Comet 67P/Churyumov-Gerasimenko by Rosetta’s OSIRIS narrow-angle camera. Image: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
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Rosetta becomes the first spacecraft to ever go into orbit around a comet

After a ten year chase, Rosetta became the first ever spacecraft to intercept and go into orbit around a comet - and over the next 18 months will begin searching for clues left over from the earliest moments of our Solar System.

Yesterday, after ten years of chasing, the European Space Agency’s (ESA) Rosetta spacecraft became the first ever to intercept and go into orbit around a comet. Now scientists can begin the next step in one of the most exciting investigations into how the Solar System formed that we’ve seen so far.

ESA scientists brought Rosetta to within 100km of the comet – a 3km by 5km rock called 67P Churyumov-Gerasimenko – and established a stable orbit by slowing it down with its thrusters. Perhaps surprisingly, while it’s taken ten years to get there, 67P was only discovered 50 years ago, but while not as famous a comet as Halley it’s just as scientifically interesting. Comets are considered to be primitive building blocks of the Solar System, and relics of the formation of the planets, while some even believe that they provided Earth with both water and other key ingredients too which were necessary for igniting the evolution of life. 

67P was first discovered in 1969 by Soviet astronomers Ivanovych Churyumov and Svetlana Ivanova Gerasimenko. The hope is that Rosetta will unlock the secrets of this early history – which is why it was named after the Rosetta Stone, the discovery of which in 1799 provided the key to translating Ancient Egyptian hieroglyphs and Demotic script into Ancient Greek (and thus any other language). It was launched from Europe’s spaceport in Kourou, French Guiana, in March 2004, into a long journey of loops around the Sun as it aimed to get onto the same trajectory as 67P.

Rosetta has trekked over 6bn km, passing by Earth three times, Mars once, and soaring past two asteroids, using the gravitational pull of those objects to change velocity and catch up with 67P. The riskiest part of this was when it was put into hibernation mode for 31 months to conserve power as its orbit brought it out to a distance roughly equal to the orbit of Jupiter and then back in again – where it was successfully awakened in January of this year, for the final part of the voyage.

Since May, Rosetta has performed a series of ten rendezvous manoeuvres to gradually fine-tune the spacecraft’s speed and trajectory to match those of the comet, which travels through space at speeds of up to 135,000km/h. Despite the unprecedented complexity of the mission, Rosetta’s smooth arrival was confirmed yesterday morning.

Here’s a video from the ESA showing Rosetta’s near-decade-long journey, and here’s how it’s going to orbit around 67P closer and closer:

The spacecraft now has quite the adventure to come, edging closer to the comet over the next six weeks in two triangular-shaped trajectories, first from a distance of 100km and then at 50km. Depending on the activity of the comet, it will further attempt a near-circular orbit from a distance of 30km, simultaneously scrutinising the comet’s surface for a suitable landing site for its small lander probe - Philae, named after an obelisk that was also used to decipher Egyptian hieroglyphs in the 19th century.

Philae will, sometime in November, detach from the main body of the spacecraft and anchor itself to the surface of the comet with a high-powered harpoon. Meanwhile, Rosetta will spend the next 18 months analysing the comet from every angle, retrieving crucial data enabling scientists to investigate how planets were created. The spacecraft will also accompany the comet around the Sun as it moves back out towards the orbit of Jupiter.

The mission has some similarities with Japan’s 2005 Hayabusa mission, which rendezvoused with and landed on an asteroid named Itokawa. It was meant to scoop up material from the asteroid’s surface, and return it to Earth for study – those samples arrived in 2010, but we know that its capture mechanism malfunctioned. To this day, there is some uncertainty as to whether the capsule managed to successfully collect the asteroid rock fragments.

The Rosetta mission is significantly more complex, too – while both Itokawa and 67P have miniscule gravitational pull, the former’s orbit around the Sun is relatively simple, and Hayabusa simply chased Itokawa closely around the Sun in the same orbit. Rosetta will, by reducing its speed to less than a metre per second, genuinely orbit 67P. As the comet moves towards the Sun and heats up, there are also likely to be gas and dust particles shed off into space to form its tail – and initial photographs sent to us by Rosetta, the clearest ever of a comet, do show some emissions already.

Yesterday, the elated ESA science and mission control experts celebrated the long awaited arrival, jokingly describing it as being similar to arriving at “Scientific Disneyland”. The arrival was streamed live on the ESA’s website, and Rosetta is already sending back incredible high-resolution images of the surface of 67P. So far, it looks a lot rockier and more solid than expected – less like a “dirty snowball”, and more like an asteroid.

Around the internet, there was excitement at the arrival of Rosetta. The hashtag #RosettaAreWeThereYet flooded Twitter, as people from all over the world eagerly awaited the news, like impatient school kids – even the Philae lander’s own Twitter account got involved:

But it didn’t stop there - after Rosetta finally reached its destination, even former Star Trek captain William Shatner joined the fun by engaging in playful chitchat, checking on operations with the Nasa and ESA Twitter account.

Although we know what the comet looks like from the outside, we don’t know what it looks like from the inside, and that’s what Rosetta and Philae will be uncovering over the next few months - as long as they have enough power from the craft’s huge solar panels, that is, as unlike most probes that venture out past the orbit of Mars, it has no onboard nuclear generator.

As one mission controller explained, Rosetta is going to finally “unlock the treasure chest of our own history”.

Getty.
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Forget fake news on Facebook – the real filter bubble is you

If people want to receive all their news from a single feed that reinforces their beliefs, there is little that can be done.

It’s Google that vaunts the absurdly optimistic motto “Don’t be evil”, but there are others of Silicon Valley’s techno-nabobs who have equally high-flown moral agendas. Step forward, Mark Zuckerberg of Facebook, who responded this week to the brouhaha surrounding his social media platform’s influence on the US presidential election thus: “We are all blessed to have the ability to make the world better, and we have the responsibility to do it. Let’s go work even harder.”

To which the only possible response – if you’re me – is: “No we aren’t, no we don’t, and I’m going back to my flowery bed to cultivate my garden of inanition.” I mean, where does this guy get off? It’s estimated that a single message from Facebook caused about 340,000 extra voters to pitch up at the polls for the 2010 US congressional elections – while the tech giant actually performed an “experiment”: showing either positive or negative news stories to hundreds of thousands of their members, and so rendering them happier or sadder.

In the past, Facebook employees curating the site’s “trending news” section were apparently told to squash stories that right-wingers might “like”, but in the run-up to the US election the brakes came off and all sorts of fraudulent clickbait was fed to the denizens of the virtual underworld, much – but not all of it – generated by spurious alt-right “news sites”.

Why? Because Facebook doesn’t view itself as a conventional news provider and has no rubric for fact-checking its news content: it can take up to 13 hours for stories about Hillary Clinton eating babies barbecued for her by Barack Obama to be taken down – and in that time Christ knows how many people will have not only given them credence, but also liked or shared them, so passing on the contagion. The result has been something digital analysts describe as a “filter bubble”, a sort of virtual helmet that drops down over your head and ensures that you receive only the sort of news you’re already fit to be imprinted with. Back in the days when everyone read the print edition of the New York Times this sort of manipulation was, it is argued, quite impossible; after all, the US media historically made a fetish of fact-checking, an editorial process that is pretty much unknown in our own press. Why, I’ve published short stories in American magazines and newspapers and had fact-checkers call me up to confirm the veracity of my flights of fancy. No, really.

In psychology, the process by which any given individual colludes in the creation of a personalised “filter bubble” is known as confirmation bias: we’re more inclined to believe the sort of things that validate what we want to believe – and by extension, surely, these are likely to be the sorts of beliefs we want to share with others. It seems to me that the big social media sites, while perhaps blowing up more and bigger filter bubbles, can scarcely be blamed for the confirmation bias. Nor – as yet – have they wreaked the sort of destruction on the world that has burst from the filter bubble known as “Western civilisation” – one that was blown into being by the New York Times, the BBC and all sorts of highly respected media outlets over many decades.

Societies that are both dominant and in the ascendant always imagine their belief systems and the values they enshrine are the best ones. You have only to switch on the radio and hear our politicians blithering on about how they’re going to get both bloodthirsty sides in the Syrian Civil War to behave like pacifist vegetarians in order to see the confirmation bias hard at work.

The Western belief – which has its roots in imperialism, but has bodied forth in the form of liberal humanism – that all is for the best in the world best described by the New York Times’s fact-checkers, is also a sort of filter bubble, haloing almost all of us in its shiny and translucent truth.

Religion? Obviously a good-news feed that many billions of the credulous rely on entirely. Science? Possibly the biggest filter bubble there is in the universe, and one that – if you believe Stephen Hawking – has been inflating since shortly before the Big Bang. After all, any scientific theory is just that: a series of observable (and potentially repeatable) regularities, a bubble of consistency we wander around in, perfectly at ease despite its obvious vulnerability to those little pricks, the unforeseen and the contingent. Let’s face it, what lies behind most people’s beliefs is not facts, but prejudices, and all this carping about algorithms is really the howling of a liberal elite whose own filter bubble has indeed been popped.

A television producer I know once joked that she was considering pitching a reality show to the networks to be called Daily Mail Hate Island. The conceit was that a group of ordinary Britons would be marooned on a desert island where the only news they’d have of the outside world would come in the form of the Daily Mail; viewers would find themselves riveted by watching these benighted folk descend into the barbarism of bigotry as they absorbed ever more factitious twaddle. But as I pointed out to this media innovator, we’re already marooned on Daily Mail Hate Island: it’s called Britain.

If people want to receive all their news from a single feed that constantly and consistently reinforces their beliefs, what are you going to do about it? The current argument is that Facebook’s algorithms reinforce political polarisation, but does anyone really believe better editing on the site will return our troubled present to some prelap­sarian past, let alone carry us forward into a brave new factual future? No, we’re all condemned to collude in the inflation of our own filter bubbles unless we actively seek to challenge every piece of received information, theory, or opinion. And what an exhausting business that would be . . . without the internet.

Will Self is an author and journalist. His books include Umbrella, Shark, The Book of Dave and The Butt. He writes the Madness of Crowds and Real Meals columns for the New Statesman.

This article first appeared in the 24 November 2016 issue of the New Statesman, Blair: out of exile