When it comes to new movies, I tend not to read a lot about them in magazines or on the Web — at least for ones I really want to see. I'll put aside the Entertainment Weekly cover story about a new big-budget sci-fi movie (say, the forthcoming remake of The Day the Earth Stood Still) until after I see the film, because I don't trust the article writers to keep plot points to themselves. I don't want to spoil any surprises. This is the reason I haven't sought details about the upcoming new James Bond film, Quantum of Solace. I've seen the trailer, but that's all I want until I go see it after it opens in theaters in four weeks.

That said, I know there's an astronomical angle to the movie. Some of it was filmed at European Southern Observatory's Very Large Telescope (VLT), as seen at right. They're having quite a year, also being also featured on the National Geographic Channel tonight. I don't know exactly how VLT will be used in the film, though it's probably some kind of weapon — and I don't want to know! But, if you're not like me, check out ESO's promotional stuff about the movie at Bond@Paranal. The Flash movie "trailer" is quite cute, but I'm not going to watch any interview with producers just yet.

Fellow editor and sometime couch potato Dennis di Cicco told us all today at our editorial meeting that if you don't want to watch the last U.S. presidential debate, you may want to tune in to the National Geographic Channel for an episode of World's Toughest Fixes.

I've seen the ads for this show, but have yet to watch it. I'll at least be recording this week's episode airing at 10 p.m. EDT Wednesday (check the NGC's website rebroadcast times throughout the next three weeks). The host, Sean Riley, will be atop Chile's Cerro Paranal to watch (help?) technicians realuminize one of the 8.2-meter mirrors of European Southern Observatory's Very Large Telescope (VLT).

What would you call a towering ring of clouds that swirls around at 300 miles per hour? A hurricane, right?

But atmospheric scientists are stopping short of using that word to describe the monstrous cloud rings they've now found encircling both of Saturn's poles. New visible-light and infrared images from NASA's Cassini orbiter, released yesterday, show that the terrestrial-hurricane analogy only goes so far. That's because these titanic cloud systems dwarf anything on Earth. In fact, when I first saw this one, at the planet's bottom, all I could think of was "Wow!"

Since Saturn's south pole has enjoyed constant sunlight since the spacecraft arrived in July 2004, the Cassini team has gotten to study the southern vortex extensively. Earlier looks had shown a double-ring structure, but the new views reveal even more complexity. The dominant cloud wall is 18,000 miles (30,000 km) across — about twice the size of Earth! — and stands 30 to 40 miles tall. By comparison, the eye wall of a terrestrial hurricane is typically less than 10 miles high.

"We can infer that these are truly towering clouds," explains team member Andrew Ingersoll, an atmospheric specialist from Caltech. "Everyone warned me that I shouldn't call this a hurricane, because it's locked on the pole and there's no ocean below to supply the heat to drive it."

Ingersoll notes that the flow around the southern pole is cyclonic (clockwise), indicating a low-pressure system. The interior looks darker because the gas there warms as it moves downward into higher pressures, and that causes clouds to evaporate. However, puffy knots of convective clouds, themselves looking like tiny swirling hurricanes, dot the polar region. These rising cells might be supplying heat from deeper in the atmosphere to keep the system energized.

"So what is it?" Ingersoll muses aloud. "Darned if I know."

He admits that for now the team members are simply trying to characterize what they're seeing. "We're still in the butterfly-collecting phase," he quips.

Meanwhile, he and other mission scientists have known since the 1980s (thanks to the Voyager flybys) that a strange, hexagon-shaped cloud feature some 15,000 miles (24,000 km) across surrounds the planet's northern pole. The cause of its polygonal shape is unclear, though it probably arises from back-and-forth wave motion that takes exactly six cycles to circle the pole at that latitude.

Cassini has been probing the northern structure at infrared wavelengths because the pole has been hidden in nighttime shadow. A particularly good flyover by the orbiter last June revealed many details not previously seen — including another huge vortex inside the hexagon.

The northern vortex is also a cyclonic (low-pressure) system — but, unlike its southern counterpart, it has a bright center. "We don't have an eye — we have a belly button," explains investigator Kevin Baines (Jet Propulsion Laboratory). He reports that winds in this bright core have been clocked at about 350 miles per hour, then fall off in the surrounding broad dark annulus of downwelling gas, then again kick up in the hexagon.

Like its counterpart down south, the northern vortex is dotted with "little" cloud puffs hundreds of miles across that appear to be energized from below.

The head-scratching at Cassini Central probably won't last too much longer. Northern spring is coming on Saturn, and by next year Cassini's visible-light camera should be able to work in concert with the infrared spectrometer to study the northern vortex and hexagon exhaustively.

It's been more than three years since NASA's Deep Impact mission hurled an 815-pound copper-clad bullet into the path of Comet 9P/Tempel 1, and scientists are still struggling to understand the gigantic plume of dust and water vapor that spewed into space from the target point.

A big part of the problem is that the gigantic cloud obscured the comet's nucleus until long after the main spacecraft had passed by. To this day, the mission team can only guess at the size of the crater creted by Deep Impact's frontal assault. By one well-regarded estimate, it could be anywhere from about 80 feet (25 meters) to more than 350 feet (100 meters) across — depending on whether the cometary surface was hard or fluffy.

Regardless, NASA sure got a lot of bang for its bucks. At this week's big meeting of planetary scientists at Cornell University, Michael Küppers (European Space Agency) noted that the impact liberated some 200,000 tons of material, which is roughly 50,000 times the mass of the impactor and nearly 100 times more than had been predicted.

So what happened?

First, Küppers concludes that Tempel 1's nucleus must be incredibly porous and weakly held together by gravity alone, rather than by its material strength. That's the general consensus among the experts, because it's the only way so much material could have been liberated. (Hmm . . . but if that's the case, then how has the nucleus managed to retain so many craters, as seen at right?)

Second, he speculates that the impact must have punched through to a layer of water frozen as amorphous (not crystalline) ice. This form of ice is what theorists expect to find in comets that came together at temperatures below –190°F (–125°C). Michael A'Hearn, Deep Impact's principal investigator, explains that amorphous ice would rapidly convert to its crystalline form once exposed to space and liberate lots of heat.

It's also conceivable that all those eons that Comet Tempel spent in the solar system's deep freeze, far from the Sun, allowed galactic cosmic rays to ionize the ices both on its surface and deep into its interior. That could have set the stage for an explosive chain reaction too. But it also would have created all manner of strange compounds to come hurtling out of the comet's interior, and A'Hearn notes that Deep Impact saw nothing of the sort.

Interestingly, other scientists at the meeting noted that amorphous ice might hold the key to the dramatic displays put on last year by Comet McNaught and Comet Holmes.

A few weeks ago I learned of a curious discovery out beyond Neptune. The object itself, dubbed 2008 KV₄₂, was no bigger than about 30 miles (50 km) across — no threat to Pluto and Eris as the new king of the Kuiper Belt.

What caught my attention was the inclination of its orbit: 104°. In other words, the path it takes around the Sun is tilted up and over so much that the motion is more "backward" than "forward." Astronomers sometimes term this a retrograde orbit.

It's the first known retrograde trans-Neptunian object, but it didn't seem like that big a deal at the time. After all, 17 asteroids are similarly headed the wrong way around the Sun.

But today, at a meeting of the American Astronomical Society's Division for Planetary Sciences, I learned that 2008 KV₄₂ might be more archetype than oddball. Brett Gladman, a member of the discovery team, explained that this find could be the "missing link" in a long-running cometary conundrum. (I also learned that he and his observing buddies have nicknamed their find "Drac," because Dracula and other vampires purportedly could walk on walls.)

Gladman, J. J. Kavelaars, and Jean-Marc Petit found it on May 31st while trolling for just such high-inclination objects using the Canada-France-Hawaii Telescope atop Mauna Kea in Hawaii.

Comets follow one of three general paths as they plunge toward the Sun. Jupiter-family comets glide in close to the major planets' orbital plane. Most eventually encounter Jupiter and become trapped in tighter, short-period paths around the Sun. The thinking goes that they must originate either from the "classical" Kuiper Belt, a loose disk of bodies that lurk from Neptune's orbit out to about 55 astronomical units (a.u.), or from what are termed "scattered-disk objects," which have eccentric but low-inclination orbits.

Nearly isotropic comets, meaning they come screaming in from pretty much any direction, originate in the outer Oort cloud at least 10,000 a.u. from the Sun. Finally, Halley-type comets, named after the most famous ice ball of them all, have orbits that are highly inclined and often retrograde (as Halley's is).

Despite their best efforts, dynamicists have yet to puzzle out how the Halley-types ended up so skew to the rest of the solar system. Computer models that simulate long-term orbital evolution haven't been able identify a source region in either the Kuiper Belt or the more distant Oort cloud.

Gladman has a hunch that 2008 KV₄₂ might provide some clues. Its average distance from the Sun is 32 a.u. and comes its closest near the orbit or Uranus. So does 2002 XV_93, which is inclined steeply at 77°. But Uranus doesn't have enough mass to have yanked these so far up, Gladman says. So, for now, he's headed back to the dynamical drawing board.

Wow, there's nothing like an asteroid slamming into Earth to get professional and amateur astronomers whipped into a frenzy.

That's what happened on Monday morning when Maine skywatcher Bill Gray noticed something unique about a small asteroid discovered the previous night by Richard Kowalski and others at an observatory in Arizona. Gray's electronic posting to other asteroid aficionados began, "It looks as if Mt. Lemmon has found the first object . . . with a near certainty of hitting the earth."

Never mind that the object (designated 2008 TC₃), was no bigger than a car, so in all likelihood it would explode harmlessly in the atmosphere with the kinetic-energy equivalent of 1,000 or 2,000 tons of TNT. That's no big deal as impacts go — objects of that size and energy hit somewhere on Earth every month or so.

Even so, the world's astronomers kicked into high gear, amassing 570 observations between the space rock's discovery until it slipped into Earth's shadow about an hour before impact. All that in just 19 hours! My email in box was lit up like a Christmas tree! As the observations piled up, dynamicists at JPL boldly announced that the mini-asteroid would slam into Earth at 2:46 Universal Time on October 7th. Ground zero was somewhere over northern Sudan — and at night! For anyone in that part of northeast Africa, it was going to be quite a show.

So what happened? The impact did occur as predicted, but so far there's no confirmation that anyone on the ground saw it. S&T contributing editor Johnny Horne, who's a photographer for the Fayetteville Observer, received a negative report from Khartoum, Sudan's capital. Khartoum and Mecca are the closest significant cities to the impact site, but each is still roughly 300 miles away. This part of the world is exceedingly arid and sparsely populated — people living there have far bigger issues on their minds.

Nor have we received any confirmed sightings from countless observers in Europe who went out in the hopes of seeing the flash.

However, Peter Brown, a meteor researcher at the University of West Ontario, reports that the airburst was recorded by at least one infrasound sensor operated by the International Monitoring System, whose primary purpose is detecting surreptitious nuclear tests. Brown confirms that the impact energy ranged from 1,100 to 2,100 tons of TNT.

Visually, the most compelling evidence comes from nighttime visual and infrared images acquired by the European Space Agency's Meteosat 8 weather satellite. Zdenek Charvat (Czech Hydrometeorological Institute), who first noticed the flash in the Meteosat images, reports that the spot is apparent in all 12 spectral channels, which span wavelengths from 0.5 to 14 microns).

But the satellite's scanning imager takes about 5 minutes to record each frame, so there's no way to extract the exact time of the spot's appearance. But the flare seems to be in the right spot, corresponding to longitude 32.37° east and latitude +20.89° and an altitude of 14 to 20 miles (22 to 30 km). One frame hints at an apparent trail about 2 miles long.

Meanwhile, telescopic observations show that 2008 TC₃ was gyrating wildly before it hit. According to Czech asteroid specialist Petr Pravec, it was "definitely a tumbler." His analysis reveals two distinct periods of 49 and 98 seconds long. One is probably due to rotation and the other to spin-axis precession, but he can't tell yet which is which. But he notes that this ranks (or ranked!) as one of the three fastest-spinning asteroids known.

"It would be good to mention the role of Marek Kozubal and Ron Dantowitz at the Clay Center Observatory" Pravec told me. "Their photometric observations of the asteroid have been unique, and without them we wouldn't know much about its rotation."

I don't think we've heard the last word on this little party-crasher. After all, the U.S. Department of Defense has "assets" well suited to recording explosions in that part of the world. And from time to time the DoD's scientists have shared what they know with their civilian counterparts. So stay tuned for further developments!

If you don't see an image at top right, click here to see a 300-Kb animated image of the meteroid while it was still in flight. And you can read our original announcement here.

Spacecraft encounters with planets always give me an adrenalin rush, and a just-concluded one on October 6th was no exception.

NASA’s Messenger spacecraft zipped past Mercury Monday morning (4:40:21 a.m. EDT for those of you who’re truly curious), brushing within 125 miles (200 km) of its Sun-baked surface, and the pictures recorded during the flyby streamed back to Earth early the next day. It’s an incredible landscape — cratered plains splashed with bright craters that will keep the mission’s geologists giddily busy for a long, long time.

They’re giddy because we’re finally seeing a side of Mercury that’s never been revealed at close range. Mariner 10 didn’t glimpse it despite three flybys in 1974-75, and Messenger itself was looking elsewhere during its first visit back in February. Astronomers back on Earth have tried mightily to glimpse this terra incognita using giant telescopes and radar. Amateur astronomers played a role too, with some genuinely useful results.

The image spotlighted at right just fascinates me. Click on the image to enlarge it, and then take a good, long look. The very bright crater just below center, named Kuiper, had been spotted by Mariner 10, but not the crater splash along the limb at upper right. What’s caused the incredible web of thin, stringy crater rays that are draped across the landscape?

I can’t wait for the mission’s geologists to explain how debris ejected from a crater can stripe the surface so uniformly for hundreds of miles. And I suspect they’ll puzzle it out soon. After all, this picture was taken by Messenger’s wide-angle camera about 90 minutes after the spacecraft passed closest approach to Mercury, when the spacecraft was some 17,000 miles (27,000 km) away. One can only imagine (for now) all the exquisite details revealed by its telephoto camera from closer in.

Maybe I’ll get some answers for you next week, when I head to Cornell University to attend a major meeting of planetary scientists. Messenger took 1,200 images during this visit, along with a host of other measurements that will help reveal the composition of Mercury’s surface and atmosphere, the state of its magnetic field, and (fingers crossed) the structure of its interior.

As incredible as these images look, I keep having to remind myself: “Messenger really hasn’t gotten to Mercury yet.” Sure, it’s had two great flybys to date, and there’s a third next September. But this instrument-laden craft won’t really get down to business until it starts orbiting Mercury on March 18, 2011. That’ll be a Friday. Note to self: “Tell boss I’m busy that day.”

Update October 10, 2008

Click here to see the latest observations of this meteor. The original story, posted on October 6, 2008, continues below.

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Many telescopes around the world are dedicated to scanning the sky, looking for asteroids that might potentially hit Earth. Many candidates have been found, and some have received widespread coverage in the mainstream press. But when the trajectories have been computed, all of them have turned out to be false alarms — until now!

Last night (Sunday, October 5th), a telescope on Mount Lemmon, Arizona, detected a tiny moving blip, the signature of a small chunk of rock moving rapidly through space. Twenty-five observations have been done since then by professional and amateur astronomers around the world, and the object's orbit has been pinned down with fairly high precision. It is almost certain to hit Earth's atmosphere around 10:46 p.m. EDT tonight, October 6th. (That's 2:46 a.m. October 7th, Greenwich Mean Time.)

The rock is roughly 10 feet (3 meters) across, and it's expected to enter the atmosphere above northern Sudan at about 8 miles (12 km) per second. The energy released should be approximately equal to one kiloton of conventional explosives. Fortunately, no damage is expected, since the blast will take place in the upper atmosphere. Some fragments may fall to the ground, but the area is sparsely inhabited and they're unlikely to hit anyone.

The sight and sound, however, should be amazing — especially since the sky will still be dark when this meteor hits. The fireball may be visible over much of northern Africa, the Middle East, and possibly even southern Europe.

Technical details are available in the Minor Planet Electronic Circular.

Posted by Tony Flanders, October 6, 2008

Some amateur astronomers can't live without their Clear Sky Chart, the handy graphic that forecasts such need-to-know atmospheric conditions like cloud cover, transparency, and humidity. The major problem with Attilla Danko's fabulous service is that it's only available for North America — most of it, anyway.

We received word this morning that now the rest of the world can benefit from a similar website built by Chinese programmer Ye Quanzhi. His Astroweather Panel covers everywhere Clear Sky Chart does not. Select a location by entering your geographic coordinates, or navigate through the place names, organized by country, already in the system.

Check it out and please post a comment below with your experiences.

OK, I’ll admit it: With so NASA many missions under way right now, it’s hard to keep track of what they’re all up to. That’s why it was a little surprising to learn this week of an intriguing new result from a scientific spacecraft that’s been off my radar screen for some time.

The Reuven Ramaty High-Energy Solar Spectroscopic Imager &mdash called RHESSI, though it was just HESSI before being renamed to honor a pioneering solar physicist — rocketed into space on February 5, 2002. Since then it’s been scrutinizing the Sun’s face with X- and gamma-ray imagers, primarily to probe how energy is released and propagates during solar flares.

Apparently RHESSI has been moonlighting as a solar yardstick, measuring the Sun’s dimensions with unprecedented accuracy. Our star’s spin rate, once every 25.3 days at the equator, causes its midsection to bulge outward ever so slightly relative to its poles. The predicted value of this oblateness is 7.8 milli-arcseconds, about the apparent size of a dime in Boston as seen from San Francisco. It’s only about 0.0001% of the Sun’s diameter — not the sort of deviation that’s easy to detect, let alone measure.

Yet in this week’s Science Express, where Science trumpets articles before they appear in print, a quartet of researchers led by Martin Fivian (University of California, Berkeley) announced that the Sun is a little more oblate than predicted, a hair more than 8 milli-arcseconds. Moreover, when the team combined RHESSI’s measurements with those acquired previously, it found that the polar flattening becomes even more pronounced, by another 10.8 milli-arcseconds, during times of high solar activity.

These results might seem trivial, but solar physicists assure us they are not. The changing girth arises in magnetic ridges on the Sun’s surface that mimic, subtly, the texture of a cantaloupe’s skin. The deviation from a perfect sphere has implications for how the Sun pulls on Mercury, how the solar core is shaped, and perhaps how acoustic waves propagate throughout the solar interior.

Fortunately, the variable oblateness is far too inconsequential to affect predictions for the durations of solar eclipses — except for the most ardent purists. As diehard “umbraphile” Glenn Schneider points out, eclipse calculations usually consider the shape of the solar and lunar disks only to a precision of about 1 arcsecond, 50 to 100 times greater than what RHESSI measured.

If NASA had kept to its original schedule, astronauts would have made their fifth and final mission to service the Hubble Space Telescope back in August.

It's a good thing they didn't.

The space agency announced today that an onboard communication problem has temporarily shut down the World's Greatest Telescope — and postponed the planned house call in orbit, scheduled to begin October 14th, until no earlier than next February or perhaps April.

The failure occurred in the Command Unit Science Data Formatter, an electronics package that moves digitized streams of data from the science instruments to spacecraft's digital tape recorder for later playback to Earth. The CU/SDF has worked great for 18 years, so faulty craftsmanship isn't the issue. Nor is the venerable space observatory in any real trouble.

The good news is the that Hubble's designers included a second unit for redundancy. As far as engineers know, it still works — but it hasn't been checked since before HST's launch more than 18 years ago. Changing from one to the other is entirely doable but a lot more involved than just throwing a switch from "A" to "B". So Hubble's handlers are dusting off the owner's manual to begin the process; that might be completed by early next week, at which point the observatory will come back online.

More weighty, for the moment, is whether replacing the defective unit should be added to the already jam-packed "to do" list for astronauts on the forthcoming servicing mission, STS 125. A spare CU/SDF does exist at NASA's Goddard Space Flight Center (which manages Hubble's science payload) and could be made flight-ready soon.

During a hastily convened briefing for reporters today, Preston Burch, Hubble manager at NASA-Goddard, noted that replacing the 136-pound unit, which is roughly the size of a two-drawer filing cabinet, should be "a relatively straightforward activity" that would add only about 2 hours to one of the mission's five planned spacewalks.

It'll take a few months to certify that the spare is flightworthy, but NASA officials seem willing to accept that delay. This means the Space Shuttle Atlantis, already on the launch pad at the Kennedy Space Center in Florida, will be rolled back into its shelter. So will a second shuttle, Endeavour, that's standing by just in case a dramatic rescue of the Hubble repair team had been necessary.

As detailed in Sky & Telescope's October issue, the STS-125 crew hopes to install two scientific instruments (the Cosmic Origins Spectrograph and a replacement Advanced Camera for Surveys), repair a third, and swap in new batteries, gyroscopes, and other components. The spacewalkers will also attach a mechanism to allow the docking of a rocket stage at some future date for Hubble's safe disposal.

Should the replacement data formatter prove unfit to fly (considered unlikely), the repair mission will be hustled back to the launch pad as soon as it can — probably in November.

"Hubble has a habit of coming back from adversity," notes Edward Weiler, who heads NASA's Science Mission Directorate. "This particular failure was anticipated 20 years ago, and we have spare hardware ready to go."

I've always had a soft spot for an interplanetary pioneer called Ulysses. Built by the European Space Agency, it was launched in 1990 toward Jupiter, where the planet's powerful gravity yanked the craft out of the ecliptic plane and onto a looping path that carries it over and under the Sun every six years.

The initial mission concept, known as the International Solar Polar Mission, called for two identical craft — one European and one American — to study high-latitude regions of the Sun that can't be studied from Earth. But NASA reneged on its end of the deal, so Ulysses has soldiered on alone.

Recently it completed its third and final pass over the Sun's poles. That kind of longevity, far exceeding the planned 5-year-long mission, has really paid off. Ulysses's observations show that the solar wind is particularly feeble right now, with just 75% the strength it had a decade ago. In fact it's never been this weak since monitoring began a half century ago.

Space physicists had expected the flow to tail off, because the Sun's 11-year activity cycle is now at a minimum. But it's got far less punch than that seen during the last minimum. "The wind speed is almost the same, but the density and pressure are significantly lower," notes investigator David McComas (Southwest Research Institute), whose SWOOPS instrument aboard Ulysses has been key to the new finding.

The solar wind consists of plasma (ionized matter) and entrained solar magnetic field lines that pushed outward from the Sun's atmosphere into interplanetary space. Ulysses had previously shown that the wind comes off the Sun's poles faster and with less turbulence than it does from its midsection. But both the polar and equatorial flows have throttled back to historic lows.

There'd been earlier hints, in deep-space observations from IMP 8 and Voyager 2, that the solar wind variously ebbed and flowed during a solar cycle. Still, McComas and his colleagues, who detail their results in the September 18th issue of Geophysical Research Letters, don't know why the solar wind is taking a breather. One suspicion: perhaps the outflow is somehow being energized higher up in the Sun's corona, where there's less mass available to push outward into space.

In any case, the low flow means that the gigantic electromagnetic bubble that surrounds the Sun and planets must be shrinking inward and, with it, the solar system's boundary with interstellar space (called the heliopause). Both Voyager spacecraft are nearing this threshhold; they've aleady encountered a shock front inside the heliopause, and if this weak solar wind keeps up, Voyager 1 may find itself popping outside the heliosphere years sooner than expected.

Meanwhile, Ulysses itself is nearing the end of its historic mission. FLight controllers have been keeping a death watch all year, because the craft's source of heat and power (radioactive plutonium) has dwindled so much that the fuel lines are in imminent danger of freezing.

I contacted ESA project manager Richard Marsden for an update on the craft's health. "True to its name, Ulysses refuses to give up without a fight," he replied. "We're still getting science data, albeit only a few hours per day." The team has kept the fuel from freezing by firing thrusters every two hours. But the fuel is running low, and the team expects Ulysses to run dry sometime between the end of September and December. "With a bit of luck," Marsden adds, "we'll encounter the slow solar wind once again before then."

Hang in there, Ulysses!

Someone once said, "Opportunity knocks only once, but temptation bangs on your door for years." And ever since NASA plopped twin rovers onto the ruddy surface of Mars in early 2004, mission scientists have exploited the longevity of their mechanical marvels to explore ever-wider swaths of Martian real estate.

The rover Opportunity, in particular, recently wrapped up an entire year of scientific prospecting along the rocky inner slopes of Victoria crater — after rolling 4 miles (6 km) to get there. Measuring 2,400 feet across and about a tenth as deep, Victoria provided a ready-made "road cut" in the upper crust that allowed geologists to peer back into recent Martian history.

Now rover-meister Steven Squyres wants to dispatch Opportunity on an even more audacious undertaking: a 7-mile (12-km) trek to an even larger crater named Endeavour. It's about as far away as the entire distance that the rover has traveled to date, and the craft is already well past its 90-day warranty.

But reaching (or even nearing) 14-mile-wide Endeavour would provide a scientific boon, since the impact that created it undoubtedly unearthed countless rocks from deep crustal layers and lobbed them onto the surrounding terrain. Squyres also points out that heading south, toward that big pit, is where Opportunity would be heading next anyway.

The craft is in excellent shape, though there's a balky motor in the shoulder joint of its instrument-tipped robotic arm. And it'll have two advantages that should make the going easier. One is the eagle-eyed Mars Reconnaissance Orbiter, whose High Resolution Imaging Science Experiment (HiRISE) camera can record surface details smaller than the rover itself. The other is new onboard programming that helps the both rovers optimize their routes to avoid hazards such as sand dunes.

Still, Opportunity will have to hustle to reach Endeavour. Even clipping along at 110 yards per day, engineers estimate that the journey could take two years.

By the way, NASA's exploration of Mars was featured last week on National Public Radio's "Talk of the Nation: Science Friday." If you missed the broadcast, you can listen to streamed audio here.

On September 17th, the International Astronomical Union announced that an object in the Kuiper Belt — the fifth solar-system body large enough to qualify as a "dwarf planet" — had been named. It'll be called Haumea (pronounced how-MAY-uh), after the goddess of childbirth and fertility in Hawaiian mythology.

But there's far more to the story. When it comes to naming Kuiper Belt objects, the IAU typically accommodates whatever's suggested by the discoverer(s). In the case of Haumea, formerly designated 2003 EL₆₁ and now formally numbered minor planet 136108, there's debate — controversy, actually — over who discovered it.

Haumea is the name suggested by Michael Brown (Caltech), who together with Chad Trujillo and David Rabinowitz spotted it on December 28, 2004. But Brown didn't report his team's observations right away to the IAU's clearinghouse for such discoveries, the Minor Planet Center in Cambridge, Massachusetts, as he explains on his website. Instead, he and others continued to scrutinize this relatively bright and thus sizable body — learning a month later, for example, that it had a moon. (They eventually found a second moon as well.)

In July 2005, just as Brown was preparing to announce all this, Spanish astronomers Pablo Santos-Sanz and José Luis Ortiz Moreno sent the MPC some observations of the same object taken two years earlier at little-known Sierra Nevada Observatory. What's become clear since then is that the Spaniards accessed the American team's publicly accessible observing records 39 hours before submitting their discovery claim to the MPC but, they insist, after deducing the existence of 2003 EL₆₁ themselves.

To recap: Brown's team chanced upon the object first, but the Spanish observers reported its discovery first. There's still bad blood over this, and it's not likely to be resolved soon. For now, the MPC's record for asteroid 136108 lists "Sierra Nevada" as both the discoverer(s) and the discovery site, though those details are omitted from Haumea's official naming citation. But you won't find the discoverers' names listed next to Sierra Nevada (which is apparently how the Spaniards wanted it).

So why didn't 2003 EL₆₁ get christened Ataecina, the name suggested by Ortiz and his colleagues? Ataecina was a goddess worshiped by ancient inhabitants of the Iberian peninsula, and she was usually associated to Proserpina, Roman goddess of the underworld. Therein lies the problem: by IAU convention, deities of the underworld are reserved for objects in Pluto-like orbits (in resonance with Neptune), which 2003 EL₆₁ is not.

Brown's team proposed not only Haumea but also Hi'iaka and Namaka (two of Haumea's many children) for the two moons. It all fits together nicely.

But there's been plenty of behind-the-scenes rancor about how these names gained approval. Two groups, the Working Group for Planetary System Nomenclature and the Committee for Small-Body Nomenclature, were under pressure from IAU general secretary General Secretary Karel van der Hucht to resolve the 2003 EL₆₁ naming issue quickly. However, the CSBN's vote on Haumea ended in a tie or at best a slim majority, depending on who's doing the tallying (some of its members sit on the WGPSN as well).

Since the IAU wasn't bound to accept the name proposed by either team, one wonders why the WGPSN and CSBN didn't work harder to come up with something more politically neutral.

Oh, by the way, here's a question for any CSBN or WGPSN members who happen to read this: Is Ceres a dwarf planet? I know that was the IAU's intention when the controversial Pluto votes were cast back in 2006 — but unless I'm missing something, the approved resolutions never mention Ceres.

Discovering a planet around another star is no big deal these days — dozens of them have been reported in 2008 alone, and the total count now stands at more than 300.

Of course, the burgeoning exoplanet population hasn't stopped astronomers from looking for more of them. Big gaps remain in the sampling statistics, because the most successful techniques (radial-velocity monitoring, microlensing events, and periodic transits) favor finding large bodies close to their parent stars. Far-out planets are rarely discovered this way because they have long orbital periods and even longer odds of crossing directly in front of their stars.

But it should be possible to spot alien worlds directly by imaging very young nearby stars. This game plan assumes that any outlying gas-giant planets are still glowing warmly from having formed so recently, making them relatively easy pickings at infrared wavelengths. One of these came to light in 2004, though it orbits a feebly glowing brown dwarf rather than a proper star.

Now a trio of astronomers from the University of Toronto has found a "planetary-mass candidate" next to a young star that has roughly the Sun's mass. To see it, last April they utilized an adaptive-optics-aided infrared imager attached to the Gemini North telescope atop Mauna Kea in Hawaii.

The press release announcing the discovery touts the "First Picture of Likely Planet," but astronomers David Lafrenière, Ray Jayawardhana, and Marten van Kerkwijk are stopping short of calling it that.

For one thing, there's no information yet on the characteristics of its orbit — or, indeed, whether it's even bound to the star at all. They do know that it's not a star, because it's not very hot (about 1,800 kelvins, or 2,700°F) and its infrared spectrum reveals the presence of water and carbon monoxide. Most likely it's about 8 times the mass of Jupiter.

The parent star, which has the snappy designation 1RXS J160929.1-210524, lies about 500 light-years from Earth. So the putative planet's apparent separation of 2.2 arcseconds corresponds to about 330 astronomical units. That's already raised eyebrows among solar-system modelers, because it's highly unlikely that so massive a planet could have formed so far from its star.

The observing team has looked at more than 80 other stars in a 5-million-year-old grouping called the Upper Scorpius Association, and this is the only candidate planet they've turned up to date.

Jayawardhana admits that calling it a "planet" is a stretch; more likely, it's a "failed" binary star with a seriously stunted secondary. However, he notes that a massive planet might conceivably have formed closer in and then been tossed outward by a chance encounter with another large planet soon after the young star formed.

The true nature of 1RXS J160929.1-210524's companion probably won't become clear anytime soon. Its orbital period is likely thousands of years. At best, the team hopes to confirm that the star and its companion are moving together in space. "If we confirm that this object is indeed gravitationally tied to the star, it will be a major step forward," says Lafrenière. Those observations will have to wait until next spring, when the pair emerges from behind the Sun.

The observers have submitted their findings to Astrophysical Journal Letters for publication, but you can get a sneak peak in this online posting.