With the US shuttle Atlantis landing back on Earth, the spotlight of the space-facing world has been firmly fixed on the end of the 30-year US space shuttle programme. What many forget is that there is more going on in space than the experiments on the International Space Station (ISS), other missions that may reveal far more valuable information than the shuttles or the ISS ever could. The Dawn space probe, launched nearly four years ago, has finally reached one of its destinationsa huge asteroid called Vesta in the asteroid belt between Mars and Jupiter, around 5 billion kilometres away. Why is this important Because Vesta and its sibling asteroids are believed to be intact remnants of planetary formation that took place 4.5 billion years ago. Studying them could provide valuable insights into what the solar system was like as it was being born. Vesta, about 500 kilometres in diameter, is the brightest asteroid in the sky, and is only one of two targets that Dawn is supposed to reach. Six months and several thousand photographs later, Dawn will leave Vesta on its way to another, much larger, asteroid, Ceres. Ceres, at around 950 kilometres in diameter, is so huge that scientists have classified it as a dwarf planet. If it wasnt for the disrupting effect of Jupiters gravity, Ceres could have coalesced with other smaller asteroids and become a full fledged planet itself. As it is, the several instruments on Dawn are expected to find a treasure trove of information on the early days of the solar system on it.
A heightened sense
In the face of the vast distances in space, measurements on Earth seem to pale in comparison. But still, the 8,848 meters (29,029 feet) height of Mount Everest is a breathtaking figure. And its set for a revision, in all probability upwards of its current figure. The back story is that China and Nepal, where the mountain is located, have been involved in a long dispute over the precise height of the highest mountain in the world. The Chinese felt that the mountains height should be measured in terms of its rock height, whereas the Nepali government felt that it should be measured according to its snow height, a mere four metre difference. The broadly-accepted height of 8,848 meters was first recorded by Indians in 1955. But geologists believe that this figure has changed over time, with the shifting continental plates gradually pushing India under China and Nepal, raising the mountain range in the process. In May 1999, an American team used GPS technology to peg Mount Everests height at 8,850 meters, a figure that is now used by the US National Geographic Society. Nepal, however, has not accepted this figure and has initiated its own measure of the height of the mountain to end the debate once and for all.