A nice New Year's post starting the year with a question (and answer!) on the fabulous high resolution stereo camera (HRSC) image of Orcus Patera, first published by ESA (here) in 2010, and reposted as the Image of the Day on 31 December 2011 at the Mars Travel blog. Best wishes to everyone for a healthy and successful 2012. Details below! -- Daniel

First, here's the image (click image to access the original post in ESA web):

 

  Click for hi-res version

Orcus Patera is an enigmatic elliptical depression near Mars’s equator, in the eastern hemisphere of the planet. Located between the volcanoes of Elysium Mons and Olympus Mons, its formation remains a mystery. Often overlooked, this well-defined depression extends approximately 380 km by 140 km in a NNE–SSW direction. It has a rim that rises up to 1800 m above the surrounding plains, while the floor of the depression lies 400–600 m below the surroundings.

Earlier today, Mars Travel blogger David Geaney sent in a question: 

If you look at one of the central craters in Orcus Patera using the HRSC image, you will see there is something blue in the crater. What is the blue material? Thank you for your time and patience.

We passed the query to Mars Express project scientist Olivier Witasse, who wrote:

Hi David,

The blue is not a lake....

It's dust, which emits in the blue part of the spectrum. In the data processing, the blue part is somewhat enhanced, which sometimes creates a wrong impression.

Cheers,

--Olivier

 

 

A comment today from Mars Express Spacecraft Operations Manager Michel Denis on this week's report: "MARSIS completes measurement campaign over Martian North Pole." The report gives good news!

"The Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) instrument on board Mars Express has recently completed a subsurface sounding campaign over the planet's North Pole. The campaign was interrupted by the suspension of science observations several times between August and October due to safe modes and to anomalies in the operation of the spacecraft's Solid-State Mass Memory (SSMM) system. As MARSIS best observes in the dark, which for the North Pole only occurs every few years, it was among the first instruments to resume observations once a partial work-around for the problems had been implemented."

In his comment below, the 'FAST Method' that Michel refers to is the operations team's newly developed way of uploading commands to Mars Express, which avoids using the problematic Solid State Mass Memory (SSMM) for critical commanding.

The 'File-based Activities on Short Timeline' method essentially means that commands are grouped in very short self-contained files that can be loaded safely, in advance of execution, from the SSMM into an alternative memory unit (that is reliable but not as capacious as the SSMM).

Michel writes:

The FAST method - loading short command files upon need into the short onboard mission timeline - was put into use at the end of October 2011 with the (excellent) result that we could save what was remaining of the North Pole observation campaign by the MARSIS radar.

The net loss in data collection was mitigated by using the existing MARSIS command sequences as soon as possible. Meanwhile, as for the other instruments, new MARSIS on-board control procedures (OBCPs) are under development and will allow operation with fewer commands, therefore enabling the operation of several science instruments in parallel.

My main point? We did our job: contrary to widespread received wisdom, the spacecraft operators' role is not to simply watch over (supposedly) boring routine operations during the many long years of a mission - nor simply saving a spacecraft that experiences problems. In fact, we are relied upon to deliver safely as much of the expected (precious) scientific data as possible within the resources available - despite adversity. And that's what we're doing!

This in this morning from Jonathan Schulster on the Mars Express operations team:

The ASPERA (Energetic Neutral Atoms Analyser) instrument high voltage (kV) lines and equipment were successfully switched on today, a few minutes ago at Mars (~09:57 CET), using the new on-board control procedures (OBCP).

These will run for one hour until 10:40CET today and the ASPERA science team will examine the recorded science data before giving the 'go-ahead' for full operations of ASPERA using only OBCP's starting 9 Jan uary 2012.

Cheers!

- Jonathan Schulster
Mars Express Mission Planning & Flight Control Team

Looks like another instrument is set to return to action! -- Daniel

Mission controllers are making excellent progress in returning Mars Express to routine service. Some science activities have already resumed after being temporarily suspended last month following a series of faults related to the onboard data storage system.
 
Having arrived around Mars in December 2003 for an initial two-year mission, the spacecraft is now in its eighth year of science operations. It has returned some of the most stunning images and valuable science data ever obtained from the Red Planet.

In mid-October 2011, anomalies in the operation of its Solid-State Mass Memory (SSMM) system caused science observations to be temporarily halted.

Full story via ESA web

Anomalies in the operation of the solid-state mass memory system on board Mars Express have caused science observations to be temporarily halted. A technical work-around is being investigated that will enable the resumption of a number of observations and should evolve into a long-term solution.

In mid-August, Mars Express autonomously entered safe mode, an operational mode designed to safeguard both the spacecraft itself and its instrument payload in the event of faults or errors.

The cause of entering the safe mode was a complex combination of events relating to reading from and writing to memory modules in the Solid-State Mass Memory (SSMM) system. This is used to store data acquired by the instruments and housekeeping data from the spacecraft's subsystems, prior to its transmission to Earth, and is also used to store commands for the spacecraft that have been received from the ground stations, while awaiting execution.

More details in ESA's Science & Technology site.

Earlier this month, ESA’s Mars Express performed a special manoeuvre to observe an unusual alignment of Jupiter and the martian moon Phobos. The impressive images have now been processed into a movie of this rare event.
 
At the moment when Mars Express, Phobos, and Jupiter aligned on 1 June 2011, there was a distance of 11 389 km between the spacecraft and Phobos, and a further 529 million km to Jupiter.

Full article via ESA.

A nice wrap-up on Mars Express achievements today!

Mars Express Spacecraft Operations Manager Michel Denis sent in anote pointing out that, according to ScienceWatch.com, in the 'Top 10 papers on planetary science of the last 10 years', the most-cited papers (5 out of 10) are from Mars Express data and scientists (ranking 1, 2, 4, 6 and 9). In the same list, quite a number of papers are Cassini- and Huygens-related. Full details via: http://www.sciencewatch.com.

As Michel mentions, this is a nice continuation of the 'Top 10 Science Insights of the Decade' in the magazine Science (December 2010) where, with all sciences together, 'Wate on Mars' appears as one of the ten (with Mars Express mentioned by name!). -- Daniel

A few days ago, Dan Brennen, of Elk Grove, California, posted a very nice animation in the UnmannedSpaceflight.com forums and we are delighted to share this below. Dan sent us a description:

The animation was created using the sequence of 5 images located here which were scaled down to 1/5 size. A simple morphing program was utilized to create the intermediate images which allow for the appearance of motion. Approximately 30 control points were identified to tell the program where the limb had changed shape and key features on Phobos had moved between images. Each transition from one image to the next contained 200 steps, which was later compressed to 8 frames per second to create the final image file.

I'm sure you can guess that the quality would improved with more control points and more precise placement of those control points. But it's quite time consuming, especially with five images. So I did this with less time and effort in order to quickly create an interesting feature for our forum in just an hour or two while I had my Saturday morning coffee.

 Thanks, Dan, for some great work! -- Daniel 

 

Original animation via UnMannedSpaceFlight.com Original HRSC images: Copyright ESA/DLR/FU Berlin (G. Neukum). Animation credit: Dan Brennan, Elk Grove, California

 

 

Emily Lakdawalla over at the Planetary Society Blog has posted a very detailed explanation of how the Mars Express High-Resolution Stereo Camera (HRSC) works, with some very informative examples and descriptions from this month's Phobos flyby. Emily writes:

But what I think is best about this particular set of images is that they serve as really great illustrations of how HRSC works. It's an unusual instrument: a pushbroom camera that acquires simultaneous stereo and color data with a higher-resolution framing camera bolted to it. If you don't understand what that preceding sentence means, bear with me; I'll explain.

Access Emily's full post in The Planetary Society Blog. 

 

The team here were delighted to see that the Mars Express HRSC image of Phobos had been selected as NASA's Astronomy Picture of the Day (APOD) yesterday! Thanks guys!

Click on the image below to access the APOD site --> and scroll down and click on the link to vote for APOD's 'Astronomy Picture of the Year 2010'. -- Daniel

This just sent in yesterday evening by ESA's Olivier Witasse, the Mars Express Project Scientist, with details on PFS results from the Phobos flyby.

Credits: ESA/ASI/INAF-IFSI/PFS team 

The figure above (click for large size) shows the spectrum of Phobos acquired by the PFS instrument during the flyby on 9 January 2011 (Mars Express orbit 8974).

The x-axis represents the wave number, in other words the wavelength, in the infrared. The y-axis represents the radiance, a physical quantity proportional to the brightness. The data are in black (note the uncertainty is also shown), while the red curve is an interpolation to the data.

Olivier sent in a note, stating:

PFS on Mars Express detects Phobos!

The Planetary Fourier Spectrometer (PFS) on board Mars Express successfully observed Phobos during the close flyby performed on 9 January 2011. The instrument collected data in thermal and near infrared wavelengths, with a spectral resolution of ~1.3 cm-1. Phobos was well illuminated during the flyby, ensuring good quality data.

The figure shows a preliminary calibration of the spectrum of Phobos acquired during the flyby. The spectrum shows a clear absorption feature around the wave number 600 cm-1 (corresponding to a wavelength of 17 µm), which was already visible during previous flybys. This feature (and other less-pronounced absorption bands visible in the spectrum) will help investigations into the surface composition of Phobos.

The general shape of the spectrum allows scientists to deduce the surface temperature; a preliminary estimate for this observation indicates a surface temperature of ~ -57 Celsius.

Further analysis is required to improve the calibration and the calculation of the geometry for these new observations. Subsequent surface temperature and composition analysis will be carried out.

We received late yesterday the processed images from the High Resolution Stereo Camera (HRSC) science team and they are fabulous! The HRSC team have provided an excellent set of images and captions showing a 3D view of the moon and the proposed landing site of the Phobos-Grunt mission.

-- Stuart & Daniel

Note: Each of the images below links through to a high-resolution (TIFF) file.

---

 

The first image shows the geometrical relationships between Mars, Phobos, and Mars Express at the time of the sequence. Copyright ESA/DLR/FU Berlin (G. Neukum).
 

 

 

 

Stereo-1 channel image of Phobos: his image has been photometrically enhanced to illuminate darker areas. Resolution: 4.1 meters per pixel. Image: Copyright ESA/DLR/FU Berlin (G. Neukum).

 

 

 

3D Image (red-cyan anaglyph): The HRSC camera recorded images of Phobos on 9 January 2011 at a distance of 100 km with a resolution of 8.1 m/pixel. Due to the stereo viewing geometry during the flyby, a small part of the moon’s edge is only visible for the right eye resulting in an odd 3D-perception in this area. This part has been slightly adjusted for better viewing. Also, for the left eye at the left edge of the image four small data gaps have been interpolated. Image: Copyright ESA/DLR/FU Berlin (G. Neukum).

 

 

 

SRC Images: Superimposed on the HRSC nadir image are 7 SRC images with a resolution of about 3 m/pixel. The Super Resolution Channel images show more details of the surface of Phobos. Image: Copyright ESA/DLR/FU Berlin (G. Neukum).

 

 

 

 

Sequence of 5 HRSC-channels, orbit 8974: (left to right) stereo S1 (4.1 m/pixel), photometric P1 (8.1 m/pixel), nadir ND (3.9 m/pixel), photometric p2 (8.2 m/pixel), stereo S2 (4.3 m/pixel). Image: Copyright ESA/DLR/FU Berlin (G. Neukum).

 

 

 

Planned landing site of the Russian Phobos-Grunt mission: Image of Phobos with a resolution of 8.2 m/pixel in orbit 8974. The ellipses marked the previously planned (red) and currently considered (blue) landing sites for the Russian Phobos-Grunt mission. Image: Copyright ESA/DLR/FU Berlin (G. Neukum).

 

 

Further information:

Markus Bauer
ESA Science and Robotic Exploration Communication Officer
Email: markus.bauer@esa.int
Tel: +31 71 565 6799
Mob: +31 61 594 3 954

Olivier Witasse
ESA Mars Express project scientist
ESTEC, The Netherlands
Tel: +31 71 565 8015
Email:  owitasse@rssd.esa.int

Univ.-Prof. Dr. Gerhard Neukum
Freie Universitaet Berlin
Fachbereich Geowissenschaften
Fachrichtung Planetologie und Fernerkundung
Mobile: +49 171-7647177
Telefon: +49 30 838 70579; +49 30 838 70575 (Sekr.)
Email:  gneukum@zedat.fu-berlin.de

Prof. Dr. Ralf Jaumann
Deutsches Zentrum für Luft- und Raumfahrt (DLR)
Institut für Planetenforschung, Planetengeologie
Tel.: +49 30 67055-400
Fax: +49 30 67055-402
Email:  ralf.jaumann@dlr.de
 

 

 

This note and images were just sent in from the MARSIS Team - it appears they did in fact receive some nice returns during Sunday's Phobos flyby. The instrument's 40-metre long antenna is usually used to send low-frequency radio waves towards Mars, which are then reflected from any surface they encounter.

The team wrote:

The multi-frequency sounding radar MARSIS successfully observed Phobos during the latest Mars Express science campaign on 9 January 2011.

MARSIS collected two segments of data containing 6000 individual echoes, acquired in 50 sec of operation. The distance from Mars Express to Phobos was in the range 180 to 230 km, using a frequency of 4 MHz.

The ground track covered new areas not explored by previous flybys. From a first analysis of the topography and based on previous experience, the layered appearance of the image, also called 'clutter' is caused by delayed radar reflections from the surrounding Phobos surface shape.

Fig. 1 (scroll down) shows the radargram of the first segment of the flyby. The top white line is the surface signature of Phobos, while the clutter or sub-surface contributions are the bottom ones.

Ground processing of the data for one single frame, is shown in Fig. 2 with a Signal-to-Noise Ratio (SNR) of about 18 dB. The first peak represents the Phobos surface, while the second one could be either clutter or subsurface returns. The distance between the two main peaks in time is about 5.7µs (microseconds).

Further and more accurate analysis will now be done to improve the signal to noise level and the range resolution, allowing a better science interpretation.

- The Marsis team

 

 

Figure 1

 Figure 2

A quick update from the Mars Express team here at ESOC: based on telemetry and information downloaded after the 9 January Phobos flyby, the spacecraft completed the flyby according to plan. Mars Express is healthy and the team are now waiting for science data to be downloaded over the next ten days.

The data will be passed to the various instrument teams for analysis, and, according the ESA's Mars Express Project Scientist Olivier Witasse, we expect to have the high-resolution images later in the week of 17 January. -- Daniel

 

 

Our sincere apologies to all who tried to follow the progress of Mars Express on 9 January - our system went down and was only restored this morning. :-(

To see the real-time updates from yesterday, access the ESA page in Facebook - which served as a handy if somewhat unplanned back-up platform! We will check with the Mars Express team here at ESOC later today and get an update out to you here in the blog. -- Daniel