TIME astronomy

NASA’s Kepler Telescope Discovers Another Planet on Comeback

The discovery marks a remarkable turnaround for Kepler

NASA’s Kepler spacecraft has found another new planet.

Dubbed HIP 116454b, the new body is bigger than Earth, smaller than Neptune and probably too hot to sustain life as we know it.

“The Kepler mission showed us that planets larger in size than Earth and smaller than Neptune are common in the galaxy, yet they are absent in our solar system,” Steve Howell, a project scientist at NASA’s Ames Research Center in California, said in statement.

The discovery marks a remarkable turnaround for Kepler. In May 2013, one of Kepler’s stabilizing reaction wheels failed and a team of engineers and scientists were forced to fashion an ingenious alternative for controlling the spacecraft, using pressure generated from sunlight.

During a subsequent test run in February, Kepler collected data on a previously undiscovered planet 180 light-years from Earth.

Follow-up observations confirmed the existence of the planet, which astronomers have called a watery “mini-Neptune,” with a tiny core and gaseous atmosphere, reports the New York Times.

TIME Behind the Photos

Go Behind TIME’s NASA Cover with Photographer Marco Grob

NASA astronauts and twin brothers Mark and Scott Kelly are on the cover of TIME

TIME contract photographer Marco Grob’s first memory was of the Moon landing. “Anything that’s space-related is very special for me,” he says. So when TIME asked him to photograph Mark and Scott Kelly, NASA’s famous twin brothers, he jumped on the opportunity, traveling to the Johnson Space Center in Houston, Texas.

“In a weird way, being at NASA and having such access felt too good to be true for a guy like me. It’s one of the most memorable shoots I’ve done,” he says. “Both of them, by all means, are very extraordinary men.”

Grob used a simple lighting setup to photograph the twin brothers. “I wanted the textures to stand out on their own, especially with the space suit. I wanted a lighting that served the purpose instead of overpowering the image.”

The photographer also wanted to highlight the extraordinary nature of his subjects. “People don’t always understand how enormously difficult it is to become an astronaut,” he says. “So to have a family where you have two twin brothers that are astronauts, it’s just tremendous. So I felt that showing them next to each other, without any distraction, would be a really big deal. I like the simplicity of that photo.”

Given Grob’s love of space, it’s no surprise that these portraits of Mark and Scott Kelly will remain among his favorites — yet the photographer was surprised by one thing: how welcoming NASA was. “For them, it was a big deal to have a TIME cover,” he says. “So it’s pretty cool when you go to NASA and they are the ones that think it’s a big deal. Normally, it’s the other way around.”

Marco Grob is a TIME contract photographer.

Olivier Laurent is the editor of TIME LightBox. Follow him on Twitter and Instagram @olivierclaurent

TIME space

Voyager 1 Surfs a Cosmic Tsunami

Wow, Voyager: 12 billion miles from home and still very much in the game
Wow, Voyager: 12 billion miles from home and still very much in the game NASA/JPL

Earth's only Interstellar spacecraft is rocked by a storm from the sun

Planetary scientists have pretty much stopped haggling over whether Voyager 1, the space probe launched in 1977 to explore Jupiter and Saturn, has finally entered interstellar space. The tough little ship is still going strong, but there isn’t exactly a signpost that marks the heliopause—the place where particles streaming from the Sun bang into the thin gas that lies between the stars. As a result, there’s been some confusion about when the spacecraft actually crossed that invisible boundary—though there’s no confusion over the fact that it did. (There’s no confusion either about whether it’s left the Solar System: despite last year’s breathless headlines, it hasn’t. Comets in the Oort Cloud, which are definitely under the Sun’s gravitational influence, are much farther out than the heliopause.)

But the fact that Voyager 1 is now firmly in interstellar space is evident just by the change in its surroundings, says Don Gurnett, of the University of Iowa, whose plasma wave instrument aboard the probe is the final arbiter. “It’s extremely quiet out there,” Gurnett says. “The magnetic fields are constant, the flux of cosmic rays is constant”—a sharp contrast to the turmoil of the so-called termination shock, where particles racing outward at a million m.p.h. (1.6 million k/h) slam into the relatively stationary particles that make up the interstellar medium.

But the comparative quiet of distant space does not mean there’s nothing going on out there. At this very moment, in fact, as Gurnett explained at a talk at the American Geophysical Union’s annual meeting in San Francisco this week, the sparse interstellar gas is reeling from a powerful blast of solar particles that smashed into it last February. The eruption began its life as a coronal mass ejection or CME, a huge burst of hot plasma fired into space during a solar storm. When they hit the Earth, CMEs can disrupt electronic communications and even cause blackouts.

Their impact further away is much greater, causing a kind of cosmic tsunami—huge pressure waves that make the interstellar gas vibrate like a ringing bell. Indeed, a recording the spacecraft made and NASA released reveals that the phenomenon even sounds like a bell. “This shows us how much influence the Sun can have on the surrounding area,” says Caltech physicist Ed Stone, who has been the Voyager project scientist since 1972, “and it’s very likely to be the same with other stars.”

Voyager detected its first cosmic tsunami back in the 1990’s when the impact of a CME colliding with the heliopause created a blast of radio waves. They’re too faint to be picked up from Earth, says Stone. “You need to be out by Saturn, at least, to detect them.” By 2012, the spacecraft was close enough to the heliopause to experience a later tsunami directly, recording a steep increase in the density of the gas it was flying through. It felt another in 2013, and the probe is now in the midst of its third, which was still going nine months later—a period during which Voyager 1 traveled a quarter of a billion miles (.4 billion km). No one knows how far into space the tsunami will travel before it fades out, says Gurnett. “I’m guessing it could be another hundred astronomical units or more.”

That, by the way, is a whole lot. An astronomical unit is the equivalent of the distance between the Earth and the sun—or 93 million mi. (150 million km). A hundred of those is 9.3 billion miles—or 15 billion km. Voyager 1 is currently at 130 A.U., or about 12 billion miles; it will have to reach 21.3 billion just to catch up with the outer reach of the tsunami—a journey that will take decades.

Stone, Gurnett and the other Voyager scientists won’t have to wait that long for another big event, however. The Voyager 2 probe, which lagged behind its sister ship so it could take a look at Uranus and Neptune, is currently at 109 A.U. from the Sun, and approaching its own rendezvous with the heliopause. “We’re hoping it will happen in the next couple of years,” says Stone.

If it’s hard to imagine what it’s like for Stone to watch the Voyager probes continue to make discoveries more than four decades after he took over the project, he offers a single, simple word of explanation: “Wonderful.”

TIME space

NASA Can See Holiday Lights From Space

NASA Holiday Lights
City lights shine brighter during the holidays in the U.S. when compared with the rest of the year, as shown using a new analysis of daily data from the NASA-NOAA Suomi NPP satellite. Dark green pixels are areas where lights are 50 percent brighter, or more, during December. NASA's Earth Observatory/Jesse Allen

Cities are brighter during the holidays than any other time in the year

The holiday lights on your roof are so bright they’re visible from space.

NASA said Tuesday that data from a polar-orbiting satellite, in partnership with National Oceanic and Atmospheric Association, shows how cities’ nighttime lights change during the holiday season. From Black Friday until New Year’s, city lights are about 20 to 50% brighter than other times of the year.

“It’s a near ubiquitous signal. Despite being ethnically and religiously diverse, we found that the U.S. experiences a holiday increase that is present across most urban communities,” said Miguel Román, a research physical scientists at NASA Goddard who co-led the research. “These lighting patterns are tracking a national shared tradition.”

Researchers also took a look at holiday lights during the holy month of Ramadan in the Middle East, where nighttime lights shine up to 50% brighter. Scientists discovered some cities were lit more heavily throughout the region, which they attributed to political or cultural differences.

“Even within majority Muslim populations, there are a lot of variations,” said Eleanor Stokes, a graduate fellow at NASA. “What we’ve seen is that these lighting patterns track cultural variation within the Middle East.”

TIME space

Odds For Life on Mars Tick Up—a Little

High-tide: layering in a Mars rock photographed by Curiosity suggests the movement of long-ago water
High-tide: layering in a Mars rock photographed by Curiosity suggests the movement of long-ago water NASA/JPL

New findings about both methane and water boost the chances for biology

September of 2013 was a bad time for those who hope there’s life on Mars. We’ve had evidence for decades that water flowed freely across the surface of the Red Planet billions of years ago, and that evidence has only gotten stronger and stronger the closer we look. Not only was there potentially life-giving water back then: Mars also had the right kind of geology to support mineral-eating microbes. And while all of that was in the distant past, the detection of methane in the Martian atmosphere by Earth-based telescopes and Mars orbiters raised hopes that bacteria might still be thriving below the surface—not unreasonable, both because all manner of Earthly critters do perfectly well below-ground and because the vast majority of methane in our own atmosphere results from biological activity. Mars’s methane might come from a similar source.

But when the Curiosity rover sniffed the Martian air directly last year, it smelled…nothing. At most, there were just three parts per billion (ppb) of methane wafting around, and possibly much less than that. “We kind of thought we’d closed that chapter,” says Christopher Webster of the Jet Propulsion Laboratory, lead scientist for the instrument that did the sniffing. “A lot of people were very disappointed.”

Not any more, though. Just weeks after that dismal reading, Curiosity’s Tunable Laser Spectrometer (TLS) picked up a whiff of methane at a concentration of 5.5 parts per billion. “It took us by surprise,” says Webster, and over the next two months, he says, “every time we looked there was methane. Indeed, the concentrations even rose, to an average of 7.2 ppb over that period, he and his colleagues report in a new paper in Science.

And then, six weeks later, the methane was gone, and hasn’t been sniffed since. “It’s a fascinating episodic increase,” Webster says.

What he and his colleagues can’t say is where the methane is coming from. Because it’s transient, they think it’s probably from a fairly local source. But whether it’s biological or geological in origin, they don’t know. It’s wise to be cautious, however, says Christopher Chyba, a professor of astrophysics and international affairs at Princeton. “Hopes for biology on Mars have had a way of disappearing once Martian chemistry has been better understood. But figuring out what’s responsible for the methane is clearly a key astrobiological objective—whatever the answer turns out to be.”

That’s not the only important Mars-related paper in Science this week, either. Another, also based on Curiosity observations, concerns Mars’s long-lost surface water, and one of the most important points is that there’s a lot more of it left than most people realize—”enough,” says Jet Propulsion Laboratory scientist Paul Mahaffy, lead author of the paper, “to cover the surface to a depth of 50 meters [about 165 ft].” That doesn’t mean it’s accessible: it’s nearly all locked up in ice at the planet’s poles, but some is also entrained in the clay Curiosity dug into when it was prowling the Yellowknife Bay area of Gale Crater.

Some of that water, says Mahaffy, is tightly chemically bound to the clay and is not a big player in Mars’s modern environment. Some is not quite so locked down and has been interacting with the tenuous Martian atmosphere for the past three billion years. The hydrogen in Martian water, as in Earthly water, may contain both a single proton and a single electron, or a proton and electron plus a neutron—so-called heavy hydrogen, or deuterium. As the Martian atmosphere has thinned over the eons, the ratio of hydrogen to deuterium in the water has gradually been dropping, as the lighter version escapes more easily into space. Since the modern water is twice as rich in deuterium as the water from billions of years ago, that suggests that there was about twice as much surface water in total at the earlier time, but its hydrogen residue has vanished.

“That’s a fair bit of water,” says Mahaffy, “but it’s a lower limit. There could be much more beneath the surface today that we haven’t seen. It was a really interesting time. There were a lot of aqueous processes going on, and a lot of flowing water.”

Where there is (or was) water, there could be (or could have been) life. For Mars enthusiasts, that’s why December of 2014 is a lot better than September of 2013.

TIME Science

Apollo 17 and the Case for Returning to the Moon

Harrison H. Schmitt on moon
Apollo 17 astronaut Jack Schmitt standing on surface of moon while holding a rake full of rock samples, with Rover in distance Time Life Pictures / Getty Images

It's been two generations since the moon was eclipsed in NASA's priorities

Richard Nixon was a lunar buzzkill—but at least he was honest about it. During the early years of the space program, Nixon held no political office, which put him on the sidelines for all of the one-man Mercury flights and two-man Gemini flights, as well as the first two flights of the Apollo program. But he assumed the presidency in January of 1969 and was thus the one who got to spike the football in July of that year, phoning the moon from the Oval Office to congratulate the Apollo 11 crew on their historic lunar landing.

Not long afterward, the same President canceled the Apollo program—though he held off on making his announcement until after his reelection in 1972 was assured.

During the final lunar landing mission—Apollo 17, which left Earth on Dec. 7, 1972 and reached the moon on Dec. 11—Nixon was candid about what the future held for America’s exploratory ambitions, and it was not good. “This may be the last time in this century that men will walk on the moon,” he said in a formal pronouncement.

As it turned out, things have been even bleaker than that. It’s been 42 years since Apollo 17 commander Gene Cernan climbed up the ladder of his lunar module, leaving the final human footprint in a patch of lunar soil. TIME’s coverage of the mission provides not only an account of the events, but a sense—unintended at the time—of just how long ago they unfolded. There are the quotation marks that the editors thought should accompany the mention of a black hole, since really, how many people had actually heard of such a thing back then? There was, predictably, the gender bias in the language—with rhapsodic references to man’s urge to explore, man standing on the threshold of the universe. It may be silly to scold long-ago writers for such usage now—but that’s not to say that, two generations on, it doesn’t sound awfully odd.

Over the course of those generations, we’ve made at least one feint at going back to the moon. In 2004, then-President George W. Bush announced a new NASA initiative to return Americans to the lunar surface by 2020. But President Obama scrapped the plan and replaced it with, well, no one is quite certain. There’s a lot of talk about capturing a small asteroid and placing it in lunar orbit so that astronauts can visit it—a mission that is either intriguing, implausible or flat-out risible, depending on whom you talk to. And Mars is on the agenda too—sort of, kind of, sometime in the 2030s.

But the moon, for the moment, is off America’s radar—and we’re the poorer for it. There were nine manned lunar missions over the course of three and a half glorious years, and half a dozen of them landed. That makes six small sites on an alien world that bear human tracks and scratchings—and none at all on the the far side of that world, a side no human but the 24 men who have orbited the moon have seen with their own eyes.

We tell ourselves that we’ve explored the moon, and we have—after a fashion. But only in the sense that Columbus and Balboa explored the Americas when they trod a bit of continental soil. We went much further then; we could—and we should—go much further now. In the meantime, TIME’s coverage of the final time we reached for—and seized—the moon provides a reminder of how good such unashamed ambition feels.

Read a 1973 essay reflecting on the “last of the moon men,” here in the TIME Vault: God, Man and Apollo

TIME space

You Can Quit Thanking Comets for Your Water

Comet 67P: Does this thing look like it could quench your thirst?
Comet 67P: Does this thing look like it could quench your thirst? ESA

A new finding from the Rosetta spacecraft upsets a longstanding theory

There was no shortage of drama when the European Space Agency’s probe Philae set down on a comet last month—the first such landing in history. First Philae bounced, then it bounced again, ending up with one of its three legs sticking up in the air, and in the shadow of a cliff that prevented its solar panels from recharging its batteries. For two days, the probe hurried to complete whatever science it could….and then everything went black.

But that hardly spelled the end of the mission. Philae’s mother ship, Rosetta, has continued to orbit comet 67P/Churyumov–Gerasimenko, as it’s been doing since August, taking measurements and images of unprecedented quality. And with nearly a year of close-up observations to go, Rosetta has already come up with one result, described in a new paper in Science, that chief scientist Matt Taylor, of the European Space Agency, labeled “fantastic”: Earth’s oceans, the scientists have concluded, were evidently not created by impacts from comets rich with water ice, despite earlier evidence to the contrary. “We have to conclude instead,” said lead author Kathrin Altwegg, a planetary scientist at the University of Bern, at a press conference, “that the water came from asteroids.”

That’s a big reversal from what scientists were thinking just a few years ago. Back in 2011, the European Herschel space telescope took a hard look at Comet Hartley 2 and determined that its own cache of water, detected as vapor boiling away as Hartley approached the Sun, had a chemical composition very similar to what we see on Earth. It’s all H2O, but some of the H is a rare form of hydrogen known as deuterium, whose atoms carry not just a proton like the ordinary stuff, but a neutron as well. Water molecules made with deuterium are known as “heavy water,” and about three in a thousand water molecules on Earth’s surface are the heavy kind.

Measurements of Halley’s Comet back in the mid-80’s showed a deuterium-to-hydrogen ratio about twice that high, which argued against the idea that comets delivered water to a bone-dry Earth early in the Solar System’s history. But Halley’s came from the Oort Cloud, a spherical swarm of proto-comets orbiting at the far edges of the Solar System. Hartley 2 came from the Kuiper Belt of comets, which lies just beyond Neptune–not exactly nearby, but a whole lot closer. Given what Herschel found at Hartley 2, it appeared that Kuiper belt comets are chemically different from those that hail from the Oort cloud. If so, our water could have cometary origins after all.

The new results from Rosetta say no: Comet 67P, which also comes from the Kuiper belt, has an even greater proportion of heavy water than Halley’s and other Oort cloud objects. Even if significant numbers of comets do have Earthlike water, some clearly don’t—and even a relative few would have made Earth’s proportion of heavy water higher than it is. It’s arguable that 67P is pretty much unique among its Kuiper Belt brethren in having so much deuterium. “That’s not impossible,” said Altwegg dubiously “but….”

If comets didn’t bring us water, and if the Earth was too hot in its youth to hold on to what surface water it might have started out with, there’s still one plausible water carrier. “Today, said Taylor at the press conference, “we know asteroids have very little water, but that was probably not always the case.” The solar system was bombarded by asteroids early in its history, and if they were indeed wetter than they are now, that explains where the water in our oceans, in our seltzer bottles, in our bodies and everywhere else comes from.

Important as this new finding is, it’s likely to be only the first of many Rosetta will make as it rides along with 67P for the next year or so, watching carefully as the warming rays of the Sun bring the comet to life. “It’s a nice start to the science phase of the mission,” Taylor said.

And if you think you’ve heard the last of the Philae lander, think again. Mission controllers are still trying to pinpoint Philae’s precise location on 67P’s surface. That will allow scientists to do at least one more experiment: they’ll send radio pings from Rosetta through body of the comet to bounce off Philae and back to Rosetta. By examining how the radio beams are altered en route, they will be able to figure out whether 67P’s insides are rock-solid or held together relatively loosely.

Locating Philae would also allow scientists to calculate whether the lander might be brought back from the dead six months from now. It’s just possible, said Taylor, that a change in 67P’s orientation could bring Philae back into the sunlight, allowing its solar panels to recharge its batteries. If that happens, the prospects for extraordinary science from this already wildly successful mission will be even greater.

TIME space

Mars Curiosity Rover Finds Clues to Genesis of Ancient Lake

Geological observations helped scientists come up with a scenario for the creation of a lake bigger than Salt Lake

Geological observations from NASA’s Curiosity rover have helped scientists come up with a scenario for the creation of a lake that’s bigger than Salt Lake and a mountain that’s higher than Mount Rainier on ancient Mars.

The scenario suggests that water could have filled much of 96-mile-wide (154-kilometer-wide) Gale Crater 3.5 billion years ago or so, and that the 3.5-mile-high (5-kilometer-high) mountain in the middle of the crater could have been formed by repeated cycles of sediment buildup and erosion.

The findings provide further support for the view that ancient Mars could have sustained life as we know it on Earth…
TIME space

See 25 Incredible Images of Earth From Space

There’s something to be said for being on the ground when news plays out, but sometimes it’s the overhead view that provides the most unique perspective. Throughout 2014, DigitalGlobe’s satellites have captured scenes that gave us important glimpses into what was happening around us, from the unrest in Ukraine to fires in California. A leading provider of commercial satellite imagery, DigitalGlobe is holding its fourth annual Top Image contest and asking followers on Facebook to pick the year’s top picture. Vote here.

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