Comet K1 PanSTARRS: See It Now Before it Heads South

Credit:

Comet C/2012 K1 PanSTARRS, one of the most dependable comets of 2014, may put on its encore performance over the coming weeks for southern hemisphere observers.

First, the story thus far. Discovered as a +19th magnitude smudge along the borders of the constellations Ophiuchus and Hercules in mid-May 2012 courtesy of the Panoramic Survey Telescope And Rapid Response System (PanSTARRS) based atop Haleakala on the Hawaiian island of Maui, astronomers soon realized that comet C/2012 K1 PanSTARRS would be something special.

The comet broke +10th magnitude to become a visible binocular object in early 2014, and wowed northern hemisphere observers as it vaulted across the constellations of Boötes and Ursa Major this past spring.

NEOWISE
NASA’s NEOWISE mission spies K1 PanSTARRS on May 20th as it slides by the galaxy NGC 3726 (blue). Credit: NASA/JPL.

The comet is approaching the inner solar system on a retrograde, highly-inclined orbit tilted 142 degrees relative the ecliptic. This bizarre orbit also assures that the comet will actually reach opposition twice in 2014 as seen from our earthly vantage point: once on April 15th, and another opposition coming right up on November 7th.

As was the case with comet Hale-Bopp way back in 1997, had C/2012 K1 PanSTARRS arrived six months earlier or later, we would’ve been in for a truly spectacular show, as the comet reached perihelion on August 27th, 2014, only 0.05 A.U.s (4.6 million miles or 7.7 million kilometres) outside the orbit of the Earth! But such a spectacle was not to be… back in ’97, Hale-Bopp’s enormous size — featuring a nucleus estimated 40 to 60 kilometres across — made for a grand show regardless… fast forward to 2014, and the tinier nucleus of K1 PanSTARRS has been relegated to binocular status only.

Credit
The position of comet K1 PanSTARRS as it passes its second opposition of the year. Credit: NASA/JPL.

From here on out, K1 PanSTARRS is headed south “with a bullet” and into memory for most northern hemisphere observers. We spied the comet this morning low to the south near +3rd magnitude Nu Puppis in the pre-dawn sky with our trusty 15×45 binocs from Yuma, Arizona, for what will probably be our last time. This also means that the time to catch a last glimpse of K1 PanSTARRS for northern hemisphere viewers is now. This week sees the comet transiting just 20 degrees above the southern horizon at 3:00 to 4:00 AM local for observers based from latitude 30 degrees north as it crosses the constellation Puppis. The bright star Sirius nearly shares the same position as the comet in right ascension this week, and K1 PanSTARRS sits about 24 degrees south of the Dog Star.

K1 PanSTARRS jaicoa
Comet K1 PanSTARRS imaged on June 14th. Credit: Efrain Morales.

Halloween sees the comet even lower, crossing the southern meridian at only 13 degrees elevation as seen from latitude 30 degrees north. Draw a straight line from Sirius to the south celestial pole around this date to find the comet just 5 degrees to the north of Canopus.

But the show is just beginning for southern hemisphere residents. Observing from the town of Bright Australia, Robert Kaufmann recently noted in a posting on the Yahoo Groups Comet Observer’s message board that the comet currently exhibits a 4’ wide coma shining at about magnitude +7.3 with an elevation of 28 degrees above the horizon on October 25th.

And if the comet holds steady in brightness, it may break the visual threshold and become a naked eye object as seen from a dark sky site in early November.

Light curve
The projected light curve of K1 PanSTARRS with brightness observations (black dots). The vertical pink line marks the comet’s perihelion passage in late August. Credit: Seiichi Yoshida’s Weekly Information on Bright Comets.

The comet will be literally “hauling tail” across the constellation Dorado as it nears its second opposition of the year on November 7th, moving about 1.5 degrees a day – 3 times the apparent diameter of the Full Moon – on closest approach.

Currently, the comet has been observed to have an estimated magnitude holding steady at+7 and is predicted to peak at perhaps magnitude +6 early next month. And while it would’ve been great had it arrived 6 months earlier or later, the aforementioned high retrograde inclination of its orbit assured that K1 PanSTARRS was a top performer for both hemispheres in 2014.

Perihelion passage occurred two months ago, but to paraphrase a famous Monty Python skit, Comet K1 PanSTARRS is “not dead yet.”  Here are some key observing dates coming right up as the comet gains prominence in the southern hemisphere sky:

(Note that close passages of less than one degree near stars +4th magnitude or brighter only are mentioned).

Oct 31st: Passes closest to Earth, at 0.953 A.U.s distant.

Nov 1st: Crosses into the constellation Pictor.

Nov 2nd: Passes near the +3.8 magnitude star Beta Pictoris.

Nov 6th: Crosses into the constellation Dorado.

Nov 6th: Full Moon occurs, marking the beginning of an unfavorable week for comet hunting.

Nov 7th: The second opposition of the comet for 2014 occurs at 3:00 UT.

Nov 8th: Passes near the +3.3 magnitude star Alpha Doradus.

Nov 11th: Crosses into the constellation Reticulum.

Nov 13th: Crosses into the constellation Horologium.

Nov 14th: Passes 34 degrees from the South Celestial Pole.

Nov 20th: Crosses into the constellation Eridanus.

Nov 22nd: New Moon occurs, marking a week long span optimal for comet-hunting.

Nov 25th: Crosses into the constellation Phoenix.

Starry Night Education Software.
The path of K1 PanSTARRS from October 27th through December 1st. Created by the author using Starry Night Education Software.

Dec 6th: Full Moon occurs.

Dec 12th: Passes near the +2.8 magnitude star Alpha Phoenicis (Ankaa).

Dec 18th: Crosses into the constellation Sculptor.

Dec 22nd: New Moon occurs.

Looking at 2015, K1 PanSTARRS will probably fall back below +10th magnitude by late January. The comet will then head back out into the depths of the outer solar system, its multi-million year orbit only slightly altered by its inner solar system passage down into the ~700,000 year range. What will Earth be like on that far off date? Will human eyes greet the comet once again, and will anyone remember its appearance way back in the mists of time in 2014? All thoughts to ponder as we bid fair well to Comet C/2012 K1 PanSTARRS, a fine binocular comet indeed.

 

Comet PANSTARRS: The Show’s Not Over Yet!

Comet PANSTARRS as seen over Payson, Arizona on April 24, 2013. Credit and copyright: Chris Schur

While Comet C/2011 L4 (PANSTARRS) is fading to barely naked-eye and binocular visibility (the comet has lost a full magnitude approximately every week since perihelion on March 9), astrophotographers are still able to track down the comet as it moves away from the Sun. This deep color exposure by Chris Schur in Arizona is still able to show surprising detail and Chris said via email that he was “surprised how beautifully colored the stars are in this part of the Milky Way.” Chris’s shot is a 25 minute exposure, and is an LRGB (Luminance, Red, Green and Blue — is a photographic technique used in amateur astronomy for producing good quality color photographs by combining a high-quality black-and-white image with a color image).

See some more recent PANSTARRS images from around the world, below, plus an awesome new timelapse from TWAN (The World At Night) photographer P-M Hedén:

The Visitor – Comet PanStarrs from P-M Hedén on Vimeo.

Comet C/2011 L4 (PANSTARRS) on April 23, 2013. Credit and copyright:  Paul M. Hutchinson.
Comet C/2011 L4 (PANSTARRS) on April 23, 2013. Credit and copyright: Paul M. Hutchinson.
Comet PANSTARRS and star trails on April 21, 2013. Credit and copyright: David G. Strange.
Comet PANSTARRS and star trails on April 21, 2013. Credit and copyright: David G. Strange.
Comet C/2011 L4 PanSTARRS in false color, 'sigma combined and rotational gradient filter (inset) C8 @ f/2 85mins. exposure. April 19, 2013. Credit and copyright: David G. Strange.
Comet C/2011 L4 PanSTARRS in false color, ‘sigma combined and rotational gradient filter (inset) C8 @ f/2 85mins. exposure. April 19, 2013. Credit and copyright: David G. Strange.
Comet C.2011 L4 (PANSTARRS) on April 15, 2013. A 5 minute exposure with a Zeiss 80mm astrograph with DSLR camera. Credit and copyright: Chris Schur.
Comet C.2011 L4 (PANSTARRS) on April 15, 2013. A 5 minute exposure with a Zeiss 80mm astrograph with DSLR camera. Credit and copyright: Chris Schur.

This shot was taken on April 2 when Comet PANSTARRS was snuggling up in the sky with the Andromeda Galaxy, but this beautiful image is a recent addition to Universe Today’s Flickr page. You can see more images of PANSTARRS and the Andromeda Galaxy here and here.

13 frame stack of Comet PanSTARRS and the Andromedaa Galaxy on April 2, 2013 as seen over Leitrim, Ireland. Canon 200mm. Credit and copyright: Martin Campbell.
13 frame stack of Comet PanSTARRS and the Andromedaa Galaxy on April 2, 2013 as seen over Leitrim, Ireland. Canon 200mm. Credit and copyright: Martin Campbell.

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Comet PANSTARRS … Going … Going … Not Gone Yet!

Comet C/2011 L4 PANSTARRS on the evening of April 9, 2013 from Austria. Dust released when the sun vaporizes the comet's ice is pushed back by the pressure of sunlight to form the tail. Click to enlarge. Credit: Michael Jaeger

It’s falling out of the news but Comet PANSTARRS still lives! You can still see it in a clear sky near you with nothing more than a pair of binoculars. And thanks to guidance from the bright zigzag of Cassiopeia, it’s easier than ever to find. Would that we had had this star group to point up comet-ward in March when PANSTARRS was brightest!

The comet marches along through Cassiopeia the Queen in April. The map shows the sky facing northwest about 90 minutes after sunset. Comet positions are shown every 5 nights. Stellarium
The comet marches along through Cassiopeia the Queen in April. The map shows the evening sky facing northwest about 90 minutes after sunset. Comet positions are shown every 5 nights. Stellarium

Start looking about 75-90 minutes after sunset or the same amount of time before sunrise. Yes, the comet is visible now at both dusk and dawn. Currently it shines at about 4.5-5 magnitude and might still be faintly visible with the naked from a very dark sky location. In 35-50mm binoculars it will look like a faint, fuzzy streak of light with a brighter head. Telescopes still give a wonderful view of the bright nucleus and shapely tail.

While the northern U.S., Canada and Europe have good views of PANSTARRS at both dusk and dawn, sky watchers in the southern U.S. have their best views at dawn. This map shows the sky facing northeast about 90 minutes before sunrise. Stellarium
While the northern U.S., Canada and Europe have good views of PANSTARRS at both dusk and dawn, sky watchers in the southern U.S. have their best views at dawn. This map shows the sky at the start of dawn facing northeast about 90 minutes before sunrise. Stellarium

The other night a student who helps run our local planetarium described it as looking like a “real comet” through the telescope, the way textbook and online photos had led him to anticipate. Binoculars or telescope will show a misty, plume-like tail, but wide-field, time-exposure photography reveals the comet’s unbelievably broad fan of dust.

Comet PANSTARRS moves along a steeply tilted orbit that takes it far above and below the plane of the planets. Right now it’s high above Earth’s north pole and we see its tail broadside. The comet takes about 106,000 years to complete an orbit around the sun. Credit: NASA/JPL/Bob King
Comet PANSTARRS moves along a steeply tilted orbit that takes it far above and below the plane of the planets. Right now it’s high above Earth’s north pole and we see its tail broadside. The comet takes about 106,000 years to complete an orbit around the sun. Credit: NASA/JPL/Bob King

The reason for this unusual appearance has much to do with perspective. PANSTARRS is sailing back into deep space directly above the plane of the planets. With the tail blown back by the pressure of sunlight, we look up and across a distance of more than 125 million miles (201 million km) to see it spread like a deck of cards across the constellation Cassiopeia.

Comet PANSTARRS a week ago when it passed near the Andromeda Galaxy (at left). Details: 300mm f/2.8, ISO 800 and 90-second exposure. Credit: Bob King
Comet PANSTARRS a week ago when it passed near the Andromeda Galaxy (at left). Details: 300mm f/2.8, ISO 800 and 90-second exposure. Credit: Bob King

In the northern U.S., Cassiopeia is higher up in both morning and evening skies and easy to spot. Once you’ve found its familiar shape, focus your binoculars on the brightest star nearest the comet, and slowly work your way in its direction. Skywatchers in the northern U.S., Canada and Europe are favored because Cassiopeia is a northern constellation and higher up in the sky at both dusk and dawn. Observers in the southern U.S. will get their best views around the start of dawn.

A Detailed Look at the Coma of Comet PANSTARRS

Image and variations of Comet C/2011 L4 (PANSTARRS) taken on 2013, April 7, 2013 remotely from New Mexico. Credit: Ernesto Guido, Nick Howes, and Martino Nicolini.

Comet PANSTARRS has peaked, but astronomers are still keeping an eye on this comet to try and determine what its future might hold. The team from the Remanzacco Observatory has just produced some really interesting views of Comet PANSTARRS, with a little help from Martino Nicolini and his Astroart software.

Team member Nick Howes called this software “one of the best astronomical image processing and acquisition tools around,” and explained how these views can tell astronomers more about what is happening with the comet.

“The isophotes image (color coded) is a good way to see the morphology/structure of the coma,” he told Universe Today, adding that comparing the images here is “a very good way to determine any major events like a fragmentation. We’re hopeful that once PANSTARRS gets a bit higher, we’ll be able to look at it in even more detail with the 2 meter Faulkes scopes.

And with the image processing in the image on the far right, it’s possible to see a bright shell in the coma of comet C/2011 L4 (PANSTARRS).

“The last elaboration in that image has been obtained using the M.C.M. (Median Coma Model), a filter that has the purpose of creating — from an image of a comet — a synthetic model of the ‘regular’ coma,” said Ernesto Guido, from the Remanzacco team. “That is obtained by mapping all the pixels that compose the image and averaging them together. In doing so we delete all the morphological “non-uniformity” contained in the coma itself. This regular coma will then be subtracted from the original image highlighting all the details that are normally immersed in the uniform brightness of the coma.”

Check out the Remanzacco website for more information and their continued updates.

Was the Repeating Passage of Halley’s Comet Known of in Ancient Times?

Comet P/Halley as seen on its last inner solar system passage on March 8th, 1986. (Credit: W. Liller/NASA GSFC/ International Halley Watch Large Scale Phenomena Network).

An interesting and largely unknown tale of ancient astronomy recently came our way while reading author and astrophysicist Mario Livio’s blog. The story involves the passage of the most famous of all comets.  

It’s fascinating to consider ancient knowledge of the skies. While our knowledge of ancient astronomy is often sparse, we know that cultures lived and perished by carefully monitoring the passage of the heavens.  A heliacal rising of Sirius might coincide with the impending flooding of the life-giving waters of the Nile, or the tracking of the solstices and equinoxes might mark the start of the seasons.

To the ancients, comets were “hairy stars” which appeared unpredictably in the sky. We generally attribute the first realization that comets are periodic to Sir Edmond Halley, who successfully utilized Newton’s laws of gravity and Kepler’s laws of planetary motion to predict the return of Halley’s Comet in 1758. Such a prediction was a vindication of science.

But an interesting tale comes to us from the 1st century CE that Rabbi & Jewish Scholar Yehoshua Ben Hananiah may have known something of “a star that appears every 70 years.” The tale, as told in the Horayoth (rulings) of the Talmud and described in Mr. Livio’s blog is intriguing:

Rabbi Gamliel and Rabbi Yehoshua went together on a voyage at sea. Rabbi Gamliel carried a supply of bread. Rabbi Yehoshua carried a similar amount of bread and in addition a reserve of flour. At sea, they used up the entire supply of bread and had to utilize Rabbi Yehoshua’s flour reserve. Rabbi Gamliel then asked Rabbi Yehoshua: “Did you know that this trip would be longer than usual, when you decided to carry this flour reserve?” Rabbi Yehoshua answered: “There is a star that appears every 70 years and induces navigation errors. I thought it might appear and cause us to go astray.”   

The Rabbi’s assertion is a fascinating one. There aren’t a whole lot of astronomical phenomena on 70 cycles that would have been noticeable to ancient astronomers. With an orbital period of 75.3 years, Halley’s Comet seems to fit the bill the best. The earliest confirmed description of Halley’s comes from Chinese astronomers during its 240 BCE passage. Later subsequent passages of the comet through the inner solar system were noted by the Babylonians in 164 & 87 BCE.

Of course, there’s no further evidence that ancient scholars identified those passages as the same comet. Some great comets such as Hale-Bopp seen in 1997 and this year’s anticipated Comet C/2012 S1 ISON are on orbits spanning thousands of years that outlast most Earthly civilizations.

Mr. Livio also notes that historical knowledge of ancient apparitions of Halley’s may have been accessible to the Great Knesset scholars during the Babylonian exile of the 6th century BCE.

One of the chief objections raised to the Halley hypothesis is the circumstances of the appearance of Halley’s Comet in the Rabbi’s lifetime. Remember, most folks didn’t live for 70 years in the 1st century. Any tales of a periodic comet would have been handed down by generations. You would be lucky to see Halley’s Comet once in your lifetime. Plus, not all apparitions of Halley’s Comet are favorable. For example, Halley’s was bright enough to induce “comet hysteria” with the public in 1910. In contrast, few northern hemisphere members of the general public got a good view of it during its 1986 passage.

Medieval woodcut depicting the supposed destructive influence of a 4th century comet. (Credit: Stanilaus Lubienietski's Theatrum Cometicum, Amsterdam 1668).
Medieval woodcut depicting the supposed destructive influence of a 4th century comet. (Credit: Stanilaus Lubienietski’s Theatrum Cometicum, Amsterdam 1668).

Halley’s Comet was visible on and around January 25th, 66 CE during the Rabbi’s lifetime. However, the Rabbi would have been in his 20’s and have been a student (and not yet a Rabbi) himself. One can imagine that if he was fearful of a “false star” leading them astray, he must’ve known that the 70 year period was just about neigh.

The 66 CE apparition of Halley’s Comet would have appeared around the time of the Jewish Rebellion and just four years before the destruction of the Second Temple in Jerusalem by the Romans in 70 CE.

One other possible astronomical culprit has been cited over the years. The classic variable star Mira (Omicron Ceti) currently has a 332 day cycle which ranges from magnitude +3.5 to below naked eye visibility at +8.6 to +10.1. The variability of Mira was first discovered by astronomer David Fabricius on August 3rd 1596. There are suggestions that ancient Chinese and Babylonian astronomers may have known of this “vanishing star”.

The variable star Mira as imaged by the Hubble Space Telescope. (Credit: NASA/STScl/Margarita Karovska at the Harvard-Smithsonian Center for Astrophysics).
The variable star Mira as imaged by the Hubble Space Telescope. (Credit: NASA/STScl/Margarita Karovska at the Harvard-Smithsonian Center for Astrophysics).

Mira is expected to reach maximum for 2013 from July 21st to 31st.

Not all maxima for Mira are of equal brightness. Mira can peak anywhere from magnitude +2.0 to +4.9 (a 15-fold difference) and there’s evidence to suggest it may have been brighter in the past. Astronomer Philippe Veron noted in 1982 that a larger oscillation period of 60 years for the peak maxima of Mira falls just a decade short of Rabbi Yehoshua’s mention of an errant star.

Whatever the case, its fascinating to consider what celestial object might’ve been referred to, and how many other astronomical tales might be awaiting discovery in ancient texts. We’ve got lots of comets to ponder this year as Comet PanSTARRS, Lemmon, and ISON grace our skies in 2013. Halley’s will make its next visit to the inner solar system in 2061. I’ll open it up to you, the astute Universe Today reading public; was the Rabbi’s Star a comet, a variable star, a meteor storm, or none of the above?

Halley's Comet as seen from latitude 30 north on the morning of July 31st, 2061. (Created by the author using Starry Night software).
Halley’s Comet as seen from latitude 30 north on the morning of July 31st, 2061. (Created by the author using Starry Night software).

-Dr. Mario Livio blogs at A Curious Mind. Be sure to check out his new book Brilliant Blunders: From Darwin to Einstein – Colossal Mistakes by Great Scientists That Changed Our Understanding of Life in the Universe out on May 14th!

 

Comet PANSTARRS Meets the Andromeda Galaxy — More Amazing Images

Comet PANSTARRS and M31 on April 4, 2013, as seen from Sweden. Credit and copyright: Göran Strand.

More of our readers had success in capturing the awesomeness of seeing Comet PANSTARRS encounter the Andromeda Galaxy (M31) in the night sky. Göran Strand sent us this absolutely gorgeous image, taken from 70 km north of Östersund, Sweden — a really dark site with no light pollution. “This photo is a 30 minute exposure through my 300mm/f2.8 lens using my full format Nikon D3s camera,” Göran said. “Besides seeing the comet and the galaxy, I also got to see 4 elks, 2 meteors, 1 bolide and 1 aurora. So all in all, it was a good night!”

That’s for sure!

See more images below of this great meet-up in the skies, and see our earlier post of our readers’ images here.

Comet C/2011 L4 Panstarrs and the Andromeda Galaxy: Two Frame Mosaic from New Mexico Skies, April 4, 2013. Taken from New Mexico Skies at 23:22  UT using an FSQ 10.6-cm and STL11K camera.  Credit and copyright: Joseph Brimacombe.
Comet C/2011 L4 Panstarrs and the Andromeda Galaxy: Two Frame Mosaic from New Mexico Skies, April 4, 2013.
Taken from New Mexico Skies at 23:22 UT using an FSQ 10.6-cm and STL11K camera. Credit and copyright: Joseph Brimacombe.
The encounter between Comet PANSTARRS and the Andromeda Galaxy, as seen from Ireland. 'A difficult image to capture due to low cloud, the low altitude of the target and tracking Issue.'  Image details: Date: 03 Apr 2013, 22:30-23:30 Exposure: 9 x 5min, ISO 1600, F5, 6 x dark frames, 6 x flats frames. Equipment: Canon 1000D, CG5 Mount, Sigma 70-300mm set at 200mm. Credit and copyright: Brendan Alexander.
The encounter between Comet PANSTARRS and the Andromeda Galaxy, as seen from Ireland. ‘A difficult image to capture due to low cloud, the low altitude of the target and tracking Issue.’ Image details: Date: 03 Apr 2013, 22:30-23:30
Exposure: 9 x 5min, ISO 1600, F5, 6 x dark frames, 6 x flats frames.
Equipment: Canon 1000D, CG5 Mount, Sigma 70-300mm set at 200mm. Credit and copyright: Brendan Alexander.
Comet PANSTARRS and M31 taken from the Scottish Dark Sky Observatory on April 3, 2013. Credit and copyright: Dave Hancox via Google+.
Comet PANSTARRS and M31 taken from the Scottish Dark Sky Observatory on April 3, 2013. Credit and copyright: Dave Hancox via Google+.
Comet C/2011 L4 (PANSTARRS) and M31 (Andromeda Galaxy) taken from just outside St Clears, Carmarthenshire, Wales on 29th March 2013 around 9pm. Credit and copyright: Pete Newman.
Comet C/2011 L4 (PANSTARRS) and M31 (Andromeda Galaxy) taken from just outside St Clears, Carmarthenshire, Wales on 29th March 2013 around 9pm. Credit and copyright: Pete Newman.

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Incredible Views: Comet PANSTARRS Meets the Andromeda Galaxy

Two objects 2.5 million lightyears apart... PanSTARRS & Andromeda. Credit and copyright: Brendan Alexander.

We warned you it was going to happen, and here’s visual proof! In this comet encounter of the extragalactic kind, Comet PanSTARRS and the Andromeda Galaxy met each other in the skies above Earth. This great image by Brendan Alexander in Ireland shows the spectacular view. He said it was “a difficult image to capture due to low cloud, the low altitude of the target and tracking issue. I hope to get the chance to improve on this!”

Here’s another image from UT reader Anna Morris:


Comet PANSTARRS and the Andromeda galaxy over Suffolk, England on April 2, 2013. This composite images shows the movement of the comet during the imaging session. Credit and copyright: Anna Morris.
Comet PANSTARRS and the Andromeda galaxy over Suffolk, England on April 2, 2013. This composite images shows the movement of the comet during the imaging session. Credit and copyright: Anna Morris.

Want to see this meetup for yourself? Tonight might be even better:

Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet.  The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium
Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet. The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium

Did you capture this event, too? Let us know, or upload your images to our Flickr page.

Comet Lemmon: A Preview Guide for April

Comet C/2012 F6 Lemmon as imaged by Luis Argerich as from near Buenos Aires, Argentina on March (Credit: Nightscape photography. Used with permission).

As Comet 2011 L4 PanSTARRS moves out of the inner solar system, we’ve got another comet coming into view this month for northern hemisphere observers. 

Comet C/2012 F6 Lemmon is set to become a binocular object low to the southeast at dawn for low northern latitudes in the first week of April. And no, this isn’t an April Fools’ Day hoax, despite the comet’s name. Comet Lemmon (with two m’s) was discovered by the Mount Lemmon Sky Survey (MLSS) based outside of Tucson, Arizona on March 23, 2012. MLSS is part of the Catalina Sky Survey which searches for Near Earth Asteroids. We’ve got another comet coming into view this month for northern hemisphere observers as Comet 2011 L4 PanSTARRS moves out of the inner solar system.

The comet is on an extremely long elliptical orbit, with a period of over 11,000 years. Comet Lemmon just passed perihelion at 0.74 astronomical units from the Sun on March 24th.

Animation of Comet Lemmon as it passes the star Gamma Crucis on January 17th. (Courtesy of Luis Argerich. Used with permission).
Animation of Comet Lemmon as it passes the star Gamma Crucis on January 17th. (Courtesy of Luis Argerich. Used with permission).

Southern hemisphere observers have been getting some great views of Comet Lemmon since the beginning of this year. It passed only three degrees from the south celestial pole on February 5th, and since that time has been racing up the “0 Hour” line in right ascension. If that location sounds familiar, that’s because another notable comet, 2011 L4 PanSTARRS has been doing the same. In fact, astrophotographers in the southern hemisphere were able to catch both comets in the same field of view last month.

Another celestial body occupies 0 Hour neighborhood this time of year. The Sun just passed the vernal equinox marking the start of Spring in the northern hemisphere and Fall in the southern on March 19th.

And like PanSTARRS, Comet Lemmon has a very steep orbit inclined 82.6° relative to the ecliptic.

The steep path and current position of Comet Lemmon. (Credit: NASA/JPL' Small-Body Database Browser).
The steep path and current position of Comet Lemmon. (Credit: NASA/JPL’ Small-Body Database Browser).

Comet Lemmon broke naked-eye visibility reaching +6th magnitude in late February and has thus far closely matched expectations. Current reports place it at magnitude +4 to +5 as it crosses northward through the constellation Cetus. Predictions place the maximum post-perihelion brightness between magnitudes +3 and +5 in early April, and thus far, Comet Lemmon seems to be performing right down the middle of this range.

Brightness graph for Comet Lemmon for the months surrounding perihelion. (Created by author).
Brightness graph for Comet Lemmon for the months surrounding perihelion. (Created by author).

Southern observers have caught a diffuse greenish 30” in diameter nucleus on time exposures accompanied by a short, spikey tail. Keep in mind, the quoted brightness of a comet is extended over its entire surface area. Thus, while a +4th magnitude star may be easily visible in the dawn, a 3rd or even 2nd magnitude comet may be invisible to the unaided eye. Anyone who attempted to spot Comet PanSTARRS in the dusk last month knows how notoriously fickle it actually was. Binoculars are your friend in this endeavor. Begin slowly sweeping the southeast horizon about an hour before local sunrise looking for a fuzzy “star” that refuses to reach focus. Comet Lemmon will get progressively easier in the dawn sky for latitudes successively farther north as the month of April progresses.

The apparent path of Comet Lemmon for April looking southeast about an hour before local sunrise from latitude 30 degrees north. (Created by the Author using Starry Night).
The apparent path of Comet Lemmon for April 10th through the 30th looking east about an hour before local sunrise from latitude 30 degrees north. (Created by the Author using Starry Night).

Comet Lemmon will continue to gain elevation as it crosses from Cetus into the constellation Pisces on April 13th. An interesting grouping occurs as the planet Mercury passes only a few degrees from the comet from April 15th to April 17th. Having just past greatest elongation on March 31st, Mercury will shine at magnitude -0.1 and make a good guide to locate the comet in brightening dawn skies. The pair is joined by the waning crescent Moon on the mornings of April 7th and 8th which may also provide for the first sighting opportunities from low north latitudes around these dates.

The apparent path of Comet Lemmon for April looking southeast about an hour before local sunrise from latitude 30 degrees north. (Created by the Author using Starry Night).
Mercury meets Comet Lemmon on April 15th as seen about an hour before local sunrise from latitude 30 degrees north. (Created by the Author using Starry Night).

The Moon reaches New phase on Wednesday, April 10th at 5:35AM EDT/9:35 UT. It will be out of the morning sky for the next couple of weeks until it reaches Full on April 25th, at which point it will undergo the first eclipse of 2013, a very shallow partial. (More on that later this month!)

Comet Lemmon will then slide across the celestial equator on April 20th and cross the plane of the ecliptic on April 22nd as it heads up into the constellation Andromeda in mid-May. We’re expecting Comet Lemmon to be a fine binocular object for late April, but perhaps not as widely observed due to its morning position as PanSTARRS was in the dusk.

By mid-May, Comet Lemmon will have dipped back down below +6th magnitude and faded out of interest to all but a few deep sky enthusiasts. Comet Lemmon will pass within 10° of the north celestial pole on August 9th, headed back out into the icy depths of the solar system not to return for another 11,000-odd years.

It’s interesting to see how these two springtime comets will effect observers expectations for the passage of Comet C/2012 S1 ISON. Will this in fact be the touted “Comet of the Century?” Much hinges on whether ISON survives its November 28th perihelion only 1,166,000 kilometers from the center of our Sun (that’s 0.68 solar-radii or about 3 times the Earth-Moon distance from the surface of the Sun). If so, we could be in for a fine “Christmas Comet” rivaling the passage of Comet Lovejoy in late 2011. On the other hand, a disintegration of Comet ISON would be more akin to the fizzle of Comet Elenin earlier in 2011.

In the meantime, enjoy Comet Lemmon as an Act 2 in the 2013 Three Act “Year of the Comet!

Stunning Vistas: Comet PANSTARRS Meets the Aurora

The northern lights or aurora borealis swirls over a fjord in the Norwegian Sea near Tromso, northern Norway. A mix of moonlight, aurora, and a nearby village illuminate the landscape. The Pleiades Star Cluster (the Seven Sisters) appears on the upper left. Credit and copyright: Babek A. Tafreshi.

I’m completely envious of this view! Not only is there a stunning winter vista of mountains and a fjord near Tromso, Norway, but in the peaceful evening twilight, Comet PanSTARRS (C/2011 L4) shows up. To top off the view, a sudden burst of aurora borealis makes an appearance! This view was captured by Babak Tafreshi on March 20, 2013.

See some of his stunning images below:

Click on each of the images for a larger view at Tafreshi’s website.

The northern lights or aurora borealis dances over a fjord mountains near Tromso, northern Norway. A mix of moonlight, aurora, and a nearby village illuminate the the landscape. Bright planet Jupiter and the Pleiades Star Cluster (the Seven Sisters) appear over the mountains. Credit and copyright: Babak A. Tafreshi.
The northern lights or aurora borealis dances over a fjord mountains near Tromso, northern Norway. A mix of moonlight, aurora, and a nearby village illuminate the the landscape. Bright planet Jupiter and the Pleiades Star Cluster (the Seven Sisters) appear over the mountains. Credit and copyright: Babak A. Tafreshi.
A fisheye view of the northern lights as it swirls over a fjord in the Norwegian Sea near Tromso, northern Norway. A mix of moonlight, aurora, and a nearby village illuminates the the landscape. Credit: Babak A. Tafreshi.
A fisheye view of the northern lights as it swirls over a fjord in the Norwegian Sea near Tromso, northern Norway. A mix of moonlight, aurora, and a nearby village illuminates the the landscape. Credit: Babak A. Tafreshi.

Comet and the Northern Lights from Babak Tafreshi on Vimeo.

Comet PANSTARRS En Route To Andromeda Galaxy Encounter

Comet C/2011 L4 Panstarrs, taken from New Mexico Skies between on March 25, 2013 using an FSQ 10.6 and STL11K camera. 65 frames over 18 min each with an exposure time of 2.0 sec. The stars have been enhanced for effect. Credit and copyright: Joseph Brimacombe.

Get ready for an comet encounter of the extragalactic kind. In less than a week, Comet PANSTARRS will slide by the Andromeda Galaxy, the brightest galaxy visible in northern hemisphere skies. On and around that date, you’ll be able to see them both glowing softly together in late evening and early morning twilight.

The Andromeda Galaxy is the closest large galaxy to our Milky Way. It's easily visible in binoculars in the constellation Andromeda. Credit: Adam Evans
The Andromeda Galaxy is the closest large galaxy to our Milky Way. It’s easily visible in binoculars in the constellation Andromeda. Credit: Adam Evans

Their apparent proximity if of course pure sleight of hand; the comet will be a mere 121 million miles (195 million km) from Earth on that date compared to Andromeda’s 2.5 billion light years. For what it’s worth, 121 million miles (195 million km) equates to 0.00002 light years. Let’s just say they’re WAY far apart in reality. Their juxtaposition will make for enjoyable binocular viewing as well as offer astrophotographers an opportunity to create a classic image.

Comet PANSTARRS on March 22 photographed with a 200mm lens at dusk on a motorized tracking platform. Credit: Bob King
Comet PANSTARRS on March 22 photographed with a 200mm lens at dusk on a motorized tracking platform. Credit: Bob King

Last night under the clearest of skies I easily found Comet C/2011 L4 PANSTARRS in the constellation Andromeda about 15 degrees above the horizon an hour after sunset. Twilight was still a factor as was the rising full moon. That’s probably why the comet remained at the very limit of naked eye vision. Binoculars – I use 10x50s – clearly showed the comet’s bright parabolic head and two degrees (four full diameters) of tail streaming up and to the right.

Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet.  The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium
Comet PANSTARRS shown every three days as it moves across Andromeda, passing near the Andromeda Galaxy around April 3. You can use Cassiopeia to point you to Beta Andromedae and from there to the comet. The map shows the sky facing northwest about one hour after sunset. Comet and galaxy brightness are exaggerated for the sake of illustration. Stellarium

The comet has faded considerably since it first emerged into the evening twilight three weeks ago. Its head now shines around magnitude 3.5 and is noticeably fainter than the stars of the Big Dipper. As compensation, PANSTARRS is now easier to find, since it’s both higher up in the sky and near a string of moderately bright stars in the constellation Andromeda.

PANSTARRS treks northward through Andromeda en route to the W of Cassiopeia in the next two weeks. It won’t be long before the comet becomes circumpolar and remains visible all night long. The term refers to celestial objects that circle around the pole star without setting. The Big Dipper is the most familiar circumpolar constellation for much of the U.S. and Canada.

Comet PANSTARRS in the early dawn sky during the first part of April. The map shows the sky facing northeast about 75 minutes before sunrise. Stellarium
Comet PANSTARRS in the early dawn sky during the first part of April. Once again, you can use Cassiopeia to help get you there. Don’t forget binoculars! They’re now essential to seeing the comet. The map shows the sky facing northeast about 75 minutes before sunrise. Stellarium

On its journey to all-night visibility, PANSTARRS started pulling a double-shift this week. You can now see it both at dusk and at dawn. Although a bright moon will compromise the dawn view for a few days, you can watch for the comet low in the northeastern sky starting about hour and 15 minutes before sunrise. For the moment, it’s about the same altitude above the horizon during both morning and evening hours. Evening is still preferred only because the bright moon has finally departed the sky during the hour or so the comet is visible.

Comet C/2011 L4 PANSTARRS sports a broad dust tail and a narrower red-tinted tail in this photo made on March 15, 2013. The red tail may be from sodium atoms released by materials colliding with each other as they leave the comet under pressure and heat from the sun. Credit: José J. Chambó
Jose Chambo’s photo of Comet C/2011 L4 PANSTARRS from Spain on March 15 reveals a broad dust tail and narrower red-tinted tail. The red tail may be from sodium atoms released by materials colliding with each other as they jet off the comet’s nucleus. Click image to see more photos. Credit: José J. Chambó

Through my 15-inch telescope last night,  PANSTARRS’ head held a brilliant topaz gem – the false nucleus. This tiny ball of bright, fuzzy light contains the icy comet itself,  hidden behind a fury of its own dust and vapor boiled off by the sun’s heat.

Here’s some additional images and videos of PANSTARRS that Universe Today has received from readers:

Zlatan Merakov created this timelapse from images he took on March 20 from Smolyan, Bulgaria.

The view of Comet PANSTARRS  L4  on 03-22-2013 over Warrenton, Virginia.  Modified Canon Rebel Xsi DSLR 30 second exposure, ISO 1600, University Optics 80mm  F6 Refractor (600mm). Credit and copyright: John Chumack.
The view of Comet PANSTARRS L4 on 03-22-2013 over Warrenton, Virginia.
Modified Canon Rebel Xsi DSLR
30 second exposure, ISO 1600, University Optics 80mm F6 Refractor (600mm). Credit and copyright: John Chumack.
Comet C/2011 Pan-STARRS over Gradara Castle in Italy. Credit and copyright: Niki Giada.
Comet C/2011 Pan-STARRS over Gradara Castle in Italy. Credit and copyright: Niki Giada.