Comet Section

ALPO COMET SECTION NEWS FOR DECEMBER 2014

2014-December-9

Latest News

The comet event of October was the incredible close flyby of Mars by long-period comet C/2013 A1 (Siding Spring). Though the comet was a visual letdown (it experienced a rapid fade from 10th to 12th magnitude in the weeks prior to the flyby), CCD imagers made a number of beautiful images contrasting the faint blue-green comet with brilliant red Mars. At least 7 spacecraft near or on Mars observed the comet. Though we are still awaiting the most of the results, images from the HiRise imager on the Mars Reconnaissance Orbiter found the comet’s nucleus to be smaller than expected at ~0.5 km across.

The first comet imaged from the surface of another world. C/2013 A1 (Siding Spring) from the Mars Exploration Rover (MER) Opportunity. Credit: NASA/JPL-Caltech/Cornell Univ./ASU/TAMU

November brings another comet spacecraft related first as the European Rosetta spacecraft deploys the Philae lander onto the surface of short-period comet 67P/Churyumov-Gerasimenko (scheduled for Tuesday, November 12).

Comet Section members (Salvador Aguirre, Carl Hergenrother, Gary T. Nowak, Willian Souza) have contributed visual and CCD magnitude estimates during October for comets C/2012 K1 (PANSTARRS), C/2012 X1 (LINEAR), C/2013 A1 (Siding Spring), C/2013 US10 (PANSTARRS), C/2014 E2 (Jacques), C/2014 Q1 (PANSTARRS), C/2014 Q2 (Lovejoy), C/2014 Q3 (Borisov) and C/2014 R1 (Borisov). CCD images for comets 17P/Holmes, 32P/Comas Sola, 108P/Ciffreo, 110P/Hartley 3, 201P/LONEOS, C/2011 J2 (LINEAR), C/2013 A1 (Siding Spring), C/2013 V4 (Catalina), C/2014 E2 (Jacques), C/2014 Q3 (Borisov) and C/2014 R1 (Borisov) were submitted by Denis Buczynski, Manos Kardasis and Gianluca Masi. Some of the more interesting observations were made of the outbursting Halley-family comet C/2014 Q3 (Borisov) and split comet C/2011 J2 (LINEAR).

Evening Comets

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

As November begins, C/2012 K1 (PANSTARRS) is the only comet bright enough to be easily seen in small telescopes or binoculars. But this is only true for southern hemisphere or low northern latitude observers. For the majority of us at northern mid-latitudes, the comet will be too far south this month. The comet comes back north in late December but it may be too faint for most backyard observers by then. CCD observers should be able to follow it for many months into the future. This month K1 moves through the constellations of Pictor (Oct 1-5), Dorado (6-10), Reticulum (10-19), Eridanus (19-23) and Phoenix (23-31).

Since the comet reappeared in early September after solar conjunction, 29 visual magnitude estimates have been submitted to the Section from Willian Souza (24!), Salvador Aguirre (2), Carl Hergenrother (2) and Gary T. Nowak (1). The comet has held steady around magnitude 7.5, give or take a few tenths of a magnitude, over the past few months. This month should see the comet starts to fade into obscurity as it moves away from the Sun (1.49 to 1.83 AU) and Earth (0.95 to 1.46 AU).

Lightcurve of comet C/2012 K1 (PANSTARRS) from visual magnitude estimates submitted to the ALPO Comet Section by Salvador Aguirre, Carl Hergenrother, Gary T. Nowak, John Sabia and Willian Souza.

Recent ALPO images and observations of C/2012 K1 (PANSTARRS) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

Morning Comets

C/2014 Q2 (Lovejoy) [Perihelion on 2015-Jan-30 at 1.29 AU from the Sun]

A year ago, comet C/2013 R1 (Lovejoy) was a nice bright winter comet. This year Terry Lovejoy of Australia may have done it again. His latest comet, C/2014 Q2 (Lovejoy) is rapidly brightening and should be a small telescope/binocular object by the end of November. Since its discovery on August 17 it has increased in brightness from 14th to 10th magnitude. This is a rapid rate of brightening. Whether it continues is still to be seen but it suggests that the new Lovejoy may be a nice 7th to 8th magnitude comet in January/February as it passes within 1.29 AU of the Sun (on January 30) and 0.47 AU of Earth (January 7/8).

Similar to PANSTARRS this month, Comet Lovejoy is a far southern object this month and northern observers will have to wait till late December for a clear view. As the comet approaches the Sun (1.84 to 1.57 AU) and Earth (1.67 to 1.05 AU), it moves slowly near the border of Vela and Puppis. Two visual observations by Salvador Aguirre and 2 CCD observations by Carl Hergenrother have been received by the Section for C/2014 Q2.

Recent ALPO images and observations of C/2014 Q2 (Lovejoy) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

New Discoveries

Only two comets were discovered since the last Comet Section News update. Both comets were found by Richard Kowalski of the Catalina Sky Survey. P/2014 U2 (Kowalski) was first spotted on October 18 at 18th magnitude. At discovery, the comet was just past perihelion (1.17 AU) and perigee (0.38 AU). The fact that it was still only 18th magnitude when so close to the Sun and Earth makes this Comet Kowalski a very faint comet intrinsically. It returns to perihelion in 2019. The other new Comet Kowalski is C/2014 U3, a long-period comet discovered on October 26 at 19th magnitude. With perihelion on October 10, 2014 at 2.58 AU from the Sun, this comet will not get any brighter.

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET SECTION NEWS FOR OCTOBER 2014

2014-October-4

Evening Comets

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

Comet Jacques is the brightest comet of 2014 having peaked at V ~ 6 in early/mid-July (not counting small SOHO comets very close to the Sun). Now 3 months past perihelion, Jacques has rapidly faded and is currently near 10th magnitude in Aquila (where it will spend the month). It will fade even further as it moves from 1.79 AU to 2.22 AU from the Sun and 1.30 AU to 2.29 AU from Earth.

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery andMagnitude Database. Finder charts can be found on the Comet Chasing website.

C/2013 V5 (Oukaimeden) [Perihelion on 2014-Sep-28 at 0.63 AU from the Sun]

Comet Oukaimeden is still with us. Due to its intrinsic faintness, there were concerns that it would disintegrate as it approached its late September perihelion. While disintegration may still happen, as of early October the comet was looking healthy. Willian Souza and Carl Hergenrother submitted 14 visual and CCD magnitude estimates during September. Before being lost in the glare of twilight at mid-month, the comet had brightened to V~6.5.

Now past perihelion the comet is rapidly fainting as it moves away from the Sun (0.63 to 0.94 AU) and Earth (0.83 to 1.83 AU). This month Oukaimeden will be a difficult observation for northern observers and just a little better for southern observers as the comet does not stray far from the Sun. It starts the month in Hydra (Oct 1-3) before moving into Libra (Oct 3-31).

Recent ALPO images and observations of C/2013 V5 (Oukaimeden) can be found in the Comet Section Image Galleryand Magnitude Database. Finder charts can be found on the Comet Chasing website.

C/2013 A1 (Siding Spring) [Perihelion on 2014-Oct-25 at 1.40 AU from the Sun]

Siding Spring will pass within ~132,000 km of Mars (just 1/3rd the Earth-Moon distance) on October 19. For Martians and spacecraft near Mars, the comet will be a brilliant object of negative magnitude. Here on Earth, the comet is an evening object moving from Scorpius (Oct 1-11) to Ophiuchus (Oct 11-31). Unfortunately the comet has been fading intrinsically and recent reports put it much fainter than predicted at 10-11th magnitude. Regardless of what’s really up with Siding Spring, it will probably remain fainter than 10th magnitude this month.

Recent ALPO images and observations of C/2013 A1 (Siding Spring) can be found in the Comet Section Image Gallery andMagnitude Database. Finder charts can be found on the Comet Chasing website.

Morning Comets

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

Finally a comet that isn’t underproducing this month! C/2012 K1 is a morning object moving from through Hydra (Oct 1-3) and Puppis (Oct 3-31) this month. By the end of the month, it will be a difficult object for far northern observers.

Observations by Willian Souza this month saw K1 holding fairly steady between 7th and 8th magnitude. We should expect more of the same this month as an increasing heliocentric distance (1.20 to 1.49 AU) is balanced by a decreasing geocentric distance (1.35 to 0.95 AU).

Recent ALPO images and observations of C/2012 K1 (PANSTARRS) can be found in the Comet Section Image Galleryand Magnitude Database. Finder charts can be found on the Comet Chasing website.

New Discoveries

Since the last Comet Section News post, 10 new comets were discovered: C/2014 Q6 (PANSTARRS), C/2014 QU2 (PANSTARRS), C/2014 R1 (Borisov), C/2014 R3 (PANSTARRS), C/2014 R4 (Gibbs), P/2014 R5 (Lemmon-PANSTARRS), C/2014 S1 (PANSTARRS), C/2014 S2 (PANSTARRS), C/2014 S3 (PANSTARRS) and P/2014 S4 (Gibbs). Nearly all of these comets are expected to remain faint. C/2014 R1 (Borisov) was discovered by Galin Borisov with a telescope in Russia at ~16th magnitude on Sept 5, 2014. Initially expected to be a faint comet, it has recently been observed as bright as 12th magnitude leading to hopes that it will become brighter when it reaches perihelion on Nov 20 at 1.33 AU. The comet is on a relatively short-period orbit with a period of ~193 years.

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET SECTION NEWS FOR SEPTEMBER 2014

2014-September-28

Section Updates

As September begins Comet C/2014 E2 (Jacques) should be a bright 7th magnitude in the evening sky. Jacques will fade rapidly as it moves away from the Sun and Earth. The morning sky is the home of two additional bright comets. C/2012 K1 (LINEAR) will once again become visible around ~7th magnitude and C/2013 V5 (Oukaimeden) may brighten from ~8th to 5th magnitude. Oukaimeden is an intrinsically faint comet making its first passage through the inner Solar System. Such comets have a history of rapid fading or even disintegration. Close monitoring is requested.

August was a very active month for the Comet Section. A number of observations were submitted for bright comets C/2014 E2 (Jacques) and C/2013 V5 (Oukaimeden) as well as fainter comets such as C/2011 J2 (LINEAR), C/2013 A1 (Siding Spring), C/2013 UQ4 (Catalina), C/2014 M3 (Catalina), C/2014 Q3 (Borisov), 108P/Ciffreo and 110P/Hartley 3. Visual magnitude observations were submitted by Carl Hergenrother (12), Willian Souza (8), John Sabia (2) and Salvador Aguirre (1). CCD images and drawing were submitted by Denis Bucyznski, Jean-Francois Coliac, Carl Hergenrother, Manos Kardasis, Gianluca Masi, Frank Melillo, and John Sabia. Thanks to everyone who contributed observations in August.

Thanks to the efforts of Gary Kronk, much of the Comet Section archive (post-1980) has been digitized. The images and drawings have been uploaded to the Section Gallery. I would also like to mention John Sabia for sending in many of his older comet images and Gary Nowak for contributing his recent magnitude estimates. Currently the Image Gallery includes ~800 images of 125 different comets going back to 1965’s Ikeya-Seki. Unfortunately, much of the material submitted to the section prior to 1980 is MIA. If you have observations of any comets, and specifically those before 1980, that are not in the Comet Image Gallery, please consider submitting them (perhaps again) to the Section.

Evening Comets

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

Comet Jacques is the brightest comet of 2014 having peaked at V ~ 6 in early/mid-July (not counting small SOHO comets very close to the Sun). Now almost 2 months past perihelion, Jacques has been intrinsically fading at a fast rate during August. Though moving away from the Sun, the comet rapidly approached Earth and passes within 0.56 AU of us on Aug 28/29. The decreasing range to the comet helped offset the comet’s intrinsic fading and as a result it is still around V ~ 7 at the end of August.

On September 1, Jacques is located 1.35 AU from the Sun and 0.58 AU from Earth. By the end of the month it will be 1.79 AU from the Sun and 1.30 AU from Earth. The comet is well placed in the evening sky for northern observers and will be visible to most southern observers by mid-month. The comet starts September is Cepheus (Sept 1) and then moves through Cygnus (Sept 2-14), Vulpecula (14-21), Sagitta (21-24) and Aquila (24-31). The comet is expected to fade from magnitude 7 to 10.

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

Frank's image of Comet Jacques does a great job of showing how the comet looks in small binoculars (fairly round, well condensed, ~10' coma).

C/2013 A1 (Siding Spring) [Perihelion on 2014-Oct-25 at 1.40 AU from the Sun]

Siding Spring will pass within ~132,000 km of Mars (just 1/3rd the Earth-Moon distance) on October 19. For Martians and spacecraft near Mars, the comet will be a brilliant object of negative magnitude. Here on Earth, the comet is a southern object for much of the month. It moves from Tucana (Sept 1) to Octans (Sept 1-4), Pavo (4-17), Telescopium (17-21), Ara (21-25) and Scorpius (25-31). The comet should be in the 9th-10th magnitude range all month.

Recent ALPO images and observations of C/2013 A1 (Siding Spring) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

Morning Comets

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

Comet PANSTARRS passes perihelion on August 27 though it will be located on the other side of the Sun. A difficult morning object at the start of the month, the comet gets progressively easier to observer over the coming weeks as it moves through Cancer (Sept 1) and Hydra (Sept 1-31). On Sept 1, it will be 1.06 AU from the Sun and 1.90 AU from Earth and perhaps as bright as 7th magnitude. By the end of the month it will be 1.20 AU from the Sun and 1.35 AU from Earth. The decreasing distance from Earth should produce a slow brightening of the comet.

Recent ALPO images and observations of C/2012 K1 (PANSTARRS) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

C/2013 V5 (Oukaimeden) [Perihelion on 2014-Sep-28 at 0.63 AU from the Sun]

Comet Oukaimeden may the object to watch this month. Already magnitude 7.5-8.0 at the start of the month, it could brighten to 5th magnitude. The comet is dynamically new (making its first passage through the inner Solar System) and intrinsically faint. It is possible the comet may disintegrate similar to what we saw last year with ISON. In fact, the comet’s appearance on CCD images is reminiscent of ISON at the same heliocentric distance. All types of observations are requested.

Southern Hemisphere observers will be able to follow Oukaimeden through perihelion. Northern observers will loss the comet after the first week or two of September. The comet’s heliocentric distance decreases from 0.85 AU on the 1st to 0.63 AU at perihelion on the 28th. Its heliocentric distance drops from 0.85 AU to 0.48 AU at mid-month and back to 0.83 AU at the end of the month.

Recent ALPO images and observations of C/2013 V5 (Oukaimeden) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

New Discoveries

Two new discoveries promise to be bright enough for small telescopes in the future. C/2014 Q1 (PANSTARRS) could be a brilliant object next summer though Earth-bound observers will miss out on the best of this comet as it will be close to the Sun for months around perihelion. C/2014 Q2 (Lovejoy) may make a nice binocular comet this December/January.

Comet Name              Disc Date   Mag     Perihelion     Estimated   Comments
                                           Date      Dist  Max Bright
C/2014 Q3 (Borisov)     2014-08-22   16  2014-11-18  1.64      15      stays faint
C/2014 Q2 (Lovejoy)     2014-08-17   14  2015-01-30  1.30       7 !    0.48 AU from Earth in early Jan
C/2014 Q1 (PANSTARRS)   2014-08-16   18  2015-07-05  0.32       2 !!   close to the Sun for months around perihelion
P/2014 O3 (PANSTARRS)   2014-07-30   20  2014-04-17  4.64      20      ~20.7 y period
C/2014 OE4 (PANSTARRS)  2014-07-26   20  2016-10-16  6.24      17      stays faint

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET HIGHLIGHTS FOR AUGUST 2014

2014-August-1

Section Updates

The observing highlight of August should be 6th magnitude comet C/2014 E2 (Jacques). It is one of a number of comets visible with small telescopes and binoculars in the morning sky this month. But the comet highlight of August will be provided by the spacecraft Rosetta as it rendezvous with comet 67P/Churyumov-Gerasimenko.

The Comet Section received 7 magnitude estimates in July of comets C/2014 E2 (Jacques), C/2013 UQ4 (Catalina), C/2013 A1 (Siding Spring), C/2012 X1 (LINEAR) and C/2012 K1 (PANSTARRS). A number of CCD images, including an excellent sequence of C/2013 UQ4 (Catalina) over many nights, was submitted by Gianluca Masi of Italy. Though C/2013 UQ4 only brightened up to 9th magnitude, it displayed a number of jets and tails as it flew within 0.32 AU of Earth in early July.

Gary Kronk has been hard at work digitizing the Comet Section archives. As a result, the Section’s Image Gallery now contains over 600 images and drawings of 110 different comets going back to Ikeya-Seki in 1965. John Sabia has also contributed a number of older images of his that were not in the archive. If you have old (or new) comet images that are not in the Gallery, please consider submitting them.

Evening Comets

C/2012 X1 (LINEAR) [Perihelion on 2014-Feb-21 at 1.60 AU from the Sun]

This comet has been followed by visual observers for ~10 months now. Long past its February perihelion, X1 is currently around 10th magnitude and poorly placed for northern observers as it drifts southward from a declination of -44° in Grus to -50° in Indus. It starts August at around magnitude 10.0-10.5 (2.60 AU from the Sun, 1.70 AU from Earth). By the end of the month it should be around magnitude 11.0 (2.90 AU from the Sun, 2.08 AU from Earth).

Finder charts for C/2012 X1 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

Morning Comets

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

2014’s brightest comet (so far) is C/2014 E2 (Jacques). Discovered by Brazilian astronomer Cristóvão Jacques with the Southern Observatory for Near Earth Asteroid Research (SONEAR) 0.45-m telescope on 2014 March 13, the comet was well followed by Section contributors during March, April and May. After spending June and the first half of July close to the Sun, Jacques once again is visible as a 6th-7th magnitude comet in the morning sky. During July, Jacques’ distance from the Sun increases from 0.90 to 1.35 AU. Fortunately its distance from Earth decreases from 1.05 to 0.56 AU on August 28/29. As a result, Jacques should remain between 6th and 7th magnitude all month long as it moves through Auriga, Perseus, Camelopardalis, Cassiopeia and Cepheus. The following plot contains visual magnitude estimates submitted to the Section by Salvador Aguirre and Carl Hergenrother.

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery and Magnitude Database. Finder charts can be found on the Comet Chasing website.

C/2013 A1 (Siding Spring) [Perihelion on 2014-Oct-25 at 1.40 AU from the Sun]

We are definitely on the wrong planet for this comet! Siding Spring will pass within ~132,000 km of Mars (just 1/3rd the Earth-Moon distance) on October 19. For Martians (including the armada of spacecraft at Mars), the comet will be a brilliant object of negative magnitude. If the nucleus is larger than a few 100 meters, it should be resolvable by the Mars Reconnaissance Orbiter’s HIRISE camera. Here on Earth, the comet starts August around magnitude 10.2 (1.85 AU from the Sun, 1.46 AU from Earth) and should brighten to magnitude 8.5 to 9.0 by Sep 1 (1.60 AU from the Sun, 0.90 AU from Earth). Unfortunately for northern observers (but good for southern observers), the comet starts the month far south (-39° declination) and only heads deeper south as it traverses the constellations of Eridanus, Horologium, Hydrus, and Tucana. Northern observers get a chance to observe it in mid-October as it nears its date with Mars.

Recent ALPO images and observations of C/2013 A1 (Siding Spring) can be found in the Comet Section Image Gallery and MagnitudeDatabase. Finder charts can be found on the Comet Chasing website.

C/2013 V5 (Oukaimeden) [Perihelion on 2014-Sep-28 at 0.63 AU from the Sun]

Michel Ory of Switzerland discovered this comet with an Oukaimeden Observatory telescope near Marrakesh, Morocco. Currently around magnitude 10.5 (1.31 AU from the Sun, 1.92 Au fromEarth), this comet may rapidly brighten as it gets closer to both the Sun and Earth. By the end of August, the comet may be a 7th magnitude object (0.85 AU from the Sun, 0.85 AU from Earth). It will be interesting to watch the development of this comet. Its orbit suggests it is a new comet on its first passage through the inner Solar System. Such new and relatively faint comets can be prone to disintegrating. We’ll have to watch and see. This month it is a morning object moving against the stars of Orion and Monoceros.

Recent ALPO images and observations of C/2013 V5 (Oukaimeden) can be found in the Comet Section Image Gallery and MagnitudeDatabase. Finder charts can be found on the Comet Chasing website.

Other Comets of Interest

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

Comet PANSTARRS was well observed by Section contributors from early March to early July as it brightened from magnitude 11.5 to 7.9. Since early July it has been too close to the Sun to observe. This will remain the case till September when it will become visible in the morning sky as a 7th-8th magnitude object. Luckily the comet is now visible in the SOHO C3 field of view through mid-month (though at 7th magnitude or so it is a faint object for SOHO).

67P/Churyumov-Gerasimenko [Perihelion on 2015-Aug-13 at 1.24 AU from the Sun]

The big comet news of the month is the arrival of the European Rosetta spacecraft at short-period comet 67P/Churyumov-Gerasimenko. Rosetta will be the first spacecraft to orbit a comet’s nucleus. The previous missions were quick flybys. Already Rosetta has returned images of the nucleus showing a dual “contact binary” structure. The images and results from Rosetta will only get better as the spacecraft gets closer to the comet and the comet gets closer to the Sun. The comet is currently ~20th magnitude in Sagittarius and will brighten to ~11th magnitude by the summer of 2015.

Crop from the 1 August processed image of comet 67P/Churyumov-Gerasimenko, to focus on the comet nucleus. Credits: ESA/Rosetta/NAVCAM

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET HIGHLIGHTS FOR JULY 2014

2014-July-1

Section Updates

During June the Comet Section received images from Frank Melillo and Carl Hergenrother of comets C/2012 K1 (PANSTARRS) and C/2013 UQ4 (Catalina). Numerous positive visual and CCD magnitude estimates by Salvador Aguirre (2), John Sabia (3) and Carl Hergenrother (6) have been submitted for comets C/2012 K1 (PANSTARRS), C/2012 X1 (LINEAR) and C/2013 UQ4 (Catalina).

Evening Comets

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

Comet PANSTARRS will spend most of July too close to the Sun to be observed. Observations during the first week of July are still possible in the evening sky though the Moon will interfere. Once the comet is lost in the glare of the Sun, it will be invisible to ground-based observers till September though SOHO will be able to image the comet in early August. So far we have received 29 visual magnitude estimates of this comet from 3 observers. Observations over the past month suggest that K1’s rate of brightening has slowed with recent observations placing the comet around 8th magnitude. We’ll have to wait and see what how bright this comet will be when we see it again in September.

Timing is everything with comets. This time around, PANSTARRS reaches perihelion when it and the Earth are on opposite sides of the Sun. If PANSTARRS had reached perihelion near February 21, it would be located only 0.11 AU from Earth and might be a brilliant 1st to 2nd magnitude comet near opposition. Over the course of a week or so it would have raced from Virgo westward into Eridanus.

Recent ALPO images and observations of C/2012 K1 (PANSTARRS) can be found in the Comet Section Image Gallery and Magnitude Repository. Finder charts for C/2012 K1 can be found on the Comet Chasing website.

Morning Comets

C/2012 X1 (LINEAR) [Perihelion on 2014-Feb-21 at 1.60 AU from the Sun]

Visual observers have followed this comet for over 9 months. It literally “burst” onto the scene in late October when it experienced a large outburst and brightened to 7th magnitude. A few weeks after the outburst the comet settled back down and has been well behaved since then. It spent much of February/March/April/May between magnitude 8.0 and 8.5. Over the past month or so X1 has been in a rapid fade and is now near magnitude 10.0. The comet should rapidly fade from the reach of visual observers this month. Though it is approaching opposition, it is also moving south starting the month at a declination of -31° in Piscis Austrinus and ending the month in Grus at -44°. The Section has received 30 visual magnitude estimates for this comet.

Finder charts for C/2012 X1 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

C/2013 UQ4 (Catalina) [Perihelion on 2014-Jul-05 at 1.08 AU from the Sun]

This odd-ball of a comet is making a close approach to within 0.32 AU of Earth on July 10. I say odd-ball because for months after discovery it appeared as an inactive asteroid. Though it has not brightened as much as hoped (still around 10th magnitude as of 7/1), it has become a very photogenic comet with strong dust jets and a large gas coma. The comet starts the month at a distance of 1.08 AU from the Sun and 0.48 AU from Earth in Pegasus. It moves quickly through Andromeda, Lacerta, Cepheus, and Draco before ending the month in Bootes at a 1.16 AU from the Sun and 0.84 AU from Earth. It should reach its peak brightness at magnitude ~9 around the time of close approach to Earth.

Finder charts for C/2013 UQ4 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

C/2013 UQ4 (Catalina) in a co-added 15x60 sec exposure with the Vatican 1.8-m telescope.

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

Jacques reaches perihelion on July 2nd at a distance of 0.67 AU from the Sun. Unfortunately, as was the case with C/2012 K1, it is too close to the Sun and on the far side of the Sun at that time. During June our only view of the comet was with the coronagraphic imager on the SOHO spacecraft (you’ll find some of these images in the ALPO Comet Section Image Gallery). The comet was not very impressive in the SOHO images and it is very possible that it is running fainter than hoped. We’ll catch another glimpse of the comet during the second half of July as it emerges from the glow of dawn moving north from Taurus into Auriga. The comet may be as bright as magnitude 6 or 7 at that time.

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery and Magnitude Repository. Finder charts can be found on the Comet Chasing website.

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET HIGHLIGHTS FOR JUNE 2014

2014-May-31

Section Updates

Comet lightcurve plots have been added to the Comet Magnitude Repository page. The Comet Section main page has two new features: the latest comet images and a table of bright comets (containing current brightness, constellation, elongation from the Sun, distances from Sun and Earth in AU, time and distance of perihelion, and time and distance for closest approach to Earth.

Over the past month, we have received a number of great images from Frank Melillo, John Sabia and Carl Hergenrother of comets C/2012 K1 (PANSTARRS) and 209P/LINEAR. Numerous positive visual and CCD magnitude estimates by Salvador Aguirre (9), John Sabia (2) and Carl Hergenrother (10) have been submitted for comets C/2012 K1 (PANSTARRS), C/2012 X1 (LINEAR), C/2014 E2 (Jacques) and 209P/LINEAR.

Evening Comets

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

As May comes to a close, Comet Jacques holds the spot as brightest comet at magnitude ~7.5. Unfortunately, the comet is also racing towards the Sun and is no longer visible to Northern observers. Even Southern observers will loss the comet to the bright evening twilight after the first few nights of June. Luckily Jacques will become visible in the FOV of the SOHO C3 imager during the last 10 days of May. At that time, the comet may be as bright as 5th magnitude. You can follow Comet Jacques in the C3 images here.

A dynamically old comet, Jacques has the potential to remain bright and active through perihelion. Starting in mid-July the comet will again be visible to observers (though not those in the Southern Hemisphere). It may still be a nice 5th magnitude comet at that time as it will be only a few weeks past its July 2nd perihelion (0.67 AU) and rapidly approaching Earth for a late August close approach (0.56 AU).

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery and Magnitude Repository. Finder charts can be found on the Comet Chasing website.

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

PANSTARRS is currently around 8th magnitude. With Jacques leaving the night sky for awhile, C/2012 K1 should be the brightest, observable, comet of the month. Except for a slow but steady brightening, the comet hasn’t changed much over the past few months. More of the same should be expected for June. The comet continues to sport two tails, a broad, bright dust tail trailing the comet’s orbit and a narrow, fainter ion tail (see the images in the Comet Section Gallery).

PANSTARRS starts the month in Ursa Major and will travel across Leo Minor before ending the month in Leo. By that time, the comet will be very low in the western sky at dusk. It will be lost to observers from July through mid-September when it may be as bright as 6th magnitude. A dynamically new comet it is very possible to be fainter than predicted near and after perihelion. C/2012 K1’s distance from the Sun will decrease from 1.74 to 1.41 AU and its distance from Earth will increase from 1.65 to 1.99 AU.

Morning Comets

C/2012 X1 (LINEAR) [Perihelion on 2014-Feb-21 at 1.60 AU from the Sun]

Now over three month since perihelion, C/2012 X1 is still around magnitude 8.5-9.0. The comet’s brightness will fade slowly as it moves from Aquarius into Piscis Austrinus. Its distance from the Sun will increase from 2.07 to 2.32 AU this month while its distance from Earth slightly decreases from 1.61 to 1.55 AU.

Finder charts for C/2013 R1 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

C/2013 UQ4 (Catalina) [Perihelion on 2014-Jul-05 at 1.08 AU from the Sun]

This comet appeared to be inactive, and hence was considered an asteroid, when discovered back on October 23, 2013 by the Catalina Sky Survey. It wasn’t until April 26 that a growing number of observers started to note a coma and tail. Hence, what was once asteroid 2013 UQ4 is now Comet Catalina. The question now is how bright it will get. As the month starts, the comet is only visible from the Southern Hemisphere at around 12-13th magnitude. By the middle of the month, the comet will be visible to northern observers. As the month progresses the comet will move closer to the Sun (from 1.22 to 1.08 AU) and rapidly closer to Earth (from 1.46 to 0.48 AU) on its way to perihelion on July 5 (at 1.08 AU) and closest approach to Earth on July 10 (at 0.32 AU). It is a morning object moving northward from Pisces into Pegasus.

Back in 2002, comet C/2001 OG108 (LONEOS) put on a similar display. I remember being able to observe the comet as an inactive 16th magnitude asteroid one month, a bright 8th magnitude binocular comet (with strong active jets in large telescopes) a few months later and then again as an inactive asteroid (surrounded by residual dust) a month or so after that.

We are still waiting for our first Comet Section magnitude estimates for this interesting object.

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET HIGHLIGHTS FOR May 2014

2014-May-03

Section Updates

A Comet Magnitude Repository page has been added to the Comest Section site. This page will list all visual and CCD magnitude estimates submitted to the Section. Currently, we have magnitude estimates for all the comet mentioned below. Links to instructions and other resources related to making comet magnitude estimates can be found here.

Evening Comets

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

A relatively new discovery, C/2014 E2 (Jacques) rapidly brightened and is set to take the title of ‘brightest comet in the sky’. Magnitude estimates have been all over the place and range from 8th to 10th magnitude. The cause of the problem is that the comet appears to possess a very large, low surface brightness gas coma. As a result, brightness measurements are very sensitive to sky conditions, magnification and even the observer’s sensitivity to blue light. Based on CCD measurements and those of visual observers observing under excellent sky conditions, the comet seems to currently be between magnitude 8.0 and 8.5. If it continues brightening it could be close to 6-7th magnitude by the end of the month. Unfortunately by then, the comet will be too close to the Sun for observers in the Northern Hemisphere. Southern Hemisphere observers will be able to follow the comet into early June before they also lose it in the glare of the Sun. The comet will be back for northern observers in mid-July when it may be as bright as 5th magnitude. Southern observers are out of luck till September.

This month the comet is moving towards the northwest in Monoceros. On May 1st it is 1.38 AU from the Sun and 1.19 AU from Earth. By the end of the month its heliocentric distance decreases to 0.92 AU while its geocentric distance increases to 1.61 AU. Comet Jacques is a dynamically old comet meaning it has been through the inner Solar System before. Such comets usually brighten at a faster than average rate so Jacques is definitely one to keep an eye on.

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery. Finder charts can be found on the Comet Chasing website.

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

PANSTARRS is currently around 9th magnitude. It should continue to slowly brighten as it moves through Ursa Major. The comet continues to sport two tails, a broad, bright dust tail trailing the comet’s orbit and a narrow, fainter ion tail. CCD imagers have also been noting some strange coma morphology such as persistent dust halo (see the images in the Comet Section Gallery for the development of this feature). The current prediction is for PANSTARRS to brighten up to 7th magnitude. One caveat though, this is another example of a dynamically new comet making its first pass through the inner Solar System (just like last year’s ISON) and these comets have a track record of underperforming when close to the Sun. Comet PANSTARRS starts the month 2.11 AU from the Sun and 1.48 AU from Earth and ends the month 1.74 AU from the Sun and 1.65 AU from Earth.

Finder charts for C/2012 K1 can be found on the Comet Chasing website.

Morning Comets

C/2012 X1 (LINEAR) [Perihelion on 2014-Feb-21 at 1.60 AU from the Sun]

Now over two month since perihelion, C/2012 X1 is still around magnitude 8.0-8.5. The comet’s brightness should fade slowly as it moves through Aquarius. Its distance from the Sun will increase from 1.84 to 2.07 AU this month while its distance from Earth slightly decreases from 1.76 to 1.61 AU.

Finder charts for C/2013 R1 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

Fainter, but Noteworthy Comets

209P/LINEAR [Perihelion on 2014-May-06 at 0.97 AU from the Sun]

The year’s closest (predicted) comet approach to Earth will be by 209P/LINEAR as it passes within 0.055 AU on May 29. The comet may produce a meteor shower on the night of May 24 UT as we encounter many of its older dust trails. Even though the comet will be very close, it is a relative runt of a comet and should only brighten up to magnitude 10-11. As of the end of April, the comet is still a faint 16th magnitude with little coma and a short tail. Still, CCD and large aperture visual observers should be able to enjoy the show as the comet rapidly moves across the sky in late May. 209P spends most of the month in Ursa Major but as it flies past Earth it rapidly moves to the south and by June 1st is located in Hydra.

Recent images can be found here.

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET HIGHLIGHTS FOR APRIL 2014

2014-April-04

Evening Comets

C/2014 E2 (Jacques) [Perihelion on 2014-Jul-02 at 0.67 AU from the Sun]

It seems like forever since there’s been a bright comet observable in the evening. C/2014 E2 (Jacques) is a new discovery by Cristovao Jacques of Belo Horizonte, Brazil. Discovered on March 13, it is the 2nd comet discovered by the Southern Observatory for Near Earth Asteroid Research (SONEAR) Observatory near Oliveira, Brazil. Since discovery the comet has rapidly brightened and recent estimates place it between magnitude 10 and 10.5 though occasionally a much brighter report has surfaced. The comet does appear to possess a rather large diffuse gaseous coma which may explain some of these discrepancies since the visibility of such comae is heavily influenced by sky conditions. Observers will be able to follow the comet into late May before it gets too close to the Sun for its 2014 July 2 perihelion at 0.67 AU from the Sun. By mid-July, the comet will be back, this time as a morning object. In late August it will approach to within 0.57 AU of Earth and may be as bright as magnitude 7-8.

The comet starts April rather far south at a declination of -30 deg in Antlia. It quickly moves to the northwest crossing Pyxis and ending the month in Monoceros. The comet should only brighten a little this month to ~9.5-10.0 (unless it really is much brighter than reported). At the start of the month, it will be located 1.82 AU from the Sun and 0.97 AU from Earth. By month’s end it will be 1.38 and 1.19 AU from the Sun and Earth, respectively.

Recent ALPO images and observations of C/2014 E2 (Jacques) can be found in the Comet Section Image Gallery. Finder charts can be found on the Comet Chasing website.

Middle of the Night Comets

C/2012 K1 (PANSTARRS) [Perihelion on 2014-Aug-27 at 1.05 AU from the Sun]

Unlike Comet Jacques, C/2012 K1 has been known for almost two years having been discovered in May of 2012. Recent reports put it between magnitude 10.0 and 10.5. It should continue to slowly brighten as it moves from Corona Borealis, through Bootes and Canes Venatici and into Ursa Major. CCD images are revealing an interesting looking comet with a large 10′ gas coma, a faint but long gas tail in the usual anti-solar direction and a short but broad dust tail trailing the comet along its orbit. CCD imagers have also been noting some strange coma morphology such as persistent dust halo (see the images in the Comet Section Gallery for the development of this feature). The current prediction is for PANSTARRS to brighten up to 7th magnitude. One caveat though, this is another example of a dynamically new comet making its first pass through the inner Solar System (just like last year’s ISON) and these comets have a track record of underperforming when close to the Sun. Comet PANSTARRS starts the month 2.46 AU from the Sun and 1.81 AU from Earth and ends the month 2.11 AU from the Sun and 1.48 AU from Earth.

Finder charts for C/2012 K1 can be found on the Comet Chasing website.

Morning Comets

C/2013 R1 (Lovejoy) [Perihelion on 2013-Dec-22 at 0.81 AU from the Sun]

Comet Lovejoy’s performance for most visual observers is coming to a close. Perhaps the most enjoyable comet of 2013, Lovejoy was a recent discovery and a surprise. Unlike the overhyped C/2011 L4 (PANSTARRS) and C/2012 S1 (ISON), Lovejoy exceeded expectations. The comet is now a faint diffuse fuzzy moving southwestward between Scutum and Serpens Cauda at magnitude 10-11. In full retreat from the Sun, the comet starts April 1.88 AU from the Sun and 1.53 AU from Earth and ends April 2.27 AU from the Sun and 1.46 AU from Earth.

Finder charts for C/2013 R1 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

C/2012 X1 (LINEAR) [Perihelion on 2014-Feb-21 at 1.60 AU from the Sun]

Now over a month past perihelion, C/2012 X1 remains the brightest comet in the sky around magnitude 8.0-8.5. The comet’s brightness should only fade a little as it moves through Aquarius. Its distance from the Sun will increase from 1.68 to 1.84 AU this month while its distance from Earth slightly decreases from 1.89 to 1.76 AU.

Finder charts for C/2013 R1 can be found on the Comet Chasing website. Its ALPO image gallery can be found here.

Fainter, but Noteworthy Comets

209P/LINEAR [Perihelion on 2014-May-06 at 0.97 AU from the Sun]

This year’s closest (predicted) comet approach to Earth will be by 209P/LINEAR as it passes within 0.06 AU in late May. The comet may also be the parent of a possible meteor shower on the night of May 24 UT as we encounter many of its older dust trails. Even though the comet will be very close, it is a relative runt of a comet and should only brighten up to magnitude 10-11. Still, CCD and large aperture visual observers should be able to enjoy the show as the comet rapidly moves across the sky in late May. This month, the comet remains near the Lynx-Camelopardalis border (near the radiant of its expected meteor shower, no coincidence here) as its distance from the Sun and Earth decrease from 1.09 to 0.97 AU and 0.49 to 0.27 AU, respectively.

Recent images can be found here.

Also, congratulations to ALPO member Rik Hill on the discovery of his 26th comet! Comet C/2014 F1 (Hill) is a faint long-period comet that probably won’t be any brighter than its current 19th magnitude.

As always, the Comet Section is happy to receive all comet observations, whether images, drawings or magnitude estimates.

- Carl Hergenrother (ALPO Comet Section Coordinator)

COMET HIGHLIGHTS for MARCH 2013

2014-Mar-2

The best comets for small telescope users remain C/2013 R1 (Lovejoy) and C/2012 X1 (LINEAR). Both of these comets have been easily visible to average backyard observer over the past 3-4 months. Though still faint at magnitude 11-12, inbound C/2012 K1 (LINEAR) is starting to show more signs of life and may break 10th magnitude during March

Outbound Comets

C/2013 R1 (Lovejoy) [T = 2013 Dec 22, q = 0.81 AU]

Comet Lovejoy was one of the best comets of 2013. Discovered only a few months prior to its late December perihelion, Lovejoy didn’t enjoy the benefit of the media hype that welcomed ‘Great Comets that Weren’t’ C/2011 L4 (PANSTARRS) and C/2012 S1 (ISON). Though not as bright as the aforementioned comets, Lovejoy was better placed for observations over a much longer span of time. Now in full retreat from the Sun, the comet has faded to magnitude 8.0-8.5. It starts the month 1.46 AU from the Sun and 1.53 AU from Earth. By the end of the month, the comet will be 1.88 AU from the Sun and 1.59 AU from Earth. The comet should continue to fade from magnitude 8.0-8.5 to close to 10.0 during the course of the month. Lovejoy is a morning object in Serpens Cauda.

Inbound Comets

C/2012 X1 (LINEAR) [T = 2014 Feb 21, q = 1.60 AU]

Comet LINEAR reached perihelion back on February 21. Discovered back in December 2012 it was never expected to become a bright comet until it underwent a major outburst last October brightening from 14th to 7th magnitude. It is now around magnitude 8.0. Since its distance from the Sun and Earth will not change much during March (heliocentric distance increasing from 1.60 to 1.68 AU while the geocentric distance decreases from 2.00 to 1.89 AU), it should not brighten or fade much. It is a morning object moving through Aquila.

Some Fainter Comets of Interest

C/2012 K1 (PANSTARRS) should become a nice binocular/small telescope comet this summer at 5th-7th magnitude. With perihelion on August 27 (q = 1.05 AU), PANSTARRS is still over 2.4 AU from the Sun this month. Similar to last year’s Comet ISON, K1 is a dynamically new comet and has showed signs of a slow-down in its brightening trend though recent visual observations suggest the comet may be brightening at a faster rate once again. The comet has also been displaying some interesting coma morphology. C/2012 K1 is shaping up to be an intriguing comet and it will be very interesting to watch the development of its brightness and morphology. The comet is a morning object located in Hercules and Corona Borealis and should brighten from around magnitude 11.5 to perhaps 10.0 this month.

Please check out the Comet Section image gallery for C/2012 K1 (PANSTARRS) and we ask that you image the comet and contribute your images and observations to the Section.

290P/Jager is a short-period comet discovered in 1998 by renowned comet imager Michael Jager. At the time of discovery the comet was on its first trip into the inner Solar System after a close-approach to Saturn (0.016 AU) decreased its perihelion distance from 8.47 to 2.13 AU. Jager passes perihelion on March 12 at 2.16 AU from the Sun (it will also be 1.65 AU from Earth at that time). Recent observations place the comet at 12-13th magnitude and we expect a similar brightness this month. It is an evening object located in Gemini.

The Section is always collecting observations (both visual and CCD) and magnitude estimates for all comets. An image gallery has been set up and now contains 309 images of 58 comets.

All ephemerides/positions for the above comets and all other comets can be generated at the Minor Planet Center and JPL/Horizons websites.

- Carl Hergenrother (Comet Section Acting Co-Coordinator)

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