Traces of salty water on Mars … and more mysteries!

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[Credit: Randall Munroe]

Water Found on Mars Could Be First Signs of Martian Life

NASA’s Mars Reconnaissance Orbiter found traces of water that comes and goes on Mars—aka flowing water

For The Daily Beast:

We seem to discover water on Mars about once a year. Well, that’s not quite true: we’ve known Mars has water for quite a while. However, there are a lot of mysteries still to solve about how that water behaves and where it’s located. In particular, we’d like to know if water sometimes flows on the surface of the planet, which would tell us a lot about the cycles both above and below ground. And of course water is essential for life as we know it—finding flowing water, even transient flows, would make Mars seem a little more Earth-like.

The problem is that any liquid water evaporates quickly in the bone-dry Martian desert, and other processes can leave traces that mimic dried-up flows. When so little water is involved in the first place, it leaves us looking for the Martian equivalent of water spots on a long-dry drinking glass. And those spots are chemical traces—salt and other minerals once dissolved in the water—which must be identified by robotic spacecraft from orbit.

Today, scientists using NASA’s Mars Reconnaissance Orbiter (MRO) have identified some of those traces: a little bit of water comes and goes on Mars’ surface. [Read the rest at The Daily Beast…]

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Pluto: what’s in a name?

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

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.

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

The week in review (September 1-7)

A full-size wooden mock-up of the Lunar Atmosphere and Dust Environment Explorer (LADEE). [Credit: moi]

A full-size wooden mock-up of the Lunar Atmosphere and Dust Environment Explorer (LADEE). [Credit: moi]

The last week was especially busy because I attended the launch of the Lunar Atmosphere and Dust Environment Explorer (LADEE) at NASA’s Wallops Flight Facility. I will have a lot to say about that launch, LADEE, and related topics later on, but suffice to say it was a great experience — increased because it was my first successful rocket launch viewing. (I attempted to watch the Antares rocket test in April, but that was scrubbed at the last minute and I couldn’t attend the rescheduled launch.) So, here’s my very small list of articles published this week.

  • Turbulence ahead: Interstellar wind changes direction, blows faster (Ars Technica): The Solar System orbits the center of the Milky way, and as it does, it’s passing through a diffuse nebula known as the Local Interstellar Cloud (LIC). Various satellites and probes have measured the passage of atoms through the Solar System since the 1970s; analysis of that data shows that the direction of this wind has changed and its rate has picked up. That reveals some interesting new detail about the environment surrounding the Solar System.
  • Of maps and math and Buckminster Fuller (Galileo’s Pendulum): Mapmaking will never be perfect because there’s no way to create a flat representation of the curved surface of Earth without some distortions. This post goes a little into the math of projection, the art of converting positions on a globe onto a flat map, and how the eccentric utopian architect Buckminster Fuller tried to solve the problem. The result was his wonderful Dymaxion map, which as a physicist I’m very fond of.

I also wrote a brief viewing guide for the LADEE launch, which is now necessarily obsolete. However, you can find a lot of photos and video from the launch at NASA’s LADEE site.