Tag Archives: Mercury

3 bright planets slow jam at dusk this week

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Jupiter, Venus and Mercury last night 35 minutes after sunset low in the northwestern sky. Details: 150mm lens at f/2.8, 1/30″, ISO 400. Photo: Bob King

Last night we finally cleared off after four solid days and nights of gray and rain. Sparkling low in the northwestern sky was a most welcome sight – Venus, Jupiter and Mercury. This week they will undergo to a series of remarkable gatherings in the early evening sky.

Venus leaped out immediately as the brightest of the trio. It stood 6 degrees above the horizon; that’s three fingers held horizontally at arm’s length. Jupiter jumped out next some 5 degrees to the upper left of Venus. Mercury, the dimmest of the the bunch, was very easy in binoculars but took a bit of concentration to see with the naked eye.

I’ve highlighted several nights of the triple planet gathering over the coming nights. Jupiter is colored yellow and Mercury pink to tell which is which. Created with Stellarium

This jam has just begun. Watch over the coming nights as the three planets move closer together to form a series of ever-changing jeweled triangles. Tomorrow night Mercury and Venus will be closest (1.4 degrees); Mercury and Jupiter on Memorial Day (2.3 degrees) and Venus and Jupiter on May 28 (1 degree).

All you need to see them is an unobstructed view to the west-northwest. You can begin your search about 30 minutes after sunset; get an early start because the planets set about an hour later. Binoculars can prove most helpful in case the sky’s hazy or if you have difficulty finding Mercury.

Left: If you could hover high above Earth’s north pole today and look down on the solar system, this is how the evening planets would be laid out. You can easily see how far they are from one another. At right, viewed from the flat plane of the solar system, they appear to bunch up. These occasional bunches caused by perspective are called conjunctions. Illustration: Bob King

As you can see from the nightly maps,  Mercury moves upward from the western horizon to join Venus, passes it and then teams up with Jupiter. Mercury moves rapidly because it orbits the sun most closely. Venus is also moving up from the west but more slowly, so it essentially stays in the same spot. Jupiter meanwhile drops down toward the western horizon. Earth’s motion around the sun is much faster than Jupiter’s causing the sun to literally “get in the way” between our two planets. From our perspective, Jupiter will soon disappear in the solar glare and won’t be seen again until early July when it reappears in the morning sky.

Although the trio may appear close to one another in the sky, they’re millions of miles from each other and the Earth. We see them together because they lie along the same line of sight for the coming week.

Watch as Venus, Jupiter and Mercury align after sunset

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The sky facing northwest this evening about 30-35 minutes after sundown. Venus and Jupiter should be relatively easy to spot provided you have an unobstructed view; Mercury might require binoculars. Stellarium

Hey, hey, hey. Three planets are now lining up in a neat row at dusk. Watch for the trio starting 30-35 minutes after sunset when they’ll be low in the northwestern sky.

The distance between Venus and Jupiter has shrunk over the past week and now stands at about 8 degrees or just shy of a fist held at arm’s length against the sky. Mercury finally joins the crew after emerging from the sun’s glare, though it will be the most challenging to see because of low elevation. As always when hunting planets in twilight, be a slacker and bring binoculars to make the job easy. Mercury will become easier to see by mid-week as it races up from the sun.

All three twilight planets appear close together near the sun in evening twilight is because they all lie in nearly the same line of sight (arrow) as seen from Earth. This view is a frame from a live orrery – click to watch the planets orbit the sun. Credit: dd.dynamicdiagrams.com

Venus is brightest at magnitude -3.4, while Jupiter and Mercury are near equals at -1.5 and -1.3 respectively. A week from now the three will all be clustered within a couple degrees of each other and form striking, triangle-shaped configurations that change night by night. I’ll have maps and times to look later this week. Get your cameras ready!

Mercury MESSENGER mission scores 100%

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Global maps of Mercury. Half the globe is shown in black & white, the other in color. Each map is composed of thousands of images. Click this and any of the other photos for hi-res versions. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Nice job MESSENGER! After two years in orbit, the entire planet of Mercury has been mapped. Can a cellphone map app be far behind? Prior to MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging), human eyes had seen less than half of the planet up close. No spacecraft had dropped by the solar system’s innermost planet since Mariner 10 sent us the first detailed images of Mercury during three brief flyby loops executed in 1974-75.

Craters (from left) Tolkien, Tryggvadottir and Chesterton are located close to the planet’s north pole and have permanently shadowed floors. MESSENGER found evidence for ice in all three. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Over the past two years the probe has taken more than 168,000 pictures of Mercury’s numerous craters, ridges and enigmatic “hollows”, mapped its topography and determined the makeup of minerals on its surface through examination of the light they reflect from the sun.The probe also revealed water ice coated with organic materials within permanently shadowed craters at the planet’s north pole.

The 20.5-mile-diameter crater Kertesz, named for photographer Andre Kertesz. Mercury craters are named for artists. Kertesz’s floor is pocked by enigmatic “hollows” which could be material boiled off by the sun’s heat and radiation. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

With the probe’s original mission extended from one to two years, it’s now coming to an end. Unless a further extension is approval, March 17 would be the last for data gathering. Principal investigator, Sean Solomon of Columbia University’s Lamont-Doherty Earth Observatory, has submitted a proposal that would keep MESSENGER and mission control in business for another two years, about the time it runs out of fuel and crash lands on Mercury.

Waters crater was recently named in honor of blues legend “Muddy Waters” (a.k.a. McKinley Morganfield). The “mud” pouring out below it is melted rock from the impact. A color image at upper right shows it’s appropriately blue-toned. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Keeping the mission running would let scientists continue targeted studies of various features and shoot photos at incredibly high resolution as MESSENGER’s decaying orbit carries it closer and closer to the surface. Not only that, but the spacecraft is ideally placed to study and photograph Comet ISON when it makes it grazes the sun later this fall.

An oblique view of a 174-mile-long escarpment cutting through a crater. The slope is a geologic fault resembling an “overbite” that formed when the planet shrunk due to cooling of its interior. The left side is 1.2 miles higher than the right. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

To celebrate MESSENGER’s milestone, I thought you’d enjoy a selection of images from recent photo shoots.We’ll know in April whether the mission will continue once a science commission makes its decision. Click HERE to browse more photos in the archive.

A closeup view of hollows in an unnamed crater. The pits almost always occur within or surrounding impact features. They’re about 100 feet to a couple miles wide and lack rims. Hollows might be volcanic vents or created when sulfur and other volatile materials escape from the surface during solar wind bombardment. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Return of the “Pink” Planet

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This map shows the sky from mid-northern latitudes facing west about a half hour after sunset tonight Feb. 12, 2013. Mercury lies about “two fists” below the moon in bright twilight. Fainter Mars is a few degrees below Mercury. Created with Stellarium

Don’t look now, but there’s a new planet creeping up from the western horizon. Mercury makes a special guest appearance at dusk for the next week or so. Tonight the moon can help you find this elusive planet. What makes it a hard catch? Well, it never strays far from the sun, appropriate behavior given that Mercury is, after all, the innermost of the eight planets. Typically it stands just two fists held at arm’s length above the horizon after sundown. If trees or buildings get in the way, you won’t even notice it.

Tonight it shines brighter than Rigil in Orion and nearly matches Canopus, the second brightest star in the entire sky. But you’d never know it. Trapped near the horizon, the little planet must compete against the orange glow of dusk and the greater thickness of air there.

Mercury (top) and fainter Mars shine together at dusk as seen from the Gulf of Trieste along the Adriatic Sea on Feb. 10, 2013. The photo nicely captures their naked eye appearance. Credit: Giorgio Rizzarelli

As we know from personal experience, the sun’s light is more tolerable near sunrise and sunset. Likewise, the rising moon is considerably fainter than one seen overhead. Dust and air molecules absorb and scatter light, especially when we direct our gaze horizon-ward where the air, water vapor and dust are thickest. Astronomers call this phenomenon atmospheric extinction. It’s the reason they wait for stars to get high enough to clear the thickest air before gathering data.

By the time Mercury becomes visible a half hour to 45 minutes after sunset, air and dust have dimmed it by more than a magnitude, making it similar to Betelgeuse in brightness. If all this talk of extinction makes you pessimistic about seeing the planet, I apologize. Mercury’s not hard to spot if you’ve got haze-free skies and an unobstructed western horizon. Don’t be afraid to cheat a little with binoculars. I sometimes use them to find a twilight planet early so I know better where to look once the sky gets darker.

Mercury photographed by NASA’s MESSENGER spacecraft. The generally gray globe is mostly blanketed by volcanic rocks. Credit: NASA

If you want a real twilight challenge, try finding Mars below Mercury. It’s not only fainter but being lower, even more of its light is sucked up by the air. Binoculars are essential for this one.

As a kid I always thought Mercury was a red-hued world and saw it that way whenever it would make one of its twilight appearances. Truth is, the planet is quite gray, much like Earth’s moon. Photographs from the MESSENGER spacecraft show a surface covered in ancient volcanic rocks. Only later did I realize that my pink planet gathered it color from the very twilight itself. What color does it look to you?

In darkness the moon is reborn

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If we could see the moon today, it would be a very thin crescent only a few degrees from the sun. Tomorrow it’s in new moon phase. Maps created with Stellarium

What’s old today but instantly becomes young again tomorrow? If you guessed the moon, you’re right! Today the moon winds up its current cycle of phases as an exceedingly thin crescent so close to the sun it’s invisible in the solar glare.

The moon’s cycle has always been a metaphor for life. Every month it’s born again as a thin crescent in the western evening sky, grows to a half-pie seven days later and reaches its full power and radiance when full at 14 days. After full, the moon’s radiance declines as its phase wanes to last quarter (21 days) and then to a whiskery crescent at dawn. Before it finally disappears in the sun’s glare, the moon, now 28 days old, reaches the end of its “life” cycle. But only briefly. The very next day, moments after new moon phase, it’s reborn again as an evening crescent.

When we run into troubles in our lives, we might look to the ever-renewing moon for inspiration.

The sky looking west-southwest a half hour after sunset Monday evening Feb. 11, 2013. You might be able to spot dimmer Mars in binoculars.

Tomorrow morning at 2:20 a.m. (CST) the moon will be exactly lined up with the sun and pass through new moon phase. Skywatchers in the western hemisphere won’t see the moon either day because it’s in the same direction as the sun and swamped by glare.

By Monday Feb. 11 however, the moon’s orbital motion will remove it far enough from the sun to be visible during evening twilight.  And there’s a bonus. The crescent will float a few degrees above the planet Mercury.

I’ve removed the atmosphere in this illustration so you can see where the moon is today at noon (CST), tomorrow morning when it reaches new moon phase and tomorrow Feb. 10 at noon. It passes north of the sun, which is in the constellation Capricornus. Notice all the planets in the neighborhood.

If we were to follow the moon today through new moon and into tomorrow, we’d notice it passes well north of the sun. Most of the time, the new moon is either north or south of the sun because its orbit is tipped about 5 degrees relative to Earth’s orbit.

The moon’s tilted orbit causes it to swing north or south (pictured here) of the sun from Earth’s perspective. A couple times a year however it crosses directly in front and a total solar eclipse is visible from somewhere on Earth. Illustration: Bob King

Over the course of its monthly cycle, it bobs up and then down along its tilted orbit. But 2 or 3 times a year, when the moon intersects the plane of Earth’s orbit at the same time as new moon phase, it crosses directly in front of the sun and we see a total solar eclipse. In fact, this is the only time we can see a new moon with the naked eye. It looks exactly like what you’d expect – a blank, black disk scrubbed free of its past life, waiting to begin the next as a tender crescent.

The new moon – black disk – is plainly visible silhouetting the sun during a total solar eclipse. Credit: Luc Viatour

Mercury and Mars twist it up at dusk

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Mars and Mercury have a quick tete-a-tete tonight Feb. 7 and Friday Feb. 8 low in the western sky in the direction of sunset. The scene shows the sky about 1/2 after sunset at which time Mercury will be about 8 degrees high. That’s just shy of one fist held at arm’s length against the sky. Created with Stellarium

It’s a long shot for some, but if you’ve got a wide open western horizon and clear sky tonight (Feb. 7) and tomorrow, you can watch a very close conjunction of Mercury and Mars. Mercury is just beginning its trek into the evening twilight, so it’s still low and soaked in solar glare. That will change next week when the planet climbs farther from the sun and becomes considerably easier to see.

Mars has been hanging around in twilight for months. Being on the faint side, it’s been a binoculars-only planet for many weeks. Mercury shines two magnitudes brighter at -1 and should just be visible with the naked eye in the darkening sky. Just the same, I’d bring binoculars if I were you. Scan a little ways above the west-southwest horizon about 30 minutes after sundown to locate Mercury. Once you see it, you’ll spot Mars about 3/4 degree (1.5 moon diameters) to its upper left tonight and 1/2 degree to its lower left Friday evening.

Good luck!

Bizarre green meteorite NWA 7325 may be from Mercury

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Wow, that’s what I call green! Green, glassy fusion crust coats one side of Ralew’s new meteorite. This is the largest of the 35 fragments, weighing just over 100g. Cube at right is 1 cm across. Click for larger version. Credit: Stefan Ralew

In April 2012 Stefan Ralew, a meteorite collector from Berlin, found himself staring at a spread of 35 green meteorite fragments for sale by a dealer in Morocco

“It was offered as a Martian (meteorite) but for me it was simply far too green,” said Ralew. Moroccan meteorite always keep an eye out for green rocks in the belief that they’re of Martian origin. Sometimes however they turn out to be nothing more than Earth rocks. Since this one was expensive, Ralew would have normally declined, but he noticed that the pieces had fusion crust, that frothy, typically dark coating of melted rock that forms when a meteorite is heated during its fall through the atmosphere.

Stefan Ralew Credit: Mirko Graul

“It was a big risk because of the high price,” said Ralew, but he sealed the deal and mailed off a piece to Dr. Tony Irving at the University of Washington, well-known for his expertise in meteorites from other planets.

After chemical analysis, Irving discovered that Ralew’s green rock was a completely new type of achrondrite (ay-KON-drite), a class of igneous meteorite that forms deep within the crust of larger asteroids and planet-sized bodies. In fact, Ralew’s green meteorite shared similarities with the planet Mercury, making it a one-of-a-kind.

Many of the more familiar achondrites that scientists and meteorite hunters have picked up here on Earth were blasted from the surface of Vesta by meteorite and asteroid impacts. Still others have been liberated from the moon and Mars. They drift through space until swept up by the ceaseless Earth. Scientists have done the math and arrived at the conclusion that meteorites from Mercury impacts should also by lying around in the deserts of the world, preserved by arid air and lack of rain. But no one had definitely identified a rock from Mercury until the green meteorite entered the scene.

A closeup of a polished, cut face of NWA 7325 shows striking green crystals of chromium diopside (a silicate mineral with chromium) and gray crystals of plagioclase, a rock also common in Earth’s crust. Click for larger version. There are a total of 345 grams (about 12 ounces) mostly in small fragments. Credit: Stephan Ralew

Other classes of achondrites called aubrites and angrites were once believed to have originated on the innermost planet, but further research points to their home on a yet-unknown asteroid or planet.

Mercury photographed by MESSENGER. The planet’s crust lacks iron and is pockmarked by countless craters. One of these impacts possibly sent NWA 7325 our way. Credit: NASA

Stefan’s meteorite, now classified as NWA 7325 (NWA=Northwest Africa, its find location), is a near-match for rocks examined from orbit by Mercury MESSENGER space probe. NWA 7325 is rich in magnesium, calcium and a silicate material laced with chromium that lends it an emerald sparkle, but it lacks iron. And that’s the key. Surface rocks on Mercury are likewise igneous and depleted in iron.

The match isn’t perfect. NWA 7325 has more calcium than it should and lacks the silicate mineral enstatite (common on Mercury), but that doesn’t worry scientists too much. Because the rock was excavated from deeper down in the crust, it would be expected to have its own unique qualities.

Mars meteorites show evidence of shock from impact in their crystal structures, and the same would be expected for rocks delivered to us from Mercury. Plagioclase, a very common mineral in Earth’s crust, and found in abundance in NWA 7325, has been completely melted, likely due to shock from the impact that sent it flying from the planet long ago.

Bubbly fusion crust on another fragment of Stefan’s meteorite. Click for larger version. Credit: Stefan Ralew

While the evidence points to a Mercury origin, we won’t really know for certain whether Ralew’s rock originated from the innermost planet until further studies are done. Scientists are still working to determinewhen those gorgeous green crystals formed as well as how long the rock coasted through space before arriving on Earth.

“Ultimately, only a sample return from Mercury may provide an answer,” wrote Irving in his group’s recent report on NWA 7325. In the meantime, Stefan’s meteorite stands as one of the most singular finds to date. It couldn’t have happened to a better guy. Ralew has a been a great friend of meteorite collectors and the scientific community for years. You can check out his website HERE.

More moon and morning planet alignments in store this weekend

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Mercury, Venus, Saturn and Spica alignment Thursday morning Dec. 6 from East Dayton, Ohio. Details: 17mm lens at f/8, 6-second exposure at ISO 400. Credit: John Chumack

Couldn’t get to Egypt to see the planets hovering over the Pyramids of Giza at dawn earlier this week? Cloudy skies or a work schedule that wouldn’t allow a dawn sashay?

Good news. You still have plenty of time to see some great planetary lineups. Unlike eclipses and some meteor showers, planet pairings can linger for days. While Mercury, Venus and Saturn may not be equally spaced as they were on Dec. 3, they still form a delightful connect-the-dots alignment along with the star Spica an hour before sunrise. With a visitation by the thinning crescent moon beginning tomorrow, you have all the ingredients for a series of special events worth a smidge of sleep loss.

The moon, planets and Spica tomorrow morning Dec. 8, 2012 facing southeast about an hour before sunrise. For many locations that’s around 6:30-7 a.m. The five worlds will span some 45 degrees of sky. Views created with Stellarium

Tomorrow’s garland-like arrangement of planets, star and moon is arguably more striking than Monday’s highly publicized alignment of Saturn, Venus and Mercury. Look at how nicely these celestial orbs are strung out across the dawn sky. To see them all, make sure you’re somewhere with a wide open view to the south-southeast.

There’s something for everybody in the dawn sky now through early next week as the moon “visits” each planet in turn while slimming to a slender crescent.

Then on the 9th, the moon passes little more than a degree (two moon diameters) south of Virgo’s brightest star Spica (SPY-kuh). Saturn will be 4 degrees north of the moon the following morning, and on Dec. 11, a pleasing thin crescent glides just a degree and a half south of Venus.

Enjoy these sights while you can. I hear the end of the world’s coming on Dec. 21. We’ll look at why that’s not likely to happen in a blog I’m hoping to write tomorrow. If there is a tomorrow …

Mercury, Venus and Saturn align in the morning sky

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Mercury, Venus and Saturn – along with Spica, which is similar to Saturn in brightness – will appear together in the southeastern sky at dawn. The maps show the scene about one hour before sunrise. Maps created with Stellarium

The upcoming Mercury-Venus-Saturn alignment, while not a real conjunction, is sure getting a lot of attention thanks to an inaccurate illustration on the Web depicting the three over the Pyramids of Giza. The planetary trio will be approximately equidistant and span an angle of 14 degrees (equal to 1 1/2 fists extended at arm’s length against the sky) on Monday morning Dec. 3. They’ll also appear in virtually the same lineup the mornings before and after.

When astronomers refer to a conjunction of two or more celestial bodies, they usually mean the objects are lined up closest together north-south of one another. When due south and highest in the sky, two planets in conjunction are stacked on top of each other. There are also conjunctions in longitude, when two celestial objects are closest together east-west or side-by-side.

Since none of the three planets is in conjunction, the Dec. 3 gathering is simply an interesting alignment. You’ll also notice from the diagram that for the next few mornings their configuration changes little. Tomorrow, Venus and Saturn will be a bit closer than Venus-Mercury; on Monday they’re equidistant and on Tuesday, Venus is closer to Mercury than Saturn.

The word planet comes from the Greek aster planetes or “wandering star”. And that’s exactly what they do. Ancient peoples thought they were carried around the Earth on invisible crystalline spheres. Today we know the truth – each orbits at a different distance from the sun with a period that depends on that distance. Mercury is closest and orbits fastest at 88 days; distant Neptune requires 165 years.

The ecliptic is the path followed by the planets, moon and sun across the sky. This narrow “highway” is a consequence of the planets orbiting the sun in nearly the same flat plane.

Planets are frequently in conjunction because they all follow the same path across the sky called the ecliptic.

It follows that if you’re all driving the same highway at different speeds, sooner or later two or more planets will pull up alongside each other. From our perspective, they’ll appear close together in the sky.

And since the planetary highway is approximately circular like a racetrack, interesting gatherings or conjunctions happen repeatedly over the months and years.

So if you combine the planets’ varying speeds according to distance, their shared “roadway” and our changing perspective on them as Earth revolves around the sun, you’ll understand why the current morning planet alignment will soon be broken.

Venus and the crescent moon about an hour before sunrise on Dec. 11.

No need to feel like you’re missing the opportunity of a lifetime though. Since these wandering stars are ever on the move, there’s an kaleidoscopic supply of conjunctions and alignments of every kind.

The really exciting ones usually involve the brightest planets or a planet-moon combo like the Jupiter-moon conjunction this past Wednesday.

Playing around with the free star-charting program Stellarium, I found that the next bright conjunction happens soon enough. On Dec. 11, the very thin crescent moon will be only 1.5 degrees south of Venus at dawn. It’s Christmas all year round when it comes to presents from the sky.

Curiosity’s history-making discovery a big misunderstanding

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Bite mark left in the sand dune after Curiosity retrieved soil sample. It’s similar to lava rock found in Hawaii and contains feldspar, pyroxene and olivine. Other materials found in the sample will be revealed next week. Credit: NASA/JPL-Caltech

Do you want the good news or bad news first? OK, the bad news. Remember when we learned last week that Curiosity had made a “history changing” discovery in a Martian soil sample? Many of us speculated that the rover had detected the first organic, carbon-containing compounds on Mars.

Well, it turns out it was just a big misunderstanding between the MPR reporter and Mars Science Laboratory (MSL) project scientist John Grotzinger. During the original interview, Grotzinger explained to reporter Joe Palca that Curiosity had analyzed the first soil sample in its Sample Analysis at Mars instrument. While SAM can detect organics, Grotzinger’s reference to the discovery being “one for the history books” was actually a reference to the entire Mars mission, not a specific finding.

Panoramic view of Curiosity’s digs at the Rocknest site in Gale Crater on Mars. One barren-looking landscape! The photo is a composite of images taken in October and November. Click to enlarge. Credit: NASA-JPL/Caltech

Somehow the NPR reporter misinterpreted the excitement surrounding the first soil analysis with Grotzinger’s description of the mission as history-making. Each thought the other was talking about a different thing. Indeed at the time of the interview, the first sample had only begun to be analyzed, so NASA scientists wouldn’t have even known the details of its chemical contents. Results, described as “interesting” rather than earth-shaking, will be presented next week at a meeting of the American Geophysical Union in San Francisco. More on the topic HERE.

Since it’s still very early in the mission, we shouldn’t be too bothered if some sort of Holy Grail moment has yet to happen. Look at what Curiosity’s found so far – an ancient stream bed filled with water-rounded cobbles, layered buttes of sedimentary rock like a postcard from the Grand Canyon and a most amazing assortment of wind-sculpted rocks. And don’t forget – we got there in the first place and Curiosity couldn’t be healthier.

Does anyone doubt that handfuls of history-making discoveries lie ahead? My only frustration is that NASA didn’t attempt to correct the misunderstanding sooner through one of its many press releases.

View of Mercury’s north pole seen from above. Red denotes areas of permanent shadow as seen by the MESSENGER probe to date. The polar ice deposits imaged by Earth-based radar are in yellow. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington/National Astronomy and Ionosphere Center, Arecibo Observatory

Now for the good news. Mercury, a planet with a surface temperature hot enough to melt lead has been confirmed by MESSENGER probe to have ice deposits in its polar regions. What the heck? Given that it’s the closest planet to the sun, you’d think it an unlikely place for ice, but the little planet’s axis is tipped less than one degree, so areas around its poles are never exposed to sunlight. Since Mercury has no substantial atmosphere to capture and distribute heat, its surface temperature ranges from 800 degrees F in sunlight to 200 below in the polar regions.

While radio-bright areas likely due to ice have been detected from Earth by the giant Arecibo radio telescope in Puerto Rico as long ago as 1991, new data from NASA’s orbiting MESSENGER spacecraft confirm that water ice is indeed present both exposed on the surface as well as buried beneath dark, tar-like deposits.

The probe uses neutron spectroscopy to measure hydrogen concentrations within Mercury’s radar-bright regions. Based on the amount of hydrogen seen, scientists can estimate the volume of water ice present, because water, or H2O, is two parts hydrogen.

“The new data indicate the water ice in Mercury’s polar regions, if spread over an area the size of Washington, D.C., would be more than 2 miles thick,” said David Lawrence, a MESSENGER participating scientist.

The dark material could be a mix of organic compounds delivered by carbon-rich comets and asteroids several billion years ago during the solar system’s youth. Astronomers believe that Earth was similarly enriched by water and organics. I like the connection, and I like that polar opposites – excuse the pun – find a home together on a most unlikely planet. To read more about the discovery, click HERE.