farrell is lead author of a paper on this research published online Oct. 3 in Advances in Space Research.

Mars has two small moons, Phobos and Deimos. Although this study focused on Phobos, similar conditions are expected at Deimos, since both moons have no atmosphere and are directly exposed to the solar wind - a stream of electrically conducting gas, called a plasma, that's constantly blowing off the surface of the Sun into space at around a million miles per hour.

The solar wind is responsible for these charging effects. When the solar wind strikes the day side of Phobos, the plasma is absorbed by the surface. This creates a void on the night side of Phobos that the plasma flow is obstructed from directly entering. However, the composition of the wind - made of two types of electrically charged particles, namely ions and electrons - affects the flow.

The electrons are over a thousand times lighter than the ions. "The electrons act like fighter jets - they are able to turn quickly around an obstacle - and the ions are like big, heavy bombers - they change direction slowly," said Farrell. "This means the light electrons push in ahead of the heavy ions and the resulting electric field forces the ions into the plasma void behind Phobos, according to our models."

The study shows that this plasma void behind Phobos may create a situation where astronauts and rovers build up significant electric charges. For example, if astronauts were to walk across the night-side surface, friction could transfer charge from the dust and rock on the surface to their spacesuits. This dust and rock is a very poor conductor of electricity, so the charge can't flow back easily into the surface - and charge starts to build up on the spacesuits. On the day side, the electrically conducting solar wind and solar ultraviolet radiation can remove the excess charge on the suit.

But, on the night side, the ion and electron densities in the trailing plasma void are so low they cannot compensate or 'dissipate' the charge build-up. The team's calculations revealed that this static charge can reach ten thousand volts in some materials, like the Teflon suits used in the Apollo lunar missions. If the astronaut then touches something conductive, like a piece of equipment, this could release the charge, possibly similar to the discharge you get when you shuffle across a carpet and touch a metal door handle.

The team modeled the flow of the solar wind around Phobos and calculated the buildup of charge on the night side, as well as in obstructed regions in shadow, like Stickney crater, the largest crater on Phobos. "We found that excess charge builds up in these regions during all solar wind conditions, but the charging effect was especially severe in the wake of solar eruptions like coronal mass ejections, which are dense, fast gusts of solar wind," said Farrell.

This study was a follow-up to earlier studies that revealed the charging effects of solar wind in shadowed craters on Earth's Moon and near-Earth asteroids. Some conditions on Phobos are different than those in the earlier studies. For example, Phobos gets immersed in the plasma flowing behind Mars because it orbits Mars much closer than the Moon orbits Earth. The plasma flow behind Mars' orbit was modeled as well.

MARSDAILY
Russian Space Research Institute Announces July 2020 Date for Mission to Mars
Moscow (Sputnik) Oct 10, 2017
According to the head of the Russian Academy of Sciences' Space Research Institute, the launch of the ExoMars-2020 mission, which will send a European rover to the red planet, is scheduled for July 24, 2020. The launch of the ExoMars-2020 mission from the Baikonur Cosmodrome in Kazakhstan is tentatively scheduled for July 24, 2020, head of the Russian Academy of Sciences' Space Research In ... read more

Related Links
Goddard Space Flight Center
Mars News and Information at MarsDaily.com
Lunar Dreams and more


Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once


credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly


paypal only

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

MARSDAILY
Ancient asteroid impact exposes the moon's interior

How bright is the moon, really?

Moon Once Had an Atmosphere

Chinese moon missions delayed by rocket failure: report

MARSDAILY
China launches three satellites

Mars probe to carry 13 types of payload on 2020 mission

UN official commends China's role in space cooperation

China's cargo spacecraft separates from Tiangong-2 space lab

MARSDAILY
Earth's New Traveling Buddy Is an Asteroid, Not Space Junk

Number of Undiscovered Near-Earth Asteroids Revised Downward

Asteroid Tracking Network Observes Close Approach

Close Approach of Asteroid 2012 TC4 Poses no Danger to Earth

MARSDAILY
Haumea, the most peculiar of Pluto companions, has a ring around it

Ring around a dwarf planet detected

Helicopter test for Jupiter icy moons radar

Solving the Mystery of Pluto's Giant Blades of Ice

MARSDAILY
Reconstructing Cassini's Plunge into Saturn

Saturn's A ring contained by not one, but seven moons

Intense storms batter Saturn's largest moon, UCLA scientists report

NASA's $3.9 bn Cassini spacecraft makes death plunge into Saturn

MARSDAILY
Air quality-monitoring satellite in orbit

Watching plant photosynthesis from space

Russia launches European satellite to monitor Earth's atmosphere

Baltic clams and worms release as much greenhouse gas as 20,000 dairy cows

MARSDAILY
Russia launches cargo ship to space station

Roscosmos: International Space Exploration to Continue Despite Geopolitical Situation

US spacewalkers install 'new eyes' at space station

NASA May Extend BEAM's Time on the International Space Station

MARSDAILY
Astronomers find potential solution into how planets form

A star that devoured its own planets

Giant Exoplanet Hunters: Look for Debris Disks

Are Self-Replicating Starships Practical




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News






The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement