NASA lands nuclear-powered, laser-armed, one-tonne rover on Mars

The Curiosity rover has been travelling for 10 months and made a safe touchdown this morning.

At 6:30am BST, NASA's Curiosity rover touched down on Mars, making it the seventh successful attempt to land a man-made object on the planet, and the largest such object yet.

Following its launch from Cape Canaveral in November last year, the mission has covered the 563 million kilometer distance without concern, but the most dangerous aspect of the trip was always going to be the last seven minutes of the descent to Mars. The Martian atmosphere is thin enough that it isn't capable of slowing objects travelling at interplanetary velocity down enough for them to make a safe landing, while being thick enough that the friction is capable of doing serious damage to an unprotected craft.

Once the rover hit the atmosphere, it had to execute a complicated series of manouvers, first deploying a massive parachute, then rocket thrusters, and then, at the very end, hovering just above the surface and lowering the car-sized rover down on nylon strings. And it had to do all of this without any aid from the control room on Earth, due to the 14 minutes it takes for radio signals from Mars to reach earth. So by the time we heard that the rover had hit the atmosphere, it had actually been sitting on the planet – dead or alive – for seven minutes.

NASA's video explaining the "seven minutes of terror" – unfortunately officially called "EDL", for "entry, descending, landing" – conveys the sheer scale of the challenge:

Now that it has arrived, the rover's first task is to explore Gale crater, its landing site. The crater contains a number of interesting geological features, including what appears to be a 5km high mountain formed out of sedimentary rock, which would make it one of the largest artifacts of running water on Mars.

But that preliminary mission is unlikely to be the rover's only one. NASA's increasingly successful missions to send rovers to Mars have been typified by the flexibility which the mobile design offers. The Pathfinder mission, which deposited a lander (a stationary craft) and a rover (named Sojourner) on Mars in 1997, was intended to last a week to a month, but ended up returning usable data for three. The follow-up rovers, Spirit and Opportunity, landed in 2004 with 90 days of planned experiments. Spirit eventually got stuck in late 2009 and stopped sending signals back to Earth in 2010, while its twin Opportunity is still active, 3,026 days after its mission was supposed to end.

But Curiosity is a different scale of mission – literally. While Sojourner was 65cm long and weighed 10.5kg, and Spirit and Opportunity 1.6m and 180kg, Curiosity is over 3m long and weighs almost a tonne. Rather than being powered by solar panels, which runs the risk of outages during dust storms and the Martian night, it contains a plutonium battery, which generates heat to be turned into electricity. It also has a laser which can burn holes in rocks from up to 7 meters away, in case of attack to analyse the chemical composition of the planet, and sensors which detect visible light, x-rays, neutrons and ultraviolet radiation, all for science. In essence, NASA has landed a nuclear power, laser-armed SUV on Mars for one fifth the cost of the Olympics. Oh, and it tweets.


The Mars rover family. Pictured, clockwise from bottom left: models of Sojourner, Spirit/Opportunity, two human males, and Curiosity. Photograph: NASA

Alex Hern is a technology reporter for the Guardian. He was formerly staff writer at the New Statesman. You should follow Alex on Twitter.

Show Hide image

Why the philosophy of people-rating app Peeple is fundamentally flawed

The app claims that “character is destiny”, and that we should be constantly judged based on our past interactions with others. But do we really believe that? 

Yesterday, you were probably one of the millions around the world who recoiled from their screen in blank-eyed horror at the news: Peeple, an app to be launched in November, will let others rate you, publicly, on the internet, and there's nothing you can do about it. You can't opt out, and you don't need to join in order to be rated on a scale of one to five by colleagues, friends, and romantic partners. That boy whose girlfriend you stole? He can review you. The boss you swore at as you quit? Her, too. Those people in your life who think you're just a bit average? Expect a lukewarm three stars from them.

Of all the online rage at the app's announcement, perhaps the most was directed at the fact that you can't remove your own profile. Other users need only submit your mobile number and name to create your page, and you have no control about who posts on there. Reviews of two stars or less are invisible to the public for 48 hours, and you have the chance to review them and try to "work it out" with the rater. Once that time is up, though, the negative reviews appear for all to see. You can comment on them to defend your corner, but unless they break the app's rules, you can't delete them.

There are all kinds of problems with Peeple's premise. Despite its founders' promises that bullying and harassment won't be tolerated (helped slightly by the fact that users must be over 21 and use their full name and Facebook profile to comment), it seems impossible that they'll be able to moderate this effectively. And as we've learned from sites like TripAdvisor or Yelp, the majority of reviews are from those seeking to boost the company's reputation, rivals, or angry customers - it's rare to see one that's balanced and helpful.

Yet the biggest flaw of all is the assumption that public rating and shaming has a place, or is even acceptable, in our society. There's something fundamentally broken in the app's presmise, which is summarised in its tagline, "character is destiny".  As western society has moved on from earlier ages where people were fundamentally changed in the eyes of the law and public into "criminals" by virtue of their deeds, or a time where a woman was utterly defined by her sexual acts, we've ceased to accept this as truth. The app's whole set-up assumes that someone who has offended a co-worker is likely to do it again, or a positive review from a partner makes it likely you'll enjoy a good relationship with them. As a society, we accept that some violent criminals are likely to re-offend, but we also see the value of rehabilitation, and can accept that people make mistakes they're unlikely to repeat. 

The dark side of social media is that it moves us backwards on this front. It allows permanent imprints of our online lives to be seen by everyone, to the extent where they seem to represent us. Victims of cyberbullying terrified that naked photos of them will be released, or people who make public gaffes on social media, become reduced to and defined by single acts. The mental health deterioration (and sometimes  suicide) that follows these shamings hints at how unnatural it is for single actions to change lives in such disproportionate ways. 

Jon Ronson, author of So you've been publicly shamed, which cleverly links the current culture of internet shaming with a legal past where criminals were shamed indefinitely as criminals for a single illegal act, seems chilled by the prospect of Peeple:

As one review of Ronson's book noted:

As Ronson makes patently clear, all these people’s punishments by far outweighed the gravity of their so-called crimes. In fact, having researched the history of public shaming in America in the Massachusetts Archives, he can only conclude that Lehrer, for one, was humiliated to a degree that would have been thought excessive even in the 18th century, the Puritans of New England having seemingly worked out that to ruin a person in front of his fellows is also to refuse him a second chance in life.

As Ronson explores in his book, extreme public shaming doesn't make us better people, or encourage us not to repeat offend: it shuts us down and exiles us from society in a way that benefits no one. (This makes Peeple's URL – – seem grimly ironic). What Ronson calls "chronic shame" occurs when our regretted actions harden into something far greater, something we allow to become part of ourselves. As Gershen Kaufman, a scholar of shame, notes:  "Shame is the most disturbing experience individuals ever have about themselves; no other emotion feels more deeply disturbing because in the moment of shame the self feels wounded from within."

We also shouldn't be forever defined by a clutch of "good" actions, or people who see some benefit in leaving us gushing reviews. Those who measure their worth through social media come to rely on the endorphins sparked by small online interactions and boosts to their confidence, at the expense of the more slow-burning satisfaction of real life. A single person's thoughts about us are relatively inconsequential, whether positive or negative - but they're given far greater weight on the internet  by virtue of their permanence and publicity.

In Mary Gordon's novella The Rest of Life, a character wishes that someone had told her earlier that "the world is large and will absorb the errors you innocently make". If we're to avoid tearing each other to pieces, we need to make sure that this remains the case. 

Barbara Speed is a technology and digital culture writer at the New Statesman and a staff writer at CityMetric.