Successful landing on Mars
Monday the 6th of August. The time is 6:30 here in Denmark and NASA’s rover Curiosity is scheduled to land within the next hour. Danish researchers from the Niels Bohr Institute are part of the project and Morten Bo Madsen, head of the Danish Mars research group, is at NASA’s control centre in Pasadena, California, from which he will report back to the Tycho Brahe Planetarium where hundreds of people have gathered to follow the landing.
The rocket was launched on the 26th of November 2011 and after a journey of 566 million kilometres through space the lander with the rover Curiosity is now approaching Mars. We are following the landing on NASA-TV, with commentating by Kjartan Kinch, one of the researchers in the Danish Mars group at the Niels Bohr Institute.
“Stand by 1,” sounds it from the landing team in NASA’s control centre. Kjartan Kinch explains that the probe is now 1 km from the surface – 500 meters, now things are moving quickly. But the information from the probe is delayed 14 minutes because of the great distance, so the probe has probably landed – we just don’t know it yet.
Suddenly the connection to NASA is lost. Then an SMS arrives from Morten Bo Madsen “Dear all, it has succeeded, it has landed.” The connection is restored and there is wild jubilation in NASA’s control centre. The landing team has completed their work. Now the approximately 300 researchers and engineers get on with their work – the exploration of Mars.
Exploring Mars’ past
The rover Curiosity has now landed exactly as planned in the large crater, Gale, which lies between the northern and southern hemisphere. The giant crater is 154 kilometers in diameter and the sides of the crater are 5 kilometers high. Lying in the middle of this crater is a mountain, Mount Sharp, which is approximately 5.5 km high. Morten Bo Madsen explains that the area is particularly interesting because in the lowermost layers of Mount Sharp you can find some of the oldest sediments from the planet’s past more than 3½ billion years ago, when the environment was completely different than today. Back then there was liquid water on the surface of Mars and the aim of the project, among other things, is to examine the sediments for organic compounds, which are a prerequisite for life.
The Red Planet
The Danish Mars researchers are particularly interested in examining the Martian dust. The results of studies from previous Mars missions have shown that the dust and the soil on Mars are magnetic because they contain the ferrous mineral magnetite. But why is it red? The research results have shown that the larger dust particles in particular are magnetic, but not those that are the most red. These are the very fine small dust particles and one explanation could be that a component of the dust could contain aqueous minerals and it is this component that seems to be the cause of the dominant colour of the dust and the planet.
The experiments will be carried out by the rover Curiosity, which is the size of a small car. It weighs almost 900 kg and has 75 kg of instruments on board including an x-ray diffractometer, which can analyse samples of dust.
“There is not much of the fine dust in this area and we need approximately 200 milligrams to study it in the diffractometer. We must therefore first select an area from the Rover’s images that looks to be dusty and will shoot at the ground with a laser. By analysing the spectra of the light that is formed when you shoot a laser at the ground you can determine the elemental composition and this can tell us a lot of interesting things. We can then get the rover to drive over to the area and take a sample, which is placed in the x-ray diffractometer that sits inside the rover. It is a bit complicated to get a sample with a lot of the very finest dust, but we hope it succeeds,” explains Morten Bo Madsen, who cannot hide the fact that he thinks it’s cool to be on a mission again.
The Danish Mars group is comprised of seven researchers with different specialties, including nano-geoscience and studies of organic molecules and studies of minerals with an x-ray diffractometer.
The plan for the rover to drive around and investigate the plains and the lower layers of Mount Sharp for at least one Martian year, equivalent to two Earth years.