Could Mercury Get A Meteor Shower From Comet Encke?

We’re sure going to miss the MESSENGER spacecraft at Mercury when it concludes its mission in 2015, because it keeps bringing us really unexpected news about the Sun’s closest planet. Here’s the latest: Mercury may get a periodic meteor shower when it passes through the debris trail of Comet Encke.

Why do scientists suspect this? It’s not from patiently watching for shooting stars. Instead, they believe the signature of calcium in Mercury’s tenuous atmosphere may be pointing to a pattern.

MESSENGER (which stands for MErcury Surface, Space ENvironment, GEochemistry, and Ranging) has been orbiting the planet for three Earth years and sees regular “surges” in calcium abundance on a predictable schedule. The researchers suspect it’s because of bits of dust colliding with Mercury and ricocheting bits of calcium up from the surface.

Mercury also picks up bits of dust from interplanetary debris, but the scientists say it’s not enough to account for the amounts of calcium they see. Extrapolating, the researchers suspect it must occur as the planet passes through debris left behind from a comet or asteroid. There are a small number of such small bodies that do this, and the scientists narrowed it down to Encke.

Illustration of MESSENGER in orbit around Mercury (NASA/JPL/APL)
Illustration of MESSENGER in orbit around Mercury (NASA/JPL/APL)

Computer simulations of the comet’s debris showed a slight difference from what researchers predicted, but they believe it’s because of variations in Mercury’s orbit as it gets tugged by larger planets, particularly Jupiter. Encke itself takes about 3.3 years to do one lap around the Sun, and has been photographed by MESSENGER in the past.

“The possible discovery of a meteor shower at Mercury is really exciting and especially important because the plasma and dust environment around Mercury is relatively unexplored,” stated lead author Rosemary Killen, a planetary scientist at NASA’s Goddard Space Flight Center in Maryland.

MESSENGER, meanwhile, is burning off the last of its fuel to stay in orbit; the final engine maneuver is expected for Jan. 21. Once that’s finished, the spacecraft will slowly spiral down towards the planet for an expected impact in March, ending the mission.

Source: NASA

Tracking Comet C/2013 R1 Lovejoy through November

Tired of comets yet? Right now, northern hemisphere observers have four (!) comets within range of binoculars in the dawn sky. Comet C/2012 S1 ISON, is, of course, expected to dazzle towards month’s end. Comet 2P/Encke is an “old standby,” with the shortest orbital period of any comet known at 3.3 years, and is making a favorable appearance this Fall. And comet C/2012 X1 LINEAR added to the morning display recently, reaching about +8th magnitude in an unexpected outburst…

But the brightest and best placed comet for morning viewing is currently Comet C/2013 R1 Lovejoy. Shining at +6th magnitude, R1 Lovejoy just passed into the constellation Leo after a photogenic pass near the Beehive Cluster (M44) in Cancer last week. We caught sight of R1 Lovejoy a few mornings ago, and it’s an easy binocular object, looking like a fuzzy unresolved globular cluster with barely the hint of a tail.

If the name sounds familiar, that’s because the comet was discovered by Australian observer Terry Lovejoy, the prolific discoverer of four comets, including the brilliant sungrazing Comet C/2011 W3 Lovejoy that survived its 140,000 kilometre perihelion passage above the surface of the Sun on December 16th and went on to dazzle southern hemisphere observers in late 2011 and early 2012.

Comet R1 Lovejoy as imaged by Rob Sparks (@HalfAstro) from Tucson, Arizona near the Beehive cluster. (Credit: Rob Sparks).
Comet R1 Lovejoy as imaged by Rob Sparks (@HalfAstro) from Tucson, Arizona passing near the Beehive cluster. (Credit: Rob Sparks).

Terry discovered R1 Lovejoy on September 7th, 2013 while it was still at magnitude +14.4. The comet is expected to top out at +4th magnitude in late November as it passes 61.4 million kilometres from Earth on November 19th and heads for perihelion at 0.877 AUs from the Sun on December 25nd, 2013. Comet R1 Lovejoy is on a 64 degree orbit highly inclined to the ecliptic, and has a period roughly 7,000 years long. The last time R1 Lovejoy graced Earthly skies, our early ancestors still thought copper smelting was a pretty hip idea!

The orbital path of Comet R1 Lovejoy through the inner solar system.
The orbital path of Comet R1 Lovejoy through the inner solar system. (Credit: NASA/JPL Solar System Dynamics explorer).

And unlike comets Encke and ISON that are plunging near the Sun, Comet R1 Lovejoy never gets closer than 19 degrees elongation from our nearest star in late December. It also reaches a maximum northern declination of 43 degrees on November 28th, the same day that ISON reaches perihelion. For mid-latitude northern hemisphere observers, R1 Lovejoy will remain well placed at 35 to 45 degrees above the northeastern horizon about an hour before sunrise through late November.

Here are some key dates to aid you in your quest to spy Comet R1 Lovejoy in late November:

November 11th: Passes near +4.5 Kappa Leonis.

November 14th: Passes from Leo into the constellation Leo Minor & passes near the +5.3 star 20 Leonis Minoris.

November 16th: Passes near the +5th magnitude stars 28, 30, and 34 Leonis Minoris.

November 18th: Passes into the constellation Ursa Major.

November 19th: Passes near the +4.8 magnitude star 55 Ursae Majoris & +5.3 magnitude star 57 Ursae Majoris.

November 19th: Closest to Earth, at 0.4 AUs distant.

The celestial path of Comet R1 Lovejoy spanning November 11th to the 30th. (Created using Starry Night Education software).
The celestial path of Comet R1 Lovejoy spanning November 11th to the 30th. (Created using Starry Night Education software).

November 21st: Passes into the constellation Canes Venatici.

November 22nd: Passes near the +6th magnitude star 4 Canum Venaticorum & the +4.2 magnitude star Chara (Beta Canum Venaticorum).

November 24th: Passes near the Sunflower Galaxy (M63).

November 27th: Passes into the constellation Boötes.

December 1st: Passes near +3.5 magnitude star Nekkar (Beta Boötis).

December 4th: crosses into Corona Borealis.

Note that passes on the list above denote passages closer than one degree of Comet R1 Lovejoy near bright objects.

Perihelion for the comet is December 25th at 0.877 AU, and its closest approach to Earth is November 19th. On this date, it will also be moving at its maximum apparent speed as seen from Earth, covering about 3 degrees of the sky every 24 hours, or the angular span of the Full Moon every 4 hours.

United Kingdom observer Pete Lawrence imaged Comet R1 Lovejoy this past weekend from his backyard garden using a 4-inch apochromatic refractor and a Canon 40D DSLR:

Comet R1 Lovejoy as imaged by Pete Lawrence on November 9th. (Credit: Pete Lawrence).
Comet R1 Lovejoy as imaged by Pete Lawrence on November 9th. (Credit: Pete Lawrence).

He also made his first confirmed binocular sighting of Comet ISON using a pair of 15×70 binocs, noting to Universe Today that “ISON’s head appears to be small and stellar compared to Lovejoy’s extended coma, which is obvious in binoculars, and also brighter!”

It’s worth noting that all four of these morning comets are on separate orbital paths, and only seem to be in the same general region of the sky as seen from our Earthly vantage point… and none of them are passing near the Earth!

This week is also a good time to hunt for comets in the pre-dawn sky for another reason: the Moon reaches Full this coming weekend on Sunday, November 17th. After this week, it will start to creep into the morning sky and interfere with deep sky observations for the next two weeks.

Comet R1 Lovejoy imaged on November 10th by astrophtographer Justin Ng. (Credit: Justin Ng).
Comet R1 Lovejoy imaged on November 10th by astrophtographer Justin Ng. (Credit: Justin Ng).

It’s also interesting to note that amateur observers discovered two more faint comets this past weekend. Though comets C/2013 V3 Nevski and C/2013 V2 Borisov aren’t slated to be anything spectacular, that brings the number of amateur discoveries to 13 for 2013. Are amateur comet hunters mounting a comeback?

In this age of automated surveys, the question is often raised as to whether amateurs can still discover comets. Keep in mind, Terry Lovejoy found Comet R1 Lovejoy with a medium-sized 8-inch Schmidt Cassegrain reflecting telescope… the age of amateur comet hunters seemes far from over in 2013!

Morning Comets Continue to Dazzle in New Images, Timelapses

While many are anticipating seeing Comet ISON, there’s more in the sky these days than just one comet. There are actually four comets now in the skies in the mornings — in addition to ISON, there’s comets 2013 R1 Lovejoy, 2P/Encke and 2012 X1 LINEAR! Unfortunately, none of these are visible to the naked eye — yet anyway.

Here are some great recent images and video of these comet taken by amateur astrophotographers. Above is Comet Lovejoy, just taken by Justin Ng from Singapore . “Comet Lovejoy will share the same part of the sky as Comet ISON this month and it presents a cool astrophotography opportunity for skywatchers and astronomers,” Justin told Universe Today via email. “This image is a result of stacking 9 images together and each image was captured using a 3 inch telescope at 5 minutes exposure time for about an hour before dawn.”

Comet 2P/Encke on October 30, 2013. The coma is partially obscuring the small barred spiral galaxy NGC 4371. Credit and copyright: Damian Peach.
Comet 2P/Encke on October 30, 2013. The coma is partially obscuring the small barred spiral galaxy NGC 4371. Credit and copyright: Damian Peach.

A gorgeous shot of Comet Encke by Damian Peach. “The fine narrow ion tail is very nicely defined which has recently developed,” Damian said via email.

Below is Damian’s image of Comet Lovejoy. “Looks as though a disconnection event may have occurred within Lovejoy’s gas tail,” Damian said. “Note the broad fan shaped condensation around half way along the tail.”

Comet 2013 R1 Lovejoy on Oct 31, 2013. Credit and copyright: Damian Peach.
Comet 2013 R1 Lovejoy on Oct 31, 2013. Credit and copyright: Damian Peach.

Here are two great timelapses of Comet ISON! The first is from Justin Ng from Singapore, taken on October 27:

Journey of Comet ISON on 27 October 2013 from Justin Ng Photo on Vimeo.

And this one is from Maik Thomas/NOVAlapse Timelapse Recordings:

Short Animation of Comet ISON – C/2012 S1 from NOVALAPSE Timelapse Recordings on Vimeo.

A recent look at ISON from Efrain Morales with black & white matched with a negative view:

Comet ISON C/2012 S1 On October 31st, 09:17-34 UTC. Coma much denser now around the nucleus and possibly both tails (Ion,Dust) on negative image (lower right) 17 x 1 minute exposures. Credit and copyright: Efrain Morales/Jaicoa Observatory
Comet ISON C/2012 S1 On October 31st, 09:17-34 UTC. Coma much denser now around the nucleus and possibly both tails (Ion, Dust) on negative image (lower right) 17 x 1 minute exposures. Credit and copyright: Efrain Morales/Jaicoa Observatory

A nice shot of Comet Lovejoy nearby in the sky to the bright binary star system Procyon in Canus Minor:

Procyon and Comet Lovejoy in the morning sky on October 31, 2013, from Arizona. Credit and copyright: Robert Sparks.
Procyon and Comet Lovejoy in the morning sky on October 31, 2013, from Arizona. Credit and copyright: Robert Sparks.

If you want to try and see these comets for yourself (good astronomy equipment needed) check out our article on how to see these four morning comets.

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Four Comets Haunt the Halloween Dawn! Here’s How to See Them

Get your astronomical trick-or-treat bags ready. An excursion under the Halloween morning sky will allow you fill it in a hurry — with comets! We’ve known for months that ISON and 2P/Encke would flick their tails in the October dawn, but no one could predict they’d be joined by Terry Lovejoy’s recent comet discovery, C/2013 R1 (Lovejoy), and the obscure C/2012 X1 (LINEAR). The last surprised all of us when it suddenly brightened by more than 200 times in a matter of days. Almost overnight, a comet found on precious few observing lists became bright enough to see in binoculars. Now comet watchers the world over are losing sleep to get a glimpse of it.

Rarely are four comets this bright in the same quadrant of sky. This map shows the sky facing east about two hours before sunrise on Oct. 31. Notice that three stars are labeled "Beta". These are (from top) Beta Cancri, Beta Leonis and Beta Coma Berenices. We'll use these three stars and the planet Mars to hone in on the comets' locations in the maps below. Stellarium
Rarely are four comets this bright in the same quadrant of sky. This map shows the sky facing east about two hours before sunrise on Oct. 31. Take note of the three stars are labeled “Beta”. These are (from top) Beta Cancri, Beta Leonis and Beta Coma Berenices. We’ll use these three stars and the planet Mars to hone in on the comets’ locations in the maps below. Stellarium

Since it’s unusual to have four relatively bright comets in the same chunk of sky at the same time, you don’t want to miss this opportunity. Now that the moon has dwindled to the slightest crescent, this is THE time to hunt for these ghostly apparitions before dawn.

etailed (updated) map showing Comet Lovejoy's progress across Cancer in the coming days. It passes very close to the Beehive Cluster on Nov. 6-7. Click for a larger version you can print and use under the stars. All dates are at 6 a.m. CDT; north is up and west to the right and stars are shown to mag. 5. All closeup charts created with Chris Marriott's SkyMap software
Detailed (updated) map showing Comet Lovejoy’s progress across Cancer in the coming days. It passes very close to the Beehive Cluster on Nov. 6-7. Click for a larger version you can print and use under the stars. All dates are at 6 a.m. CDT; north is up and west to the right and stars are shown to mag. 5. All closeup charts created with Chris Marriott’s SkyMap software

Brightest of the bunch at magnitude 8 and your best bet to see in a standard pair of 50mm binoculars is Comet Lovejoy. Using the maps, look for a round, fuzzy spot with a brighter center not far from the bright star Procyon in Canis Minor. In the coming days, Lovejoy will brighten by an additional 2 to 3 magnitudes as it trucks across Cancer headed toward the Big Dipper. This is one to watch. Lovejoy will likely reach naked eye brightness by mid-November. Small telescope users can see the comet with ease but its developing gas tail is still to faint to spot visually.

Comet Encke drops below Leo and into Virgo over the next two weeks. Your guide star Beta Leo is at upper right. Click to enlarge.
Comet Encke drops below Leo and into Virgo over the next two weeks. Your guide star Beta Leo is at upper right. Stars to mag.8. Click to enlarge.

Comet Encke treks around the sun every 3.3 years. Sometimes it’s well placed for viewing and sometimes not. Because of its short period, dedicated comet watchers meet up with it a half dozen or more times during their lives. This apparition is a favorable one with the comet well-positioned in the east at dawn near peak brightness. Current estimates place it magnitude 7.5-8 with only the wispiest of tails. Like Lovejoy, 50mm binoculars under a dark sky should nab it.

A week before Encke reaches its peak magnitude of 6 or 7 at perihelion on Nov. 21, it chases the into the glare of morning twilight. If you want to see this comet, you’ve got about 2 weeks of viewing time left. Make sure to set up in a place with an open view to the east-southeast or you’ll find it hidden by the treeline.

Animation from images taken Oct. 25-28 of comet C/2012 X1 (LINEAR) showing its rapidly expanding coma in the wake of an eruptive event in its icy crust. Click image to animate. Credit: Gianluca Masi
Animation from images taken Oct. 25 and 28 of comet C/2012 X1 (LINEAR) showing its rapidly expanding coma in the wake of an eruptive event in its icy crust. Click image to animate. Credit: Gianluca Masi

Comet C/2012 X1 would have deprived us of a unique sight had it followed the rules. Instead, an eruption of fresh, dust-laden ices from its surface blasted into space to form a gigantic glowing sphere of material that vaulted the comet’s magnitude from a wimpy 13.5 to a vol-luminous 7.5. That’s a difference of 6 magnitudes or a brightness factor of 250 times!

Outbursts of this consequence are rare; the best example of a similar blow-out happened in 2007 when Comet 17P/Holmes cut loose and brightened by half a million times from magnitude 17 to 2.8 in just under two days.

C/2012 X1 (LINEAR) hovers low in the northeast in Coma Berenices near Beta. Because it's much further from Earth than the other 3 comets it moves more slowly across the sky. Click to enlarge.
C/2012 X1 (LINEAR) hovers low in the northeast in Coma Berenices near Beta. Because it’s much further from Earth than the other three comets, it moves more slowly across the sky. It has a close conjunction with the brilliant star Arcturus in mid-November. In this map, north is at top left and west to top right. Stars to mag. 8. Click to enlarge.

As with any explosion, the cloud of debris around C/2012 X1 continues to expand. Presently measuring a healthy ~8 arc minutes in diameter (1/4 the size of the full moon), the comet will almost certainly continue to grow and fade with time. Catch it now with binoculars and small telescopes before its veil-like coma thins to invisibility. Like Encke, X1 LINEAR requires an open eastern horizon and best viewed at the start of dawn. Make it the last comet on your observing list after Lovejoy, Encke and ISON.

Mars and several other moderately bright stars in Leo will guide us to Comet ISON in the next week or two. Click to enlarge.
Mars and several other moderately bright stars in Leo will guide you to Comet ISON in the next week or two. Stars to mag. 10. Click to enlarge.

Ah, ISON. Halloween morning wouldn’t be complete without a visit to this year’s the most anticipated comet.. If it can hold itself together after a searing graze of the sun on November 28, the comet will undoubtedly become a most pleasing sight during the first three weeks of December. Right now it’s a little behind schedule on brightness, but don’t let that worry you – its best days are still ahead.

One of the finest pictures to date of Comet ISON by ace astrophotographer Damian Peach taken on Oct. 27.
One of the finest pictures to date of Comet ISON by ace astrophotographer Damian Peach taken on Oct. 27.

Of our four morning treats, Comet ISON is currently the faintest at around magnitude 9.5. Observers with binoculars in the 70-100mm range will see it under dark skies but most of us will need a 6-inch or larger scope at least until mid-November. That’s when ISON’s expected to brighten to magnitude 6, the naked eye limit. Just before it slips into the solar glare, ISON could reach 3rd magnitude around Nov. 21, normally an easy catch with the naked eye, but low altitude will hamper the view.

So open your bag wide tomorrow before dawn and keep it open the next few mornings. Trick or treat!

Weekend Comet Bonanza!

Astrophotographers were out in full force this weekend to try and capture the bonanza of comets now visible in the early morning skies! You’ll need a good-sized telescope to see these comets for yourself, however, but with the Moon now waning means darker skies and better observing conditions. Above is an absolutely gorgeous image of Comet ISON taken by Damian Peach. See below for more images of not only Comet ISON, but also Comet Encke, Comet Lovejoy and Comet LINEAR — now in outburst.

In fact, one of our “regular” contributors, John Chumack, captured all four comets in one morning, on Saturday October 26!

Four comets captured in one morning! Clockwise from top left: Comet ISON 2012 S1; Lovejoy C/2103 R1;, 2P ENCKE, Linear 2012 X1. Credit and copyright: John Chumack/Galactic Images.
Four comets captured in one morning! Clockwise from top left: Comet ISON 2012 S1; Lovejoy C/2103 R1;, 2P ENCKE, Linear 2012 X1. Credit and copyright: John Chumack/Galactic Images.

Here’s what John said about his Comet ISON image: “The tail extends off the frame it is at least 20 arc minutes long now and the coma is still around 3-4 arc minutes in diameter. The comet is looking good at about 12th magnitude and continues to slowly brighten, just 30 more days to perihelion — closest point to the Sun. Hopefully it puts on a good show for all of December too!”

And Comet Linear 2012 X1 was at 14th magnitude, but now in outburst, John said, “it is over 100-fold brighter at 8th magnitude and expanding! It was low on the horizon at dawn, and tough to get. It just cleared the trees at 7:07am in bright dawn light! I managed a couple of quick shots before my CCD was flooded completely with light!”

Of Comet Lovejoy, John said, “I found it has developed a faint long tail…it is at least 12 arc minutes in length and the comet’s coma is now around 6 arc minutes in diameter. I already notified Terry Lovejoy in Australia and he was excited to hear his comet has developed a new tail!”

Here’s a timelapse video from John of Comet Lovejoy moving through the constellation of Canus Minor:

Here’s a view from a smaller telescope from Tom Wildoner, to give a better idea of what “most of us” would see with our humbler telescopes!

The view of Mars and Comet ISON on the morning of October 28, 2013. taken using a 75mm lens, 30 seconds at ISO 800. Look for the small blur inside the yellow circle. Credit and copyright: Tom Wildoner.
The view of Mars and Comet ISON on the morning of October 28, 2013. taken using a 75mm lens, 30 seconds at ISO 800. Look for the small blur inside the yellow circle. Credit and copyright: Tom Wildoner.
Comet 2012 1X (LINEAR) on October 28, 2013 following its recent outburst. Obtained under bright twilight, low altitude and moonlight! Credit and copyright: Damian Peach.
Comet 2012 1X (LINEAR) on October 28, 2013 following its recent outburst. Obtained under bright twilight, low altitude and moonlight! Credit and copyright: Damian Peach.
Comet ISON Nucleus on October 26, 2013 at 9:43 - 10:27 U.T. Taken with QHY8 CCD & Homemade 16" Newtonian telescope. A total of 40 minutes of exposure (20 x 120 second exposures). Credit and copyright: John Chumack/Galactic Images.
Comet ISON Nucleus on October 26, 2013 at 9:43 – 10:27 U.T. Taken with QHY8 CCD & Homemade 16″ Newtonian telescope. A total of 40 minutes of exposure (20 x 120 second exposures). Credit and copyright: John Chumack/Galactic Images.

Even NASA astronomers were out trying to take images of these comets. Here’s an image taken from NASA’s Marshall Spaceflight Center:

Comet ISON on October 25, 2013, taken with a 14 inch telescope at NASA's Marshall Space Flight Center in Huntsville, Alabama. Credit: NASA/MSFC/Aaron Kingery
Comet ISON on October 25, 2013, taken with a 14 inch telescope at NASA’s Marshall Space Flight Center in Huntsville, Alabama. Credit: NASA/MSFC/Aaron Kingery

NASA explains the image:

In the early morning of Oct. 25 (6:45 a.m. EDT), NASA’s Marshall Space Flight Center in Huntsville, Ala., used a 14″ telescope to capture this image of Comet C/2012 S1 (ISON), which is brightening as it approaches the sun. The comet shines with a faint green color just to the left of center. The diagonal streak right of center was caused by the Italian SkyMed-2 satellite passing though the field of view. At magnitude 8.5, the comet is still too faint for the unaided eye or small binoculars, but it’s an easy target in a small telescope.

At this time of this image, ISON was located in the constellation of Leo the Lion, some 132 million miles from Earth and heading in toward the sun at 87,900 miles per hour.

If you want to try and see some of these comets for yourself, see our recent “explainers” of how to see Comet 2012 1X LINEAR, Comet 2P (Encke), Comet 2011 W3 (Lovejoy), and the big one, Comet ISON.

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.

How to See This Season’s “Other” Comet: 2P/Encke

2013 may well go down as “The Year of the Comet.” After over a decade punctuated by only sporadic bright comets such as 17P/Holmes, C/2011 W3 Lovejoy and C/2006 P1 McNaught, we’ve already had two naked eye comets visible this year by way of C/2012 F6 Lemmon and C/2011 L4 PanSTARRS. And of course, all eyes are on Comet C/2012 S1 ISON as it plunges towards perihelion on U.S. Thanksgiving Day, November 28th.

But there’s an “old faithful” of comets that’s currently in our solar neighborhood, and worth checking out as well. Comet 2P/Encke (pronounced EN-key) currently shines at magnitude +7.9 and is crossing from the constellation Leo Minor into Leo this week. In fact, Encke is currently 2 magnitudes— over 6 times brighter than Comet ISON —and is currently the brightest comet in our skies. Encke is expected to top out at magnitude +7 right around perihelion towards the end of November. Encke will be a fine binocular object over the next month, and once the Moon passes Last Quarter phase on October 26th we’ll once again have a good three week window for pre-dawn comet hunting. Comet Encke made its closest pass of the Earth for this orbit on October 17th at 0.48 Astronomical Units (A.U.s) distant. This month sees its closest passage to the Earth since 2003, and the comet won’t pass closer until July 11th, 2030.

The orbital path of Comet 2P/Encke. (Credit: The NASA/JPL Solar System Dynamics Small-Body Database Browser).
The orbital path of Comet 2P/Encke. (Credit: The NASA/JPL Solar System Dynamics Small-Body Database Browser).

This will be Comet Encke’s 62nd observed perihelion passage since its discovery by Pierre Méchain in 1786. Encke has the shortest orbit of any known periodic comet, at just 3.3 years. About every 33 years we get a favorable close pass of the comet, as last occurred in 1997, and will next occur in 2030.

But this year’s apparition of Comet Encke is especially favorable for northern hemisphere observers. This is due to its relatively high orbital inclination angle of 11.8 degrees and its passage through the morning skies from north of both the ecliptic and the celestial equator. Encke is about half an A.U. ahead of us in our orbit this month, crossing roughly perpendicular to our line of sight.

Note that Encke is also running nearly parallel to Comet ISON from our vantage point as they both make the plunge through the constellation Virgo into next month. Mark your calendars: both ISON and Encke will fit into a telescopic wide field of view around November 24th in the early dawn. Photo-op!

Here are some key dates to help you in your morning quest for Comet Encke over the next month:

-October 22nd: Crosses into the constellation Leo.

-October 24th: Passes near the +5.3 magnitude star 92 Leonis.

-October 25th: Passes near the +4.5 magnitude star 93 Leonis.

-October 27th: Passes briefly into the constellation Coma Berenices.

-October 29th: Passes near the +11th magnitude galaxy M98, and crosses into the constellation Virgo.

-October 30th: Passes near the +10th magnitude galaxy pair of M84 & M86.

2P Encke from 20 Oct to 20 Nov (Created using Starry Night Education Software).
The celestial path of Comet 2P/Encke from October 20th to 20 November 20th. Note that ISON is very near Encke on the final date. Click on the image to enlarge. (Created using Starry Night Education Software).

-November 2nd: Passes between the two +5th magnitude stars of 31 and 32 Virginis.

-November 3rd: A hybrid solar eclipse occurs across the Atlantic and central Africa. It may just be possible to spot comet Encke with binoculars during the brief moments of totality.

-November 4th: Passes near the +3.4 magnitude star Auva (Delta Virginis).

-November 7th: Crosses from north to south over the celestial equator.

-November 11th:  Passes near the +5.7th star 80 Virginis.

-November 17th: The Moon reaches Full, and enters into the morning sky.

-November 18th: Passes 0.02 A.U. (just under 3 million kilometers, or 7.8 Earth-Moon distances) from the planet Mercury. A good chance for NASA’s Messenger spacecraft to perhaps snap a pic of the comet?

-November 19th: Passes 1.5 degrees from Mercury and crosses into the constellation Libra.

-November 20th: Crosses to the south of the ecliptic plane.

-November 21st: Reaches perihelion, at 0.33 AU from the Sun.

-November 24th: Comet Encke passes just 1.25 degrees from Comet ISON. Both will have a western elongation of 15 degrees from the Sun.

-November 26th: Passes near the +4.5 magnitude star Iota Librae and the +6th magnitude star 25 Librae.

-December 1st: Crosses into the constellation Scorpius.

-December 5th: Enters into view of SOHO’s LASCO C3 camera.

Note: “Passes near” on the above list indicates a passage of Comet Encke less than one angular degree (about twice the size of a Full Moon) from an interesting object, except where noted otherwise.

Binoculars are your best bet for catching sight of Comet 2P/Encke. For middle northern latitude observers, Comet Encke reaches an elevation above 20 degrees from the horizon about two hours before local sunrise. Keep in mind, Europe and the U.K. “fall back” an hour to Standard Time this coming weekend on October 27th, and most of North America follows suit on November 3rd, pushing the morning comet vigil back an hour as well.

Two other comets are both currently brighter than ISON and also merit searching for: Comet C/2013 R1 Lovejoy, at +8.7th magnitude in Canis Minor, and Comet C/2012 X1 LINEAR, currently also in Coma Berenices and undergoing a minor outburst at magnitude +8.5.

Be sure to check these celestial wonders out as we prepare for the “Main Event” of Comet ISON in November 2013!