Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Mars Express radar data analysis is on the move


The Mars Express radar, MARSIS, has now been deployed for more than four months. Here we report on the activities so far.

For the operational period up to now, Mars Express has been making its closest approaches to Mars predominantly in the daytime portion of its orbit. The MARSIS radar’s scientists are mainly collecting data about the upper layers of the Martian atmosphere, or ‘ionosphere’, which is the highly electrically conducting layer that is maintained by sunlight.

They are also continuing the laborious analysis of all data gathered during the first night-time observations last summer, especially in the search for and interpretation of possible signals from subsurface layers. This includes the search for a possible signature of underground water, in frozen or liquid state.

Radar science is a complex business - it is based on the detection of radio waves reflected by boundaries between different materials. By analysis of these ‘echoes’, it is possible to deduce information about the kind of material causing the reflection, such as estimates of its composition and physical state.

Different materials are characterised by their ‘dielectric constant’, that is the specific way they interact with electromagnetic radiation, such as radio waves. When a radio wave crosses the boundary of different layers of ‘material’, an echo is generated and carries a sort of ‘fingerprint’ from the specific materials.

From the time delay for an echo to be received by the radar instrument, the distance or the depth of the layers of material producing the echo can be deduced.

While the Mars Express point closest approach is in daylight, MARSIS is only operating at higher frequencies within its capability because the lower-frequency radio signals get disturbed. With these higher frequencies, MARSIS can study the ionosphere and the surface, while some shallow subsurface sounding can still be attempted.

During night-time observations, like those performed briefly last summer immediately after deployment, it is possible for MARSIS to use all frequencies for scientific measurements, including the lowest ones, suitable for penetrating under the soil of Mars.

Tuning to different frequencies for different targets in different conditions is not the only secret of MARSIS. The instrument, responding to signals reflected from any direction, requires scientists also do a huge amount of analysis work to remove these interfering signals from the echoes.

A typical example of what they look for is ‘clutter backscattering’, which are reflections apparently coming from the subsurface, but actually produced by irregularities in the surface terrain that delay the return of the echo. For this ‘cleaning’ work, the team also makes use of ‘surface echo simulator’ computer programs.

In the first months of operations, MARSIS performed its first ionospheric sounding. The data are converted into typical plots, called ‘ionograms’, where the altitude at which the echo was generated, deduced by the echo time delay, is given for each transmitted frequency. The intensity of the various echo signals detected is indicated in different colours.

In parallel to the analysis of surface and subsurface signals, the scientists are studying all ionograms to draw the first conclusions on the nature and behaviour of the ionosphere of Mars, and of its interaction with the planet and the surrounding environment.

Agustin Chicarro | alfa
Further information:

More articles from Physics and Astronomy:

nachricht Move over, lasers: Scientists can now create holograms from neutrons, too
21.10.2016 | National Institute of Standards and Technology (NIST)

nachricht Finding the lightest superdeformed triaxial atomic nucleus
20.10.2016 | The Henryk Niewodniczanski Institute of Nuclear Physics Polish Academy of Sciences

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>