New Mars Express And Huygens Results, ESA conference - November 30, 2005 Options

[RNeuhaus]

Well, keep in mind that the central goal of Martian exploration is still finding promising possible fossil beds.

Only fossil? but also for the actual habits or not? Under the appropiate sub-surface where any lichen might be waiting for our visit...

Rodolfo

[Guest_AlexBlackwell_*]

Not necessarily. Even here on Earth some ice-caps are "cold-based", i e frozen to the substratum (the central part of the Scandinavian ice-cap during the last glaciation for example). If there is basal melting on Mars I would expect this to be a cyclic phenomenon. The existence of the layered terrain near the pole is a pretty strong proof of climatic cyclicity by itself.

The "cyclical, cold-based" model you outline above is certainly plausible, especially given that orbital forcing undoubtedly plays a critical role in Mars' ice ages; however, given that Mars' current obliquity is about intermediate in the cycle, I would presume the current basal load would support detectable melt.

The best evidence would be the morphology of the surface under the ice-cap. Wet-based ice moves over the substrate and has great erosive power while cold-based ice hardly erodes the substrate at all.
However I'm not sure whether MARSIS has sufficient definition to see e. g. drumlins or tunnel valleys beneath the ice.

It's early days but I, too, suspect that MARSIS, even with longer integration period and repeat coverage over the northern polar cap, may lack the ability to resolve any remnant structure indicating a basal melt flow towards the equatorial regions.

This post has been edited by AlexBlackwell: Dec 8 2005, 05:13 PM

[JonClarke]

Since the ESA -- to my amazement -- seems to be serious about flying ExoMars (maybe serious enough to cancel BepiColombo for it), the obvious question is: should both it AND MSL be sent to phyllosilicate sites, or should one of them be sent to a different type of terrain, such as a Meridiani-type sulfate deposit?  (A pretty strong case can be made, actually, that they SHOULD both go to diferent phyllosilicate sites.)

I don't think there can be any dount that ExoMars has been a very serious and strong contender of a future Mars mission for quite some time. So it is good that it looks like full funding has now been confirmed through 2011.

The phillosilicate sites are as follows:

1. Isemenius Lacus – slightly rougher at MOC scale than the MER sites, rare mesas, fairly featureless 34.0 N

2. Syrtis Major site – somewhat rougher at all scales compared to equivalent imagery of MER sites, lots of rampart craters, diversity of surface geological units, channel-like feature, 19.91 degrees N

3. Mwarth Vallis site – much rougher at all scales compared to equivalent imagery of MER sites, diversity of surface geological units, distinct channel-like feature, 24.54 N

4. Nili Fossae site – very much rougher at all scales compared to equivalent imagery of MER sites, diversity of surface geological units, rift-like features, mesas, dunes, possible fans 24.54 N

As you would expect, the more interesting the site the rougher the topography. I would suggest that site 2 is a good compromise although i would like 3 or 4. A lot depends on the nature of the landing system as to how rough a site it can land in, both in respect to small scale surface roughness and hazard avoidance. All of these sites are within the 45 degrees N or S of the equator limits specified by ExoMars.

Opportunity went to Merdiani in search of haematite and found sulphate as the big item. ExoMars will go to Syrtis (or wherever) and will find ?????

Jon

[JonClarke]

So that's the deal, then?  I was reading the Bepi cancellation as evidence that ESA science was going to be slowly strangled....

ExoMars is funded out of the Aurora, not the science budget. As I understand, science funding is based on per capita ESA-wide contributions wheras Aurora projects by project-specific funding from individual nations.

Two recent BBC stories:

http://news.bbc.co.uk/2/hi/science/nature/4503680.stm

http://news.bbc.co.uk/2/hi/science/nature/4507122.stm

Jon

[RNeuhaus]

The above 4 mentioned sites of interest for ExoMars since they have high probability to find phillosilicate. All of those terrain are rough, covered with stones like the Viking 1 and 2 sites. On the other hand, David Parker, David Parker, director of space science at the British National Space Centre, said the mission would build on the heritage of Beagle 2.

"Imagine a spacecraft landing on Mars using parachutes and airbags, maybe a rocket system of some sort," he told the BBC News website.

Hope it won't be a repeated mistake. No airbag on these rough sites unless use only rockets and an advanced surface radar and navigation autonomy system to steer the wrong landing place for one better surface to land like the ones of the american landing mode with Skycrane . If MSL success its landing, hope that ESA will follow it.

Rodolfo

[helvick]

If MSL success its landing, hope that ESA will follow it.

Some excellent points there. Does anyone know if (a) The MSL skycrane is likely to be a multi purpose design and ( what chance is there of Exomars considering it? The 2002 ExoMars\Netlander study specifies "inflatable technology" for the descent module, ie airbags.

Some further info on Exomars (also from the 2002 document available here so it maybe very out of date)
Total Rover landed mass 223kg.
Landing targets - 10-45deg latitudes (North or South).
Mission duration - 4months (main limiting factor appears to be Dust storm risk)

This proposal includes a relay orbiter and 4 netlander modules (stationary seismic\atmospheric probes with 0.5-1 year mission durations). I've seen no mention of the Netlanders in the current ESA announcements, do we know for certain that they have been canned?

[Guest_AlexBlackwell_*]

Radar Soundings of the Ionosphere of Mars
Gurnett, et al.
Published online November 30, 2005; 10.1126/science.1121868 (Science Express Research Articles)
Abstract

Just an update. Note that an updated version (v2) of the Gurnett et al. paper, which is in press waiting for assignment to a later issue, was placed online at Science Express a couple of days ago. I haven't read v2, so I don't know what, if any, changes were made.

Radar Soundings of the Ionosphere of Mars
D.A. Gurnett et al.
Published online December 6, 2005; 10.1126/science.1121868 (Science Express Research Articles)
Abstract

[Guest_paulanderson_*]

The phillosilicate sites are as follows:

1. Isemenius Lacus – slightly rougher at MOC scale than the MER sites, rare mesas, fairly featureless 34.0 N

2. Syrtis Major site – somewhat rougher at all scales compared to equivalent imagery of MER sites, lots of rampart craters, diversity of surface geological units, channel-like feature, 19.91 degrees N

3. Mwarth Vallis site – much rougher at all scales compared to equivalent imagery of MER sites, diversity of surface geological units, distinct channel-like feature, 24.54 N

4. Nili Fossae site – very much rougher at all scales compared to equivalent imagery of MER sites, diversity of surface geological units, rift-like features, mesas, dunes, possible fans 24.54 N

What about the Terra Meridiani and Arabia Terra regions, as also listed by ESA? Isemenius Lacus too? Not mentioned in the ESA list, and I couldn't find it on the Mars maps I have, even looking at 34.0 N. Are there any others that you know of?

[Guest_BruceMoomaw_*]

This proposal includes a relay orbiter and 4 netlander modules (stationary seismic\atmospheric probes with 0.5-1 year mission durations). I've seen no mention of the Netlanders in the current ESA announcements, do we know for certain that they have been canned?

http://www.aviationnow.com/avnow/news/chan...ews/12055p2.xml :

"The baseline ExoMars mission calls for a lander and rover only, to be orbited by a Soyuz 2b from Kourou. But if funding allows, an orbiter will be added, and the launch switched to an Ariane 5."

The plan the ESA developed early this year called for such a cut-rate version of the lander (I imagine they'll rely on the US orbiters for a lot of their com relay). What I have not seen yet is any indication that they're considering switching to Skycrane. Keep in mind that ExoMars is supposed to be distinctly smaller than MSL, and so they might be able to make airbags work -- although both MERs were so seriously limited in their possible landing sites because of predicted high winds, and Spirit came so close to buying the farm anyway, that I imagine they're having second thoughts.

I wouldn't mind seeing Colin Pillinger's organics package on ExoMars -- he may have been a disastrously poor judge of lander design, but his central instrument package looks well-designed to me. (By the way, the poor bastard has just been diagnosed with multiple sclerosis.)

[helvick]

I wouldn't mind seeing Colin Pillinger's organics package on ExoMars -- he may have been a disastrously poor judge of lander design, but his central instrument package looks well-designed to me.  (By the way, the poor bastard has just been diagnosed with multiple sclerosis.)

That is terrible news. I have a lot of respect for Pillingers scientific capability - it's wll beyond my capability to even begin to criticize but I am familiar with project management and he's not good at that. Unfortunately making good science happen often requires that good scientists also need to be good PM's and thats's a very rare combination.

Beagle2 had a lot of scientifically excellent components both from a scientific scope\capability point of view and from an engineering perspective. Exomars could definitely benefit from taking quite a lot of Beagle2's instrumentation as is. We'll have to wait and see but I would not be unhappy to see Exomars equipped with some variation of the Beagle2 claw.

[JonClarke]

What about the Terra Meridiani and Arabia Terra regions, as also listed by ESA? Isemenius Lacus too? Not mentioned in the ESA list, and I couldn't find it on the Mars maps I have, even looking at 34.0 N. Are there any others that you know of?

I described those 4 sites because the paper had pictures and coordinates for them.

Meridiani we know something of already. Arabia is a big place on Mars and no site was specified (unless it is Bcquerel), same with some other places mantioned - Xanthe, Isidis, Luna and Hellas. These are all very small deposits, apparently.

Becquerel is an interesting spot though, it hosts the infamous "White Rock" deposit, as well as these clays. White rock is very rough, but the craster floor is smooth, at lot will depend on how accurate the landing system is I guess, and how well it copes with hazzards.

Isemenius Lacus is a classic dark albedo feature. The nearest "real" feature is Isemeniae Fossae. The clay patch seems to be in the middle of the crater Focas.

With respect to ExoMars, there seemed to be quite a bit of support for the idea of equipping it with a PAW at the April EGU. Plus my recollection is that the airbags being considered are the so-called "deadbeat" type, that almost immediately deflate on impact, rather like those of a car. Since the CEV is supposed to have this type as well it suggests that this approach can handle much heavier loads than the bouncing type.

Jon

[edstrick]

"Becquerel is an interesting spot though, it hosts the infamous "White Rock" deposit..."

Becquerel has a white-rock like deposit, but not "White Rock" That is located in a crater in Sabeaus Sinus, east of Sinus Meridiani and East of the Schiaparelli Basin. There are a number of craters in the Oxia Palus region east into Arabia that contain erodable layered deposits. Henry Crater in Arabia has the largest, there's another smaller one nearby. The White Rock deposit is much more noticable than the others, as it's in a low albedo region and has high contrast with the dark more or less basaltic sands in those regions. The others are in intermediate to high albedo regions.

[RNeuhaus]

I have another concern on ExoMars telecommunication capability since it will carry only UHF and it will be relying on American-European orbiters for the communications.

It is lacking the redundancy for any emercengy. I think ExoMars must bring another telecom equipment as a Low Gain Antena (Beacon Mode) in which it would be very useful for just in the case of any emergency that any orbibers are available or disponible for any reason. By incorporating the HGA would be much better but it is up to the ESA to evaluate about the benefits and costs. According to MER experience, the HGA was not very much utilized (less than 3% of cases).

The additional weigth and cost will be compensated by the robustness of the mission.

Rodolfo

[djellison]

Come '11, there will be MRO (almost certainly), MEX (almost certainly), MO (probably) and potentially another orbiter at Mars. Relay capacity isnt going to be a problem imho.

I agree though - DTE tones during EDL are VITAL.

Doug

[Guest_AlexBlackwell_*]

I agree though - DTE tones during EDL are VITAL.

From a programmatic standpoint, yes (i.e., for future missions). However, EDL telemetry, whether DTE or relayed to Earth via orbiters (with latency, of course), has very little if any operational value for that particular mission.