Comets Prospects for 2014: A Look Into the Crystal Ball

As 2014 opens, most of the half dozen comets traversing the morning and evening sky are faint and require detailed charts and a good-sized telescope to see and appreciate. Except for Comet Lovejoy. This gift to beginner and amateur astronomers alike keeps on giving. But wait, there’s more. Three additional binocular-bright comets will keep us busy starting this spring.

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
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

Still glowing around the naked eye limit at magnitude 6, the Lovejoy remains easy to see in binoculars from  dark skies as it tracks from southern Hercules into Ophiuchus in the coming weeks.

The best time to view the comet is shortly before the start of dawn when it 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. My last encounter with Lovejoy was a week ago when 10×50 binoculars revealed a bright coma and 1.5 degree long tail to the northwest. Through the telescope the stark contrast between bright, compact nucleus and gauzy coma struck me as one of the most beautiful sights I’d seen all month.

Path of Comet C/2012 K1 PANSTARRS this spring when it should be a nice comet for small to medium sized telescopes. Created with Chris Marriott's SkyMap software
Path of Comet C/2012 K1 PANSTARRS this spring when it should be a nice comet for small to medium sized telescopes. Created with Chris Marriott’s SkyMap software

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 PanSTARRSC/2013 V5 Oukaimeden and C/2013 A1 Siding Spring  The first lurks in Hercules but come early April should bulk up to magnitude 9.5, bright enough to track in a small telescope for northern hemisphere observers. Watch K1 PANSTARRS amble from Bootes across the Big Dipper and down through Leo from mid-spring through late June hitting magnitude 7.5 before disappearing in the summer twilight glow. K1 will be your go-to comet during convenient viewing hours.

Come early September after K1 PANSTARRS leaves the sun’s ken, it reappears in the morning sky, traveling westward from Hydra into Puppis. Southern hemisphere observers are now favored, but northerners won’t suffer too badly. The comet is expected to crest to magnitude 5.5  in mid-October just before it dips too far south for easy viewing at mid-northern latitudes.

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

Comet C/2013 V5 (Oukaimeden), discovered November 15 at Oukaimeden Observatory in Marrekesh, 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.

Comet C/2013 A1 Siding Spring is currently a faint 14th magnitude object in Eridanus. Photo taken on Dec. 30, 2013. Credit: Rolando Ligustri
Comet C/2013 A1 Siding Spring is currently a faint 14th magnitude object in Eridanus. Photo taken on Dec. 30, 2013. Credit: Rolando Ligustri

2014’s most anticipated comet has to be  C/2013 A1 Siding Spring, expected to reach magnitude 7.5 and become binocular-worthy for southern hemisphere skywatchers as it traverses the southern circumpolar constellations this September. Northerners will have to wait until early October for the comet to climb into the evening sky by way of Scorpius and Sagittarius. Watch for an 8th magnitude hazy glow in the southwestern sky at that time.

As October ticks by, A1 Siding Spring creeps closer and closer to Mars until it overlaps the planet on the 19th. Normally, a comet will only appear to pass in front of stars and deep sky objects because it’s in the same line of sight. Not this time. Siding Spring may actually “touch” Mars for real.

Comet C/2013 A1 Siding Spring will overlap Mars on October 19, 2014. With the planet at magnitude
Comet C/2013 A1 Siding Spring will overlap Mars on October 19, 2014. Assuming magnitude 8 at the time, the comet should look like a hazy glow around the planet through binoculars and telescopes. Stellarium

On October 19 the comet will pass so close to the planet that its outer coma or atmosphere may envelop Mars and spark 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.

While the list of predicted comets is skimpy and arguably not bright in the sense of headliners like Hale-Bopp in 1997 or even L4 PANSTARRS from last spring,  all should be visible in binoculars from a dark sky site.

Every year new comets are discovered, some of which can swiftly brighten and put on a great show like Comet Lovejoy (discovered Sept. 7) did last fall and continues to do. In 2013, 64 new comets were found, 14 of them by amateur astronomers. Comets with the potential to make us ooh and aah are out there –  we just have to find them.

Subaru Telescope Captures the Fine Details of Comet Lovejoy’s Tail

Comet ISON may be no more than just a cloud of icy debris these days but there’s another comet that’s showing off in the morning sky: C/2013 R1 (Lovejoy), which was discovered in September and is steadily nearing its Christmas Day perihelion. In the early hours of Dec. 3, astronomers using the 8.2-meter Subaru Telescope atop Mauna Kea in Hawaii captured this amazing image of Lovejoy, revealing the intricate flows of ion streamers in its tail. (Click the image above for extra awesomeness.)

According to a news story on the NAOJ website:

At the time of this observation, at around 5:30 am on December 3, 2013 (Hawaii Standard Time), Comet Lovejoy was 50 million miles (80 million km) distant from Earth and 80 million miles (130 million km) away from the Sun.

The entire image of comet Lovejoy was made with the Subaru Telescope’s Suprime-Cam, which uses a mosaic of ten 2048 x 4096 CCDs covering a 34′ x 27′ field of view and a pixel scale of 0.2”.

Where to find comet Lovejoy in the morning sky, Dec. 7 (via spaceweather.com)
Where to find comet Lovejoy in the morning sky, Dec. 7 (via spaceweather.com)

“Subaru Telescope offers a rare combination of large telescope aperture and a wide-field camera,” said a member of the observation team, which included astronomers from Stony Brook University in New York, Universidad Complutense in Madrid,  Johns Hopkins University, and the National Astronomical Observatory of Japan. “This enabled us to capture a detailed look at the nucleus while also photogenically framing inner portions of Comet Lovejoy’s impressive ion tail.”

Comet Lovejoy is currently visible in the early morning sky as a naked-eye object in the northern hemisphere.

Read more about Lovejoy’s journey through the inner solar system in this article by Bob King here.

Image of comet Lovejoy on Dec. 5 by Flickr user "Willo2173".
Image of comet Lovejoy on Dec. 5 by Flickr user Willo2173.

Do you have photos of comet Lovejoy or any other astronomical objects to share? Upload them to the Universe Today Flickr group!

A New Comet’s SWAN Dive Into the Sun

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A new comet has been discovered by the SOHO team, and it — like Lovejoy before it, almost three months to the day — is headed directly toward the Sun. Discovered by SOHO’s SWAN instrument, the comet has been dubbed Comet SWAN… making this a real swan dive (or, perhaps more appropriately, its swan song.)

The animation above has a lot of random noise in it from recent solar outbursts… can you spot the comet? If not, read on…

Labeled frame of the LASCO image (courtesy of SpaceWeather.com)

There’s Comet SWAN, just above the darker silhouette of the bar that holds the shielding disk over the center of the imager (which blocks the glare from the Sun itself.)

The comet is likely another member of the Kreutz family of comets, an extended family of pieces that broke off a larger comet several hundred years ago (which itself may have been a survivor of a breakup in 371 B.C.!) Comet Lovejoy was also a Kretuz sungrazer but it was considerably larger and brighter, which may have helped it survive its Dec. 15 solar close encounter to re-emerge on the opposite side, surprising astronomers everywhere!

Read how some scientists think Comet Lovejoy held itself together.

SWAN may not be so lucky… but then again, we’ve been surprised before!

The comet will make perihelion — its closest approach to the Sun — on March 14. Stay tuned for more details!

Images via SpaceWeather.com.

How Did Comet Lovejoy Survive Its Trip Around The Sun?

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It was just about three months ago that the astronomy world watched in awe as the recently-discovered comet Lovejoy plummeted toward the Sun on what was expected to be its final voyage, only to reappear on the other side seemingly unscathed! Surviving its solar visit, Lovejoy headed back out into the solar system, displaying a brand-new tail for skywatchers in southern parts of the world (and for a few select viewers above the world as well.)

How did a loosely-packed ball of ice and rock manage to withstand such a close pass through the Sun’s blazing corona, when all expectations were that it would disintegrate and fizzle away? A few researchers from Germany have an idea.

Scientists from the Max Planck Institute for Extraterrestrial Physics and the Braunschweig University of Technology have hypothesized that Comet Lovejoy managed to hold itself together through the very process that, to most people, defines a comet: the outgassing of sublimated icy material.

As a comet near the Sun, the increased heating from solar radiation causes the frozen materials within the nucleus to sublimate — go directly and suddenly from solid to gas, skipping the liquid middle stage — and, in doing so, burst through the surface of the comet and create the long, hazy reflective tail that is so often associated with them.

Overview of the forces acting on sungrazing comets. (Illustration from paper.)

In the case of Lovejoy, which was on a direct path toward the Sun, the sublimation itself may have provided enough outward force across its surface to literally keep it together, according to the team’s research.

“The reaction force caused by the strong outgassing (sublimation) of the nucleus near the Sun acts to keep the nucleus together and to overcome the tidal disruption,” the paper claims.

In addition, the team states that the size of the comet’s nucleus can be derived using an equation that takes into consideration the combined forces of outgassing, the material composition of the comet’s nucleus, the comet’s own gravity and the tidal forces exerted by the comet’s close proximity to the Sun (i.e., the Roche limit).

Using that equation, the team concluded that the diameter of Comet Lovejoy’s nucleus is anywhere between 0.2 km and 11 km (.125 miles and 6.8 miles). Any smaller and it would have lost too much material during its pass (and had too little gravity); any larger and it would have been too thick for outgassing to provide enough counterbalancing force.

If this hypothesis is correct, taking a trip around the Sun may not mean the end for all comets… at least not those of a certain size!

Watch the video of Lovejoy’s Dec. 15 solar swing below:

The paper was submitted to the journal Icarus on March 8, 2012 by Bastian Gundlach. See the full text here.

ISS Soars Over Stormy Africa


Here’s a quick but lovely little gem: a time-lapse video taken from the ISS as it passed above central Africa, Madagascar and the southern Indian Ocean on December 29, 2011. The nighttime flyover shows numerous lightning storms and the thin band of our atmosphere, with a layer of airglow above, set against a stunning backdrop of the Milky Way and a barely-visible Comet Lovejoy, just two weeks after its close encounter with the Sun.

This video was made from photos taken by Expedition 30 astronauts. The photos were compiled at Johnson Space Center and uploaded to The Gateway to Astronaut Photography of Earth, an excellent database of… well, of astronauts’ photos of Earth.

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The site’s description of this particular video states:

This video was taken by the crew of Expedition 30 on board the International Space Station. The sequence of shots was taken December 29, 2011 from 20:55:05 to 21:14:09 GMT, on a pass from over central Africa, near southeast Niger, to the South Indian Ocean, southeast of Madagascar. The complete pass is over southern Africa to the ocean, focusing on the lightning flashes from local storms and the Milky Way rising over the horizon. The Milky Way can be spotted as a hazy band of white light at the beginning of the video. The pass continues southeast toward the Mozambique Channel and Madagascar. The Lovejoy Comet can be seen very faintly near the Milky Way. The pass ends as the sun is rising over the dark ocean.

There are lots more time-lapse videos on the Gateway as well, updated periodically. Check them out here.

Video courtesy of the Image Science & Analysis Laboratory, NASA Johnson Space Center.