Mars Express latest findings give hints about water loss in the Martian atmosphere

Sep 27, 2004
Mars Express latest findings give hints about water loss in the Martian atmosphere

Recent results from the ASPERA-3 instrument on board Mars Express confirm that a very efficient process is at work in the Martian atmosphere which could explain the loss of water. Water is believed to have once been abundant on the Red Planet. Professor Rickard Lundin, leader of the ASPERA-3 team, describes these findings in a paper published in the latest issue of Science.

Mars is bombarded by a flood of charged particles from the Sun, commonly called the ‘solar wind’ and consisting of electrons and alpha particles. The solar wind erodes the atmosphere of Mars, and is believed to have stripped away a large amount of water that was present on the planet about 3.8 billion years ago. Geological evidence, as recently confirmed by images from the High Resolution Stereo Camera (HRSC) onboard Mars Express, indicates that water flows and even an ocean in the Northern hemisphere shaped the surface of Mars.

Today, water still exists on the Red Planet, but less than in the past. Observations made earlier this year by the OMEGA instrument on Mars Express showed that Mars has vast fields of perennial water ice, stretching out from its south pole.

The ASPERA-3 instrument on board Mars Express aims to answer the question of whether the solar wind interaction with the upper atmosphere of Mars contributes to the depletion of water. It is measuring a process called ‘solar wind scavenging’, or the slow ‘invisible’ escape of volatile gases and liquid compounds which make up the atmosphere and hydrosphere of a planet. Using plasma spectrometers and a special imager to detect energetic neutral atoms, ASPERA-3 is making global and simultaneous measurements of the solar wind, the inflow of energetic particles, and also the ‘planetary wind’, which is the outflow of particles from the Martian atmosphere and ionosphere.

Aspera 3 has established that the solar wind penetrates through the ionosphere and very deeply into the Martian atmosphere down to an altitude of 270 kilometres. This seems to be the reason for the acceleration processes that cause the loss of atmosphere on Mars.

Source: ESA

Explore further: Planck: Gravitational waves remain elusive

add to favorites email to friend print save as pdf

Related Stories

Gully patterns document Martian climate cycles

Jan 28, 2015

Geologists from Brown University have found new evidence that glacier-like ice deposits advanced and retreated multiple times in the midlatitude regions of Mars in the relatively recent past.

Getting to know Rosetta's comet

Jan 23, 2015

Rosetta is revealing its host comet as having a remarkable array of surface features and with many processes contributing to its activity, painting a complex picture of its evolution.

Gullies on Vesta suggest past water-mobilized flows

Jan 23, 2015

(Phys.org)—Protoplanet Vesta, visited by NASA's Dawn spacecraft from 2011 to 2013, was once thought to be completely dry, incapable of retaining water because of the low temperatures and pressures at its ...

Some of the best pictures of the planets in our solar system

Jan 19, 2015

Our Solar System is a pretty picturesque place. Between the Sun, the Moon, and the Inner and Outer Solar System, there is no shortage of wondrous things to behold. But arguably, it is the eight planets that make up our Solar ...

Recommended for you

Planck: Gravitational waves remain elusive

14 hours ago

Despite earlier reports of a possible detection, a joint analysis of data from ESA's Planck satellite and the ground-based BICEP2 and Keck Array experiments has found no conclusive evidence of primordial ...

Going a long way to do a quick data collection

20 hours ago

Like many a scientist before me, I have spent this week trying to grow a crystal. I wasn't fussy, it didn't have to be a single crystal – a smush of something would have done – just as long as it had ...

How are planets formed?

20 hours ago

How did the Solar System's planets come to be? The leading theory is something known as the "protoplanet hypothesis", which essentially says that very small objects stuck to each other and grew bigger and ...

What's happening in the universe right now?

21 hours ago

There are some topics that get a little frustrating in their pedantry, but can really draw attention to the grand scope and mechanics in our Universe. This is definitely one of them.

User comments : 0

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.