Testing Einstein’s theory with a new space probe to Mercury

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And if I can be shameless: Forbes pays according to traffic, so the more of you who share and visit and read my stuff, the better they pay me. Ahem.

New Mercury Space Probe Will Put Einstein’s Gravity To The Test

orbit of Mercury, including effects from general relativity and other planets in the Solar System

The orbit of Mercury, including effects from general relativity and other planets in the Solar System. I’ve exaggerated the effect for easy viewing; in real life, the orbit is very nearly an ellipse. [Credit: Matthew R Francis]

For Forbes:

Despite the discovery of other galaxies, black holes and other marvelous astronomical bodies, we keep returning to the orbits of planets to understand gravity at its most basic. Partly that’s simplicity: We’re inside the Solar System and can make measurements without spending billions of dollars or building virtual observatories the size of the whole planet. But that doesn’t mean we’ve exhausted all the ways to learn about gravity from the dance of the planets.

In a new paper in Physical Review Letters, University of Florida physicist Clifford Will showed that the upcoming BepiColombo space probe may be able to test an aspect of Albert Einstein’s theory of gravity, general relativity, that’s been out of reach so far. This effect comes from the gravity of other planets in the Solar System, leading to a tiny shift in Mercury’s orbit. But small doesn’t mean unimportant: If general relativity needs to be modified on this tiny level, the BepiColombo probe may be able to spot that discrepancy.

[Read the rest at Forbes…]

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]

Pluto: what’s in a name?

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Pluto and Other Truly Epic Space Photos

For The Daily Beast:

To quote another great space adventurer: “Almost there!”

The New Horizons probe, launched in 2006, will finally reach Pluto next Tuesday, providing the first close-up view of the tiny, icy world since we discovered it in 1930. We’re already seeing features never glimpsed before. It’s a truly historic occasion, right up there with the Dawn mission to the giant asteroid Ceres, known since 1801 but never seen clearly before this year.

But what is Pluto? [Read the rest at The Daily Beast…]

Yes, I dive again into the “is or isn’t Pluto a planet”, and declare a pox upon both parties. Well, at least I call the IAU definition “crap” and make fun of the Pluto monomaniacs who insist that of course Pluto is a planet. Either way, though: I love Pluto, and I am very much looking forward to Tuesday.

P.S. Though we now have some excellent photos of Pluto and are getting more literally daily, the featured picture for my article is the bottom of a frying pan. Go figure.

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…]