Moon and Jupiter with a side of JUICE, please

The waning gibbous moon lingers near Jupiter tonight and tomorrow night (Dec. 11) in the constellation Leo. This map shows the sky facing east around 11 p.m. local time. Source: Stellarium

Find the moon tonight and you’ll be led straight to Jupiter. Tomorrow night, too. Earth’s only satellite will spend the next two evenings wooing the largest planet which shines brightly to the west of Leo’s Sickle.

As Jupiter rises earlier and earlier, pushing higher into the evening sky, the European Space Agency’s JUpiter ICy moons Explorer Mission or JUICE recently got the green light to proceed to the next stage of development – working out the details of payload equipment and mission support among the many partners involved in the project.

JUICE will launch in 2022 and arrive at Jupiter in 2030 to begin a three-year-plus study of the giant planet and three of its largest moons – Ganymede, Callisto and Europa. The spacecraft will bristle with cameras, spectrometers, a radar, an altimeter, radio science experiments and sensors used to monitor the flow of charged particles (electrons, protons and others) in the Jovian system.

Artist impression of JUICE at Jupiter in the year 2030. JUICE will spend part of its mission in orbit around Ganymede, the moon at upper left. Credit: ESA/AOES

Scientists will explore Jupiter’s atmosphere, tenuous dust ring and its magnetosphere, a bubble of magnetism that enshrouds the planet similar to the one that funnels the solar wind into Earth’s upper atmosphere to spark auroras. No surpries – Jupiter has auroras, too.

JUICE will also investigate each of the three moons up close and their interactions with Jupiter, especially Ganymede. Detailed investigations Ganymede, the planet’s largest moon, will be performed when the probe enters into orbit around it – the first time any moon other than our own has been orbited by a spacecraft.

Europa, Ganymede and Callisto are all believed to hold oceans of liquid water beneath their frigid crusts. The mission will study the moons as potential habitats for life as it seeks to determine what conditions are required for planet and moon formation and the emergence of life.

This artist’s concept of Jupiter’s moon Ganymede, the largest moon in the solar system, illustrates the “club sandwich” model of its interior oceans. Credit: NASA/JPL-Caltech

JUICE will first visit Callisto, the most cratered object in the solar system, then fly by Europa twice, making measurements of the thickness of its icy crust. In 2032 the spacecraft will enter into orbit around Ganymede and study both its surface and internal structure including that possible hidden ocean.

“JUICE will give us better insight into how gas giants and their orbiting worlds form, and their potential for hosting life,” said Prof. Alvaro Gimenez Canete, ESA’s Director of Science and Robotic Exploration.

What? Two Full Moons this weekend?

A bright waxing gibbous moon dons a colorful corona as passing altocumulus clouds diffract its light earlier this week. Click photo to find the time of moonrise where you live. Credit: Bob King

Lovers of moonlight, this is your weekend. The moon’s essentially full two nights in a row. Full phase doesn’t occur until 6:27 a.m. (CST) tomorrow morning or midway between the two nights. That means tonight’s moon appears in the east about 12 hours before full, while an equally filled-out moon will shine just 12 hours after full Saturday night.

Only a sharp-eyed observer would notice a half-day’s difference in the moon’s phase, so for most of us, the moon will look full both nights. What’s more, it happens to be in one of the coolest places in the sky, smack in the middle of the Hyades star cluster not far from Taurus’ brightest star Aldebaran.

Tonight’s moon will appear in the middle of the V-shaped Hyades star cluster. At a distance of 153 light years, it’s the closest star cluster to the solar system. Stellarium

The moon’s brilliance will make the star cluster difficult to see with the naked eye, but binoculars will offer up a fabulous view of our satellite ensconced in Hyades like an ornament amid twinkling holiday lights.

You can also watch the moon glide eastward and approach Aldebaran during the hours before midnight. At 11 p.m. (CST), they’ll be just 1.4° apart.

Aldebaran is more than twice as close to Earth as the Hyades; it hovers in the foreground and is unrelated to the cluster. Looking up tonight, our gaze will plumb all three dimensions of the sky in a single glance – from the relatively closeness of the moon to the middle distance of Aldebaran and further to the more distant Hyades.

Happy nights adrift on the Moon’s Sea of Showers

Over 700 miles across, Mare Imbrium (Sea of Rains) is the largest lunar sea. Its roughly circular shape is defined by a series of mountains ranges just coming into good view tonight and the next few nights. Credit: Joseph Brimacombe

If you’re looking for a great little place to point a small telescope the next few nights, let me suggest Mare Imbrium, the largest of the lunar “seas”. That’s Latin for Sea of Showers or Sea or Rains. Lovely name. The last time it rained there was never.

Wide view of the whole Moon with the Imbrium basin circled. While Imbrium is the largest lava-filled “sea”, the largest basin, the South Pole-Aitkin Basin, is 1,600 miles in diameter. Credit: Silvercat/Wikipedia

All the Moon’s seas are enormous basins excavated by asteroid impacts between 3.1 and 4.2 billion years ago. Cracks and fissures in the Moon’s crust from the collisions served as conduits for deeper lava to rise and fill the basins with molten rock. These great pools cooled and solidified, forming the large grey spots that make up the face of the Man in the Moon that even a child notices today.

Ruptures in the Moon’s crust caused by the impact of large meteorites/asteroids creates what astronomers call multi-ringed basins. They look like bulleyes, a fitting comparison under the circumstances. Credit: Steven Dutch

Many of the seas are ringed by mountain ranges formed by faulting of the lunar crust during the impacts aided by slumping of material off the fresh slopes.

Earth’s mountains in contrast are lifted up when tectonic plates collide or pile up during volcanic eruptions.

Three ranges shape the outer boundary of the Sea of Rains – the Carpathians, the majestic Apennines and Caucasus. The Alps form part of a second inner ring of peaks. Each is named for its sibling range in Europe. Over the next few nights we’ll see all four cast awesome shadows as the Sun rises over their craggy peaks.

This is how our featured region of the Moon will appear tonight from the Americas. Mountain ranges are labeled in black, craters in white. Credit: Virtual Moon Atlas / Patrick Chevalley and Christian Legrande

Tonight features the Alps, Apennines and Caucasus and the spectacular craters Plato and Copernicus. Tomorrow night, the Carpathians, north of Copernicus, come into view. The reason these features look most dramatic now rather than closer to full Moon is because the terminator cuts across the region. Along the terminator, the boundary separating lunar day from night, the Sun is just rising and every little peak casts a shadow.

The Apennines Mountains is host to the Moon’s tallest mountain, Mt. Huygens, with an elevation of 18,046 feet (5.5 km). Credit: M. Galfalk, G. Olofsson, and H.-G. Floren; SIRCA camera Nordic Optical Telescope with annotation by the author

While binoculars will reveal Plato, Copernicus and the mountain rings, a small telescope will show the scene best. I wish you a clear and not-too-cold night!

The Moon, still young after all these years / See a Callisto eclipse!

The Moon and Mars gather in the west at dusk this evening. Stellarium

Tonight the returning young crescent Moon puts down stakes near the planet Mars in Sagittarius. Look for the pair low in the southwestern sky at dusk.

We’re used to hearing how ancient the Moon is. Its origin goes back to 4.48 billion years ago when a Mars-sized planet sideswiped the Earth, blasting debris into space that quickly coalesced into our satellite. While it’s true that most of the Moon’s crust and craters date from then, recent close-up photos from NASA’s Lunar Reconnaissance Orbiter (LRO) suggest the Moon remained volcanically active until not that very long ago. At least on geological time scales.

Ina Caldera, a classic IMP, sits atop a low, broad volcanic dome or shield volcano, where lava once oozed from the moon’s crust. The darker patches in the photo are blobs of older lunar crust. They  form a series of low mounds higher than the younger, jumbled terrain around them. Credit: NASA

100 million years ago, when dinosaurs cracked jokes about the early mammals, lava oozed from cracks in the Moon’s crust to create what astronomers nowadays call IMPs or Irregular Mare Patches. They’re characterized by a mixture of smooth, shallow mounds next to patches of rough, blocky terrain. Only one, called Ina, is large enough to see in amateur telescopes. The others, liberally sprinkled across the lunar nearside, are generally less than 1/3 mile (500 m) across. Using the LRO, a team of researchers led by Sarah Braden of Arizona State University has found 70 landscapes similar to Ina.

When it comes to the big picture, 100 million years is a small slice of Earth’s history. Credit: NASA

Maria (plural of “mare”) are those big dark spots the make up the face of the man in the moon. They’re actually huge expanses of lava that welled up from cracks in the Moon’s crust several billion years ago after asteroid impacts. IMPs are much more recent. Some may be as “young” as 50 million years old. This was well after the dinosaurs succumbed to major climate changes induced by the impact of a 6-mile-wide asteroid hit here on Earth. Now the mammals are cracking jokes about the dinos.

A selection of some of the 70 IMPs discovered during the survey. Credit: NASA

“Discovering new features on the lunar surface was thrilling!” says Braden. “We looked at hundreds of high-resolution images, and when I found a new IMP it was always the highlight of my day.”

Astronomers determine ages of lunar features by doing crater counts. The more lightly cratered an area is, the younger.

Here’s the scene tomorrow morning November 26th with all four of Jupiter’s bright moons. Callisto, which sits right next to Europa, will dramatically fade over several minutes time starting about 4:50 a.m. CST. Meanwhile, 15 minutes later at 5:05 a.m., Ganymede will exit its eclipse and return to view. Add one hour for EST, subtract an hour for MST and two hours for PDT. South is up. Stellarium

Some of you may be early morning observers. Well, I’ve got a special event to share with you. Tomorrow morning November 26th, Jupiter’s bright moon Callisto will be eclipsed by Jupiter’s shadow starting at 4:50 a.m. (CST) and disappear for nearly five hours.

Just 15 minutes after Callisto disappears, Ganymede emerges from eclipse at 5:05 a.m. (CST). One disappears, the other reappears. Pretty cool! Jupiter will be the brightest thing in the sky high in the south in Leo at the time. You can always find out what Jupiter’s moons anytime of day or night by visiting Sky and Telescope’s Jupiter’s Moons site.

Winter got you down already? Sample spring and a lovely conjunction at dawn

The crescent Moon, just a few days before new, sits atop Virgo’s brightest star, Spica tomorrow morning at dawn. This map shows the sky facing southeast about 50 minutes before sunrise. Stellarium

November nights are long, long, long. You can start the evening with the Summer Triangle, catch wintery Orion at midnight and by dawn it’s already spring! Celestially speaking anyway. Here at 47 degrees north latitude in Duluth, Minn. night takes up the lion’s share of the day with nearly 15 hours of the dark stuff between sunset and sunrise.

If winter’s already nudging into your comfort zone, why not head outside tomorrow morning for a dose of spring stars and a beautiful conjunction of the crescent Moon and Virgo’s brightest luminary, Spica? You can see them even earlier than the map shows when the sky is still dark.

The Moon, just 3 days before new phase, resides in the springtime constellation Virgo. Not far off you’ll also see the little trapezoid of Corvus the Crow. Higher up to the left or north, sparkling Arcturus sputters and twinkles in the cold air.

You can’t stop the Earth from rotating. Once the Sun’s well up in the east, the early summer stars come into view, or they would, if there was no atmosphere. They’re there alright but hidden by scattered sunlight that colors the sky blue. By mid-day, summer’s in full swing. Come sunset, the cycle repeats itself again. And that’s how we roll.

Guess who’s up before midnight? By Jove, it’s Jupiter!

Brilliant Jupiter now rises in the northeastern sky before midnight. The waning gibbous Moon will join the planet Thursday November 13th. This map shows the sky facing east at midnight in mid-November. Stellarium

If the sky’s seemed devoid of evening planets of late, you’re right. Mars still hangs on in Sagittarius, but it’s so low and sets so early, few notice. Most telescopic observers have long since abandoned the planet. With an apparent diameter of three-one-thousandth’s that of the Moon, it’s just too tiny to eke out any details.

Venus is also “officially” an evening planet but still much too close the Sun to view. Enter Jupiter. This jolly bright planet joins the evening crew with a bright flourish, rising in Leo the Lion. In the days of Daylight Saving Time it rose around 1 a.m. but now catches our eyes a little before midnight low in the northeastern sky.

Jolly Jove on November 8, 2014. The two big stripes are the North (top) and South Equatorial Belts. The Great Red Spot is seen along with a cluster of smaller oval storms. Credit: Christopher Go

Earth’s revolution around the Sun causes the stars and planets in the eastern sky to rise 4 minutes earlier each evening, while those in the west set 4 minutes earlier. Over time, stars in the west get pushed out of the way as those in the east rise higher and take over the sky. It’s the astronomical equivalent of seeing each older generation swept away by the little babes whose job it is to replace us.

My point is that Jupiter, while low now, will rise an hour earlier by Thanksgiving  (16 nights x 4 mins. = 64 minutes) and nearly 3 hours earlier by Christmas. We’re soon to see a lot more of this planet. So goes the cycle of the sky.

Three of Jupiter’s four bright moons will be visible in small telescopes tonight. This view shows them around midnight (CST) tonight. North is up. Stellarium

Not only is Jupiter a pleasure to see with the naked eye – it’s so darn bright – but its dynamic weather and four bright moons offer telescope users something new to see every time we look through the eyepiece.

Because Jupiter’s 11 times larger than Earth, it presents a huge disk compared to most planets. Even with a 3-inch scope you can watch the moons shuttle back and forth and spy the largest clouds belts. The Great Red Spot, an enormous hurricane-like storm, has been shrinking over the last decade but can still be spotted in 6-inch and larger instruments.

The 2014-2015 apparition of Jupiter is special because Earth crosses through the planet’s orbital plane. Since the four brightest moons orbit almost exactly around Jupiter’s equator, we’ll get to see them eclipse and occult one another. Eclipses are especially interesting to watch – over a few minutes time you can actually watch a moon temporarily fade away. I’ll have more on these fascinating events soon.

Aurora alert tonight through Monday night Nov. 9-10

Aurora smolders beneath the Big Dipper tonight November 9th around 7 p.m. Credit: Bob King

Around 7 p.m. this evening, just before moonrise, a smoky green glow fired up beneath the Big Dipper low in the northern sky. The Moon rose and clouds soon followed, but we might be in for a couple nights of northern lights.

Cirrostratus clouds at moonrise this evening refracted moonlight into a pretty halo. Caught in the semi-circle is the Hyades star cluster (lower right). The Pleiades are at upper right. Credit: Bob King

A coronal mass ejection that launched from the Sun on November 7th will arrive overnight and could produce minor to moderate (G1-G2) geomagnetic storms now through midnight Monday night. The strongest activity is expected between 3-9 a.m. (CST) tomorrow morning.

A blast of high-speed electrons and protons from the Sun on November 7 looks like it may affect Earth overnight and into Monday. Credit: NASA/ESA

Tonight’s little taste will hopefully be a sign of more to come.

Will the Full Frosty Moon give you the shivers?

The Full Moon returns to an eastern horizon near you tomorrow evening. Click to find your moonrise time. Credit: Bob King

November’s the last month that still carries a connection to fall. Once December arrives, there’s no going back. Tomorrow at 4:23 p.m. (CST) the Full Beaver or Frosty Moon will rise near sunset and stay up all night.

This month we notice how much higher the Full Moon is than during the summer months. Why is that? Think where the Sun is right now. Have you noticed how much lower in the sky it is compared to June and July?  As our star hunkers down to its winter lair in Sagittarius, the Full Moon, directly opposite the Sun in the sky, moves into Taurus and Gemini. These are the very constellations the Sun occupies during the summer months when it blazes nearly overhead and cooks skin red if we’re not careful.

The Full Moon rises in the northeastern sky near the border of the constellations Cetus and Taurus. Taurus is one of the zodiac constellations and features the famous Pleiades star cluster about a fist to the right of the Moon. Stellarium

You needn’t worry about a moonburn. Although the Moon shines by reflected sunlight, it’s a dusty mirror covered in cobwebs. For all it takes in, our satellite delivers only 12% of the light back. Brilliant to the eye, it’s more than 165,000 times fainter than sunny Sol.

But as the Sun abandons us, Luna comes to the rescue. Despite its wimpy reflectivity, it’s the brightest object in the night sky. Once we allow our eyes to adapt to the dark, the Full Moon provides more than enough light to see our way around, pick out details of the landscape and even sense color. This is especially true now through early spring when the Moon climbs high in the sky where absorption of light by our atmosphere is least.

Clear November nights usually mean frost as the dew point drops below freezing. Don’t be surprised to see tomorrow night’s Full Moon illuminating your lawn as if it were a plush white carpet. Illustration: Bob King

From the countryside I’ve distinguished green leaves, the red of stop signs and other colors though they’re muted and occasionally take some convincing.

The quality of moonlight fascinates. Shadows are summertime short but black and stark. Contrasts are accentuated. A patch of dark behind a rock becomes a lurking animal. There’s just enough light to get around but not enough to provide the information we need to contain our imaginations. But hey, that’s half the fun.

Light passing through the eye’s lens and adjustable iris stimulates rod and cone cells the retina allowing us to see both at day and night.

Our retinas are equipped with two types of cells that respond to light — cones and rods. Cone cells, which are concentrated in the center of our visual field, are very good at color vision and detecting fine detail but only work well in bright light.

Rods are very sensitive to low light but not sensitive to color. We use them for night vision, peripheral vision and detecting fine motion. Because our “high-def” cone cells aren’t active in low light, the rod cells take over. While they’re great in moonlight, our vision lacks the kind of definition provided by the cones. Everything looks grainy at night like pictures shot at high ISO.

Like the other animals with whom we share the planet, we’re creatures of Earth’s day-night cycle; our vision has evolved to accommodate both brilliant sunlight and the tepid light of night.

Earth and Moon captured together in amazing new photo

Chang’e 5 took this splendid photo of Earth and Moon together while it passed over the lunar far side on October 28, 2014. The Moon reflects far less light than Earth and appears darker.  Click to grab a large version. Credit: CNSA / Xinhua News Agency

A friend alerted me to this wonderful photo of Earth and Moon in the same single image taken by China’s Chang’e 5 lunar test vehicle. The spacecraft is conducting an 8-day mission to the Moon and back to refine the technology needed for a planned sample return mission in 2017. Launched on October 23, this is China’s fourth volley to the Moon; the spacecraft will return to Earth on November 1 according to Xinhua News.

View of Earth taken by the Chang’e 5 test vehicle on October 28 after rounding the far side of the Moon. Australia is easy to see in the clearing. Credit: CNSA / Xinhua News Agency

As it swung high above the far side of the Moon – the hidden half of the lunar globe out of sight from Earth – the solar array monitoring camera on the craft snapped this incredible image. While not the first ever taken of the pair, it’s one of the best composed images and possibly the first to clearly feature the lunar far side along with Earth. You can easily see how much more cratered the Moon’s hidden hemisphere is. And that dark splotch? That’s Mare Moscoviense (Sea of Moscow), one of the very few dark maria or seas on the far side.

View of the Moon by Chang’e 5 on October 28 shows the dark lunar “sea” called Mare Marginis. This patch is visible along the western edge of the moon from Earth. Credit: CNSA / Xinhua News Agency

Chang’e 5 did not enter lunar orbit but kept its camera humming to shoot separate close-ups of Earth and Moon. Like seeing Earth and Moon from afar? Check these out:

Earth and Moon dance a pirouette in these images taken by the Jupiter-bound spacecraft Juno on Oct. 9, 2013

The European Space Agency’s Mars Express captured this image of Earth and the Moon on July 3, 2005 when it was 5 million miles ( 8 million km) away. Credit: ESA

Earth and Moon in 1992 as Galileo photographed the duo on its way to Jupiter. Credit: NASA

Earth is the brightest “star” in Mars’ western evening sky as seen and photographed by the Curiosity Rover on Jan. 31, 2014. Credit: NASA

A single frame from high-definition video of the full Earth over the lunar limb taken by Japan’s Kaguya spacecraft on April 6, 2008. Credit: JAXA/NHK

Earth and Moon from Mars, imaged by Mars Global Surveyor on May 8, 2003. Credit: NASA

Earth rises over the barren lunar landscape photographed by the Apollo 8 crew on December 24, 1968. Credit: NASA

Earth and Moon become a single dot in this photo taken by the Voyager 1 spacecraft from a distance of 4 billion miles (6.4 billion km) on February 14, 1990. Credit: NASA/JPL

Found! Fresh moon crater from LADEE spacecraft impact

Before and after photos show the new crater blasted out by the impact of the LADEE spacecraft. It’s the white spot a short distance to the upper right of the prominent crater in the center and measures less than 10 feet (3-m) across.  Credit: NASA/Goddard/Arizona State University

I’d love to see that ad on Craigslist. Using before and after photos taken by NASA’s Lunar Reconnaissance Orbiter Camera (LROC), Mark Robinson, LROC principal investigator, discovered a tiny crater within one-fifth of a mile (300-m) of the predicted impact zone. And I do mean tiny. The impact of the refrigerator-sized spacecraft at the relatively leisurely speed of 3,800 miles an hour (1,699 meters per second) excavated a hole under 10 feet across or as big as your bathroom.

LRO close up photo of the LADEE impact site on the eastern rim of Sundman V crater. The bright area highlights what has changed between the time of the two images, specifically the impact point and the ejecta. The ejecta pattern spreads to the northwest, consistent with the direction the spacecraft was traveling when it smacked into the surface. Credit: NASA/Goddard/Arizona State University

NASA’s LADEE or Lunar Atmosphere and Dust Explorer’s mission studied dust hovering in the Moon’s extremely rarefied atmosphere called the exosphere. Much of the dust sputters off the surface during meteorite impacts, but some may be lofted into the sky by electrostatic forces active when the sun rises along the day-night borderline called the terminator. As the probe used up the last of its fuel, engineers lowered its orbit to study the lunar environment in ever greater detail. Variations in lunar topography and gravity soon brought it crashing to the surface on April 17 this year on the farside of the Moon.

LADEE only had so much fuel to conduct operations at the moon. When that was used up, the mission was complete. The vending-machine-sized probe broke apart as it heated up upon impact. Credit: NASA Ames/Dana Berry

The small size of the LADEE crater relates to the relatively slow impact speed (meteorites strike at a much higher velocity) as well as the craft’s small size and low density. To find it, investigators had to develop special software that compared before and after images to find the slightest changes between them. The impact popped into view much the same way before and after images of the sky are compared to detect moving asteroids.

Despite the crater’s tiny dimension, the crashing spacecraft managed to eject a plume of bright lunar dust 656-984 feet (200-300 meters) from the impact site. Future astronauts will likely find metal shrapnel from the probe mingled with lunar dust downstream from the impact.

“I’m happy that the LROC team was able to confirm the LADEE impact point,” said Butler Hine, LADEE project manager at Ames Research Center in California. “It really helps the LADEE team to get closure and know exactly where the product of their hard work wound up.”

In a memorable mess of an impact that will remain visible for millions of years.