I'd be inclined to go with number 1. If it were number 2, they wouldn't have bothered removing information from websites and commanded radio-silence from all respectable journalists. If it were number 3, they'd have a tough time actually keeping it secret for long.

Given the image a few months ago of the broken ice block in the frozen sea (if that's what it was), then we can probably expect that this instrument was capable of returning a very important result very quickly.

It has been said numerous times that it will take a long time for them to understand what the instrument is telling them. If that is true, they would have to be careful, otherwise "look what we have found!" would be replaced with "oh, wait..." and much embarassment.

Chris

There was a New Scientist article a week or so ago that said the instrument was working, but they were having some difficulty interpreting the data. This hasn't been attempted on another planet remember.

http://www.esa.int/esaCP/Pr_38_2005_p_EN.html

Mars Express radar collects first surface data

Thanks for the link sunspot.
Everybody, please keep whinning. A little bit more and then maybe an update of the MARSIS website might take place

The article http://www.esa.int/esaCP/Pr_38_2005_p_EN.html (thanks Sunspot), says:

“The bulk of our work has just started, as we now have to be sure to clearly identify and isolate the echoes coming from the subsurface. To do this, we have to carefully screen all data and make sure that signals which could be interpreted as coming from different underground layers are not actually produced by surface irregularities. This will keep us occupied for a few more weeks at least.”

Lots of good email addresses for the prinicpal people on the team there also.

Lets try and out mail the viagra merchants.

Our patience will pay us a big bill! This sound like that the science hypotesis is still working at least and hope that there will have a big surprise before this year.

Rodolfo

Mars Express Preparing to Look Underground

Mars Express Preparing to Look Underground
Summary - (Aug 5, 2005) The MARSIS radar instrument on board Mars Express is now extended and fully operational, and ESA scientists have begun using it to probe beneath the surface of Mars in search of water and ice. During this initial commissioning phase, operators have used the instrument to examine Mars' topography to compare its reading against previous readings of the Red Planet to make sure its calibrated correctly. Within a few weeks they'll start isolating areas where the radar is penetrating beneath the surface to start mapping out underground layers.

Wait for few weeks!!

Rodolfo

More detail in the latest Panetary Soc article. here.

Anyone notice they had a graphical profile of Marsis data as part of a graph about Sharad at the MRO conf yesterday...

ARHGHGHG

That should be on the ESA website!!!!!

Doug

Doug,
Perhaps there is a silver lining here, if it points to transatlantic collaboration. For example the excellent Mars surface calibration data taken by Marsis -according to the recent status report- could be used to shorten the calibration effort of Sharad and/or enhance the Sharad accuracy via the Marsis dataset which would eliminate any systematic errors.

Or is this too optimistic from either an organisational or instrument-technical perspective?

How long is a 'few weeks'? Let's see some radar waves.

Mike, it has been emphasized repeatedly that it's going to take a long time to interpret this data properly. It took TWO YEARS to analyze the Apollo 17 radar sounder data properly -- and that was a far simpler world. See http://sci.esa.int/science-e/www/object/in...fobjectid=37206 .

The first MARSIS team meeting is in a few days from now, so probably expect a public release after it

^ Yeah they tell us how excited they are but not say much about any real data.

Yeah I know, I'm grumpy.

Grumpy? Me too!
But the stats show that so far 10149 times this thread has been read, make that 10150 with this visit, with not much hard content to talk about, really. It all adds up to the tremendous interest in what Marsis might deliver. Myself included of course, and I have the gut feeling that indeed Marsis will deliver what we all are hoping for.

I'll try to do a daily google to catch any early breaking news which might leak out of the ESA fortress and report back here as soon as I find something.

Fingers crossed,

Peter

ESA has published insights into the MARSIS radar data analysis, dated Oct 6th:

http://sci.esa.int/science-e/www/object/in...fobjectid=37917

Interesting reading, and it confirms -if ever there was a need- earlier posts in this thread about the complexity of the MARSIS experiment and the effort it is going to take to produce some results from the raw data.

Peter

The abstracts from the 42nd Vernadsky-Brown Microsymposium are finally on line ( http://www.geokhi.ru/~planetology/contents.html ), and Augustin Chicarro's abstract ( http://www.geokhi.ru/~planetology/theses/chicarro1.pdf ) mentions the very first tentative science result from MARSIS: "...[P]reliminary results of the subsurface sounding radar (MARSIS) indicate strong echoes coming from the surface but lack of echoes under the young smooth Northern plains, which may indicate the presence of thick and homogeneous plains deposits."

So the lack of echos under the Northern Plains would mean that there are no large deposits of subsurface ice? Bummer. I suppose the smooth plains is a loess deposit instead of an anticipated aquifer?

As I understand it - these types of instruments can only detect a transition between layers.

i.e. you could have a iceberg sat on the surface, but it would only tell you about the change between the iceberb and the surface under it - not the actual material itself.

Doug

This becomes less and less exciting.

Hmm well that's kind of a letdown. Though we ARE extrapolating from the slightest bit of information here and it isn't totally incongruous with the epithermal neutron flux mapping data from odyssey. Theres lots more H in the southern hemisphere....

That graph shows that the Meridiani Planum and Gusev Crater (slight higher than MP) have a middle level of quantity of Hydrogen.

For subsurface probing, MARSIS must operate under 800 kilometres altitude from the Martian surface, while for ionospheric sounding MARSIS provides acceptable results from a distance of up to 2000 kilometres. The radar vertical depth resolution is 150 metres (in the free space), while echo profiles of the subsurface are acquired at a lateral spacing of about 5 to 9 km, depending on the spacecraft altitude.

The MARSIS radar is designed to operate around the pericentre of the orbit, when the spacecraft is closer to the planet’s surface. In each orbit available to MARSIS, the radar is switched on for 36 minutes around this pericentre point, dedicating the central 26 minutes to subsurface observations and the first and last five minutes of the slot to active ionosphere sounding.

Nighttime is the environmental condition favourable to subsurface sounding, as the ionospheric plasma frequency is lowest. The ionosphere is more energised during the daytime and disturbs the radio signals used for subsurface observations. Although even during the daytime, the MARSIS instrument can detect signals from the surface and subsurface after proper ionospheric corrections are made.

The above is an extract from ESA and it does not mention about the places to be examined by MARSIS.

Does the Mars Express only scans the subsurface of northern plains or any place?

Rodolfo

Cheerier news on the initial MARSIS results from an upcoming paper at the Fall 2005 AGU meeting ( http://www.agu.org/cgi-bin/SFgate/SFgate?&...t;P13C-02" ):

"The MARSIS radar has been performing nominally since turn-on. Echoes from the surface are typically strong, with signal-to-noise ratios in the range of 30-50 dB. Later returns from off-nadir topographic clutter are evident and easily modeled using MOLA topography data. Many late echoes are observed that cannot be explained as topographic clutter. These features are under investigation as potential subsurface interfaces."

So it's seeing SOMETHING under the surface, even if we don't yet know what it is. As for Rodolfo's question about which parts of Mars' surface will be scanned by MARSIS:

"As the periapsis of the Mars Express orbit migrates toward the south pole, the polar layered deposits and related landforms will be observed by MARSIS on the nightside. In addition, numerous targets of interest in the southern mid-latitudes will be acquired during the nightside, including the floors of Hellas and Argyre basins, and the regions of strong remnant crustal magnetization."

It always somehow seemed a little unbelieveable to me that a tiny transmitter putting out ~15W could actually have enough energy to bounce off the surface of a planet a few 100s of miles away and return useful and (apparently) detailed data on surface structure. Hmm. I guess it must be pretty radio quiet way up there.

Besides MARSIS on Mars Express, another experiment is under way searching for ice in Mars underground.
They are using the SRI International's 46-meter (150-foot) radio telescope working in tandem with the Mars Odyssey UHF radio system.

More details at : http://mars.jpl.nasa.gov/odyssey/spotlight/20051024.html

Rakhir

http://www.esa.int/esaCP/SEM30WTLWFE_index_0.html

This was just a article about how it works.

Once again no real news.





Yeah yeah I'm grumpy again.