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Top 10 Space Moments

1. An SUV Heads to Mars

By Jeffrey KlugerWednesday, Dec. 07, 2011

NASA / JPL / Reuters

Think the existing Mars rovers or the lunar dune buggies from the Apollo days were fun? Wait till Curiosity — an SUV-size rover that left Cape Canaveral in November — arrives on Mars on Aug. 6. The rover will be the biggest, most capable machine on the Red Planet by far, and it will get there in an improbable way — plunging through the Martian atmosphere, slowing itself down with parachutes and air resistance and then being lowered by cables from a hovering propulsion shell. A first act like that will be hard to follow, but the second act — at least two years of Martian exploration — will probably be more than up to the job.

2. ET Arrives — or at Least His Raw Material

By Jeffrey KlugerWednesday, Dec. 07, 2011

Chris Smith / NASA's Goddard Space Flight Center

No one knows how the first organisms — or even the first organic precursors — formed on Earth, but one theory is that they didn't. Rather, they were imported from space. Scientists have been finding what looks like biological raw material in meteorites for years, but it's usually been shown to be ground contamination. This year, however, investigators studying a dozen meteorites that landed in Antarctica found traces of adenine and guanine — two of the four nucleobases that make DNA. That's not a big surprise, since nucleobases have been found in meteorites before. But these were found in the company of other molecules that were similar in structure but not identical. Those had never been detected in previous meteorite samples — and they were also not found on the ground where the space rocks landed. That rules out contamination — and rules in space organics. A little adenine and guanine in the company of other mysterious stuff is a long, long way from something living — but it's closer than we were before.

3. Star Wars Gets Real

By Jeffrey KlugerWednesday, Dec. 07, 2011

Mary Evans / Ronald Grant / Everett

Here's a movie-geek screening test: What is Tatooine? If you said Luke Skywalker's home world, a desert planet with two suns, you pass. In September, researchers announced the discovery of a planet, now dubbed Kepler 16b, that, just like Tatooine, orbits a binary star system. Binary stars are not uncommon in the galaxy, but they were always thought to be gravitationally dangerous places for a planet to be. When two elephants are waltzing, you don't want to be the mouse that gets underfoot. With the help of the Kepler space telescope, however, scientists from the SETI (Search for Extraterrestrial Intelligence) Institute found subtle dips in the light coming from a binary system about 200 million light years from Earth. The dips were an average of 229 days apart — a pretty solid sign that a planet is orbiting both stars, passing first in front of one, then in front of the other. No droids or galactic cafés are likely there, however. Unlike the real Tatooine, this one is deep-frozen at about –100°F (–73°C).

4. Legos Go to Jupiter — Oh, and a Spaceship Too

By Jeffrey KlugerWednesday, Dec. 07, 2011

BRUCE WEAVER / AFP / Getty Images

Jupiter and its swirl of moons got a good going-over by the Galileo spacecraft when it orbited through the Jovian system from 1995 to 2003. But a lot of questions remained unanswered about the planet's interior, magnetic field, chemistry and weather. Now NASA's going back with the Juno spacecraft, launched in August and slated for arrival in 2016. The ship will enter a polar orbit around Jupiter — circling the planet north to south instead of along its waistline — which should provide both new science and stunning new images. And then, of course, there are the Legos. Tucked inside the ship are Lego figurines of the Roman god Jupiter, his wife Juno and Galileo Galilei, who discovered the four large moons of Jupiter in 1610. Affixed to the side of the ship is also a plaque bearing Galileo's likeness and a diary entry in the great man's own hand, describing the moons' discovery.

5. A Jewel the Size of a Planet

By Jeffrey KlugerWednesday, Dec. 07, 2011

Swinburne Astronomy Productions

Take that, Tiffany's. About 20 quadrillion miles from Earth is a decidedly unusual planet. It's not its size — about the diameter of Jupiter — that makes it special; rather, it's its composition. The planet is thought to be made mostly or even entirely of diamond. The improbable world orbits a body known as a pulsar — an ex-star that exploded and collapsed in on itself so that it is now a rapidly spinning, superdense mass emitting powerful bursts of radio waves with each rotation. The diamond world was once a star too, and it too eventually burned out and blew up. The core it left behind would be mostly oxygen and carbon, and its own great mass would have crushed that carbon down to crystalline form — in other words, into diamond. We'll leave it to jewelers to calculate the karats — but 5 or 6 kajillion is a pretty good bet.

6. An Overlooked Planet Gets Its Closeup

By Jeffrey KlugerWednesday, Dec. 07, 2011

NASA / Getty Images

Remember Mercury? Sure you do — first planet in the solar system, hot as blazes on one side and paralyzingly cold on the other? You could be forgiven for overlooking Mercury since NASA itself hadn't given it much thought since 1974, when the Mariner 10 probe made a few flybys. This year, the space agency made up for that when the Messenger probe went into orbit around Mercury, becoming the first spacecraft ever to achieve that singular bit of flying. The mission, designed to study Mercury's surface and interior and learn more about its origins, was intended to end in 2012, but it's going so well it's been extended until 2013. The innermost planet may not have the beauty of a Saturn or the biological potential of a Mars, but every world deserves a little love — and the baby of the sun's brood is finally getting its share.

7. That's One Thirsty Black Hole

By Jeffrey KlugerWednesday, Dec. 07, 2011

NASA / ESA

We don't think of space as a very wet place, but the cosmos is fairly awash in water in its solid, liquid and gaseous forms. That familiar truth, however, did not prepare two international teams of astronomers for what they discovered last summer: a black hole 20 billion times the mass of our sun surrounded by — and sucking in — a cloud of water vapor equivalent to 140 trillion times the mass of Earth's oceans. For sheer, jaw-dropping numbers you could stop there. But the scientists are using their discovery in an ingenious way: studying the swirl of the water cloud to make inferences about the structure of the black hole itself. Just like astronomers: no sooner do they discover something wonderfully, pointlessly cool than they find some practical way to use it.

8. Orbiting Vesta — Thanks to Ions

By Jeffrey KlugerWednesday, Dec. 07, 2011

Miami Herald / MCT / LANDOV

Thanks to ions: Deep in the asteroid belt is a rock the size of Arizona. It's called Vesta, it's the second biggest asteroid in the band of rubble between Mars and Jupiter, and in July it got a visitor: the Dawn spacecraft, which settled into orbit around Vesta, where it will remain for a year, studying what is one of the oldest objects in the solar system. Dawn traveled to Vesta in a whole new way: ion propulsion, which relies on a stream of xenon ions to nudge a spacecraft along on a gentle but steadily accelerating glide. Goodbye, heavy, traditional fuel — and hello, asteroid. When Dawn is done with its work, it will puff its way out of orbit and head for Ceres, the solar system's largest (Texas-size) asteroid, and repeat the same surveillance. One ship, two stops — not half bad.

9. U.S. Astronauts Have to Hitch a Ride

By Jeffrey KlugerWednesday, Dec. 07, 2011

SERGEI ILNITSKY / AFP / Getty Images

Americans took pride in beating the Russians to the moon during the long-ago space race. Now we're lucky if they let us ride shotgun aboard their Soyuz spacecraft. The mothballing of the shuttles meant NASA's astronauts would have to be hitching rides with the Russians for however many years it takes the U.S. to get its next-generation spacecraft built. But when an unmanned Soyuz sent up on a resupply run crashed in August, it looked as if both countries might be grounded — and the International Space Station might have to be abandoned until things could be sorted out. The fact that the problem got fixed and milk runs to the station resumed put that worry on hold — but hardly addressed it completely. With the U.S. unlikely to have a new crew-worthy vehicle available until 2016 at the earliest, a permanent solution is still years away.

10. One Last Ride

By Jeffrey KlugerWednesday, Dec. 07, 2011

Dan Winters for TIME

Few things became the shuttle program as well as its ending. After 135 flights of the snakebit space planes, the shuttle Atlantis took off last July — defying the weather as it found a lucky gap in the clouds and launched almost precisely on schedule. Its landing, after 13 days aloft, was equally textbook. It was a time for valedictories for the vehicle itself, the astronauts who flew it and particularly the 14 whose lives the shuttle program claimed. The surviving shuttles will now be museum pieces, a role in which they can do no harm — serving as reminders of ingenuity, courage and, alas, bureaucratic folly.

Cosmonautics Day, April 12

Cosmonautics Day, celebrated on April 12, commemorates the first ever manned flight into outer space by one of the world's most timeless pioneers: Yury Gagarin.

In November 1957, Laika, a stray dog from Moscow, was launched into space in a 508-kilogram Sputnik-2 capsule and became the first animal to orbit the Earth. Laika's flight proved living beings could survive the conditions of outer space, but could humans undergo a similar test of endurance and live to tell the tale? 

Roughly three years after Laika's mission, on Apr. 12, 1961, the 27-year-old Russian cosmonaut Yury Gagarin followed suit and made history as the first man to orbit the Earth. His flight lasted 108 minutes from launch to landing. 

According to NASA, the physical hazards of weightlessness at the time of Gagarin's flight were almost wholly unknown.

Puzzle of Moon’s origin resolved

Simulations show that Earth probably collided with an unnervingly similar sister planet to form our lunar neighbour.

• Adam Levy

08 April 2015

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Hagai Perets

It now seems more probable that a collision between two planets of similar composition led to the formation of the Moon.

A nagging problem at the heart of the leading theory of how the Moon formed seems to have been explained away.

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Reporter Adam Levy finds out how a new simulation reveals a hidden relationship between the Earth and the Moon.

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The ‘giant impact’ hypothesis, first proposed in the 1970s, suggests that the Moon was formed from the debris scattered when a Mars-sized planet slammed into the early Earth some 4.5 billion years ago. This fits well with what we know about the Moon, including its mass and lack of any significant iron core.

But the theory also implies that the Moon is made up mostly of impactor material. Since lunar and Earth rocks have such similar compositions, this suggests that Earth and the planet that smacked into it resembled each other too. They would have needed to be sister planets, with a relationship much closer than that of any other planetary bodies we have studied in our Solar System. The odds of this being possible were thought to be around a 1% chance, or “uncomfortably rare”, according to Robin Canup, a planetary researcher at the Southwest Research Institute in Boulder, Colorado¹.

Better odds

Now it seems that the scenario is not so far-fetched, says Hagai Perets, an astrophysicist at the Israel Institute of Technology in Haifa. He and his colleagues performed simulations of the Solar System’s formation, to investigate how similar planets tend to be to their last giant impactor. They estimated that for 20% to 40% of collisions, the two bodies would be sufficiently similar to explain the Moon’s composition — considerably better odds. The findings are published in Nature².

The planets would have closely resembled each other because of their similar distance from the Sun, meaning that they would have formed from the same kind of orbiting proto-planetary material. “The Earth and the Moon are not twins born from the same planet, but they are sisters in the sense that they grew up in the same environment,” says Perets.

Nature

 

doi:10.1038/nature.2015.17279