Where to Look for Comet Lovejoy Until it Fades from Sight

I hate to admit it, but our dear comet is fading. Only a little though. As Comet Q2 Lovejoy wends its way from Earth toward perihelion and beyond, it will slowly dim and diminish. With an orbital period of approximately 8,000 years it has a long journey ahead. Down here on Earth, we continue to look up every clear night hoping for yet another look at what’s been a wonderful comet. 

Comet Lovejoy and the Pleiades on January 19, 2015. Credit: Joseph Brimacombe
Comet Lovejoy and the Pleiades on January 19, 2015. Credit: Joseph Brimacombe

Despite its inevitable departure I encourage you to continue following Comet Lovejoy. It’s not often a comet vaults to naked eye brightness, and this one should remain visible without optical aid through mid-February.

Like a human celebrity, Lovejoy’s been the focus of attention from beginners and professionals alike using everything from cheap cellphone cameras to high-end telescopes to capture its magic. Who can get enough of that wildly fluctuating ion tail and greeny-blue coma?

Comet Q2 Lovejoy continues tracking north-northwest now through March. This chart shows the comet's position at 7 p.m. (CST) every 5 nights through March 5. Stars shown to magnitude +6. Created with Chris Marriott's SkyMap software
Comet Q2 Lovejoy continues tracking north-northwest now through March. This chart shows the comet’s position at 7 p.m. (CST) every 5 nights through March 5. Stars shown to magnitude +6. Click to enlarge. Created with Chris Marriott’s SkyMap software

The comet continues moving northward all winter long, sliding through  the diminutive constellations Aries and Triangulum, across Andromeda and into Cassiopeia, fading as she goes. You can use the map above and binoculars to help you follow it. I like to create lines and triangles using bright stars and deep sky objects to direct me to the comet.

Deep image of Comet Lovejoy taken with a Canon 6D with 50mm f/1.4 lens at f/2. 10  exposure of 30 secs at ISO3200 stacked. The tail, though faint, extends for possibly 18 degrees in this amazing image. Credit: Ian Sharp
Deep image of Comet Lovejoy taken with a Canon 6D with 50mm f/1.4 lens at f/2. Ten exposures of 30 secs at ISO3200 were stacked to create the final photo. The tail extends for possibly 18 degrees in this amazing image. The Pleiades are at top right; Hyades at bottom center. Credit: Ian Sharp

Tonight for instance, Lovejoy one fist held at arm’s length due west of the Pleiades. On the 29th, it’s on a line from Beta Persei (Algol) to Beta Trianguli. On February 3rd, it pulls right up alongside the colorful double star Gamma Andromedae, also called Almach, and on the 8th forms one of the apexes of an equilateral triangle with the two Betas. You get the idea.

The tail rays that show so clearly in photographs as in this image made on January 16th require dark skies and 8-inch or larger telescope to see visually. They're very low contrast. Credit: Greg Redfern
The tail rays that show so clearly in photographs as in this image made on January 16th require dark skies and an 8-inch or larger telescope to see visually. They’re very low contrast. Credit: Greg Redfern

The waxing moon will interfere with viewing beginning next weekend and render the comet nil with the naked eye, you’ll still be able to track it in binoculars during that time. Dark skies return around Feb. 7.

Comet Lovejoy captured from the Dark Sky Alqueva Reserve, Portugal on Jan. 11th by Miguel Claro

Delicate streamers show in Comet Lovejoy's ion tail in this photo from January 13th. Credit: Bernhard Hubl
Delicate streamers show in Comet Lovejoy’s ion tail in this photo from January 13th. Credit: Bernhard Hubl

How to Find and Make the Most of Comet Lovejoy

Comet Q2 Lovejoy passed closest to Earth on January 7th and has been putting on a great show this past week. Glowing at magnitude +4 with a bluish coma nearly as big as the Full Moon, the comet’s easy to see with the naked eye from the right location if you know exactly where to look. I wish I could say just tilt your head back and look up and bam! there it would be, but it’ll take a little more effort than that. But just a little, I promise. 

Comet Lovejoy and its spectacular "lively" ion tail photographed on January 8th by Nick Howes at Tzec Muan Network at Siding Spring Australia
Comet Lovejoy and its spectacular “lively” ion tail photographed on January 8th by Nick Howes at Tzec Muan Network at Siding Spring Australia

Last night, under a dark rural sky, once I spotted the comet and noticed its position in relation to nearby bright stars, I could look up and see it anytime. Finding anything other than the Moon or a bright planet in the night sky often requires a good map. I normally create a star-chart style map but thought, why not make a photographic version? So last night I snapped a few guided images of Lovejoy as it glimmered in the wilds of southern Taurus and then cloned the comet’s nightly position through onto the image. Maybe you’ll find this useful, maybe not. If not, the regular map is also included.

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. Click to enlarge and print for use outdoors. Source: Chris Marriott’s SkyMap software
Comet Lovejoy’s position is shown for each night tonight through January 23rd. The comet should remain in the 4-5 magnitude range throughout. Lovejoy is currently high in the southeastern sky at nightfall and crosses the meridian due south around 9 o’clock local time. Click for a larger map you can print out and use outdoors. Source: Chris Marriott’s SkyMap software

To see Comet Lovejoy with the naked eye you’ll need reasonably dark skies. It should be faintly visible from outer ring suburbs, but country skies will guarantee a sighting. I’ve been using bright stars in Orion and Taurus to guide binoculars – and then my eye – to the comet. Pick a couple 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. If you don’t find it immediately, sweep around the position a bit.  After you find it, lower the binoculars and try to spot it with the naked eye.

Comet Lovejoy last night January 9th around 8 p.m. (CST) shows a bright coma and faint ~1.5-degree-long
Comet Lovejoy last night January 9th around 8 p.m. (CST) shows a bright coma and faint ~1.5-degree-long tail. This photo, made with a 200mm lens, gives a good idea of what the comet looks like in 50mm binoculars. Details: f/2.8, ISO 800, 2-minute exposure. Credit: Bob King

This week, as Lovejoy continues trekking north, you can use bright orangey Aldebaran in Taurus and the Pleiades, also called the Seven Sisters star cluster, to “triangulate” your way to the comet. Look for a glowing fuzzball. In 10×50 and 8×40 binoculars, it’s obviously different from a star — all puffed up with a brighter center. The 50mm glass even shows a hint of the coma’s blue color caused by carbon molecules fluorescing in ultraviolet sunlight and a faint, streak-like tail extending to the northeast. With the naked eye, at first you might think it’s just a dim star; closer scrutiny reveals the star has a hazy appearance, pegging it as a comet.

Comet Lovejoy sketches from last night made using a 15-inch telescope. The coma is big - almost a half-degree across. The drawing shows the bright nuclear region and tiny "false nucleus". At right, a suspected plume extends to the southwest of the false nucleus. Color is how the comet really looks in the telescope. Credit: Bob King
Comet Lovejoy sketches from last night made using a 15-inch telescope. The coma is big – almost a half-degree across. The drawing shows the bright nuclear region and tiny “false nucleus”. At right, a suspected plume extends to the southwest of the false nucleus. Color is how the comet really looks in the telescope. South is up. Credit: Bob King

Through a telescope the coma is a HUGE pale blue tiki lamp of a thing with a small, much brighter nuclear region. The rays of the ion tail, so beautifully shown in photographs, are indistinct but visible with patience and a moderate-sized telescope under dark skies. At low magnification, the nucleus – the false nucleus actually, since the real comet nucleus is hidden by a shroud of dust and gas – looks like a misty star of about magnitude +9. On close inspection at high magnification (250x and up), you penetrate more deeply into the nuclear zone and the star-like center shrinks and dims to around magnitude +13.

Fascinating plumes of dust recorded by Gianluca Masi on January 6th. South is up, west to the left. Credit: Gianluca Masi
Fascinating plumes of dust recorded by Gianluca Masi on January 6th. South is up, west to the left. Credit: Gianluca Masi

If the seeing is good and comet active, high magnification will often reveal jets or fans of dust in the sunward direction, in this case west of nucleus. I’ve been studying the comet the past couple nights and am almost convinced I can see a short, very low contrast plume poking to the south of center. Generally, plumes and jets are subtle, low-contrast features. Challenging? Yes, but with Lovejoy as close as it’s going to get, now’s the time to seek them.

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
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. A new one quickly grows to replace the old. Credit: Rolando Ligustri

Just before Christmas, fluctuations in the solar wind snapped off Comet Lovejoy’s tail. Guess what? It happened again on January 8th as recorded in dramatic fashion by astrophotographer Rolando Ligustri. 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.

Of course, the comet didn’t miss a breath but grew another tail immediately. Look closely at the photo and you see another faint streak of light pointing beyond the coma below and left of the bright nuclear region. This may be Lovejoy’s dust tail. Most comets sport both types of tails – gas and dust – since they release both materials as the Sun heats and vaporizes their ices.

Lovejoy’s been a thrill to watch because it’s doing all the cool stuff that makes them so fun to follow. Gianluca Masi, an Italian astrophysicist and lover of all things cometary, will offer a live feed of the comet on Monday January 12th starting at 1 p.m. CST (7 p.m. UT). May your skies be clear tonight!

Comet Q2 Lovejoy Loses Tail, Grows Another, Loses That One Too!

Maybe you’ve seen Comet Q2 Lovejoy. It’s a big fuzzy ball in binoculars low in the southern sky in the little constellation Lepus the Hare. That’s the comet’s coma or temporary atmosphere of dust and gas that forms when ice vaporizes in sunlight from the nucleus. Until recently a faint 3° ion or gas tail trailed in the coma’s wake, but on and around December 23rd it snapped off and was ferried away by the solar wind. Just as quickly, Lovejoy re-grew a new ion tail but can’t seem to hold onto that one either. Like a feather in the wind, it’s in the process of being whisked away today.

Magnetic field lines bound up in the sun’s wind pile up and drape around a comet’s nucleus to shape the blue ion tail. Notice the oppositely-directed fields on the comet’s backside. The top set points away from the comet; the bottom set toward. In strong wind gusts, the two can be squeezed together and reconnect, releasing energy that snaps off a comet’s tail. Credit: Tufts University.
Magnetic field lines bound up in the sun’s wind pile up and drape around a comet’s nucleus to shape the blue ion tail. Notice the oppositely-directed fields on the comet’s backside. The top set points away from the comet; the bottom set toward. In strong wind gusts, the two can be squeezed together and reconnect, releasing energy that snaps off a comet’s tail. Credit: Tufts University.

Easy come, easy go. Comets usually have two tails, one of dust particles that reflect sunlight and another of ionized gases that fluoresce in Sun’s ultraviolet radiation. Ion tails form when cometary gases, primarily carbon monoxide, are ionized by solar radiation and lose an electron to become positively charged. Once “electrified”, they’re susceptible to magnetic fields embedded in the high-speed stream of charged particles flowing from the Sun called the solar wind. Magnetic field lines embedded in the wind drape around the comet and draw the ions into a long, skinny tail directly opposite the Sun.

Part of Comet Lovejoy Q2's ion tail (left) cuts the cord and floats away from the comet as photographed on December 23, 2014. Credit: Chris Schur
Part of Comet Lovejoy Q2’s ion tail (left) cuts the cord and floats away from the comet as photographed on December 23, 2014. Carbon monoxide in the tail fluoresces blue in ultraviolet sunlight. Credit: Chris Schur

Disconnection events happen when fluctuations in the solar wind cause oppositely directed magnetic fields to reconnect in explosive fashion and release energy that severs the tail. Set free, it drifts away from the comet and dissipates. In active comets, the nucleus continues to produce gases, which in turn are ionized by the Sun and drawn out into a replacement appendage. In one of those delightful coincidences, comets and geckos both share the ability to re-grow a lost tail.


Comet Encke tail disconnection April 20, 2007 as seen by STEREO

Comet Halley experienced two ion tail disconnection events in 1986, but one of the most dramatic was recorded by NASA’s STEREO spacecraft on April 20, 2007. A powerful coronal mass ejection (CME) blew by comet 2P/Encke that spring day wreaking havoc with its tail. Magnetic field lines from the plasma blast reconnected with opposite polarity magnetic fields draped around the comet much like when the north and south poles of two magnets snap together. The result? A burst of energy that sent the tail flying.

Diagram showing how a CME slams into a comet (B) to create a tail disconnection event, known in the biz as a DE. Soon enough the comet grows a new one (D). Credit: NASA
Diagram showing how a CME slammed into Comet Encke (B) and snapped off its tail.  Soon enough, the comet grew a new one (D). Credit: NASA

Comet Lovejoy may have also crossed a sector boundary where the magnetic field carried across the Solar System by Sun’s constant breeze changed direction from south to north or north to south, opposite the magnetic domain the comet was immersed in before the crossing. Whether solar wind flutters, coronal mass ejections or sector boundary crossings,  more tail budding likely lies in Lovejoy’s future. Like the chard in your garden that continues to sprout after repeated snipping, the comet seems poised to spring new tails on demand.

Because Comet Lovejoy rapidly moves into the evening sky by mid-late December, its position on this detailed map is shown at 10 p.m. (CST) nightly. Credit:
Comet Lovejoy picks up speed in late December as it travels from southern Lepus into Eridanus. Its position shown nightly at 10 p.m. (CST). On Sunday night December 28th it passes very close to the bright globular cluster M79. Stars shown to magnitude +8.0. Source: Chris Marriott’s SkyMap software

If you haven’t seen the comet, it’s now glowing at magnitude +5.5 and faintly visible to the naked eye from a dark sky site. Without an obvious dust tail and sporting a faint ion tail(s), the comet’s basically a giant coma, a fuzzy glowing ball easily visible in a pair of binoculars or small telescope.

A second tail disconnection event recorded on December 26, 2014 by John Nassr from his observatory in Baguio, Philippines. The fram is 3 wide. Credit: John Nassr
A second tail disconnection event recorded on December 26, 2014 by John Nassr from his observatory in Baguio, Philippines. The frame is 3° wide. Credit: John Nassr

In a very real sense, Comet Lovejoy experienced a space weather event much like what happens when a CME compresses Earth’s magnetic field causing field lines of opposite polarity to reconnect on the back or nightside of the planet. The energy released sends millions of electrons and protons cascading down into our upper atmosphere where they stimulate molecules of oxygen and nitrogen to glow and produce the aurora. One wonders whether comets might even experience their own brief auroral displays.


Excellent visualization showing how magnetic fields line on Earth’s nightside reconnect to create the rain of electrons that cause the aurora borealis. Notice the similarity to comet tail loss.

Comet Jacques Makes a ‘Questionable’ Appearance

What an awesome photo! Italian amateur astronomer Rolando Ligustri nailed it earlier today using a remote telescope in New Mexico and wide-field 4-inch (106 mm) refractor. Currently the brightest comet in the sky at magnitude 6.5, C/2014 E2 Jacques has been slowly climbing out of morning twilight into a darker sky over the last two weeks. This morning it passed the Flaming Star Nebula in the constellation Auriga. Together, nebula and pigtailed visitor conspired to ask a question of the sky in a rare display of celestial punctuation.  IC 405 is a combination emission-reflection nebula. Some of its light stems from starlight reflecting off grains of cosmic dust, but the deep red results from hydrogen excited to fluorescence by powerful ultraviolet light from those same stars. The depth of field hidden within the image is enormous: the nebula lies 1,500 light years away, the comet a mere 112 million miles or 75 million times closer. Coincidentally, the comet also glows in similar fashion. The short dust tail to the left of the coma is sunlight reflecting off minute grains of dust boiled from the nucleus. The long, straight tail is primarily composed of carbon monoxide gas fluorescing in ultraviolet light from the sun.

Follow Jacques in a small telescope or binoculars in its travels across Auriga into Perseus in the next two weeks before the moon interferes again. Comet positions are shown for 4 a.m. CDT every 5 days. Stars to magnitude +8.0. Click to enlarge. Source: Chris Marriott's SkyMap
Follow Jacques in a small telescope or binoculars in its travels across Auriga into Perseus during the next two weeks before the moonlight interferes. Comet positions are shown for 4 a.m. CDT every 5 days. Stars to magnitude +8.0. Click to enlarge. Source: Chris Marriott’s SkyMap

As Jacques swings toward its closest approach to Earth in late August, it’s gradually picking up speed from our perspective and pushing higher into the morning sky. A week ago, twilight had the upper hand. Now the comet’s some 20º high (two ‘fists’) above the northeastern horizon around 4 a.m. This morning I had no difficulty seeing it as a small, ‘fuzzy star’ in 10×50 binoculars. In my dusty but trusty 10-inch (25 cm) telescope at 76x, Comet Jacques was a dead ringer for one of those fuzzy dingle-balls hanging from a sombrero. I caught a hint of the very short dust tail but couldn’t make out the gas tail that shows so clearly in the photo. That will have to await darker skies.

A different perspective on Comet Jacques. This negative image, which accentuates detail in the comet's tails, was shot July 26, 2014 with an 8-inch (20 cm) telescope. Credit: Michael Jaeger
A different perspective on Comet Jacques. This negative image, which emphasizes details in the comet’s tails, was shot July 26, 2014 with an 8-inch (20 cm) telescope. Credit: Michael Jaeger

Maybe you’d like to try your own eyes on Jacques. Start with a pair of 40mm or larger binoculars or small telescope and use the map above to help you spot it. Oh, and don’t forget to keep an exclamation mark handy when you get that first look.

Take a Look: Comet PANSTARRS K1 Swings by the Big Dipper this Week, Sprouts Second Tail

Comets often play hard to get. That’s why we enjoy those rare opportunities when they pass close to naked eye stars. For a change, they’re easy to find! That’s exactly what happens in the coming nights when the moderately bright comet C/2012 K1 PANSTARRS slides past the end of the Big Dipper’s handle. I hope Rolando Ligustri’s beautiful photo, above,  entices you roll out your telescope for a look.

Comet K5 PANSTARRS glides from northern Bootes up the handle of the Big Dipper this coming week not far from the famed Whirlpool Galaxy M51. This map shows the sky facing east (west is at top, east at bottom) with stars to magnitude +11.  Created with Chris Marriott's SkyMap software
Comet K1 PANSTARRS glides from northern Bootes up the handle of the Big Dipper this coming week not far from the bright star Alkaid and M51, the Whirlpool Galaxy. This map shows the sky facing east (west is at top, east at bottom) with stars to magnitude +11 and the comet’s position at 10 p.m. CDT daily. Click to enlarge and then print out a copy you can use at the telescope. Created with Chris Marriott’s SkyMap software

If you’ve put off viewing this fuzzball because it’s been lost in the wilds of northern Bootes too long, hesitate no more. I saw it several nights ago through a 15-inch (37-cm) scope and can report a teardrop-shaped coma with a bright, not-quite-stellar nucleus. The comet sports an 8 arc minute long faint tail (1/4 the diameter of the full moon) and glows around magnitude 9-9.5. Granted I observed from dark skies, but K1 PANSTARRS could even be seen faintly in the 10×50 finderscope, putting it within range of ordinary binoculars.

Use this map to get oriented. It shows the sky facing east around 10 o'clock in late April. The comet passes very near Alkaid on April 28-29. Stellarium
Use this map to get oriented. It shows the sky facing east around 10 o’clock in late April. The comet passes very near Alkaid on April 28-29. Stellarium

Ligustri’s photo shows both gas and dust tails, but most observers will probably pick up the dust tail and strain to see the other. The comet has been moving north and slowly waxing in brightness all winter and spring. Right now, it’s ideally placed for viewing in the early evening sky and remains up all night for northern hemisphere observers. On Monday and Tuesday April 28-29 it’s within 1 degree of Alkaid, the bright star at the end of the Dipper’s handle.

C/2012 K1 PANSTARRS, discovered with the Pan-STARRS 1 telescope high up the Haleakala volcano on  Maui, Hawaii. Credit: Carl Hergenrother
C/2012 K1 PANSTARRS, discovered in May 2012 with the Pan-STARRS 1 telescope from Hawaii, has been under observation a long time. Here on Sept. 13, 2013 it was a still a small, dim object of magnitude ~+13. Credit: Carl Hergenrother

In a 6-inch (15-cm) scope, expect to see a faint puff with a brighter core; observers with 8-inch and larger telescopes will more easily see the tail. K1 PANSTARRS continues to brighten through the spring and summer as it saunters from the Great Bear into Leo. In late July it will be too near the sun to view but re-emerge a month later in Hydra in the morning sky. Southern hemisphere skywatchers will be favored during the fall and early winter, though the comet will continue to hover very low in the southern morning sky for northerners. Predictions call for the PANSTARRS to reach peak brightness around magnitude +6 to +7 in mid-October.

Sounds like old C/2012 K1 will be around a good, long time. Why not get acquainted?

Comet ISON Heats Up, Grows New Tail

I’m starting to get the chills about Comet ISON. I can’t help it. With practically every telescope turned the comet’s way fewer than three short weeks before perihelion, every week brings new images and developments. The latest pictures show a brand new tail feature emerging from the comet’s bulbous coma. For months, amateur and professional astronomers alike have watched ISON’s slowly growing dust tail that now stretches nearly half a degree or a full moon’s diameter. In the past two days, photos taken by amateur astronomers reveal what appears to be a nascent ion or gas tail. Damian Peach’s Nov. 6 image clearly shows two spindly streamers.

Early detection of ISON's possible ion tail on Oct. 31 by amateur astronomer Efrain Morales Rivera in a 12-inch telescope.
Early detection of ISON’s possible ion tail on Oct. 31 by amateur astronomer Efrain Morales Rivera in a 12-inch telescope.

A picture of the comet two days earlier on Nov. 4 also shows new tail structures. Credit: Justin Ng
The comet on Nov. 4 also shows the new tail structures extending farther from the coma. Credit: Justin Ng

Ion tails are composed of gases like carbon monoxide and carbon dioxide  blown into a narrow straight tail by the solar wind and electrified to fluorescence by the sun’s ultraviolet light. Being made of ions (charged particles), they interact with the sun’s wind of charged particles. Changes in the intensity and direction of the magnetic field associated with sun’s exhalations kink and twist ion tails into strange shapes. Strong particle blasts can even snap off an ion tail. Not that a comet could care. Like a lizard, it grows a new one back a day or three later.

Comet ISON plunges sunward across Virgo in the coming days. Watch for it low in the eastern sky shortly before the start of dawn. Click to enlarge and print for outdoor use. Stellarium
Comet ISON plunges sunward across Virgo in the coming days. Watch for it low in the eastern sky shortly before the start of dawn. Click to enlarge and print for outdoor use. Stellarium

A fresh forked tail isn’t ISON’s only new adornment. Its inner coma, location of the bright “false nucleus”, is becoming more compact, and the overall magnitude of the comet has been slowly but steadily rising. Two mornings ago I pointed a pair of 10×50 binoculars ISON’s way and was surprised to see it glowing at magnitude 8.5.  Things happen quickly now that the comet is picking up speed  While it appeared as little more than a small smudge, any comet crossing into binocular territory is cause for excitement. Other observers are reporting magnitudes as bright as 8.0. Estimates may vary among observers, but the trend is up. Seiichi Yoshida’s excellent Weekly Information about Bright Comets site predicts another half magnitude brightening over the next few days. You can use the map here to spot it in your own glass before the moon returns to the morning sky.

Photo taken through the TRAPPIST 60-cm telescope using a narrowband CN (390 nm) filter shows two active jets in ISON's inner coma (right) and a broad dust tail at left. Credit: Cyrielle Opitom, TRAPPIST team
False color photo taken with the TRAPPIST 60-cm telescope using a narrowband CN (390 nm) filter at 8:45 Universal Time Nov. 5 shows two active jets (small double-plume) in ISON’s inner coma (right) and the dust tail at left. Field of view is 5×5 arc minutes. North is up, east to the left. Credit: Cyrielle Opitom, TRAPPIST team

But wait, there’s more. Emmanuel Jehin, a member of the TRAPPIST ( TRAnsiting Planets and PlanetesImals in Small Telescopes) team, a group of astronomers dedicated to the detection of exoplanets and the study of comets and other small solar system bodies, reports a rapid rise in ISON’s gas production rate in the past several days. They’ve increased by a factor of two since Nov. 3. Could the spike be connected to the development of an ion tail? Jehin and team have also recorded two active jets coming from the comet’s nucleus using specialized filters. Dust production rates however have remained flat.

The Comet ISON Observing Campaign is both terrestrial and celestial. Nine different NASA and ESA spacecraft, eight of which are shown here, have observed comet ISON so far. Credit: NASA/ESA
The Comet ISON Observing Campaign is both terrestrial and celestial. Nine different NASA and ESA spacecraft, eight of which are shown here, have observed comet ISON so far. Credit: NASA/ESA

Casey Lisse of the Comet ISON Observing campaign (CIOC) reports that the Chandra X-ray Observatory just became the 9th spacecraft to image the comet . More details and photos should be available soon. The campaign predicts the comet will peak in brightness between -3 to -5 magnitude when it zips closest to the sun on Nov. 28. Want to ride alongside the comet during its passage through the inner solar system? Click on this awesome, interactive simulator.

 Hubble Space Telescope image of comet C/1999 S4 (LINEAR) that disintegrated around July 23, 2000. Credit: NASA/ESA

Hubble Space Telescope image of comet C/1999 S4 (LINEAR) that disintegrated around July 23, 2000. Credit: NASA/ESA

Because ISON is a fresh-faced visitor from the distant Oort Cloud that will soon face the full fury of the sun, speculation of its fate has ranged across the spectrum. Everything from breakup and dissolution before perihelion to surviving intact trailing a spectacular dust tail. The comet is currently approaching the 0.8 A.U. mark (74.4 million miles / 120 million km) when previous comets C/1999 S4 LINEAR in 2000 and C/2010 X1 Elenin in 2011 crumbled to pieces and vaporized away. Will ISON have the internal strength to pass the test and venture further into the solar boil? Should it survive, it faces a formidable foe – the sun. Both the intense solar heat and gravitational stress on the comet’s nucleus could easily tear it apart. If this happens a few days before perihelion we’ll be left with little to see, but if ISON busts up a day or two after perihelion, watch out baby. When the comet reappears in the morning sky, it may be missing its head but make it up for the loss with a spectacular tail of fresh dust and ice many degrees in length. This is exactly what happened to Comet C/2011 W3 (Lovejoy) in December 2011. After its close graze with the home star, the nucleus disintegrated, producing a striking tail seen by skywatchers in the southern hemisphere.

Pictures of Comet C/2011 W3 Lovejoy on Dec. 22, 2011 after perihelion passage. Its head was very tiny and faint with a long tail. Credit: Chris Wyatt
Pictures of Comet C/2011 W3 Lovejoy on Dec. 22, 2011 after perihelion passage. Will ISON be a repeat? Credit: Chris Wyatt

The final scenario sees Comet ISON pushing past all barriers intact and ready to put on a splendid show. Whatever happens, I suspect we’re in for surprises ahead. For a more detailed analysis of these possibilities I invite you check out Matthew Knight’s blog on the CIOC website.