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Aussie Telescope Almost Doubles Known Number of Fast Radio Bursts

By David Reneke

The number of known fast radio bursts has doubled, and a patent has brought a space elevator one step closer.

Australian researchers using a CSIRO radio telescope in Western Australia have nearly doubled the known number of mysterious fast radio bursts – powerful flashes of radio waves from deep space. The team’s discoveries include the closest and brightest fast radio bursts ever detected.

Fast radio bursts come from all over the sky, and last for just milliseconds. Scientists don’t know what causes them but it must involve energy equivalent to the amount released by the Sun in 80 years.

“We’ve found 20 fast radio bursts in a year, almost doubling the number detected worldwide since they were discovered in 2007,” said Dr Ryan Shannon of Swinburne University of Technology and the OzGrav ARC Centre of Excellence. Using the Australia Square Kilometre Array Pathfinder (ASKAP), his team also proved that fast radio bursts are coming from the other side of the universe rather than from our own galactic neighbourhood.

Collaborator Dr Jean-Pierre Macquart of the Curtin University node of the International Centre for Radio Astronomy Research said bursts travel for billions of years and occasionally pass through clouds of gas. Eventually the burst reaches Earth, with its spread of wavelengths arriving at the telescope at slightly different times.

Because this study has shown that fast radio bursts come from far away, scientists can now use them to detect all the missing matter located in the space between galaxies. Shannon said we now know that fast radio bursts originate from about halfway across the universe, but we still don’t know exactly what causes them or which galaxies they come from.

The team’s next challenge is to pinpoint the locations of bursts in the sky. “We’ll be able to localise them to better than a thousandth of a degree,” Shannon said. “That’s about the width of a human hair seen 10 metres away, and good enough to tie each burst to a particular galaxy.”

ASKAP is located at CSIRO’s Murchison Radio-astronomy Observatory in Western Australia, and is a precursor for the future Square Kilometre Array telescope.

Chinese Scientists Get Ready to Build a Space Elevator

Chinese scientists at Tsinghua University have patented a carbon nanotube fibre they say is strong enough to build a space elevator. They say the fibre will be in great demand in many high-end fields such as sports equipment, ballistic armour and aeronautics – and would be perfect for space elevators.

Is a lift that could travel from the Earth into space actually possible, or is it just the stuff of science fiction? Although generations of research have made the rocket the most reliable form of propulsion ever invented, space vehicles are still grossly inefficient.

The appeal of a space elevator relies on finding a much cheaper way to travel to space. It costs more than US$160 million to launch a satellite for a single trip, but it is estimated that a space elevator could reduce that to less than US$2 million per person per trip.

The basic concept of a space elevator involves a cable anchored to the Earth’s surface and attached to a counterweight that is sent into orbit. If the cable is long enough, say 36,000 km or three times the Earth’s diameter, it will be pulled taut and upright by gravity and centrifugal force. A vehicle simply travels along the cable, propelled by the Earth’s rotational energy.

Japan recently launched two satellites in the first experiment to study elevator movement in space involving a mini-lift travelling along a cable from one satellite to another. The results are encouraging. China has also carried out earlier space tethering tests, but to date have not revealed the details.

David Reneke is an astronomy lecturer, writer and broadcaster (