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Last week’s asteroid pass was the closest ever predicted. Computer graphic courtesy of NASA

Last Friday was, astronomically speaking, one of those days that comes along every 40 years.  Actually, a lot less frequently than that.  That’s how often, according to NASA estimates, an asteroid the size of the one that flew by Friday gets that close to hitting the Earth–it passed 17,000 miles away. But when you throw in the considerably smaller meteorite that exploded over Russia the same day and injured more than 1,000 people–that’s never happened before–you’re talking about one extremely unique moment in space rock history.

Most of us have moved on, taking comfort in the belief that that’s not happening again any time soon.  But there was something sobering about seeing how much damage could be done by rock about as big as one and and a half school buses. Also, that if the flyby asteroid, which was three times that size, had been on target to hit our planet, we really couldn’t have done much about it–the giant rock was spotted by a team of amateur astronomers in Spain only a year ago.

All of which prompted two basic questions: “How much warning will we get before a monster asteroid collides with the planet?” and “What’s the plan for stopping it?”

Beware of “city killers”

The good news is that NASA, which really didn’t start tracking near-Earth objects until the mid-1990s, believes it has charted almost 95 percent of the 980 asteroids more than a half-mile wide that are orbiting in our part of the universe. These are known as “planet-killers,” space rocks so large that if they collided with Earth, it would pretty much end civilization as we know it. None, I’m happy to say, are headed our way. 

But move down a bit in size to asteroids roughly between 100 feet and a half mile wide and it’s a very different story. NASA figures it’s located only 1 percent of the near-Earth objects that small. They may not sound very menacing, but keep in mind that the rock that missed us Friday was roughly 150 feet wide and it would have had a cataclysmic impact if it had exploded over or landed on a populated area. And the one that did blow apart over Russia and hurt so many people was only 55 feet wide.

Scientists at the University of Hawaii, with NASA funding, are developing a network of telescopes designed to find the smaller ones. It’s called ATLAS, which stands for the ominous-sounding Asteroid Terrestrial-Impact Last Alert System, and its creators say they’ll be able to provide a one-week warning of incoming ”city killers”–rocks about 150 wide–and three weeks notice of “county killers”–ones three times as large.

Seek and you shall find

The truth is, though, infrared telescopes surveying from space are better suited for the job, particularly when it comes to spotting asteroids orbiting close to the sun. NASA’s WISE telescope identified 130 near-Earth asteroids, but it’s been shut down for two years. Instead of replacing it, NASA is reviewing proposals for a sensor that could detect asteroids as small as 100 feet wide, while attached to a communications satellite.  

But now private groups have started floating their own ideas for finding rocks flying through space. One, called the B612 Foundation after the fantasy asteroid on which the Little Prince lived, has ambitious plans to launch a deep space telescope named Sentinel. From a vantage point as far away as Venus, it should be able to look back at our planet and see the heat signatures of objects that  come near the Earth’s orbit.  

It’s no small undertaking–the estimated cost is $450 million–but among those driving the project are two former astronauts, Russell Schweickart and Edward Lu, who’s now a Google executive and has been able to stir up interest for the mission in Silicon Valley. Lu sees last week’s double asteroid display as a wakeup call. Sure enough, his group was getting calls all day Friday from people wanting to know when it will have its telescope up. Most likely it won’t be until 2018.  

And two companies hoping to make a fortune by mining asteroids will also soon be in the business of tracking them. Planetary Resources, which includes among its investors filmmaker James Cameron, Google execs Larry Page and Eric Schmidt and X-Prize Foundation head Peter Diamandis, plans to launch its own asteroid-charting space telescope late next year. The other, Deep Space Industries, has proposed a kind of sentry line of spacecraft circling the Earth that would evaluate and, if necessary, intercept incoming asteroids. 

Taking care of business

Okay, but then what? Can an asteroid moving at 18,000 miles an hour be stopped, or at least steered away?  

Forget about the Armageddon approach. Blowing up an asteroid with a nuclear bomb–good for a movie, bad for Planet Earth. The resulting debris shower might do almost as much damage.

Instead, here are five ideas that have been proposed:  

1) A shout out to our old friend gravity: This would involve what’s referred to as a “gravity tractor.” Actually, it’s a large spaceship that would be maneuvered as close as possible to the orbiting asteroid. In theory, the gravitational pull of such a large object would be strong enough to change the asteroid’s path.  Unfortunately, some scientists say we might need a decade’s notice to pull this off.

2) Prepare for ramming speed!: The European Space Agency is working with scientists at Johns Hopkins University on a plan that would involve sending a spacecraft to bump an asteroid off course.  Called the Asteroid Impact and Deflection misson, or AIDA for short, it would actually involve sending up two spacecraft. One would be there to observe and gather data while the other does the ramming.  The goal would be to alter the asteroid’s spin and ultimately, its direction.

3) Okay, so there is a nuclear option: But it hopefully wouldn’t involve blowing up the asteroid to smithereens. Instead, scientists would prefer to detonate a device close enough that it would change the rock’s orbit.  This is always referred to as a last resort.

4) Would you like something in an eggshell? Or perhaps a tasteful pearl white?:  Then there’s the white paint strategy.  According to this plan, a spacecraft would approach the asteroid and pummel it with white paint balls.  The new white coat would more than double the rock’s reflectivity and, over time, that would, in theory, increase  solar radiation pressure enough to move it off  course. You scoff? This plan, devised by an MIT graduate student, won the 2012 Move an Asteroid Technical Paper Competition sponsored by the United Nations.

5) You knew there had to be lasers in here somewhere: And just in time for last week’s space rock event, two California scientists outlined a strategy in which they would use the sun’s power to create laser beams that could be aimed at an asteroid.  They would start small, creating an array in space about the size of the International Space Station.  The laser beams it created would be strong enough to push an asteroid on to a different path, say the plan’s inventors.  But they wouldn’t stop there.  They foresee building out the array until it’s as large as six miles wide. And then it would be able to produce laser beams powerful enough that , within a year, could vaporize an asteroid.

Sure, it sounds like a George Lucas fever dream.  But the scientists say it’s eminently feasible.  Besides, says one,  physicist Philip Lubin of  the University of California, Santa Barbara, it’s time to be proactive instead of reactive.  As he put it, “Duck and cover is not an option.”

Video bonus: In case you forgot how bad a movie Armageddon was, and that it featured Steve Buscemi as an astronaut, here’s the over-the-top trailer.

Video bonus bonus : Or if you want to stick to the real thing, here’s a collection of videos of Friday’s asteroid flyby.

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Baxter, a robot that can work with humans. Photo courtesy of Rethink Robotics

About a year ago I wrote about the first meeting of the 100 Year Starship Symposium (100YSS), a conference designed to keep scientists focused on what it will take for humans to be able to travel outside our solar system.

Luckily, they still have about a century to figure it out. NASA and DARPA, the research arm of the Defense Department, are behind the project, and the latter has kicked in $500,000 to start wrestling with the ridiculously difficult challenge of traveling trillions of miles in space by 2100.

Last week, at the second 100YSS meeting, there actually was a bit of progress to note. Along with a discussion of how many pair of underpants would be required to make such a trip and a rendition of the “Star Trek” theme song by Lt. Uhura herself, came a report that warp drive might actually be possible, that it would require far less energy than previously thought for a spaceship to travel several times faster than the speed of light.

Good news, but still a long, long way from making real something we used to see happen on TV every week. It reminded me, though, of the iterative, and often methodical process of science and how too often the focus on innovation is more about the potential of new ideas and technology and less about how they actually evolve in the real world.

So here are updates on five innovations I’ve written about in the past year. Some are already making their mark; others remain on a low boil.

1) When robots play nice: Robots work great by themselves, but mix them in with humans and it can get a little dicey. Most robots, while amazingly efficient and powerful, can also be dangerous to people nearby because, to put it simply, they don’t know we’re there.

That’s not the case, however, with a new model designed by Boston-based Rethink Robotics. It’s called Baxter and it’s been given the artificial intelligence to slow its motions when it detects a person approaching. And, to alert humans that it’s aware of their presence, its face turns red.

Next month Rethink will start selling Baxter, which can be trained by humans to do different tasks. The goal is to expand the robot market beyond big factories by providing a model that’s safe and relatively inexpensive–Baxter will cost $22,000, a steal by robot standards.

2) Replicator 2! Coming soon to an office near you!: Much has been written about 3-D printing as the future driver of manufacturing. But Bre Pettis, CEO of Brooklyn-based MakerBot Industries, has always believed in the more personal side of 3-D printers. He thinks they belong in people’s homes right next to their PCs.

Since 2009, the company has sold 13,000 of its MakerBot models. But buyers have largely been hobbyists who ordered their printers online. Now the company is taking things up a notch. Last week Pettis unveiled The Replicator 2, a sleek, stylized and more expensive model, one designed to fit right into the suitably applianced home. Also last week, MakerBot opened its first real store, in Manhattan no less.

Ah, but there’s also a bit of a dark side to giving people the power to print objects at home. Last month, a Wisconsin engineer showed readers of his blog the working gun he made.

3) Every picture tells a story. Or three: When it came on the market early this year, the Lytro camera had some people saying it would do for cameras what the iPhone did for cell phones. It made photos interactive, allowing you to change what’s in focus in an image after the fact. Chicago’s Museum of Science and Industry was impressed enough to include a Lytro in its 2012 Smart Home exhibit.

The Lytro still may transform photography, but not this year. Probably not next year, either. For now at least, most people seem perfectly content with the photos they can take on their smart phones, and they aren’t ready to pay $400 for a camera shaped like a stick of butter that allows them to do something with photos they’re not in the habit of doing.

This summer, Lytro founder Ren Ng stepped down as CEO, a move he said would allow him to focus on the company’s vision and not get bogged down in day-to-day operations. This likely has a lot to do with how quickly Lytro, which raised $50 million in private funding, has grown. It still isn’t able to fill online orders immediately–it won’t share sales figures–but Ng says it has reduced the wait time to about a month.

In case you haven’t seen how Lytro photography works, here’s a sampling.

4) Apple has spoken: A lot of attention has already been paid to the new features of the iPhone 5–its bigger screen, 4G speed, longer battery life. But it’s also worth noting something it doesn’t have–a Near-Field Communication (NFC) chip.

That’s what turns a smart phone into a mobile wallet, enabling it to make payments by waving it at checkout devices in stores. There was much speculation that if Apple gave NFC its blessing, it would push the technology mainstream in the U.S.

But Apple balked, in part because not many stores in the the U.S. have been willing to upgrade their checkout systems with NFC devices. Customers haven’t exactly been clamoring for them and besides, if Apple’s not buying in, why bother, say store owners. (Ah, the vicious circle.)

This is not good news for Isis, a partnership of mobile carriers, including Verizon and AT&T, and credit card companies, such as American Express and Capital One. The day after Apple introduced its new smart phone–minus a NFC chip–Isis announced that it was delaying the launch of its NFC mobile payments service.

5) But who’s going to blow the horn?: Since I first wrote about it in July, 2011, Google’s driverless car has received big boosts in Nevada, which last spring became the first state to issue license plates to autonomous vehicles, and California, where last month, in an extremely rare case of bipartisanship, Democrats and Republicans joined forces to overwhelmingly pass a self-driving car law. It directs the state’s Department of Motor Vehicles and the California Highway Patrol to develop safety and performance standards for robotic vehicles.

But Google’s just getting warmed up. It’s following up its success in lobbying officials there by pushing similar legislation in Florida, Arizona, Hawaii and Oklahoma. And this is a concept that’s trending: BMW and Audi are known to be working on their own versions and no less prestigious an organization as the Institute of Electrical and Electronics Engineers (IEEE) recently predicted that by 2040, 75 percent of the vehicles on the road won’t have human drivers.

Still, it’s not all open road ahead. Automakers have raised questions about their liability if they start selling driverless cars–although Google is quick to point out that its fleet of autonomous Priuses have so far logged 300,000 miles without one accident. And a consumer watchdog group in California fought the driverless car legislation, raising privacy concerns about how all the data gathered by the vehicles is used. Could you start receiving ads based on where your car drives?

Video bonus: This was probably inevitable. A candidate in Florida has come under fire for his support of driverless cars and now one of his opponent’s campaign ads features an old lady with a walker nearly run down at a stop sign by, you guessed it, a car without a driver. In case you miss the point, the large type next to her asks: “Will Driverless Cars REALLY Slow for Pedestrians?”

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Welcome to the Feel Good Future

Flying into the future. Image courtesy of the University of Miami

It’s been a month since Curiosity’s remarkable soft landing on the surface of Mars. (Video) Remember the massive, supersonic parachute that slowed the spacecraft’s descent from 1,000 down to 200 miles per hour, and the sky crane that lowered the rover on 20-foot long cables the rest of the way, touching down at a speed of under two miles per hour?

And who can forget the unnerving “Seven Minutes of Terror,” the time that would pass before NASA scientists here on Earth would know if they had pulled it off or trashed a $350 million vehicle.

Science and drama? Now that’s a special occasion.

Since then, Curiosity has shifted into research mode. It has started moving around and has sent back some stunning images, including a few in 3-D.

But, sadly, the thrills are gone. A few days ago, the big news from Mars was that Curiosity had traveled 100 feet. Or a little more than three first downs in an NFL game. Yesterday’s press release from NASA announced that the rover had extended its arm.

I know, I know, all this is being orchestrated by scientists about 60 million miles away. That is truly amazing. And this is how science is done. It’s methodical and repetitive.

But we have become a jaded bunch here on 21st century Earth and soon enough most of us will likely lose interest in reports of a machine digging in dirt, even if it is Martian dirt.

Now Curiosity is all about the science. But we’d rather have the fiction.

Submarines in space

No need to fret, though. NASA still has plenty of imagination when it comes to exploring the universe. Or at least it’s willing to put up seed money for ideas that now seem as fanciful as lowering a rover on to the surface of Mars once did. Last month, as part of its Innovative Advanced Concepts program, NASA provided funding to further study 28 different concepts with just the right touch of crazy.

Here are eight of the more intriguing ones:

1) It’s a bird, it’s a plane, it’s a wing: Flying wings aren’t new, but a star-shaped aircraft designed by a team at the University of Miami would take the concept in a new direction. Literally. Called a “Supersonic Bi-Directional Flying Wing,” it would fly sideways. It would take off in a conventional manner, then rotate 90 degrees in flight for supersonic travel. Its inventors see the wing flying from New York to Tokyo in four hours without producing a sonic boom, thanks to its unique design.

2) Sailing on Venus: Venus is one of the nastier spots in our solar system, with its average temperature of 450 degrees Centigrade and thick atmosphere of corrosive gases. But a group of NASA scientists has come up with a concept for a vehicle they say could scoot along its surface. It’s a rover powered by a sail that would take advantage of the planet’s strong winds tied to its extremely high atmospheric pressure.

3) Breaking the ice: Jupiter’s moon Europa has three times as much water as Earth, but it’s all under a thick layer of ice. That hasn’t discouraged a group of scientists at Virginia Tech who have proposed the idea of a heavy, heated torpedo that would melt the ice, then release a robotic underwater glider/submarine to explore the mysterious world beneath it.

4) Could you do that with cheese?: A big challenge to settling our moon is the need for astronauts to bring building materials with them. But a University of Southern California engineer may have developed a technology to get around that. It’s called Contour Crafting and it would allow structures to be built on the moon layer by layer using a paste made of heated-up lunar soil.

5) Pump you up: One of the risks of long space trips for astronauts is the tendency of their muscles to atrophy in zero gravity. Calves alone can lose up to 20 percent of their mass. But a scientist named Kevin Duda has created something he calls the V2 suit. It would use gyroscopes and accelerometers to track different body parts and add “viscous resistance” to mimic the sensation of gravity where it’s needed.

6) On a roll: Think tumbleweeds. That’s the basic concept behind “super ball bots,” round robots of interlocking rods and cables that would land on a planet, then be directed to roll to areas of interest. The idea is based on Buckminster Fuller’s design of round structures with no rigid connections. They’re lightweight, but amazingly stable and durable.

7) Print my ride: NASA scientists have proposed the idea of printable spacecraft--flat sheets embedded with all the electronics a robotic spacecraft needs — sensors for gathering information, data processing, data downlink and a communications system. In theory at least, multiple sheets of spacecraft could float around a planet gathering data.

8) Waste not, want not: Finally, there’s Water Walls. It’s a concept where walls filled with water would not only recycle astronauts’ waste, but would also protect them from radiation and purify the air. The walls can’t talk, at least not yet.

Video bonus: The bi-directional flying wing is so cool it comes with a soundtrack.

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What Does Space Smell Like?

Landsat image of Alaska’s Yukon Delta. Photo courtesy of NASA

For 40 years Landsat satellites have been circling the Earth, taking pictures from roughly 440 miles above us. Each loop lasts about 99 minutes and it takes about 16 days to capture the entire planet. Which means that Landsats have been recording, in 16-day intervals, the ebb and flow of our relationship with the planet since the early 1970s.

It’s been, as they say in the relationship business, a rough stretch, but for most of it, only scientists have been paying much attention. These were people tracking the explosion of cities or the scarring of rainforests or the melting of glaciers. As for the rest of us, well, we may have been aware that things were changing, and not for the better, but we had little sense of the scale or pace of change.

Now we can see for ourselves, thanks to a joint project of Google, the U.S. Geological Survey and Carnegie-Mellon University. Google has already stored 1.5 Landsat million images in its Google Earth Engine and now CMU scientists have refined software that allows many of those images to be watched as zoomable, time-lapse videos.

It’s an experience both fascinating and sobering. Take, for instance, a satellite timelapse of Las Vegas since 1999. You see the city speading like kudzu into the desert, while nearby, Lake Mead shrinks a bit more every year. The two aren’t directly related–the lake’s being drained by drought and warm winters upstream on the Colorado River. But if you live anywhere near there, it couldn’t be a comforting juxtaposition.

Or consider a time lapse of the Amazon rainforest during the same period. You watch as farmers’ fields spider out like veins from a road built through the green canopy. And when brown fields take over an area, another road is cut and more fields follow. As Carnegie Mellon scientist Randy Sargent put it, “You can continue to argue about why deforestation has happened, but you no longer will be able to argue whether it happened.”

Archaeology from space

It turns out that satellite photography isn’t just a powerful tool for tracking recent Earth events; it’s also a way to look deep into the past. A report published earlier this year revealed that archaeologists are able to see traces of now-buried ancient settlements by applying a computer program to satellite photos. This works because human settlements, specifically organic waste and decayed mud bricks, leave behind a unique signature in the soil. Under infrared analysis, it tends to be much denser than the soil around it.

Using this technique, Harvard archaeologist Jason Ur was able to spot as many as 9,000 potential hidden settlements in a 23,000-kilometer area of northeastern Syria alone. “Traditional archaeology goes straight to the biggest features — the palaces or cities — but we tend to ignore the settlements at the other end of the social spectrum,” said Ur. “The people who migrated to cities came from somewhere; we have to put these people back on the map.”

Another scientist using satellite images, Sarah Parcak, of the University of Alabama at Birmingham, actually refers to herself as a “space archaeologist.” Last year she located as many as 17 possible small pyramids buried under the sand in Egypt through a satellite survey. Said Parcak, “It’s an important tool to focus where we’re excavating. It gives us a much bigger perspective on archaeological sites. We have to think bigger and that’s what the satellites allow us to do.”

The View

Here’s a sampling of some of the more memorable images captured by satellite cameras:

• An Olympian effort: In the spirit of the Games, NASA has pulled together aerial views of the 22 cities that have hosted the Summer Olympics since the modern games began in 1896.
• Growth spurts: While we’re peering down at cities, here are 11 more that have seen explosive growth in recent decades, from Chandler, Arizona, which has eight times as many residents as it did in 1980, to the Pearl River Delta in China, which was completely rural in the 1970s and now has a population of more than 36 million.
• Scorched Earth: Only a satellite image can give you a true sense of how much devastation the Waldo Canyon fire did in Colorado earlier this summer.
• Beetle mania: More ugliness in Colorado: A satellite’s view of the destruction done by the tiny pine bark beetle.
• Breaking away: A series of satellite images captures an ice island twice the size of Manhattan breaking away from the Petermann Glacier in Greenland a few weeks ago.
• Dust never sleeps: This will make you throat go dry: A dust storm bridging the Red Sea.
• Is this place beautiful or what?: And finally…to mark Landsat’s 40th birthday, NASA and the U.S. Geological Survey asked people to vote for the Landsat image that best presented Earth as a work of art. Here are the five top choices. .

Video bonus: Check out more stunning Landsat images in this clip about how the Google Earth Engine will make it much easier for people like you and me to to follow the Earth’s transformation.

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Is mining asteroids the next space frontier? Photo courtesy of European Space Agency

A strange thing happened in Washington last week. This normally is a pretty jaded place, but when the space shuttle Discovery did its victory lap over the city atop a 747 Tuesday morning, people poured out of government buildings or raced to office windows to take one long, last look. Most fired away on their cell phone cameras, knowing that they weren’t likely to get a great shot, but equally sure they had to try.

It was a moment that revived awe, if only for fleeting minutes, one that screamed “Turning point!” in a way that history rarely does. Some, such as the Washington Post columnist Charles Krauthammer, saw it as a sad funeral procession, a “symbol of willed American decline.” Others, including America’s reigning celebrity scientist, astrophyicist Neil DeGrasse Tyson, viewed it as motivation to double NASA’s budget.

Truth is, the next chapter in American space exploration may be more likely to unfold in Seattle tomorrow when a startup called Planetary Resources has its coming-out news conference. Last week it sent out a cryptic press release, announcing that the company “will overlay two critical sectors–space exploration and natural resources–to add trillions of dollars to the global GDP.” Analysts offered an instant translation: It plans to mine asteroids.

Not a big leap to draw that conclusion, especially since one of the principals of Planetary Resources is Peter Diamandis, the space entreperneur behind the X-Prize competition, and a man who recently told an interviewer, “Ever since childhood, I wanted to do one thing–be an asteroid miner.” (The rich apparently are different from you and me.)

What makes this undertaking much more than one man tilting at asteroids, however, is the band of billionaires behind it. Drum roll, please: Film director and ocean explorer James Cameron, Google co-founder Larry Page, Google executive chairman Eric Schmidt, Google board member Ram Shriram, former Microsoft exec and two-time space tourist Charles Simonyi and Ross Perot, Jr., the suitably wealthy son of the former presidential candidate.

Obviously, it’s a group with loads of money to burn, but also one that knows something about smart investments. While mining asteroids is clearly a high-risk enterprise with enormous challenges, it has the potential to be hugely lucrative. Diamandis has estimated that the platinum alone in one relatively small asteroid could be valued as much as $20 trillion.

Still, Planetary Resources’ mission appears to be driven, at least in part, by the young-boy fantasies of very rich men. Diamandis talks of others like himself who grew up when NASA was golden and “Star Trek” aired weekly and now have the means to be space frontiersmen–people like Microsoft co-founder Paul Allen and Amazon CEO Jeff Bezos, both of whom are investing heavily in developing vehicles that can launch satellites or carry people into space.

Says Diamandis: “They’re able now to take the money they’ve made and hopefully fulfill the vision they had as a child. In our heart of hearts, many of us have given up on NASA as the mechanism to get us there.”

A rocky road

How plausible is asteroid mining? It turns out that earlier this month NASA’s Jet Propulsion Laboratory, along with the Keck Institute for Space Studies and the California Institute of Technology, released a study concluding that asteroids could be retreived, then mined. The scientists agreed that by 2025, it will be possible to have a robot spacecraft capture a 500-ton asteroid and move it into a high lunar orbit. The cost? About $2.6 billion.

But that would be for an asteroid only 22 feet or so in diameter–a big expense for a not such a big rock. And it doesn’t include the cost of actually extracting minerals. The other option would be robotic missions to asteroids where mining operations would be set up. But humans have yet to land a spacecraft on a body as small as an asteroid and take off again with minerals from the surface. The closest attempt came in 2005 when the Japan Aerospace Exploration Agency landed a probe on an asteroid. It returned to Earth five years later with about only 100 microscopic particles.

Can’t wait to see what Planetary Resources has in mind.

Meanwhile, back at NASA

No, they haven’t turned off the lights at NASA. Here’s some of its more recent news:

• Private business: The space agency has been working closely with Space Exploration Technologies, better known as Space X, in preparation for the first flight of a private spacecraft to the International Space Station at the end of April. The unmanned capsule, named Dragon, will deliver cargo after it’s grabbed with a robotic arm operated by astronauts in the space station.
• Moons over Saturn: Now 15 years into its mission, the Cassini spacecraft continues to send back images of Saturn and its moons. The most recent photos are of Enceladus and Tethys.
• Can’t get enough…of that Martian stuff: The latest rover headed to Mars, an SUV-sized vehicle named Curiosity, is now more than halfway to its destination. After it lands in early August, it will start exploring the large Gale Crater and a three-mile-high mountain inside it for signs of microbial life.
• The hunt goes on: Earlier this month NASA extended the mission of the planet-finding Kepler space telescope until 2016. It has discovered 2,300 potential alien planets since its launch three years ago.
• “Recalculating…”: NASA’s Jet Propulsion Lab in California is developing an atomic clock that will serve as a kind of GPS for spacecraft in deep space.
• Where stars are the stars: And we definitely can’t forget the Hubble Space Telescope, which turns 22 tomorrow. It just keeps delivering remarkable images from deep space, including this latest one of the Tarantula Nebula 170,000 light years away.

Video bonus: Here’s one for old time’s sake, a flashback to one of NASA’s signature moments. Using data from its Lunar Reconnaissance Orbiter, NASA has recreated what three Apollo astronauts saw on Christmas Eve, 1968 as they watched a bright blue Earth rise over the moon’s horizon.