Earth's Magnetic Field - A Hazard For Lunar Astronauts?

April 16, 2007
Earth\'s Moon

For four days every month the Moon passes through the magnetic field of the Earth and parts of the lunar surface are charged with static electricity. Next week Dr Mike Hapgood of the Rutherford Appleton Laboratory will present a model at the Royal Astronomical Society National Astronomy Meeting in Preston, which suggests that this charging may increase after the year 2012 and become an important issue for future lunar explorers.

Once in every orbit around the Earth the Moon moves through the magnetic tail - the region on the nightside of the Earth where the magnetic field is drawn out into a million or more kilometre long tail pointing away from the Sun. In the middle of the tail there is a region full of energetic electrons and other charged particles (the plasmasheet).

When the Moon passes through the plasmasheet these electrons can collect on parts of the lunar surface and charge them with static electricity. Observations from NASA’s Lunar Prospector spacecraft during 1998 confirm the existence of this charging.

Dr Hapgood’s model suggests that the exposure of the Moon to plasmasheet charging varies markedly over an 18-year cycle linked to changes in the Moon's orbit. This exposure was low at the time of the Apollo landings in the early 1970s and is low again today - but it was high in the 1990s and will rise again after 2012. The United States, Russia, India, Japan and China have all announced plans to send astronauts back to the Moon around the year 2020 – at the time when lunar surface charging is predicted to be high.

Lunar surface charging may be an important issue for future lunar exploration because it increases the risk of electric discharges, which can interfere with and damage sensitive electronics. It may also affect the behaviour of lunar dust, which is a recognised hazard for lunar astronauts as it can easily enter spacesuits, living quarters and equipment.

Dr Hapgood comments, “Electrical charging is one of the less well-known natural hazards of spaceflight. It’s important to understand it how this affects the Moon so spacecraft designers can use scientific knowledge to protect future explorers.”

Source: Royal Astronomical Society

Explore further: Researcher crashes into moon mystery solution

Related Stories

Researcher crashes into moon mystery solution

October 12, 2017

Western researcher Philip Stooke may soon get his own television series – CSI: The Moon – if he keeps uncovering mysterious crash sites on the omnipresent astronomical body.

Returning humanity to the Moon

September 21, 2017

In the first act of lunar exploration, Neil Armstrong and Buzz Aldrin were major characters. In setting its sights on the moon, ESA hopes to bring many more actors to this off-world stage.

Solar eruptions could electrify Martian moons

October 18, 2017

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 ...

Unique NASA Science Lab Tackles 'Sticky' Issue of Lunar Dust

August 24, 2005

In the safety-conscious, science-driven business of aerospace research, where laboratories routinely are set up as "clean rooms," in which sterility is paramount, Dr. Mian Abbas' lab is something of an anomaly. The word "dust" ...

Recommended for you

Solar minimum surprisingly constant

November 17, 2017

Using more than a half-century of observations, Japanese astronomers have discovered that the microwaves coming from the sun at the minimums of the past five solar cycles have been the same each time, despite large differences ...

3 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

johnmatt
not rated yet Jul 08, 2008
interesting stuff. I was reading this article about how the magnetic field may be changing ( http://blackandwh...ic-field ) and I wonder if it will have any impact on the men on the moon.
nilbud
not rated yet Apr 19, 2009
We're due a pole flip, depending on how long that takes we could all being for a gamma ray tan.
nilbud
not rated yet Apr 19, 2009
"we could all be in" even

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.