Strawberries in space

You’re speeding through the icy depths of space, millions of miles from Earth, when you realise you’d like a snack to remind you of the long summers of home. What do you do? Bizarrely, the answer might be as simple as going to pick some strawberries.

UK brought low by Arctic high

The weather outside is frightful... Image: NASA

The picture above, taken by NASA’s Terra satellite on the 7^th January, shows the completely snow-bound state of the UK. This winter, temperatures have regularly fallen below -10^oC in some parts of the country, and heavy snow has closed roads, schools and businesses. But why is this year so much colder than usual?

Globally, it isn’t. While the UK, parts of North America and China are suffering in the cold, other parts of the world, including the Mediterranean and Siberia, are experiencing unseasonal warmth. The cause of this confusing weather is an area of unusually high atmospheric pressure over the Arctic, which is driving colder air southwards towards northern Europe.

The changes in air pressure over the Arctic are known as the Arctic Oscillation (or AO, for short). It swings between positive (low pressure) and negative (high pressure). This year, the AO has become very ‘negative’, resulting in the freezing conditions some of us are shivering through at the moment.

One thing this cold weather doesn’t affect, however, is the reality of our changing global climate. Regional weather variations like this do not discredit the long-term climatic warming trend scientists from around the world have observed: the blame for which lies squarely with man’s increasing CO₂ emissions.

‘Buckets’ of water found on moon

NASA scientists have found large quantities of water in the debris thrown up by the LCROSS spacecraft, which was deliberately crashed into the moon last month.

The lunar south pole, perfect place for an (indoor) swimming pool? Image credit: NASA

The finding tells us much about our nearest neighbour, and its potential role in space exploration: the presence of water ice on the moon is vital for future lunar exploration. It could supply drinking water, oxygen and rocket fuel, which opens up the possibility of permanent lunar settlement.

LCROSS, which stands for Lunar CRater Observing and Sensing Satellite, slammed into the Cabeus crater at the moon’s south pole. The bottom of the crater never sees sunlight and is the ideal place to look for hidden water ice, which may have lain undisturbed for the past billion years. LCROSS hit the crater floor in two stages: the first was the expended upper stage rocket, called Centaur, used to get the spacecraft into position for its collision. Following close behind was LCROSS itself. LCROSS was loaded with cameras and spectrometers to record the results of the first impact before it too hit the lunar surface four minutes later.

Although it perhaps wasn’t the most elegant experiment ever conducted, it seems to have achieved all its designers hoped for. Data from spectrometers aboard LCROSS confirmed the presence of water in the material thrown up by the impact. Spectrometers look at the light emitted or absorbed by a substance, as this gives a clue as to what it is made of. The LCROSS data contained the unmistakable signature of water. And it wasn’t just a trace of water: the scientists believe the signal corresponds to around 100kg of water (or ‘a dozen two-gallon buckets’, according to one researcher on the BBC), suggesting there is more than the occasional frozen puddle to be found in the dark corners of the moon.

Many people were disappointed with the initial results of the LCROSS mission. The 2,200kg spacecraft was expected to create a plume of material around ten kilometres high and visible from Earth as it was illuminated by the sun. Instead, the plume was much smaller, only reaching one and a half kilometres above the lunar surface. This was still enough to advertise the presence of water to the cameras on LCROSS.

See the little grey blob? Thats the plume of dust and ice. Unimpressive, perhaps, until you notice the scale bar! Image credit: NASA

Moon Shots

The Apollo 14 landing site.

This picture, taken last week by NASA’s Lunar Reconnaissance Orbiter, shows the site of the Apollo14 moon landing. As far as I’m aware, these are first ever detailed images of the Apollo landing sites, and they only represent a rough test of the imaging capabilities of NASA’s latest lunar mission. Future images should be impressive indeed!

Visible across the centre of the picture are the tracks left by the astronauts as they walked between the Apollo 14 lander on the right (see that small rectangular shadow?) to a small pile of equipment on the left. If it’s not obvious, I’ve included the magnified and annotated version, below.

See it yet?

The NASA Lunar Reconnaissance Orbiter (LRO) website includes images of the other Apollo landing sites, including Apollo 11.

These images are only a taste of things to come. The LRO hasn’t yet reached its final position in orbit around the moon. When it does so in August, it will be able to take much more detailed pictures to help NASA find landing site and identify valuable resources – both vital if we are ever to return to the moon.

Credit for both images is (of course):  NASA/Goddard Space Flight Centre/University of Arizona