Tag Archives: moon

Evening moon, popular planets and extreme sports on Mars

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Face west-northwest tonight to see the moon near the star Regulus as well as a tight group of four bright sky objects – two stars an two planets. Created with Stellarium

The ambling moon is one day shy of first quarter phase tonight and lights up the sky near the star Regulus in Leo the Lion. Closer to the horizon, Venus and Mercury couple up with Gemini’s brightest stars Pollux and Castor, with bright Capella glimmering alone in the north.

Mercury and Venus join up for a conjunction (close pairing) on the 19th and 20th, while the moon passes near Saturn on June 18-19. Mars and Jupiter are both too close to the sun to see, but will soon return to morning twilight in the next several weeks.

A recent image from the Mars Odyssey spacecraft showing dark-bordered streaks caused by winds blowing around the dual craters’ walls. The dark areas are scoured of surface dust; the light zones are where the winds deposited their load of dust after being braked by the craters’ walls. Credit: NASA/JPL/ASU

Speaking of Mars, I came across some great images recently of wind streaks and dry ice “snowboard” trails on the Red Planet. Wind streaks can appear either dark or light-colored on Mars. When strong winds converge around craters and cliffs they can sweep away the lighter surface dust exposing the darker lava plains beneath. Craters can also slow down the winds, causing them to drop their loads of dust as light-colored streaks on the obstacle’s lee side. Sometimes both happen at the same time as in the photo above.

Mars Reconnaissance Orbiter photo of “linear gullies,” which may be explained by slabs of dry ice gliding down the slopes of sand dunes.  Different in form from other streaks and gullies on Mars, they can extend up to a mile (2 km) and end abruptly in pits.  Scale in meters at left. Click to enlarge. Credit: NASA/JPL-Caltech/Univ. of Arizona

While wind streaks make sense because of their earthly analogs, dry ice chunks gliding down the slopes of sand dunes on cushions of their own vaporizing gas sounds distinctly more alien. Yet that’s what NASA researchers believe is happening to create the zillions of narrow furrows seen along the slopes of some Martian sand dunes.

“I have always dreamed of going to Mars,” said Serina Diniega, a planetary scientist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and lead author of a report published online by the journal Icarus. “Now I dream of snowboarding down a Martian sand dune on a block of dry ice.”


Dry ice gliding on sand dunes 

Carbon dioxide frost coats the dunes during the Martian winter which lasts about twice as long one on Earth. Over time, the ice accumulates and gets compressed into slabs which can break off and glide downhill during the spring season. As frozen carbon dioxide (dry ice) changes directly from a solid to a gas on contact with the warmer sand, the gas pushes against the surface to create a cushion of air. The block rides the cushion all the way to the bottom where it continues to vaporize, forming a little pit at the end of the gully. Be sure to watch the short video – I think you’ll be delighted at the experiment using dry ice on sand dunes here on Earth.

Lunar peaks may be spattered with exotic asteroid fragments

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Olivine and spinel have been found in the central peaks of the 58-mile-wide lunar crater Copernicus. See closeup photo below. Credit: Paolo R. Lazzarotti

Minerals seen in some of the moon’s craters may not belong to the moon at all but instead were likely delivered by asteroids or possibly even the Earth. Unusual minerals like spinel (ruby-like red gemstone) and olivine (olivine-green gemstone) have been found on the floors and especially in the central peaks of several larger lunar craters including the familiar Tycho, Copernicus and Theophilus using instruments like NASA’s Moon Mineralogy Mapper. Scientists assumed they were seeing material excavated from deep below the moon’s surface.

A bird’s eye view of some of the Copernican mountain peaks photographed by the Lunar Reconnaissance Orbiter. Peaks form during rebound of the crater’s floor after impact. Copernicus is about 900 million years old. Click to enlarge. Credit: NASA

Maybe not. These very same minerals are also common in meteorites. A recently published study in the journal Nature Geoscience by a team of scientists from the U.S. and China used computer models to fling simulated asteroids and meteorites at the moon with speeds under 26,820 mph (43,160 kph). Some 30% of asteroidal debris striking the moon travels below that speed according to the study.

Tycho, one of the most prominent craters on the moon, is 51 miles (82 km) across and formed when a small asteroid struck the moon relatively recently – only 110 million years ago. Like Copernicus, olivine has been found atop its central peak. Credit: William Wiethoff

When these slower-moving space rocks slam into the moon, the researchers found that fragments survived the impact. If the newly formed crater was 12 miles (20 km) wide or larger, asteroid material sent flying outward toward the crater’s rim would later fall back through gravity into the crater’s central peak. Peaks form in big craters when material that’s crushed and compacted by the incoming asteroid rebounds or rises back up in the crater’s center after impact.

An LRO photograph of Tycho’s 1.2-mile-high (2 km) central peak. The mountain complex measures 9.3 miles (15 km) from side to side. Resting near the summit is a large boulder 400 feet (120 m) wide. Click to enlarge. Credit: NASA Goddard/Arizona State University

“This observation may explain recent observations of exotic Mg-rich spinels and olivine in the central peaks of craters too small to have excavated the deep crust or mantle of the Moon,” they wrote. By extension, the team suggests that crater peaks on Mars and Vesta may also preserve remnants of exotic minerals delivered by asteroids.

A tighter view of the boulder in the photo above. The scene is 3/4 mile (1.2 km) wide. How such a large object ended up intact atop a mountain isn’t know for certain, but it probably rolled out of the impact debris forming the rising summit. Click to enlarge. Credit: NASA Goddard/Arizona State University

It’s generally assumed meteorites vaporize upon impact and leave only tiny fragments in crater floors, but if the impactor moves below a critical speed, the results of the study show it can leave bigger pieces. That means scientists must be cautious when deciding if the rock in the moon’s peaks really do represent samples excavated from deep down in the moon’s mantle or whether they’re alien rocks left by potshot asteroids.

Steps in the formation of a crater’s central peak. Small impact make simple, bowl-shaped craters; larger ones have peaks. Credit: JAXA

More intriguing is the possibility that some of those olivines and other exotic minerals came from Earth. Our planet got whacked as much or more than the moon several billion years back. More than 170 named lunar meteorites have been found on Earth, and studies have shown that delivery of “Earth meteorites” to the moon via impact is easily accomplished. You never know – there may even be the hardened, glassy remains of stromatolites, one of the planet’s earliest life forms dating from as early as 3.5 billion years ago, sparkling atop some lunar mountain. In simulations, materials leaving Earth would have melted on the outside but remained intact within.

Cool moon, hot sun and a laser-like PANSTARRS comet

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Click to watch the nearly full moon cover the bright star Beta Scopii last night.

I caught a glimpse of the moon last night but clouds ruled soon after. Too bad. Like some of you I’d hoped to see the bright star Beta in the constellation Scorpius pinned to the moon’s edge. Others were luckier including Dave Dickinson, who watched the event from Hudson, Florida. You can watch the moon slowly edge up to the star and cover it in his video above. All these broiling and boiling you see along the moon’s edge is due to air turbulence.

The sun photographed this morning at 10:15 a.m CDT by the Solar Dynamics Observatory. Sunspot groups 1755 and 1756 are magnetically complex and could produce moderately powerful M-class flares. The groups are approaching the center of the sun’s disk, a great place to let loose with flares that could lead to auroral displays on Earth. Credit: NASA

Billows of high-speed particles shot out during from recent solar flares arrived yesterday afternoon (U.S. time) and overnight. Any auroras that might have been visible had to compete with moonlight in northern European skies and again this morning around 1-2 a.m. Central time here in the northern U.S. and Canada. There remains a 20% chance for a minor auroras for mid-latitudes tonight.

Comet C/2011 L4 PANSTARRS on May 23 displays a long, “laser beam” tail due to our unique perspective on the comet. Click to enlarge. Credit: Michael Jaeger

By Monday night (May 27), the moon will be out of the sky for at least a little while at nightfall. During this  dark window I encourage sky watchers with 50mm or larger binoculars or a telescope to point it toward Comet PANSTARRS, the comet that keeps on giving. Earth passes through PANSTARRS’ orbital plane Sunday-Monday affording us a unique perspective.

From our perspective on Earth we view the dust boiled off from Comet PANSTARRS’ nucleus edge-on this weekend. It all stacks up to create a very narrow, long and relatively bright tail. Seen broadside, it would appear as a wide, faint fan. Illustration: NASA with additions by Bob King

Normally we look at comets off to one side or another and see the dust left behind in its orbit as a broad glowing fan or fan-shaped tail. This weekend however we’ll face PANSTARRS’ debris edge-on. All the dust spewed in the past few months lines up one particle in front of the other to create a thin streak of a tail many degrees long. The photo shows the effect beautifully. You can read more about Earth and PANSTARRS in my article in Universe Today. Click HERE for a map to find the comet.

 

Meteoroid hits moon, goes boom!

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Bright impact flash made by a 1-foot-wide rock that struck the moon on March 17, 2013. The moon was a crescent in the evening sky at the time. The impact occurred in the dark, earthlit part of the moon away from the sun-lit crescent. To see video, click photo and then click again to open video after download. Credit: NASA

Anyone looking at the moon at the right time on St. Patrick’s Day with a small telescope would have seen it. A pinpoint flash of light as bright as a 4th magnitude star suddenly appeared that evening in the lunar sea Mare Imbrium and faded away one second later.

The St. Pat’s Day meteoroid strike occurred near the prominent crater Copernicus in Mare Imbrium, the Sea of Showers. Photo: Bob King

“On March 17, 2013, an object about the size of a small boulder hit the lunar surface in Mare Imbrium,” says Bill Cooke of NASA’s Meteoroid Environment Office. “It exploded in a flash nearly 10 times as bright as anything we’ve ever seen before.”

Frames in false color taken from the original black and white video show the explosion in progress. Click to watch video. Credit: NASA

“It jumped right out at me, it was so bright,” said Ron Suggs, an analyst at the Marshall Space Flight Center. He was the first to notice the explosion in recordings made with a 14-inch telescope maintained by NASA’s lunar impact observation program. Observers there have been video monitoring the moon for the past 8 years looking for signs of explosions caused by meteoroids hitting the surface. Since 2005 the team has detected more than 300 strikes, but the St. Pat’s Day impact was the biggest and brightest to date.

Based on the flash brightness and duration, the space boulder measured between a 1 foot long and a foot and a half long (0.3-0.4 m) and hit the moon traveling at 56,000 mph with a force of 5 tons of TNT.

Artist view of the meteoroid impact last March as seen from the surface. Despite the blog’s title, no actual explosion would be heard because the moon has no atmosphere, however an astronaut would feel the impact through their feet if close enough. Credit: NASA

Remember, the moon has no atmosphere, so there’s nothing to slow down or break apart an incoming meteoroid as happens on Earth so even a small stone can dig a significant hole; its energy of motion transforms it into a powerful little bomb. NASA estimates the crater could be as wide as 65 feet (20 m) across. By the way, the flash of light comes from molten rock and white-hot dust vapor created at the moment of the strike.

NASA’s lunar monitoring program has detected hundreds of meteoroid impacts, nearly all of them on the dark, earthlit areas of the moon where they stand out against the darkened moonscape. You’ll also notice how few have been spotted in the white lunar highland regions. This is a selection effect: flashes stand out much better against black than white. Credit: NASA

That good news because the Lunar Reconnaissance Orbiter should have no trouble spotting the crater once it targets the impact region. Comparing the size of the crater to the brightness of the flash would give researchers a valuable “ground truth” measurement to validate lunar impact models.

A small, relatively fresh lunar impact crater 295 x 230 feet (90×70 m) in diameter photographed by NASA’s Lunar Reconnaissance Orbiter. Melted rock, now solidified, has pooled at the crater’s center. Click for large version. Credit: NASA

In an interesting twist, the very night the moon got smacked, all-sky cameras operated by NASA’s and the University of Western Ontario recorded several bright fireballs streaking through Earth’s skies from the same direction in space as the lunar meteoroid.

“My working hypothesis is that the two events are related, and that this constitutes a short duration cluster of material encountered by the Earth-Moon system,” says Cooke. Who knows. Maybe we’ll see a similar show next March.

 

Earth’s ghostly light touches the crescent moon tonight

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The 2-day-old crescent moon shines over a bog north of Duluth, Minn. last night. Light reflected from the Earth faintly illuminates the moon’s full outline. Details: 200mm f/2.8, ISO 800, 1/2″ exposure. Photo: Bob King

Wow, the moon sure looked lovely last night. At dusk it was a sharp crescent against the blue sky, but later the entire disk was visible thanks to the the Full Earth. Full Earth? Had you been able to stand on the moon and look back in this direction, you would have seen our planet hanging like a big, blue ornament in the velvety black lunar sky. When the moon’s a sickle, light reflected from Earth – called earthshine – lights up the part of our satellite still in shadow.

Earth and moon phases complement one another. The top strip shows the moon phases and the bottom the corresponding Earth phases seen by an astronaut standing on the moon’s surface looking back at Earth. One difference: Earth appears almost 4 times bigger than the moon. Illustration: Bob King

Moon and Earth phases are complementary. A thin crescent in our sky means a person standing on the moon sees a nearly full Earth. A half moon here means a half-Earth there, and around the time of full moon, our lunar astronaut sees a crescent Earth.

A ramble across the earthlit portion of the moon in binoculars will reveal large dark areas (lunar seas) and several bright blotches – the craters Tycho, Copernicus and Aristarchus. Photo: Bob King

Sunlight reflected from our blue, cloud-streaked globe gently illuminates the full outline of the moon. Since the light is reflected rather than direct sunlight, earthlight is faint and rather mysterious-looking. From the surface of the moon, it resembles twilight here on Earth. The crescent itself is lit directly by the sun and appears brilliant in comparison.

Earthshine is twice-reflected sunlight – one bounce off the Earth to the moon and then a bounce back from the moon to Earth. Both moon and Earth absorb much of the sun’s light, which is why earthshine appears faint compared to the sunlit crescent. Illustration: Bob King

A full Earth reflects a lot of sunlight back at the moon, so earthshine is brightest when the crescent is thinnest. As the moon’s phase waxes to half and beyond, the Earth’s phase wanes, going from full to half to crescent. With less Earth to reflect sunlight, earthshine gets fainter and fainter. It also doesn’t help that the area for the Earth to illuminate shrinks as the sunlit portion of the moon grows ever larger night after night.

Jupiter (top left) and Venus (lower right) joined the crescent during twilight last night. Tonight the moon will be to the left of Jupiter. Photo: Bob King

Tonight’s crescent moon will be higher up in a darker sky, so the smoky earthlight should be even easier to see. When you step out for a look, you’ll also see a brilliant “star” a fist to the moon’s right. That’s Jupiter. If you have binoculars, take a minute to study the earthlit portion – you’ll see a surprising number of features there including several large dark areas (the lunar seas) and even a few craters, which look like bright spots.

See today’s ring-of-fire eclipse on the Web

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During an annular eclipse like the one that happen later today, a ring of fire encircles the moon (seen in silhouette). Credit: Wikipedia

The New Moon will pass squarely in front of the sun later today treating anyone living along its shadow path to an annular eclipse. That path cuts across Australia, eastern Papua New Guinea, the Solomon Islands, and the Gilbert Islands. Sky watchers across a much broader region of the Pacific including Australia and Indonesia will witness a partial solar eclipse. The rest of us can happily watch it on the Web.

Diagram showing how the sun, moon and Earth are aligned during a total solar eclipse.The moon’s shadow, called the umbra, traces out a narrow path across the Earth’s surface as the moon covers up the sun. An annular eclipse is similar except the umbral shadow doesn’t quite reach Earth, leaving a ring of sunlight exposed.

An annular eclipse happens when the moon is at apogee, its most distant point from Earth in its monthly orbit. Being farther away, it’s too small to completely cover the sun during totality, leaving a narrow ring or annulus of sunlight hanging in the sky like a fiery wedding band.

Earth globe showing the path of today’s annual eclipse (in red). The blue lines show where a partial solar eclipse will be seen. Click image for more details. Credit: Fred Espenak

Unlike a total solar eclipse, where the moon completely blocks the sun and makes its safe to look at, solar filters are required during all phases of an annular eclipse.

That’ll all be taken care of when you head to the Web later today to see the wonder for yourself. The eclipse starts around 5:30 p.m. Central time over Australia. Here are a couple places to check out:

* SLOOH Space Camera. Webcast begins at 4:30 p.m. Central Daylight Time (2:30 p.m Pacific)

* Coca-Cola Space Center. Webcast starts at 4 p.m. Central (2 p.m. Pacific)

* Solar Eclipse Australia.  Start checking around 4:30 p.m. Central time

Click to watch video to help you visualize how the eclipse will play out.

Fingernail moon, aurora watch and Comet PANSTARRS made easy

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The lunar crescent ascends the western sky over the next few nights dropping by two star clusters and one bright planet. The map shows the sky about an hour after sunset. Maps created with Stellarium

The moon has returned to sweeten the evening. Watch for a thin crescent low in the western sky tonight below the Seven Sisters star cluster. Tomorrow it moves upward, thickens a bit and shines near the V-shaped Hyades star cluster. Topping off the weekend, the crescent will stand just 2 degrees left of the planet Jupiter Sunday. If there ever was a gift that keeps on giving, it’s the moon.

To find PANSTARRS at dusk, use binoculars or a telescope and face northwest about 90 minutes after sunset. Look for the bright zigzag of Cassiopeia, point your instrument at the brightest star nearest the comet and “sta hop” in its direction. This map shows the sky 1 1/2 hours after sunset.

Time to catch Comet PANSTARRS … again. While it’s faded to near the naked eye limit, it’s still plainly visible in binoculars, particularly 7×50 or 10×50 models or larger. The comet is probably easier to find than ever because it’s passing through the bright W-shaped constellation Cassiopeia during the next two weeks. Look for it about 90 minutes after sunset in the northwestern sky. PANSTARRS has a brighter head topped by a faint, fan-shaped tail.

Face northeast about 90 minutes before sunrise and find the W of Cassiopeia. Use it to guide you to the comet.

While observers in the northern U.S., Canada and Europe will get equally good views at both dusk and dawn, sky watchers in the southern U.S. will have better luck at dawn when Cassiopeia is higher in the sky. The view through a telescope is still the best with the comet showing  a bright head and nucleus and a classic, gently-curving tail to the north.

Comet PANSTARRS with its amazing tail photographed on April 10 in Austria. Credit: Michael Jaeger

More good news. A strong solar flare erupted in sunspot group 1719 early Thursday morning April 11 sending sprays of solar protons and electrons in Earth’s direction. You know what that means.

The solar flare in sunspot group 1719 photographed in ultraviolet light by NASA’s Solar Dynamics Observatory around 3:30 a.m. CDT April 11. Credit: NASA

Major storm levels and auroras are possible overnight tonight through Sunday the 14th. With little interference from the moon, this could be a good show. I’ll be keeping an eye on the space weather and send out an alert this evening if auroras sprout.

 

Two new man-made craters grace the moon

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The lunar craters Archimedes (top) and Eratosthenes and the Apennine Mountains. All these features will be visible in the northern half of the moon tonight March 20.

I’m a happy cheerleader for the moon. I think it’s because I’ve stared at countless faint galaxies and spent hours eking out planetary details through choppy air. So last night, when I turned the telescope at the first quarter moon, it felt as though I’d arrived in the garden of plenty.

Craters everywhere, rugged mountains poking from the beige cream of the lunar seas and beautiful shadows stretching like figures in a Dali painting across a landscape at once familiar and yet totally alien.

There’s so much to enjoy even in small scopes at low power. A magnification of 50-75x is sufficient to see most of the features in the photo at right.

This Lunar Reconnaissance Orbiter image shows the impact site of GRAIL A (Ebb spacecraft) before and after the spacecraft’s descent to the lunar surface. The crater is about 13 to 20 feet across. Credit: NASA/GSFC/ASU

I’d love to feast my eyes on the two freshly-minted, man-made craters punched into a mountainside near the moon’s north pole. On Dec. 17, 2012, the twin GRAIL probes, nicknamed Flow and Ebb, were intentionally crashed there after wrapping up a successful mission mapping the moon’s gravity field and interior.


Animation showing the final flight path for NASA’s twin Gravity Recovery and Interior Laboratory (GRAIL) mission spacecraft as they headed for crash landings

Why smack the moon? It was NASA’s plan to squeeze one last bit of science out of the mission. The Lunar Reconnaissance Orbiter (LRO), which orbits the moon and takes closeup photos of it surface, was placed into position to study the last whiffs of the dust plumes kicked up by the two washing-machine-sized probes. Each weighed 440 lbs. (200 kg) and were traveling at 3,800 mph (6,100 km/h) when they struck the mountain.

The twin GRAIL space probes orbited in tandem about the moon. Subtle changes in the gravity exerted on each during orbit caused the distance between them to vary. By measuring the distance variations, astronomers mapped the moon’s gravity field. Credit: NASA

Later, the LRO’s camera zoomed in for a look at the two craters resulting from the crashes and pinpointed them both despite their tiny size – only 13-20 feet (4-6 meters) in diameter. Named Ebb and Flow (of course!), they’re surrounded by faint, dark ejecta or rock sprays gouged from the crust during impact.

Rays of brighter dust and rock surroud younger craters on the moon. With time, the dust darkens in sunlight. At bottom are craters Aristarchus (left) and Kepler. Copernicus is at top.

Radiation in sunlight darkens lunar dust. Fresh lunar craters are typically surrounded by bright ejecta rays created since the impact exposes dust and rock beneath the surface that’s been shielded from sunlight. Ebb and Flow are ringed in darker material; scientists suspect spacecraft material has mixed with the ejecta adding yet another “we were here” signpost to the scene.

I’ll return to observing the moon the next clear night. Maybe I’ll get even luckier than I did on Tuesday. Along the edge of its unlit half, a bright star in Gemini hovered briefly before suddenly disappearing behind the moon. These little “coverups” occur regularly as the moon rolls along its orbit, hiding and then “releasing” this star and that. On good nights, lunar observers are like that star, completely absorbed by our nearest cosmic neighbor.

St. Pat’s aurora update plus a pleasing lunar lineup tonight

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Green auroral rays topped with pink from earlier this morning near Cloquet, Minn. photographed by Matthew Moses

The sun’s wind of particles has been pounding Earth’s defensive magnetic shield since early this morning. A magnificent display of auroras erupted in response. While hurricane winds can reach over 200 mph, they’re nothing compared to solar wind speeds. Top speed for this storm happened at 5:07 a.m. CDT this morning  when electrons and protons hit the magnetosphere at 477 miles per second (767 km/s) or 1.7 million mph. Of course we’re talking about a very dilute soup of particles compared to the far denser atmosphere, hence the destructive power of a hurricane.

The colorful donut shows the extent of the auroral over at 6:53 p.m. Central time this evening recorded by the POES satellite. Red is a good indicator of strong auroral activity. Let’s hope it’s still there when the U.S. rotates under it later this evening. Credit: NOAA

The storm has continued throughout the day at high levels. Judging by recent satellite plots of the auroral ovals, those vast caps of northern and southern lights centered on Earth’s magnetic poles, residents of the Scandinavia countries, Iceland and Greenland must be experiencing a great light show at the moment.

Auroras look to continue into the evening hours tonight for southern Canada and the northern U.S. once darkness returns. The latest forecast calls for minor storms, but you never know. If it’s clear, walk your dog and keep your eyes to the sky.

Watch the moon slowly slip between Jupiter and Aldebaran tonight. This map shows the sky facing southwest around 10:30 p.m. Central time. Stellarium

Even if auroras fail to materialize, the moon has something fun in store. Tonight it will march  directly between the planet Jupiter and Aldebaran, the brightest star in Taurus the Bull. The three will be closest to a perfect lineup one atop the other around 10:30 p.m. Central time or 8:30 p.m. Pacific. If you look early and then check back a hour or two later, you’ll easily see how quickly the moon moves through the sky as it orbits the Earth.

Comet PANSTARRS shares stage with crescent moon

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Dave Kodama took this superb picture of Comet PANSTARRS and the lunar crescent last night from southern California. Details: 180mm lens at f/2.8, ISO 1600 and 1/2″ exposure. Click for larger version. Credit: Dave Kodama

What raw beauty! It almost hurts to look at these if clouds have frustrated you these past nights. I’m grateful we can at least see them through the eyes of others. Thanks to the moon’s proximity, some folks finally got their first looks at Comet C/2011 L4 PANSTARRS last night.

Many observers report that the comet is faint with the naked eye, but shows up well in binoculars and through the camera. Have patience. PANSTARRS is moving farther and farther up and away from the sun into a dark sky. Later this week it should become much more obvious even as it slowly fades.

Another view of PANSTARRS and the moon last night photographed by amateur astronomer Mike Holloway who runs the Holloway Comet Observatory in Van Buren, Ark. Details: 6 sec exp – 220mm lens at f/5.6. Click for larger version.

To those who’ve been plagued with clouds, don’t give up hope. Be persistent and watch the western sky a half hour after sunset for approximately a half hour. In that narrow slot of time PANSTARRS will be best. Tonight the moon will oblige a second time. The comet will appear about one fist held at arm’s length to the lower right of the crescent moon.

Comet PANSTARRS by itself from Southern California last night. Credit: Dave Kodama

Dave Kodama, who took the photo at top, offers this: “It is much smaller than I had been visualizing, and very close to the sunset. I could not see it without binoculars.” Good luck in the hunt!