/ 22 November 2013

Science briefs

Science Briefs

SA satellite could fit in your bag
They’re small, slinky and the latest trend in space observation technology: nanosatellites called CubeSats. On November 21, South Africa launched its first CubeSat, joining the likes of the United States, Japan, the Netherlands and Canada, among others. At 10x10x10cm and weighing only 1.2kg, ZACube-1 will orbit the Earth 15 times a day and run on the same amount of power as a 5W light bulb.

Designed and built by postgraduate students of the French South African Institute of Technology at the Cape Peninsula University of Technology, in collaboration with the South African National Space Agency, ZACube-1 is fitted with a high-frequency beacon that will transmit a signal back to stations in South Africa.

Using this dinky spacecraft, which could get lost under a pile of papers on your desk, space scientists will monitor the ionosphere, a charged upper layer of the atmosphere, which makes global positioning systems, long-wave radio and cellphone communications possible. Signals "bounce" off the ionosphere and come back to Earth – without it they would continue travelling out into space. The university says that they are already working on the next CubeSat.

Cradle yields fossil riches
In a cave in the Cradle of Humankind, adorned with helmets and flashlights, six slim scientists continue to excavate what the University of the Witwatersrand’s Professor Lee Berger describes as a ­"spectacular" fossil find. This week, the Rising Star Expedition, a collaboration between Wits University and National Geographic, tagged its 450th fossil.

The cave, about 30m ­underground, has a small entrance, and only small-chested people – who also happen to be experienced climbers – can enter it. Although he will not say what fossils the team has found, Berger has described them as ­"vulnerably exposed". "I realised history would not judge me well if we delayed the excavation." For live updates, follow National Geographic’s Rising Star Expedition blog.

Mapping cancer
According to the World Health Organisation, about 70% of ­cancer deaths occur in developing ­countries, but there is little hard data to explain where these cancer hot spots are and what kinds of cancer people are suffering from. IBM last week announced that it was working with the Union for International Cancer Control (UICC) to develop a cancer registry, starting with sub-Saharan Africa. "Much of the world is tracking the growing burden of cancer with very incomplete information," said UICC chief executive Cary Adams.

"Improving the collection of data is critical to our ability to address cancer around the world." IBM has turned its focus on big data, and the question of how we cope with the deluge of information, whether it be from giant telescopes such as the Square Kilometre Array or traffic congestion. Now, it will attempt to analyse cancer, creating a ­registry to guide cancer treatment policy.

Charting how Mars changed
First there was Curiosity, a mobile space laboratory sent to the red planet to wander its surface and see whether it could support life. It found, in ­summary, that Mars would be a very ­uncomfortable place for humans to live, with its freezing temperatures (about -140°C at the poles, although this can rise to 35° C at the equator during summer) and thin atmosphere.

But, once upon a time, there was water on Mars and an atmosphere that humans might have been able to survive in. This is what the United States’ National Aeronautics and Space Administration’s Maven (Mars Atmosphere and Volatile Evolution) mission aims to find out: What happened to Mars to take it from wet and warm to cold and inclement? Maven will touch down only in September next year, but it will take humans one small step closer to setting foot on the planet.