Water on the moon and on Mars has been hot news over the last couple of weeks.
The surprise with the moon has been that small quantities of water have been detected all over the moon, and not just at the poles.
Three different space probes have confirmed these results, the latest being the Indian spacecraft, Chandrayaan-1, which was carrying a US National Aeronautics and Space Administration- (Nasa-) built moon mineralogy mapper (M3).
The M3 detected a small quantity of water all over the moon. Since the mapper could only penetrate the top few millimetres of the moon’s surface, the evidence of water came as a surprise because, until now, the top layer of the moon’s dusty surface was assumed to be bone dry.
The observations of the M3 device were confirmed by previous missions, namely the Cassini, which passed the moon in 1999, and the Deep Impact Spacecraft. The latter is still on its way to its final mission, which is to crash into a comet 103P/Hartley, the target date for the impact being November 2, 2010.
But as the Deep Impact Spacecraft passed the moon, it used its detectors to ‘look’ down on the surface. All three spacecraft confirm the findings.
It is still the case that scientists expect to find quite large amounts of water in the craters at the poles of the moon.
More excitement is only weeks away because two other spacecraft are now on their way to the moon with the specific intent of looking for water. They are Nasa’s Lunar Reconnaissance Orbiter and the LCRoss impactor, which are going to explore the lunar south pole craters, looking for water ice.
However, the recent find has thrown up other information as well, and that is that the water signature varies, depending on the time of day, being strongest in the early morning and weakest at midday.
This indicates that the water is not static – something happens during a day cycle, and this then provides a mechanism for water to migrate to the poles.
This mechanism would explain why the poles indicate large volumes of water compared with the equator.
So why is this so important? Well, as the old saying goes, water is life.
A major challenge in planning for a manned moon base has been how to supply astronauts with water. Currently, the astronauts in spacecraft, such as the International Space Station (ISS), drink their own urine. Of course, it is recycled back to clean water before they drink it, but water is so valuable that every drop is saved.
Water on the moon in reasonable quanti- ties would be a major factor in being able to build a moon base that is permanently manned, much like the Antarctic research bases of today.
A day after the announcement regarding water on the moon, another water announcement followed – this time, it concerned the planet Mars. Much more water has been found on Mars than previously thought. Another spacecraft, the Mars Reconnaissance Orbiter, has shown clear evidence of huge subsurface ice sheets extending from the poles halfway to the planet’s equator. What is more exciting is that the ice is very pure, being about 99% water. Previously, it was thought that the water would be about half ice and half dirt.
In August 2008, members of the Mars Recon- naissance Orbiter’s team examined images and were surprised to see bright blue mate- rial poking up from the bottom of a crater. It turned out to be ice, but it soon disappeared with the warmth of the sun.
Now the spacecraft has examined the bottoms of five newly formed craters and found a large quantity of ice.
There are clear indications that water once flowed on Mars, so, perhaps, there used to be rivers and lakes there. Ken Edgett, a member of the Space Science Systems team, in San Diego, in the US, has said that they estimate that the total water ice on Mars is equal to the volume of the Greenland ice sheet on earth. That is a lot of water.
Such findings also alter the entire picture for the planning of manned bases on Mars.