Ian Barnett takes a look at this month’s Science news.
The Mars Express, a spacecraft of the European Space Agency, has found evidence that an ocean once covered parts of the Martian surface billions of years ago. Sediments, resembling an ocean floor, and indications of stretches of shoreline provide evidence for this theory. The craft is also scanning for water or ice underneath the planet’s surface, having found ice deposits in the aforementioned sediments. Scientist postulate the existence of two oceans on Mars: one four billion years ago, when the planet experienced a warm, wet period, and one three billion years ago, after an impact that melted much of the surface ice, creating an ocean. These oceans were short-lived however, with the latter lasting for only around a million years. The question remaining unanswered is “where did all the water go?”
Plant sunscreen found
A team of researchers who have spent 15 years studying why plants are not damaged by the sun have revealed their results. They found that a complex series of responses, controlled by a UV sensing protein called UVR8, combats the damaging effect of sunlight. When it senses strong sunlight, it sets off a chain of responses that lead to the production of enzymes that repair DNA. The scientists also showed that plants that were missing this protein grow poorly in strong UV-B light; the wavelength of light responsible for tanning in humans. Principle investigator Prof. Elizabeth Getzoff said “It’s the plant equivalent of putting on sunscreen!”
The first accurate satellite study into glacier recession in the Himalayas has revealed some surprising results. Research has shown that less than 10% of the estimated ice lost from the area has actually melted away. The disparity is thought to have arisen because much of the previous ground-based study was carried out at lower, warmer altitudes where glaciers were melting at a reasonably fast rate. However, when these results were extrapolated up the mountain range, the simple fact that glaciers at higher altitudes were not melting at the same rate was not taken into account. Previous worldwide data, which had even been supported by the UN Intergovernmental Panel on Climate Change, seems to have also grossly overestimated the rate at which ice is melting. Nevertheless, it is unclear whether these new findings have the power to challenge the decades of evidence and thousands of scientists supporting the global warming hypothesis. One thing is for sure: these new findings will certainly add fuel to the global warming cynics’ fires, despite having been discovered by two boxes in the sky!
Silver shines as cancer drug
Molecules containing silver have been shown to be effective against cancerous cells in a recent study carried out at the University of Leeds. The study showed that silver compounds had a similar effect on both breast and colon cancer cells as the widely used cancer drug cisplatin does. Cisplatin is already employed in the treatment of several forms of cancer, but because platinum is used in the drug, there are some harmful side-effects. Platinum’s toxicity in the body can produce effects ranging from hearing loss to kidney and nerve damage. It is hoped that a silver-based drug could provide the same benefits as cisplatin, but with fewer side-effects, since silver has a lower toxicity towards normal cells than platinum.
Could an Antarctic lake contain new life?
A Russian team have breached Lake Vostok in Antarctica, after drilling through 3000 metres of ice. The huge expanse of water remains fluid due to heat radiating up from the centre of the Earth. The lake, which is concealed underneath a glacier, has remained untouched for over 14 million years and it is hoped that evidence of new life forms will be found, along with the possibility of unearthing information about the feasibility of life on other planets. Scientists cannot, however, take samples immediately, since water may have been contaminated by drilling fluid – a fact which Greenpeace is appreciably outraged at.
Image 1 – Denni
Image 2 – Koustuvk