Cosmic shades reveal giant black holes

British astronomers have put on their cosmic shades to get their first good views of the biggest black holes in the universe. It was not to look cool. They managed to see through a mass of obscuring dust by fitting a giant telescope with the equivalent of Polaroid sunglasses. Supermassive black holes lurk at the centres of galaxies like our own Milky Way. Hundreds of thousands of times more powerful than ordinary black holes, they are gobbling up stars whole. Astronomers believe that these cosmic monsters, while invisible themselves because light cannot escape them, are surrounded by swirling disks of material. However, vast clouds of dust and gas at the centre of the galaxies blocked their view of the phenomenon. Now, by fitting a polarising filter to a giant, UK-run telescope on a mountain in Hawaii, they have been able to see through this barrier. The scientists say it works in the same way that polarising sunglasses cut out the glare on the surface of water to help a fisherman see beneath the surface. The breakthrough using the UK Infrared Telescope, which has a 150-inch wide mirror "eye" on the sky, is reported this week in the science journal Nature. Co-investigator on the project is my old school chum Professor Andy Lawrence, of the Institute for Astronomy in Edinburgh. He said: "For decades there has been a theory that supermassive black holes should be accumulating materials in the form of a disk, but until now this has been impossible to test due to the contamination by the dust clouds." The team hopes their cosmic sunglasses will help them to learn about the shape of the disks of matter around supermassive black holes and how they are formed. • What do you think? Skymania welcomes your comments and views. You can support this site by visiting Skymania's stores in the USA, the UK, Canada and France. They are powered by Amazon so you can buy with confidence. ©PAUL SUTHERLAND, Skymania.com

At the next lunar crater, turn left..

Space scientists are developing a new satnav system for the Moon to stop astronauts getting lost. The new global positioning system will help keep them from driving their lunar buggies to the wrong craters. It will look and operate a lot like the GPS device used by millions of motorists back home on planet Earth. But instead of using satellites, the new system will rely on photos from orbit plus a network of sensors including lunar beacons and motion detectors on the buggies themselves. It will help when manned colonies begin exploring and working on projects such as building observatories on the Moon. NASA has awarded a $1.2 million contract to scientists at Ohio State University to develop the navigation system over the next three years. The project will be led by Professor Ron Li, who is already helping two rovers, Spirit and Opportunity, to find their way around on Mars. Professor Li said that motoring on the moon was difficult because people were used to having visual clues such as buildings or other vehicles to help them judge distances. But the moon has no such cues. Getting lost, or misjudging a distant object's size and location would be easy, and extremely dangerous. He said Apollo astronauts had got within a few yards of a target crater but failed to find it because of the difficult terrain. He said: "They were so close, but they had to turn back for safety's sake." The new satnav - called the Lunar Astronaut Spatial Orientation and Information System - will be tested in the Mojave desert in California before astronauts return to the moon around 2020. Picture: The lunar buggy carried to the Moon by Apollo 15 (NASA) • What do you think? Skymania welcomes your comments and views. You can support this site by visiting Skymania's stores in the USA, the UK, Canada and France. They are powered by Amazon so you can buy with confidence. ©PAUL SUTHERLAND, Skymania.com