Black holes are collapsed stars with a gravitational pull such that nothing – not even light – can escape once a certain threshold, known as the event horizon, has been passed. They can only be observed indirectly by the swirling matter around them, and they are thought to emit an extremely weak flow of particles and photons called the Hawking radiation. Now some of these black holes are thought to be wormholes, gateways to other universes.

Two physicists from France and Germany are studying the possibility to distinguish both astrophysical anomalies despite the technical difficulties that currently prevent them from doing so. They have theorized that the detection of both Hawking radiation and an event horizon would identify the object as a black hole, whereas the absence of both would classify it as a wormhole.

Future particle accelerator experiments should enable scientists to create microscopic black holes and test this theory. If small-size wormholes can be produced, we may see one day the fiction of Stargate become a reality. This could also revolutionize long-distance travel, like in Stephen King’s short story “The Jaunt.”

Source: New Scientist

Gliese 581 is a red dwarf – smaller and colder than our Sun – which is ‘only’ just over 20 light years from here and scientists just found an Earth-like planet orbiting around it. It is 1.5 times the size of our home world, rocky and, with temperatures between 0°C and 40°C, very likely to have liquid water on its surface. Where there is water, there is also very often life too, and the search has started to determine if living organisms are to be expected on Gliese 581 c, as this big “Earth II” is known.

The planet is of course too far to send an exploration ship in the near future, and we’ll need to develop an appropriate technology that will enable humans to go and visit it one day. In the meantime, radio waves from Earth dating from the mid-eighties have just reached it, making us somehow hope that there isn’t any advanced civilisation listening – with Culture Club and Spandau Ballet, what must they think of us!?

Astronomers have discovered the most Earth-like planet outside our Solar System to date, an exoplanet with a radius only 50% larger than the Earth and capable of having liquid water.

Source: ESO

Planets form around a star from what is known as an accretion disk, made of gas and dust. These younger, cooler stars are however in danger of having their nascent planets boiled off if they happen to be too close – less than about 1.6 light-years – to an older, hotter star. These new findings from a team using NASA’s Spitzer Space Telescope will allow scientist to determine which stars are more likely to have a planetary system with rocky planets such as Earth and refine the search for extra-terrestrial life.

Astronomers have laid down the cosmic equivalent of yellow “caution” tape around super hot stars, marking the zones where cooler stars are in danger of having their developing planets blasted away.

Source: PhysOrg.com

Whereas the astronauts of the space Shuttle missions or the International Space Station (ISS) are protected by the Earth’s magnetic field, ships embarking for further long-term expeditions may be at risk from solar winds and other particles from outer space. A team of scientists at the Rutherford Appleton Laboratory near Oxford, UK, is currently working on the possibility to use a bubble of charged particles – known as plasma – as a protective shield, in parallel to the research conducted at the University of Washington in Seattle, USA.

The aim of this work is to build a device able to produce enough plasma around the spacecraft – contained by a magnetic field – to prevent potentially harmful external particles from reaching the ship. It may take another few years to develop this technology, but the deflector shields of Star Trek’s USS Enterprise will most probably become a reality one day.

Magnetic “deflector shields” could one day guard astronauts against dangerous space radiation, if experiments now underway pay off.

Source: New Scientist

One of NASA’s most complex measurement satellites has confirmed that Einstein was right all along: massive objects do distort the fabric of time and space. This ‘geodetic’ effect may only be part of Einstein’s Theory of Relativity, but these results confirm a significant chunk of what the genius had hypothesized some 90 years ago. The rest of the theory – namely the ‘frame-dragging effect’ – will take another few months to be tested by the probe.

Could this be the first step towards designing a ‘gravity drive’ such as the one that allowed a ship to travel through space and time in the 1997 movie Event Horizon? Let’s hope that such a spacecraft will have a better fate than the Hollywood one!

Ninety years after he expounded his famous theory, a $700m Nasa probe has proved that the universe behaves as he said. Now the race is on to show that the other half of relativity also works.

Source: The Observer