Closest Type Ia Supernova in decades solves a cosmic mystery

The Palomar Transient Factory caught SN 2011fe in the Pinwheel Galaxy in the vicinity of the Big Dipper on Aug. 24, 2011.

Found just hours after it exploded and only 21 million light years away, the discovery triggered the closest-ever look at a young Type Ia supernova. Credit: Image by B. J. Fulton, Las Cumbres Observatory Global Telescope Network

Type Ia supernovae (SN Ia's) are the extraordinarily bright and remarkably similar "standard candles" astronomers use to measure cosmic growth, a technique that in 1998 led to the discovery of dark energy – and 13 years later to a Nobel Prize, "for the discovery of the accelerating expansion of the universe."

The light from thousands of SN Ia's has been studied, but until now their physics – how they detonate and what the star systems that produce them actually look like before they explode – has been educated guesswork.

On August 24 of this year, searching data as it poured into DOE's National Energy Research Scientific Computing Center (NERSC) from an automated telescope on Mount Palomar in California, Peter Nugent spotted a remarkable object.

It was shortly confirmed as a Type Ia supernova in the Pinwheel Galaxy, some 21 million light-years distant. That's unusually close by cosmic standards, and the nearest SN Ia since 1986; it was subsequently given the official name SN 2011fe.

Nugent says, "We caught the supernova just 11 hours after it exploded, so soon that we were later able to calculate the actual moment of the explosion to within 20 minutes.

Our early observations confirmed some assumptions about the physics of Type Ia supernovae, and we ruled out a number of possible models. But with this close-up look, we also found things nobody had dreamed of."

"When we saw SN2011fe, I fell off my chair," says PTF team member Mansi Kasliwal of the Carnegie Institution for Science and the California Institute of Technology.

"Its brightness was too faint to be a supernova and too bright to be nova. Only follow-up observations in the next few hours revealed that this was actually an exceptionally young Type Ia supernova."

Edinburgh bright sparks solve our internet problems ... with the flick of a light switch

Edinburgh bright sparks solve our internet problems ... with the flick of a light switch - Herald Scotland

For what a world it would be if we could all access the internet not through clunky wireless routers and the millions of miles of spaghetti-like cables buried under our streets and fields, but through the golden rays of the electric light bulbs that are in every room in every one of our homes.

Scientists working at Edinburgh University have discovered a way of transmitting wireless data through lightbulbs, an invention that could revolutionise the way we receive the internet.

The discovery is called D-Light (data light) and uses the new light-emitting diode (LED) bulbs that are expected to replace the incandescent models in use. The traditional bulb is banned in parts of the EU due to its wasteful use of energy.

As well as revolutionising internet reception, it would put an end to the potentially harmful electromagnetic pollution emitted by wireless internet routers and has raised the prospect of ubiquitous wireless access, transmitted through streetlights.

The idea is so significant that a Nobel prize-winning physicist has named it among the 100 inventions likely to change everyday life in the next century.

Dr Harald Haas, reader in wireless communications at Edinburgh University, is leading the project.

He claimed the invention could soon be in use all over the world, bringing significant economic benefits to Scotland – and reaffirming the country’s position as one of the world’s leading nations when it comes to scientific innovation.

Dr Haas said: “Engineering and development have, in my opinion, been left out in this country for too long. Lord Mandelson has recently put forward his idea for the digital economy but it needs to be filled with life. This could be one pillar to that economy.

“It should be so cheap that it’s everywhere. Using the visible light spectrum, which comes for free, you can piggy-back existing wireless services on the back of lighting equipment. Power lines are there, which can transmit data, so all you need is a central modem, which would then distribute data into the lightbulbs and then to mobile devices in the home.”

The invention allows data to be transmitted through light, using flickering – imperceptible to the human eye – to send 100 megabits of data a second. That is twice as fast as current wireless routers and matches the speed of the broadband network which could get up to 100 megabits per second by 2017.

At that speed a file of an entire movie could be sent through a lightbulb in only a few minutes. But Dr Haas hopes to be able to send one gigabit a second, which is more than 10 times the speed the network can currently manage.

Wireless communication is a sector growing at an exponential rate, but the infrastructure is struggling to keep up