A plane just flew around the world using nothing but solar power

Solar Impulse 2 over San Francisco Bay. Image: Getty.

 Earlier this week, Solar Impulse 2 became the first plane in history to circumnavigate the globe using only renewable energy sources. With pilots Bertrant Piccard and André Borschberg taking turns in the cockpit, the two-tonne, 72m wingspan plane flew 42,000km, using nothing more polluting than 17,000 solar cells.

It's an incredibly achievement - but don't get too excited just yet, because it took a while. Sixteen months, to be precise.

The plane left Abu Dhabi, in the UAE, on 9 March last year, and was expected to arrive back the following August. But during the eighth of 13 planned stages - a marathon 118 hour flight across the Pacific, from Naggya, Japan to Kalaeloa, Hawaii, last June and July - it sustained damage to its batteries, and spent the next 10 months in for repairs. It completed the journey in shorter legs than originally planned, too, turning 13 stages into 17, and adding several thousand kilometres to the trip.

Even when it worked well, the trip was slow going, averaging around 76km an hour (47mph). EasyJet will not be introducing a solar powered fleet any time soon.

But the point of the exercise wasn't to set any speed records, merely to show it could be done, and to promote the potential of renewable energy. All of which it did. So, cool.

Here are some pictures of the plane on its trip around the world. They'll all expand if you click them.

Solar Impulse 2 leaves Muscat, Oman, bound for Ahmedabad, India; 10 March, 2015.


The plane flies over San Francisco's Golden Gate Bridge, on its journey from Hawaii to Silicon Valley; 23 April, 2016.


Coming into land at JFK, the plane passed the Statue of Liberty; 11 June, 2016.


Just flying over the pyramids, before coming into land on its journey from Seville, Spain, to Cairo; 11 June, 2016.


Above the Red Sea; 23 July, 2016.


Coming into land at Abu Dhabi, 16 months after it left; 26 July, 2016.


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All photos by Jean Revillard via Getty Images.



Where did London’s parakeets come from?

Parakeets in the skies above Wormwood Scrubs, west London. Image: Getty.

Visitors to London’s many green spaces would have to be stubbornly looking at their feet to not see one of the UK’s most exotic birds.  Dubbed “posh pigeons” by unimaginative Londoners, these brilliant green parakeets stand out among the fauna of Northern Europe’s mostly grey cities.

‘Parakeets’ is actually an umbrella term referring to the multiple species, which can now be found in London, Amsterdam, Brussels, Paris and various German cities. By far the most common is the Indian ring-necked parakeet, easily recognisable by the stylish red ring around their neck, a matching red beak and, of course, the loud squawking.

In the last 50 years these migrants from South Asia have arrived and thrived, settling into their own ecological niche. In the UK, London is a particular stronghold, but although they may have originally settled in the leafy streets of Twickenham, the birds can now be found in cities as far north as Glasgow.

The story of how they ended up in London is a matter of some discussion and plenty of myth. One often reported theory is that the capitals’ current population are the descendants of birds that escaped from Shepperton Studios during filming of The African Queen, starring Humphrey Bogart and Katharine Hepburn. Others would tell you that they escaped from Syon Park in the early 1970s, when a piece of debris from a passing plane damaged the aviary and allowed them to escape. This chimes with their original concentration in South West London.
My favourite story by far is that they were released by Jimi Hendrix on Carnaby Street in the late 60s. Bored of London’s grey skyline, he set the little fellas free to liven up the place.

However they got here, from 1970 onwards their numbers boomed. In 1992, 700 birds were recorded in London Bird Report. By 1998, 2,845 were seen in the London Area, and by 2006 the ring-neck parakeet was 15th most sighted bird in London.

Darwin would be proud at how well they adapted to the new environment. Toughened up by the hard Himalayan climate, they handle the cold northern European winters better than most locals. Global warming is often brought up in discussions of the parakeets, but it is certainly only part of the story.
It helps, too, that the birds have a 35 year lifespan and few local predators, enabling them to breed freely.

As with any new species, the debate has raged about whether they are harmful to the ecosystem. Strangely reminiscent of the debate over human migrants, often the birds have often been accused of stealing the homes of the natives. The parakeets do nest in tree cavities also used by jackdaws, owls and woodpeckers – but there is little evidence that native species are being muscled out. 

The also provide a food source for Britain's embattled birds of prey. Owls and peregrine falcons have been know to eat them. Charlie and Tom, two city dwelling falcons monitored by Nathalie Mahieu, often bring back parakeets as food.
Of more concern is the new arrivals’ effect on plants and trees. By 2009 their numbers in the UK had grown so much that they were added to the “general licence” of species, which can be killed without individual permission if they are causing damage.

And Parrotnet, am EU funded research project studying the development of parakeet populations across Europe, has warned of the risk they pose to agriculture. In their native India, the parakeets are known to cause widespread damage to crops. As agriculture develops in the UK in line with warmer climates, crops such as maize, grapes and sunflower will become more popular. In India the birds have been documented as reducing maize crops by 81 per cent.

So the parakeets remain divisive. Environmentalist Tony Juniper has disparagingly described them as “the grey squirrel of the skies”. By contrast, the University of York biologist Chris D. Thomas has argued that the parakeets should be left free to move and breed. He sees those wary of the parakeet boom of “irrational persecution” of the bird.

For good or ill the parakeets are here to stay. As so often with migrants of all kinds, there has been some unease about the impact they have had – but the birds, popular amongst Londoners, certainly add colour to the city. Thriving in the urban environment thousands of miles from their natural habitat, they are a metropolitan bird for Europe’s metropolitan cities. 

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