Just in time to celebrate the 10th anniversary of Mars Express: a new and enhanced Full Orbit Video delivered by the VMC camera - the Mars Webcam!
The version below is a special 'MEX birthday preview' – we'll post a somewhat extended version late next week (along with a more detailed explanation on how this video was produced), to coincide with the next expected VMC image set arriving from Mars.
Some nice news today for VMC fans: the teams at ESOC are getting closer to restoring the VMC back to operation. Imaging stopped, of course, with last autumn's anomaly, the solution of which has kept everyone in the MEX family fully occupied for several months. VMC, being last priority, was not worked on. But we're hopeful that we'll get a solution soon, and we'll post news here as soon as we hear anything.
References to our very own VMC camera activities highlighted - and note very nice comments on teamwork! Click here to read the full report.
While full science operations have now been resumed, a number of tasks remain to be completed. Most important among these is the implementation of an OBCP scheduler. This will enable the spacecraft to operate autonomously for up to a week, compared to the few days that are possible with the current FAST system. Work is also in hand to resume operation of the Visual Monitoring Camera.
Enormous team effort
Completely redesigning the way in which Mars Express is controlled has involved an enormous amount of work for the mission control team at the European Space Operations Centre (ESOC), assisted by their counterparts at the European Space Astronomy Centre (ESAC), PI-teams, other ESA experts and partners in industry. Everyone involved with the mission is extremely grateful for their hard work.
Although the 'Express' in Mars Express highlights that the mission was developed in a short time and with a relatively modest budget, the ability to resume full operations after a very serious failure shows that the resulting design is both robust and flexible.
Mars Express has now been restored to full operational capability and its potential mission lifetime remains unchanged.
This paper discusses the possibilities for using the non-scientific Visual Monitoring Camera (VMC) to contribute to this scientific objective of the Mars Express mission, complementing and supporting the data obtained from the scientific payload. The contribution of VMC is that it can image the planet with a large field of view, providing the context for the other experiments which operate at lower altitudes, close to the pericenter. The VMC data would also allow providing useful information such as cloud altitude (thanks to the shadow) morphology, relative reflectivity and dynamics. These are important parameters in the characterization of the CO2 cloud population.
You might have noticed that VMC – the Mars Webcam – has been quiet recently. Don't worry: it's all expected – it's just further proof of the challenges and excitement of planetary spaceflight!
Today, Mars is at the worst point of a period known as 'solar conjunction', which means that Mars is on the exact opposite side of the Sun from Earth. Seen from the Earth at around 16:00 today, Mars appears only 0.7658 degrees from the Sun – less than the width of your finger held at arm's length!
This results in major disturbances in our communications from Earth to Mars Express and back; as a result the spacecraft has been put into an autonomous operations mode, with all activities on hold until we come out the other side.
The video above shows the Sun from the start of this year until today – with the streamer-like tendrils of its atmosphere, the corona. Coming in from the left of the video is a bright speck – Mars! Invisible here is the tiny dot of Mars Express orbiting the red planet. Our problem communicating with Mars Express comes from the fact that the radio beam from the spacecraft has to pass through this atmosphere, getting distorted on the way.
On top of that, our dish antennas on Earth have problems picking out the weak signal from Mars Express from the 'noise' of the Sun. All of this makes this period, about a month long, especially challenging for communications with all Mars missions.
To keep the spacecraft safe, we have to give it enough information for it to look after itself for the month when we are passing behind the Sun. There's simply not enough memory on the spacecraft to also include instructions on how to carry out its normal activities (including VMC imaging!) – all the space is used up with our commands on how to look after itself for a month alone, out of contact with Earth!
The video above was produced using the excellent JHelioViewer tool, developed with funding from ESA and NASA.
It shows in blue and red the view from the LASCO instrument on the ESA/NASA SOHO solar observatory mission. This instrument puts a disc in front of the Sun to block the direct light, and what can be seen is the corona, and in this case, Mars passing behind it. In the centre are images from the NASA Solar Dynamics Observatory AIA instrument, showing the blazing Sun in the middle of our solar system. – Thomas