Dark Energy Camera sees universe through a comet’s tail

At the time this image was taken, the comet was passing about 51 million miles from Earth – a short distance for the Dark Energy Camera, which is sensitive to light up to 8 billion light years away. Each of the rectangular shapes above represents one of the 62 individual fields of the camera. Click to explore the original, hi-res image. Credit:

Comet Q2 Lovejoy on December 27, 2014. At the time this image was taken, the comet was passing about 51 million miles from Earth – a short distance for the Dark Energy Camera, which is sensitive to light up to 8 billion light years away. Each of the rectangular shapes above represents one of the 62 individual fields of the camera. Click to explore the original, hi-res image. Credit: Marty Murphy, Nikolay Kuropatkin, Huan Lin and Brian Yanny

Not a bad photo considering no one planned to shoot this picture of Comet Lovejoy with the  world’s most powerful digital camera. That’s right. The comet just happened to “be in the way” during a scan made by the Dark Energy Camera. A member of the observing team said it was a “shock” to see the comet appear on the computer screen.

An assortment of galaxies including this spiral appear through the tail of Comet Q2 Lovejoy on December 27, 2014 during one of the new Dark Energy Camera's scans of the sky. Credit: Fermilab’s Marty Murphy, Nikolay Kuropatkin, Huan Lin and Brian Yanny

An assortment of galaxies including this pretty spiral appear shine through a small section of Lovejoy’s tail on December 27, 2014 during one of the Dark Energy Camera’s scans of the sky. Credit: Fermilab’s Marty Murphy, Nikolay Kuropatkin, Huan Lin and Brian Yanny

While the detail in the comet is spectacular, what’s behind it is equally amazing. The image represents a narrow but deep slice into the body of the cosmos, revealing hundreds of distant galaxies beyond the green veil of Lovejoy’s tail. I’ve sectioned off a few portions, but I encourage you to download and explore the original file and see the rest for yourself. We’ve all read there are billions of galaxies out there, but seeing them twinkling beyond the comet gives us a visceral feel of how deep the universe goes.

The camera, a 570 megapixel beast with lenses up to a yard across, is mounted on the 157-inch (4-meter) Victor M. Blanco telescope at the National Science Foundation’s Cerro Tololo Inter-American Observatory in the Andes Mountains in Chile. With a 2.2° field of view (much larger than most professional telescopes) and the ability to see light from more than 100,000 galaxies up to 8 billion light-years away in each snapshot, it forms the heart of the Dark Energy Survey (DES).

Another serving of galaxy salad. Credit:

Serving up another helping  of galaxy salad. Credit: Marty Murphy, Nikolay Kuropatkin, Huan Lin and Brian Yanny

Dark energy is the name given to whatever is causing the universe to accelerate. No one went looking for it, but studies of the brightnesses of extremely distant supernovae in the 1990s turned up a phenomenal increase in the expansion rate of the universe when viewed across billions of light years. Now we’re stuck trying to figure out what it is. If anything, most astronomers expected cosmic expansion to slow down as predicted by Einsteins’ Theory of Relativity. Nope.

Overall, dark energy is thought to comprise 73% of all the mass and energy in the universe. 23% is unseen dark matter known only through its gravitational prowess, leaving just 4% ordinary matter for hamburgers, stars and cars.

How the universe divvies up its energy/matter. Credit: NASA

How the universe divvies up its energy/matter. Credit: NASA

The DES designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. The survey will probe dark energy on four fronts:

* Counting galaxy clusters: Dark matter and galaxies’ own gravity hold clusters together, but dark energy tries to pull the clusters apart. The camera will photograph 100,000 clusters across billions of light years of space and time. Counting clusters and mapping their distribution will help us understand how dark energy battles gravity for the fate of the universe.

* Measuring supernovae brightnesses and distances to better determine the expansion rate of the universe. 4,000 new supernovae are expected to be found with the camera.

Fermilab astrophysicist Tom Diehl inspects the Dark Energy Camera.

Fermilab astrophysicist Tom Diehl inspects the 570-megapixel Dark Energy Camera. A high-end consumer camera like the Canon D5 has a full-frame 22.3 megapixel “chip”. Credit: Fermilab

* Studying how dark energy interacts with dark matter. The light of distant galaxies is bent and distorted when it passes around dark matter, warping their shapes. The survey will measure those shapes to see what role dark energy plays in the interaction.

* When the universe was less than 400,000 years old, matter and light interacted to set off a series of sound waves which left an imprint on how galaxies are distributed throughout the universe. The survey will measure the positions in space of 300 million galaxies to find this imprint and use it to infer the history of cosmic expansion.

Even if we don’t track down the nature of dark energy in our lifetime, we can sure enjoy the side benefits of pictures like this one.

Can you feel the Love(joy) tonight? Winter comet now at its best

Comet Q2 Lovejoy sports a faint, blue tail about 5 long while near the Pleiades star cluster last night. The head or coma of the comet is easily visible with the naked eye; the tail shows up in binoculars as a thick, smoky streak pointing to the northeast. The glowing patches in the cluster are caused by cosmic dust reflecting starlight. Details: 200mm telephoto at f/2.8, ISO 800. Credit: Bob King

Darkness came in heaps and lingered for hours last night. Although Comet Q2 Lovejoy competes well with the glare of the city and isn’t hard to see from my driveway, I craved something closer to a classic 18th century, electricity-free sky. That meant putting another 25 miles between me and Duluth.

This photo map will help you find the comet in the next few nights as it passes the Pleiades star cluster. Dates are shown at right from Jan. 11-19. Look high in the southeast at nightfall to spy the dipper-shaped cluster then look about one fist to its right. The comet looks like a dim, slightly fuzzy star of 4th magnitude. Credit: Bob King

From the countryside it was easy to just find the Pleiades or Seven Sisters star cluster and jump from there to the comet. As you can see from the photo map, Lovejoy will be near the cluster the next few nights. There’s still no moon in the sky, so I encourage to go out now for a look if you haven’t already. Even if you’ve seen it once or two, the comet bears watching every clear night. Fluctuations in the solar wind continuously change the shape, length and appearance of the ion or gas tail that’s so outrageously beautiful right now.

Comet Lovejoy time exposure made through an 8-inch (20-cm) telescope on January 14th. Beautiful! Click to immerse yourself. Credit: Gerald Rhemann

To my eyes, Lovejoy looked a little brighter (magnitude +3.8) last night than a week ago when it was closest to Earth. Even in 50mm binoculars you can see the pale blue color of the head or coma. The spectacular tail rays depicted in deep photos are much harder to make out. I could just detect a couple of them faintly in a 15-inch telescope when I moved the bright coma out of the field of view and allowed my eyes to fully dark-adapt. Tapping the telescope to bounce the comet around helped to make them stand out better.

Insane high resolution view of Comet Lovejoy’s ion or gas tail on January 11th. Heat from the Sun is responsible for cooking comet ice, which vaporizes and releases gases and dust to form a tail. UV light from the Sun then ionizes or electrified the gases and the solar wind wraps around the comet and drags them into multiple tail rays. Credit: Damian Peach

We’ve got about another week of dark, moonless skies ideal for comet watching. Perihelion or closest approach to the Sun occurs on January 30th, so Lovejoy’s brightness may remain constant during this time even as it moves farther from Earth.

Did you catch the Saturn-moon conjunction this morning? It was cloudy in Duluth, Minn. but around 7:15 a.m. a few brief holes opened up, showing the pair. Credit: Bob King

While you’re at it, point your binoculars at the nearby Pleiades for a face-full of stars. They’re my favorite in binocular cluster because the group comes alive with far more stars than are visible with the naked eye.

I hope you were able to see the conjunction of Saturn and crescent moon earlier today. I wasn’t able to see it at the optimal time in a dark sky at the start of dawn, but we still got a glimpse here.

On Sunday I’ll include a brand new map for tracking Comet Lovejoy over the next two weeks as it continues its northward climb.

Comet Lovejoy’s tail gets pinched / Let there be (refracted) light!

Lovejoy gets kinky. In this photo taken January 8th, the comet’s tail is caught in the act of separated from the head or coma. Magnetic fields embedded in the stream of particles from the Sun occasionally reconnect on the rear side of a comet and pinch off its tail. Credit: Rolando Ligustri

Looks like Comet Lovejoy got its locks trimmed again. A flutter of solar wind swung round the comet and pinched off its tail, an event captured in the dramatic photo above. You can already see a new tail growing in place.

The solar wind, a dilute stream of electrons and protons blown free of the Sun, wafts across the solar system and touches everything from the biggest planet to the smallest comet.

An ion or gas tail like the one in the photo forms when cometary gases, primarily carbon monoxide, are ionized by solar radiation and lose an electron to become positively charged. Once “electrified”, they can be twisted, kinked and even snapped off by magnetic fields embedded in the Sun’s particle wind.

Having passed closest to the Earth on January 7th, Comet Lovejoy is now high in the southeastern sky at nightfall and near its maximum brightness of 4th magnitude. It’s a little dim with the naked eye, but once you know where to look, I think you’ll be surprised how easy it stands out. At least from the less light-polluted outer suburban and rural areas.

If you can find Orion, you can find the comet. Use Betelgeuse and Rigel (above and below the constellation’s 3-star belt) to form a right triangle with Comet Lovejoy. Once you fix the spot with your eyes, you may see the comet directly. If not, just point your binoculars there and sweep around a bit. Source: Stellarium

I’ve been using bright stars in Orion and Taurus to first guide my binoculars – and then my eye – to the comet. It’s easy to use two bright stars, like Aldebaran and Betelgeuse, and extend a line from each to form a triangle with Lovejoy at one of the corners. If you then point binoculars at that spot in the sky, the comet should pop out. You can then lower the binoculars to see if you can spot it with your naked eye.

The map above is drawn just for tonight. Click HERE for a map showing the comet’s changing position through January 23rd.

A halo rings the bright moon and planet Jupiter (upper left of moon) Wednesday night. Ice crystals in high cirrostratus clouds bends or refracts moonlight into a circle of light. Credit: Bob King

Two nights ago, when I last looked at the comet, a bank of icy cirrostratus clouds moved in around moonrise and created a lovely halo around the moon and Jupiter. These familiar high, wispy clouds are composed of myriad six-sided ice crystals resembling the cells in a honeycomb. Light entering one side of the crystal is refracted or bent out another side. Add up billions of these tiny bits of bent light and they to form a circle around the Sun or moon called a 22-degree halo. The number indicates the radius of the halo or distance from the moon to the edge.

The Sun rises over a “steamy” Lake Superior in Duluth this morning as seen through the window of a local hospital. Credit: Bob King

At the moment, a large swath of the U.S. is steeped in bitter cold air. That often means clear skies at night. Allow yourself at least 5-10 minutes to get your eyes used to the darkness and then another 5 hunting for the comet. If you plan it right, you can be in and out in 20 minutes!

Patches of iridescent colors glow near the Sun an hour after sunrise this morning. Light scattered or diffracted by the extremely small ice crystals in the clouds creates a full range of vivid colors. A single sundog glows at left from light refracted by ice crystals in lower clouds or perhaps within a frozen wisp of vapor rising from the lake. Credit: Bob King

In Duluth, Minn. this morning the temperature dipped to around -10F°. Whenever we go below zero, water vapor above warmer Lake Superior condenses in the chill air into curly wisps of fog locally known as “steam fog”. This made for a very pretty sunrise. If that wasn’t enough, high altocumulus clouds passed near the Sun shortly after sunup, creating a palette of delicious greens, reds and purples. We even had a solitary sundog appear for a few minutes in a different set of lower clouds composed of ice crystals.

A closer view of the Sun and the strikingly beautiful iridescence. Click to learn more about diffraction and iridescence. Credit: Bob King

What a treat for the eyes! My wife and I saw all this unfold from the window of one of the local hospitals where we’d gone for a routine procedure. Whenever light puts on a show like it did this morning, I always tell myself I really need to get up earlier to catch more sunrises. And pack something a bit higher-end than a mobile phone!

See Comet Lovejoy with the naked eye this week

Comet Lovejoy on December 29th when it passed near the globular cluster M79 in Lepus the Hare. At around 4th magnitude, the comet will remain well above the naked limit for the next couple weeks. Credit: Joseph Brimacombe

Are you ready to see a comet with nothing more than your eyeballs? Comet Q2 Lovejoy has been growing steadily brighter in the past few weeks. Now at magnitude 4.5 and still rising, it broke the 6th magnitude naked eye limit back about December 22nd.

Most comet aficionados take a break from comet watching during full moon because moonlight washes out all the fun fuzzy stuff. But Lovejoy’s got what it takes. I’ve been watching it from home right through last night’s full moon with nothing more than a pair of 8×40 binoculars.

A sketch of the comet as seen in 8×40 binoculars last night in bright moonlight. Credit: Bob King

Lovejoy now glows at around magnitude 4.5, bright enough to see with the naked eye as a dim smudge from outer suburban areas and a chunkier fuzzball from rural skies. In binoculars the glowing coma, brighter toward the center, is unmistakeable.

Beginning tomorrow night, the moon will rise after the end of evening twilight in a dark sky. As each night passes, that slice of darkness grows at the same time Lovejoy tracks ever higher in the south-southeastern sky. That’s as ideal as it gets.

The week begins with the comet in Eridanus the River some two fists held at arm’s length (20°) to the right of Orion’s Belt. Try to catch a look early in the evening before moonrise for the best view. Orion and Eridanus will be in the southeastern sky around 6:30-7 p.m. at nightfall.

By the weekend it will have climbed into the “backwaters” of the familiar constellation Taurus the Bull, midway between Menkar (Alpha Ceti) and orange-red Aldebaran in the V-shaped Hyades star cluster. Come the following weekend, you’ll find Comet Lovejoy midway between the Pleiades and Aries’ brightest star, Hamal, high in the southern sky at twilight’s end.

Comet Lovejoy position is shown for each night tonight through January 23rd. The comet should remain in the 4-5 magnitude range throughout. Click for a larger map you can print out and use outdoors. Source: Chris Marriott’s SkyMap software

If your sky is heavily light polluted, you probably won’t see it without optical aid, but binoculars should suffice. Observers with darker skies should with the naked eye with only a little effort. Look for a smudge of light like a puff of cloud.

In a telescope, you’ll see a blue-green tint to the bulbous coma and perhaps a trace of Lovejoy’s skinny ion or gas tail. The nights ahead should be exciting ones as the moon departs the sky,letting us see the comet in its full glory.

Comet Lovejoy keeps on giving / Bright comet prospects for 2014

Beautiful Comet Lovejoy still shines brightly in the morning sky. This photo was taken on Dec. 27, 2013. Click to enlarge. Credit: Rolando Ligustri

Things have gotten awfully quiet around here ever since Comet ISON left the stage. The half dozen or so comets sprinkled about morning and evening skies are faint and require detailed charts and good-sized telescopes to see and appreciate. Except for Comet Lovejoy. This gift to beginner and amateur astronomers alike keeps on giving.

Still glowing around magnitude 6 (naked eye limit), the comet remains easy to see in binoculars from fairly dark skies as it tracks from the constellation Hercules into Ophiuchus in the coming weeks. Even in last quarter moonlight observers have reported seeing a short tail. Now that the moon is little more than a thin crescent and far away to the south of Lovejoy, conditions are perfect for another look.

Track of Comet C/2013 R1 Lovejoy in the morning sky marked at 3-day intervals shortly before the start of dawn (6 a.m. local time) tomorrow through Jan. 31. Stars shown for Dec. 29 to magnitude 5.8. Her = Hercules and Oph = Ophiuchus. Click to enlarge. Created with Chris Marriott’s SkyMap software

The best time for viewing is shortly before the start of dawn when Lovejoy sails highest in the eastern sky at an altitude of around 30 degrees or “three fists” up from the horizon. By January’s end, the comet will still be 25 degrees high in a dark sky.

Looking ahead to 2014 there are at present three comets beside Lovejoy that are expected to wax bright enough to see in binoculars and possibly with the naked eye: C/2012 K1 PanSTARRS and C/2013 A1 Siding Spring. The first will be easy to track in a small telescope from mid-spring through early summer for northern hemisphere observers as it makes its way from Bootes across the Big Dipper and down through Leo the Lion.

K1 PANSTARRS then disappears in the solar glow for a while before returning to the morning sky in fall for its best showing. Expect it to crest above the naked limit (mag. 5.5) in mid-October just before it dips too far in the southern sky for easy viewing from mid-northern latitudes.

Mars and Comet C/2013 A1 Siding Spring will overlap as seen from Earth on Oct. 19, 2014 when the comet might pass as close as 25,700 miles (41,300 km) from the planet’s center. View shows the sky at the end of evening twilight facing southwest. Stellarium

C/2013 A1 Siding Spring is expected to reach magnitude 7.5 and become binocular-worthy for southern hemisphere skywatchers in September. Northerners will have to wait until early October for the comet to make an appearance in Scorpius and Sagittarius very low in the southwestern sky at dusk. It will still glow around 8th magnitude through late October.

Would that we could see Siding Spring from Mars this fall. On October 19 the comet will pass so close to the planet that its outer coma or atmosphere may brush against that of Mars, possibly sparking a meteor shower. The sight of a bright planet smack in the middle of a comet’s head should be something quite wonderful to see through a telescope.

Comet Oukaimeden may glow around 8th magnitude in late August 2014 when it rises with the winter stars before dawn. Stellarium.

Finally, there’s comet C/2013 V5 (Oukaimeden), discovered November 15 at Oukaimeden Observatory in Marrekech, Morocco. Preliminary estimates place the comet at around magnitude 5.5 in mid-September. It should reach binocular visibility in late August in Monoceros the Unicorn east of Orion in the pre-dawn sky before disappearing in the twilight glow for mid-northern latitude observers. Southern hemisphere skywatchers will see the comet at its best and brightest before dawn in early September and at dusk later that month.

While the list of predicted comets is skimpy and arguably not bright in the sense of beauties like Hale-Bopp or even L4 PANSTARRS from earlier this year,all may become visible with the naked eye from a dark sky site and should present no problems seeing in binoculars.

Every year new comets are discovered, some of which can swiftly brighten and put on a great show just like Lovejoy did last fall several months after its discovery by Terry Lovejoy on September 7. We’ll just have to wait and see what flies our way.

Lovejoy, a comet with a VERY long tail to tell

Mosaic image of Comet Lovejoy on Dec. 13 with a long tail showing numerous kinks, twists and knots from its interactions with the solar wind. Please click to explore and enjoy a MUCH larger version. Credit: Gerald Rhemann

In case you haven’t seen this photo, all ll I can say is … AMAZING. Austrian astrophotographer Gerald Rhemann photographed Comet Lovejoy on Dec. 13 with a tail at least 20 degrees long. That’s more than 40 full moons side by side! The tiny version of the photo I’ve posted only hints at the incredible structures in the comet’s blue gas tail. Click the image to see the monster version. See what I mean?

The kinks, twists and blobs tell the tale of a tail flayed and hammered by the solar wind. Gases like carbon monoxide released from the comet’s nucleus as it vaporizes in sunlight are ionized (electrified) by the sun’s ultraviolet light and form the blue-tinted ion tail. Changing magnetic fields embedded in the sun’s solar wind stream by and interact with the ionized gases, sculpting bizarre shapes and multiple streamers. Like a wind sock, gas tales belie the wind’s strength, speed and direction.

Austrian astrophotographer Gerald Rhemann with his 12″ f/3.6 telescope used to shoot Comet Lovejoy. Credit: Gerald Rhemann

Toward the top of the photo and roughly parallel to the gas tail look for the smooth, pale yellow dust tail. Dust from the comet, released along with the gas, gets pushed back behind the comet’s head by the pressure of sunlight to form a separate tail defining the comet’s curved orbit.

Since dust is neutral, the solar wind doesn’t mess with it like the ionized (electrified) gases in the ion tail.

Lovejoy’s tail will likely grow even longer as the comet heads toward perihelion (closest approach to the sun) on December 23 and solar heating intensifies.

Unfortunately, the comet has been slowly moving away from Earth and slowly fading since late November.

This map shows the sky facing east-northeast about two hours before sunrise. Comet Lovejoy’s position is shown every 3 days through Dec. 30. Click for large version. Created with Chris Marriott’s SkyMap program

At the moment, Lovejoy’s making its way across the constellation Hercules and best viewed in the morning sky just before the start of dawn when it stands some 30 degrees above the eastern horizon. For observers in mid-northern latitudes, Hercules is also visible very low in the evening sky with the comet just 10 degrees high and dropping lower by the night.

Although compromised by moonlight, it’s still visible in binoculars and small telescopes glowing around magnitude 6. In about a week, the moon will be a crescent and much less of a bother. The tail will be much more obvious at that time.

Comet ISON update Dec. 4 – A Stubborn Fellow

Low-resolution image from one of the cameras on STEREO-A taken on Dec. 1. Called a “beacon image” it’s a frame from a 24-hour daily stream of data from the spacecraft. Credit: NASA

Comet ISON lives! OK, it might be on life support, but the comet written off as dead a week ago still glows in recent photos taken by the STEREO-A cameras. While no one’s seen it from the ground yet, we’re getting close to that opportunity.

One of the latest STEREO-A beacon photos may or may not show the comet. For some reason, the resolution in photos made today is poor, making the comet’s identification dificult. Credit: NASA

This Saturday Dec. 7 the comet will appear very low in the southeastern sky for a brief period just before the start of morning twilight. I doubt anyone will see it with their eyeballs but intrepid astrophotographers are eager to photograph it.

High resolution photo from STEREO-A’s H1 heliospheric imager camera showing Comet ISON on Dec. 1. Although taken at the same time, it appears fainter here. Differences in picture quality and exposure are probably why. Credit: NASA

Latest hi-resolution photo from STEREO-A shows continued fading of Comet ISON. Credit: NASA

Based on these photos, the latest I could find, ISON shines about as brightly as the nebulosity in and around the Pleiades star cluster. Not bright by any stretch, small telescopes will still show the brightest parts of the cluster’s cocoon-like nebula from a dark sky. That’s my educated guess on the comet’s potential visibility. Hopefully we’ll see photos and magnitude estimates from the ground very soon.

Most recent STEREO-A image published Dec. 3 at 4:49 p.m. CST only hints at the comet’s presence. Credit: NASA

UPDATE Dec. 5: Latest hi-res STEREO-A photo shows ISON barely there.

Comet Lovejoy photographed this morning from Italy. Details: Camera piggybacked on a telescope, 430mm lens at f/6.3, 142 second exposure, ISO 800. Credit: Giorgio Rizzarelli

One comet remains bright – Lovejoy. It’s traveling through the constellation Bootes in the wee hours before dawn and can still be viewed in binoculars. Click HERE for a finder map.

Move over ISON, time to share the love with Comet Lovejoy

Comet Lovejoy (C/2013 R1 Lovejoy) at 2:30 a.m. this morning Nov. 29, 2013. The comet was faintly visible with the naked eye and a pretty sight in binoculars. Details: 70-second exposure, ISO 800, 70mm f/2.8 on a tracking mount. Credit: Bob King

In the furor of following Comet ISON, we’ve almost lost track of another fine, fuzzy fellow – Comet Lovejoy. Last we checked in on this comet during the first half of November, it had swelled to almost half a degree in diameter with a 2-degree-long tail. From a dark sky the comet was even bright enough to glimpse with the naked eye in moonlight.

This map shows Comet Lovejoy every three days Nov. 30 to Dec. 30 about 2 hours before sunrise in the eastern sky. Click to enlarge. Created with Chris Marriott’s SkyMap software

I’m here to tell you it’s still all of those things. With the moon out of the sky, I could see Lovejoy without difficulty with the naked eye near the star Gamma in the constellation Bootes below the handle of the Big Dipper early this morning. It looked like a small fuzzy blob of magnitude 4.6.

Comet Lovejoy through a 200mm telephoto lens on a tracking mount this morning. Credit: Bob King

10×50 binoculars really did the comet justice. With them a beautiful, gossamer tail stretched across half the field of view or about 2.5 degrees. One degree is the amount of sky you can cover with your pinkie finger held at arm’s length. The photos closely match my visual impression of the tail through the 10x50s.

Beautiful pairing of Comet Lovejoy and the galaxy M63 on Nov. 25, 2013. Click to enlarge. Credit: Damian Peach

Through a 15-inch telescope at low magnification, Lovejoy’s monster-sized head (just under half a degree, the diameter of a full moon) glowed pale blue-green highlighted by a bright, fuzzy dot at its center – the false nucleus. The real comet nucleus always remains hidden in its wraps of dust and gas.

Closeup of Comet Lovejoy’s false nucleus (dot) with a plume of dust sticking out to the left on Nov. 12, 2013. Credit: Luc Arnold

Upping the magnification to 287x, a striking, funnel-shaped fan of dust issued from the false nucleus to the south-southeast. This feature has been a regular part of Lovejoy’s anatomy for at least the past few weeks. I urge observers with 6-inch and larger telescopes to take a look. This amazing jet of dusty material boiling off the comet’s nucleus won’t be visible forever. Use high power and bore right into the coma’s center.

Comet Lovejoy clears the horizon around 1 a.m. (I know -ouch!) but you’ll see it best between 2:30 and the start of dawn when it’s better placed. The comet passed closest to Earth on Nov. 20 – that’s why it’s still bright. As it moves away from Earth it will gradually get dimmer, which makes the coming two moonless weeks the best time to seize the opportunity.

Comet Lovejoy buzzes the Beehive Cluster / Moon, Venus “Christmas” conjunction

Comet Lovejoy, glowing green from fluorescing gases, passes below the Beehive star cluster early this morning. Notice the comet’s short tail pointing up to the west. Details: 200mm telephoto at f/2.8, ISO 800, 70-second exposure. Credit: Bob King

Clouds ruled most of last night but not at 1 a.m. this morning when Comet Lovejoy came up over the trees next to the Beehive Cluster in the constellation Cancer. The comet was very easy to see in 10×50 binoculars as a small, glowing patch alongside the larger spray of stars that make up the cluster.

The moon and Venus in a “triple conjunction” with the big ball on the Christmas tree at Bentleyville Christmas display in downtown Duluth last night. Credit: Bob King

Presently at magnitude 6-6.5, Lovejoy will soon become a naked eye comet for observers with dark skies as it sails northward toward the Big Dipper. I can’t wait. It’s been many months since we’ve had a comet that didn’t require a set of glass eyes to see.

The crescent moon hovers of the LED ball atop the Christmas tree. Credit: Bob King

Do you remember the last bright comet? That would have been L4 PANSTARRS last spring. Many struggled to find it because it was only visible for a short time in bright twilight before setting. Though Lovejoy won’t get nearly as bright, skywatchers can follow it into winter with binoculars and small telescopes.

Did you happen to see Venus and moon at dusk yesterday evening? I caught them shining together over our city’s big Christmas lighting display and couldn’t resist a few photos of this rare “triple conjunction”.

If you’re interested in photographing the moon in twilight, you can do it so long as you can hand-hold your camera at 1/30 – not too tough a task. Compose a scene that includes the moon and start shooting about 30 minutes after sunset, when the twilight glow and moonlight are in balance. Let the camera figure the exposure and check the back replay to see if you’re on the money.

Boo! Ghostly auroras possible on Halloween

A farewell X2-class flare from big sunspot region 1875 as it departed the sun’s face late Tuesday afternoon Oct. 29. Although it blasted out a massive cloud of electrons and protons (see below), the material doesn’t appear to be directed toward Earth. Credit: NASA

Auroras on Halloween? I can’t think of a better fit than the spooky quavering of northern lights. I’m happy to report there’s a real possibility that skywatchers in the northern U.S. and southern Canada might share their treat or treating with an ominous green arc hanging over the northern horizon.

Aftermath of the X2 flare from sunspot region 1875 – a massive burst of particles lifts off the sun to the right. Photo made with a coronagraph, which blocks the sun so astronomers can study the sun’s corona or atmosphere. Credit: NASA / SOHO

Space weather experts are forecasting a 20 percent chance of minor geomagnetic storms and accompanying auroras for mid-latitudes through tomorrow night. Northern lights were expected this past weekend from the combined effects of several flares. The continuing parade of large sunspot groups and their associated solar flares have sent several particle blasts in our direction. None ever found a way past Earth’s magnetic defenses to spark a display of northern lights.

Let’s hope that changes on Halloween. That’s when the effects of a M4-class (medium-sized) flare from sunspot region 1882 will arrive. Clouds of high-speed subatomic particles and tangled magnetic fields lofted into space from the explosion are on the way; be on the lookout tonight and tomorrow night. All the aurora indicators have been very low the past week, but I noticed today that the Kp index has been ticking up, a good sign.

Waves of CME (coronal mass ejection) material sweep past Comet Lovejoy earlier this week in an animation of STEREO space probe images compiled by Alan Watson.

Comet Lovejoy, now visible in binoculars in the morning sky, has recently grown a narrow tail of fluorescing gas called an ion tail. Like a windsock, an ion tails wiggles and warps according to changes in speed and intensity in the wind of particles released by the sun.

Kinking and bending in the ion tail of Comet Lovejoy seen here on Oct. 29 may be result of the passage of waves of solar particles entwined with magnetic fields. Credit: Gerald Rhemann

All those recent coronal mass ejections sent waves of particles across the solar system, some of which flowed right across the comet and may have caused a twist in its tail recorded by amateur astronomers earlier this week. The animation, compiled by Alan Watson from images taken by NASA’s STEREO sun-watching spacecraft, show the waves very clearly.

For more on finding Comet Lovejoy and the three other bright-ish comets in the morning sky, please see my article Four Comets Haunt the Halloween Dawn on Universe Today. Detailed maps are included.