Mars seen yesterday

Today's post contributed by Mars Express operations engineer Simon Wood – Ed.

Here in our latest Mars Webcam images taken yesterday, 4 June, we have not only captured more shots of the northern polar cap and what seems to be further dust/cloud formations around the pole, we have also snapped some of the biggest geological features on the planet.

Mars seen by VMC on 4 June 21014. Credit: ESA/Mars Express/VMC

Mars seen by VMC - with annotations - on 4 June 21014. Credit: ESA/Mars Express/VMC

In this image, we have all three volcanoes that make up the Tharsis mountains.

These three volcanoes dwarf anything found on Earth, ranging from 14 to 18 km in height. To put this into perspective, the tallest volcano on Earth is Mauna Loa in Hawaii, which only reaches 9 km above the ocean floor.

However, the Tharsis mountains are themselves dwarfed by the largest volcano on the Red Planet (and indeed in the solar system), Olympus Mons, which has an approximate height of a staggering 25 km!

The favourable lighting conditions in yesterday's observation enabled the entire base of the volcano to be visible and if you look closely you can even make out the crater. Olympus Mons covers an area of around 300 000 square kms, which to give some indication of the scale, would cover most of France.

We also just see the edge of the 'Grand Canyon of Mars' the Valles Marineris running along the limb of the planet (hopefully we'll have more on that in a forthcoming observation).

And here's a very cool Valles Marineris fly-through video:

One further item we've tagged in our image is the landing site of NASA's Phoenix spacecraft, the first spacecraft to send back science data from the Martian poles.

NASA Phoenix on Mars. Credit: NASA/JPL/Corby Waste

NASA Phoenix on Mars. Credit: NASA/JPL/Corby Waste

In May 2008, Mars Express provided communication relay support to Phoenix using MELACOM, our UHF radio, recording its radio signal during the entry, descent and landing phase (just as we would later do for Curiosity in 2012).

Some further relay tests were performed once it was successfully on the surface, with our last contact completed on 31 May 2008.

As usual all the images are available on the VMC flickr account:

Mars Full Orbit Video 2.0: Kepler rocks the Red Planet

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.

What's the 'Full Orbit video', you ask? Access the original FO video produced in 2010 for the full description.

Thanks to the Mars Express Science & Operations teams for generating a fabulous, unique-in-our-Solar-System view of the Red Planet.

Happy Birthday, Mars Express!

Mars Express flying through the blackout – Solar Conjunction 2011

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