Category Archives: Nature

Antimatter caught streaming from thunderstorms on Earth

Electrons racing up electric field lines give rise to light, then particles, then light

A space telescope has accidentally spotted thunderstorms on Earth producing beams of antimatter.

Such storms have long been known to give rise to fleeting sparks of light called terrestrial gamma-ray flashes.

But results from the Fermi telescope show they also give out streams of electrons and their antimatter counterparts, positrons.

The surprise result was presented by researchers at the American Astronomical Society meeting in the US.

It deepens a mystery about terrestrial gamma-ray flashes, or TGFs – sparks of light that are estimated to occur 500 times a day in thunderstorms on Earth. They are a complex interplay of light and matter whose origin is poorly understood.

Thunderstorms are known to create tremendously high electric fields – evidenced by lightning strikes.

Electrons in storm regions are accelerated by the fields, reaching speeds near that of light and emitting high-energy light rays – gamma rays – as they are deflected by atoms and molecules they encounter.

These flashes are intense – for a thousandth of a second, they can produce as many charged particles from one flash as are passing through the entire Earth’s atmosphere from all other processes.

Scaling down

The Fermi space telescope is designed to capture gamma rays from all corners of the cosmos, and sports specific detectors for short bursts of gamma rays that both distant objects and TGFs can produce.

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I think this is one of the most exciting discoveries in the geosciences in quite a long time”

Steven CummerDuke University

„One of the great things about the Gamma-ray Burst Monitor is that it detects flashes of gamma rays all across the cosmic scale,” explained Julie McEnery, Fermi project scientist at Nasa.

„We see gamma-ray bursts, one of the most distant phenomena we know about in the Universe, we see bursts from soft gamma-ray repeaters in our galaxy, flashes of gamma rays from solar flares, our solar neighbourhood – and now we’re also seeing gamma rays from thunderstorms right here on Earth,” she told BBC News.

Since Fermi launched in mid-2008, the Gamma-ray Burst Monitor (GBM) has spotted 130 TGFs, picking up on the gamma rays in low Earth orbit as storms came within its scope.

But within that gamma-ray data lies an even more interesting result described at the meeting by Dr McEnery and her collaborators Michael Briggs of the University of Alabama Huntsville and Joseph Dwyer of the Florida Institute of Technology.

„We expected to see TGFs; they had been seen by the GBM’s predecessor,” Dr McEnery explained.

„But what absolutely intrigues us is the discovery that TGFs produce not just gamma rays but also produce positrons, the antimatter equivalent to electrons.”

When gamma rays pass near the nuclei of atoms, they can turn their energy into two particles: an electron-positron pair.

Because electrons and positrons are charged, they align along the Earth’s magnetic field lines and can travel vast distances, gathered into tightly focused beams of matter and antimatter heading in opposite directions.

The dance of light and matter continues when positrons encounter electrons again; they recombine and produce a flash of light of a precise and characteristic colour.

It is this colour of light, picked up by the Fermi’s GBM, that is a giveaway that antimatter has been produced.

The magnetic field can transport the particles vast distances before this characteristic flash, and one of the Fermi detections was from a storm that was happening completely beyond the horizon.

Gamma rays (purple) can turn into focused matter/antimatter beams (yellow)

The results will be published in the journal Geophysical Research Letters.

Steven Cummer, an atmospheric electricity researcher from Duke University in North Carolina, called the find „truly amazing”.

„I think this is one of the most exciting discoveries in the geosciences in quite a long time – the idea that any planet has thunderstorms that can create antimatter and then launch it into space in narrow beams that can be detected by orbiting spacecraft to me sounds like something straight out of science fiction,” he said.

„It has some very important implications for our understanding of lightning itself. We don’t really understand a lot of the detail about how lightning works. It’s a little bit premature to say what the implications of this are going to be going forward, but I’m very confident this is an important piece of the puzzle.”

 

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Still Looking For Paradise?

Maldives – absolutely gorgeous and the most beautiful place on earth

 

 

Double chain of twenty-six atolls…

The Republic of Maldives, or simply the Maldives, is an island nation in the Indian Ocean. It consists of approximately 1,190 coral islands grouped in a double chain of 26 atolls, along the north-south direction, spread over roughly 90,000 square kilometers, making this one of the most disparate countries in the world.

 

 

 

The atolls are composed of live coral reefs and sand bars, situated atop a submarine ridge 960 kilometers long that rises abruptly from the depths of the Indian Ocean and runs from north to south.

 

 

 

 

 

 

Crystal clear waters, beautiful white sand beaches, swaying palm trees and fabulous dive sites – that’s why the Maldives, is known for being one of the best tropical holiday destinations in the world.

 

 

 

 

 

 

 

 

 

 

 

…and no need to climb 😉

With an average ground level of 1.5 metres (4 ft 11 in) above sea level, it is the lowest country on the planet. It is also the country with the lowest highest point in the world, at 2.3 metres (7 ft 7 in). More than 80 per cent of the country’s land, composed of coral islands scattered over an area about 850 km across the equator, is less than one metre above sea level.

 

 

 

Summer never ends …

The Indian Ocean has a great effect on the climate of the country by acting as a heat buffer, absorbing, storing, and slowly releasing the tropical heat. The temperature of Maldives ranges between 24 °C (75 °F) and 33 °C (91 °F) throughout the year. Although the humidity is relatively high, the constant cool sea breezes keep the air moving and the heat mitigated.

 

 

 

Crystal clear waters and azure blue lagoons…

 

 

 

 

 

 

Resorts in the Maldives

Each resort in the Maldives is housed on a separate island by itself and offers an exotic blend of modern luxury and isolated serenity.

 

 

 

 

 

 

 

 

 

Sunny, unique and unspoiled …

 

The Mimic Octopus

Via Marginal Revolution comes this amazing video of the mimic octopus, a recently discovered chameleonic octopus which lives near Indonesia and Malaysia:


We’ve all encountered amazing examples of mimicry before – butterfly mimicry comes to mind – but, as the scientists who discovered the octopus write in their paper, the mimic octopus is unusual in its use of „dynamic mimicry”:

[D]ynamic mimicry has the unique advantage that it can be employed facultatively, with the octopus adopting a form best suited to the perceived threat at any given time.

A great example of the weirdness and intelligence of the octopus.