There (to an asteroid) and back again: a robot’s journey

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This Thursday, the OSIRIS-REx robotic probe will launch from Cape Canaveral in Florida, destined for asteroid Bennu. I can’t ride with the probe, but I’m doing the next best thing: going to Florida to watch the launch, alongside scientists involved in the project. Here’s a preview, written for New Scientist:

NASA probe about to leave for asteroid Bennu and bring bits home

For New Scientist:

Bennu or bust. On 8 September, the OSIRIS-REx probe will leave Earth for the asteroid Bennu, and will return with souvenirs: up to 2 kilograms of material from its surface.

OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) is the latest in a string of sample return missions, following the Stardust mission to the comet Wild 2 and the Hayabusa mission to asteroid Itokawa. Both of those missions hit hurdles, and neither brought more than a few grains of material back to Earth.

OSIRIS-Rex will pioneer a new and ambitious technique for gathering samples: a robotic arm equipped with a vacuum cleaner. [Read the rest at The New Scientist]

Don’t pull up stakes for the asteroid-mining gold rush

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Is Space Becoming a Gold Mine?

A new law grants private companies ownership over the materials they extract from asteroids or the Moon. But don’t call it a gold rush just yet

For The Daily Beast:

Asteroids are remnants of the Solar System’s youth. When the planets were forming more than 4.5 billion years ago, gas and dust molecules clung together to form larger objects, which in turn collided and stuck together to make yet bigger things. At the end of the process, we were left with the big planets, moons, and a huge number of smaller bodies which contain the raw chemicals we see on Earth.

Some asteroids could contain significant amounts of rare metals such as platinum, rare-earth elements, and other materials. Even water is a valuable resource in space, since it is useful as fuel (broken into hydrogen and oxygen components) and necessary for astronauts, but very heavy and therefore expensive to carry into space.

Now, President Barack Obama signed a bill into law granting private companies ownership over materials they extract from asteroids or the Moon. The bill also extends the period of time private corporations can develop spacecraft without direct government oversight, to help speed the process of getting more rockets into space.

But don’t pull up stakes for the asteroid-mining gold rush just yet. [Read the rest at The Daily Beast…]

Bathing asteroids with nuclear weapons

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A gentle nudge with a nuke: deflecting Earth-bound asteroids

From Ars Technica:

In 2013, a small asteroid exploded in the atmosphere over Chelyabinsk, Russia. The sonic boom from the event sent more than a thousand people to the hospital, mostly from flying glass from shattered windows. The Chelyabinsk meteor was a relatively small chunk of space rock—asteroid researchers think it was probably about 20 meters (66 feet) across—but exploding over a city made it a noteworthy event. It’s probable many similar asteroids hit Earth on a regular basis, but most don’t happen to fly over metropolitan areas; they fall into the ocean or over lightly populated regions.

However, Earth has played target in the cosmic darts tournament before. Meteor Crater in Arizona, the Tunguska impact in Siberia in 1908, and most famously the Chicxulub asteroid in Mexico (which played a part in the extinction of the dinosaurs) are just three of many known examples. That’s why many people are looking at viable options for planetary defense: destroying or turning asteroids aside before they can hit Earth. And planetary defense is one reason the United States’ National Nuclear Safety Administration (NNSA) has given for not destroying some of its surplus nuclear warheads. [Read the rest at Ars Technica…]

A space robot arrives at a new world: Dawn at Ceres

The asteroid dwarf planet Ceres, in a view showing the intriguing two bright spots. [Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA ]

The asteroid dwarf planet Ceres, in a view showing the intriguing two bright spots. [Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA ]

Sunday is my birthday, and NASA kindly decided to give me a whole asteroid. I got to write about it for The Daily Beast.

NASA’s Dawn Spacecraft Made It to Dwarf Planet Ceres

From The Daily Beast:

When I was young, I obsessively read through a National Geographic science book called Our Universe, a good overview of current astronomy and especially the Solar System. Voyager 2 was cutting edge at the time, which gives you a hint of when this was. One chapter was devoted to asteroids, the small rocky bodies scattered throughout the inner Solar System and especially the region between Mars and Jupiter. At that time, we didn’t have clear photos of any of them, so the book had paintings of Ceres, Vesta, Pallas, and several asteroids. My mental image of Ceres for more than 30 years has been that artist’s impression: a perfectly spherical, heavily cratered object, colored a light gray.

I mention this because for the first time in history, we now have real photos of Ceres, thanks to NASA’s Dawn spacecraft. Dawn entered orbit around Ceres today, providing us with our first close-up views during its approach. [Read more at The Daily Beast…]

Artist's impression of the ringed asteroid Chariklo. While the asteroid is too small and distant to image directly, astronomers found two narrow rings around it — making it the smallest known object with a ring system. [Credit: ESO/L. Calçada/M. Kornmesser/Nick Risinger (skysurvey.org)]

Artist’s impression of the ringed asteroid Chariklo. While the asteroid is too small and distant to image directly, astronomers found two narrow rings around it — making it the smallest known object with a ring system. [Credit: ESO/L. Calçada/M. Kornmesser/Nick Risinger (skysurvey.org)]

Saturn’s magnificent rings have been known since Galileo observed the planet’s “ears” in his telescope. In the last few decades, researchers found rings (albeit less shiny ones) around the other giant planets — Jupiter, Uranus, and Neptune. And now the small asteroid Chariklo has joined the ring cycle: observations revealed it has two narrow rings, probably composed of water ice. It’s an intriguing discovery, since nothing else we’ve found at intermediate sizes has rings, leading to questions of how they form, how stable they may be, and whether there might be other beringed objects out there.

Beyond size, another challenge is Chariklo’s location between Saturn and Uranus. It orbits in a long ellipse, ranging from 13 to nearly 19 times farther from the Sun than Earth. This position, along with its composition of rock and ice, marks Chariklo as a “centaur.” Just like mythological centaurs are half human and half horse, astronomical centaurs combine features of asteroids and comets. (Centaurs would grow comet-like tails if they fell closer toward the Sun.) Tens of thousands of centaurs may lurk among the giant planets, though most of those are much smaller than Chariklo, the largest known centaur. [Read more…]

All the single centaurs

Vesta is the second-largest asteroid in the Solar System, and recent measurements by the Dawn mission showed that it’s actually a protoplanet: a piece of planet-like material left over from the early days of our Solar System. However, Dawn is significantly non-spherical and very battered. Most notably, it has two huge overlapping craters near its south pole, marking impacts that nearly shattered the asteroid, and which raised a mountain higher than any other in the Solar System. Now, a computer simulation may have showed how Vesta came to be the fascinating, scarred, wonderful object we see today.

As with other Solar System bodies, Vesta bears the scars of its history. The most substantial of these scars are the two large impact basins, Veneneia and Rheasilvia. (Both craters were named for virgins who served the goddess Vesta in Roman mythology—the vestals.) Rheasilvia formed about 1 billion years ago and is larger. Veneneia is smaller and formed at least 2 billion years ago; its presence was partly obscured by the later impact. Meteorites from Vesta, possibly ejected by the impacts forming Rheasilvia and Veneneia, have been found on Earth. [Read more….]

Kaboom! A simulation shows how impacts shaped and nearly destroyed Vesta