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{{use dmy dates|date=November 2013}}
{{Use dmy dates|date=September 2019}}
{{Infobox Comet
{{Infobox Comet
| name=C/2012 F6 (Lemmon)
| name=C/2012 F6 (Lemmon)
| image=C2012F6Lemmon.jpg
| image=C2012F6Lemmon.jpg
| caption=Comet Lemmon in [[Tucana]] on 16 February 2013
| caption=Comet Lemmon in [[Tucana]] on 16 February 2013
| discoverer=A. R. Gibbs<br/>[[Mount Lemmon|Mt. Lemmon Survey]] ([[List of observatory codes#G00-G99|G96]])<ref name="MPEC2012-F88">{{cite web|date=26 March 2013|title=MPEC 2012-F88 : COMET C/2012 F6 (LEMMON)|publisher=IAU Minor Planet Center|url=http://www.minorplanetcenter.net/mpec/K12/K12F88.html|accessdate=2013-01-28}}</ref>
| discoverer=A. R. Gibbs<br/>[[Mount Lemmon|Mt. Lemmon Survey]] ([[List of observatory codes#G00-G99|G96]])<ref name="MPEC2012-F88">{{cite web|date=26 March 2013|title=MPEC 2012-F88 : COMET C/2012 F6 (LEMMON)|publisher=[[IAU Minor Planet Center]]|url=http://www.minorplanetcenter.net/mpec/K12/K12F88.html|access-date=28 January 2013}}</ref>
| discovery_date=23&nbsp;March 2012
| discovery_date=23 March 2012
| designations=
| designations=
| epoch=28 October 2012<br/>([[Julian day|JD]] 2456228.5)
| epoch=28 October 2012<br/>([[Julian day|JD]] 2456228.5)
Line 12: Line 12:
| aphelion=973.47895 AU (Q)
| aphelion=973.47895 AU (Q)
| eccentricity=0.99850 (e)
| eccentricity=0.99850 (e)
| period=~8000 [[Julian year (astronomy)|yr]]<br>(Barycentric solution for [[Epoch (astronomy)|epoch]] 2050)<ref name=barycenter/>
| period=~8000 [[Julian year (astronomy)|yr]]<br />(Barycentric solution for [[Epoch (astronomy)|epoch]] 2050)<ref name=barycenter/>
| inclination=82.60839° (i)
| inclination=82.60839° (i)
| last_p=2013-03-24.516
| last_p=2013-03-24.516
}}
}}


'''C/2012 F6 (Lemmon)''' is a [[long-period comet]] discovered in [[Leo (constellation)|Leo]] on 23 March 2012, by A. R. Gibbs<ref name="MPEC2012-F88"/> using the 1.5-m&nbsp;reflector at the [[Mount Lemmon|Mt. Lemmon Survey]], located at the summit of Mount Lemmon in the [[Catalina Mountains]] north of [[Tucson, Arizona]], USA. Initially, the object was considered to be of asteroidal nature before later observations confirmed its cometary appearance. Comet Lemmon has a highly [[orbital eccentricity|eccentric orbit]], bringing it as close to 0.73&nbsp;[[astronomical unit|AU]] from the sun at [[perihelion]] and as far as 973&nbsp;AU from the sun at [[aphelion]]. This also leads to the comet's long-period nature with an [[orbital period]] of approximately 8,000&nbsp;[[Julian year (astronomy)|years]] based on [[epoch (astronomy)|epoch]] 2050. The comet last reached perihelion on 24 March 2013.
'''C/2012 F6 (Lemmon)''' is a [[long-period comet]] discovered in [[Leo (constellation)|Leo]] on 23 March 2012, by A. R. Gibbs<ref name="MPEC2012-F88"/> using the 1.5-m&nbsp;reflector at the [[Mount Lemmon|Mt. Lemmon Survey]], located at the summit of Mount Lemmon in the [[Santa Catalina Mountains]] north of [[Tucson, Arizona]], USA. Initially, the object was considered to be of asteroidal nature before later observations confirmed its cometary appearance. Comet Lemmon has a highly [[orbital eccentricity|eccentric orbit]], bringing it as close to 0.73&nbsp;[[astronomical unit|AU]] from the Sun at [[perihelion]] and as far as 973&nbsp;AU from the Sun at [[aphelion]]. This also leads to the comet's long-period nature with an [[orbital period]] of approximately 8,000&nbsp;[[Julian year (astronomy)|years]] based on [[epoch (astronomy)|epoch]] 2050. The comet last reached perihelion on 24 March 2013.


For much of 2012, observation of Lemmon remained limited to [[Charge-coupled device|CCD imagery]], but steadily brightened throughout the course of the year. In late-November&nbsp;2012, the comet became bright enough for telescopic viewing, and had an [[apparent magnitude]] estimated at +9 by the year's end. Brightening continued into the early months of 2013 before peaking at an apparent magnitude of +5 in late March, though viewing was mostly limited to the [[Southern Hemisphere]]. On 24 March 2013, Lemmon reached its orbital perihelion and afterwards began to dim. On 20 April 2013, Lemmon crossed the [[celestial equator]] and became primarily viewable in the [[Northern Hemisphere]], though by this time the comet was significantly dimmer relative to its peak brightness.<ref name=Yoshida/>
For much of 2012, observation of Lemmon remained limited to [[Charge-coupled device|CCD imagery]], but steadily brightened throughout the course of the year. In late-November 2012, the comet became bright enough for telescopic viewing, and had an [[apparent magnitude]] estimated at +9 by the year's end. Brightening continued into the early months of 2013 before peaking at an apparent magnitude of +5 in late March, though viewing was mostly limited to the [[Southern Hemisphere]]. On 24 March 2013, Lemmon reached its orbital perihelion and afterwards began to dim. On 20 April 2013, Lemmon crossed the [[celestial equator]] and became primarily viewable in the [[Northern Hemisphere]], though by this time the comet was significantly dimmer relative to its peak brightness.<ref name=Yoshida/>


== Discovery ==
== Discovery ==
A.R.&nbsp;Gibbs of the [[Mount Lemmon Observatory]] in [[Arizona]] discovered the comet based on images acquired by the [[sky survey]]'s 1.5-m&nbsp;reflecting telescope on 23 March 2012.<ref name=CometographyLemmon /> However, Gibbs did not recognize its cometary appearance and was listed as an asteroid on the [[Minor Planet Center]]'s [[Near Earth Object]] confirmation page.<ref name=NewComets>{{cite web|title=New comets COMET P/2012 F5 (Gibbs) & C/2012 F6 (Lemmon)|url=http://schiaparelli204.wordpress.com/2012/03/26/new-comets-comet-p2012-f5-gibbs-c2012-f6-lemmon/|work="G.V.Schiaparelli" Astronomical Observatory|publisher=WordPress|accessdate=27 November 2013|author=G.V.Schiaparelli|date=March 26, 2012}}</ref> At the time, the [[apparent magnitude]] of the comet was estimated between +20.6&nbsp;and +20.8. Shortly after initial discovery, amateur astronomer Peter Birtwhistle in [[Great Shefford]] observed the comet using a 40-cm&nbsp;refracting telescope and [[Charge-coupled device|CCD]] images, estimating an apparent magnitude of +20.1 and a diameter stretching 5&nbsp;[[arc second]]s across.<ref name=CometographyLemmon>{{cite web|title=C/2012 F6 (Lemmon)|url=http://cometography.com/lcomets/2012f6.html|publisher=Cometography.com|accessdate=27 November 2013|author=Kronk, Gary W.}}</ref>
A.R.&nbsp;Gibbs of the [[Mount Lemmon Observatory]] in [[Arizona]] discovered the comet based on images acquired by the [[sky survey]]'s 1.5-m&nbsp;reflecting telescope on 23 March 2012.<ref name=CometographyLemmon /> However, Gibbs did not recognize its cometary appearance and was listed as an asteroid on the [[Minor Planet Center]]'s [[Near-Earth Object Confirmation Page]].<ref name=NewComets>{{cite web|title=New comets COMET P/2012 F5 (Gibbs) & C/2012 F6 (Lemmon)|url=http://schiaparelli204.wordpress.com/2012/03/26/new-comets-comet-p2012-f5-gibbs-c2012-f6-lemmon/|publisher="G.V.Schiaparelli" Astronomical Observatory|access-date=27 November 2013|author=G.V.Schiaparelli|date=26 March 2012}}</ref> At the time, the [[apparent magnitude]] of the comet was estimated between +20.6&nbsp;and +20.8. Shortly after initial discovery, amateur astronomer Peter Birtwhistle in [[Great Shefford]] observed the comet using a 40-cm&nbsp;refracting telescope and [[Charge-coupled device|CCD]] images, estimating an apparent magnitude of +20.1 and a diameter stretching 5&nbsp;[[arc second]]s across.<ref name=CometographyLemmon>{{cite web|title=C/2012 F6 (Lemmon)|url=http://cometography.com/lcomets/2012f6.html|publisher=Cometography.com|access-date=27 November 2013|author=Kronk, Gary W.|archive-url=https://web.archive.org/web/20130618091553/http://cometography.com/lcomets/2012f6.html#|archive-date=18 June 2013|url-status=dead}}</ref>


== Observational history ==
== Observational history ==
Following discovery, Lemmon remained a dim object but steadily brightened over the next few months. The comet was last sighted on June&nbsp;14, 2012 with an apparent magnitude estimated at +19.0 before it was lost in the sun's glare. On August&nbsp;25, the comet was analyzed to have passed an apparent 0.7&nbsp;degrees from the sun. The comet was re-sighted on October&nbsp;14 utilizing the [[RAS (Remote Astronomical Society) Observatory of New Mexico]] in [[Mayhill, New Mexico|Mayhill]], with an apparent magnitude estimated to have brightened to +15.3. The first confirmed visual observation of the comet without the use of CCD imagery was conducted by Juan Jose Gonzalez Suarez in [[Cantabria, Spain]] using a 20-cm reflector on November&nbsp;22. Several other visual confirmations were made throughout the rest of the year. By the end of 2012, the comet had a [[coma (cometary)|coma]] 5-7 [[arc minute]]s across and an apparent magnitude estimated at +9.<ref name=CometographyLemmon />
Following discovery, Lemmon remained a dim object but steadily brightened over the next few months. The comet was last sighted on 14 June 2012 with an apparent magnitude estimated at +19.0 before it was lost in the Sun's glare. On 25 August, the comet was analyzed to have passed an apparent 0.7&nbsp;degrees from the Sun. The comet was re-sighted on 14 October utilizing the [[RAS (Remote Astronomical Society) Observatory of New Mexico]] in [[Mayhill, New Mexico|Mayhill]], with an apparent magnitude estimated to have brightened to +15.3. The first confirmed visual observation of the comet without the use of CCD imagery was conducted by Juan Jose Gonzalez Suarez in [[Cantabria, Spain]] using a 20-cm reflector on 22 November. Several other visual confirmations were made throughout the rest of the year. By the end of 2012, the comet had a [[coma (cometary)|coma]] 5-7 [[arc minute]]s across and an apparent magnitude estimated at +9.<ref name=CometographyLemmon />


It was well placed for viewing in the [[southern hemisphere]] in January 2013 to observe it brightening, crossing [[Centaurus]], [[Crux]] and [[Chameleon]], and into February when it was circumpolar in [[Octans]]. By the end of February it set early evening situated in [[Phoenix (constellation)|Phoenix]], was observable well into March. After perihelion the comet should be reasonably well placed in the morning sky to observe as it fades.<ref name="CAMnotes20131">{{cite web|date=2012-12-29|title=CAMnotes 2013 No. 1 January-March|publisher=Tim Cooper, Director, Comet Asteroid and Meteor Section, Astron.Soc.Southern Africa|url=http://assa.saao.ac.za/sections/comet-meteor/ASSA_CAMnotes_2013_No_1.pdf|accessdate=2013-01-28}}</ref> The comet was visible in the [[STEREO]] heliospheric imager HI-2A starting on 17 April.<ref name=Musgrave/> C/2012 F6 crossed the [[celestial equator]] on 20 April 2013 becoming a [[northern hemisphere]] object. On 9 May 2013 the comet was near [[Gamma Pegasi]] and from a dark sky was visible in [[binoculars]] before sunrise low in the eastern sky.<ref name=Astrobob/>
It was well placed for viewing in the [[southern hemisphere]] in January 2013 to observe it brightening, crossing [[Centaurus]], [[Crux]] and [[Chamaeleon]], and into February when it was circumpolar in [[Octans]]. By the end of February it set early evening situated in [[Phoenix (constellation)|Phoenix]], was observable well into March. After perihelion the comet should be reasonably well placed in the morning sky to observe as it fades.<ref name="CAMnotes20131">{{cite web|date=29 December 2012|title=CAMnotes 2013 No. 1 January-March|publisher=Tim Cooper, Director, Comet Asteroid and Meteor Section, Astron.Soc.Southern Africa|url=http://assa.saao.ac.za/sections/comet-meteor/ASSA_CAMnotes_2013_No_1.pdf|access-date=28 January 2013}}</ref> The comet was visible in the [[STEREO]] heliospheric imager HI-2A starting on 17 April.<ref name=Musgrave/> C/2012 F6 crossed the [[celestial equator]] on 20 April 2013 becoming a [[northern hemisphere]] object. On 9 May 2013 the comet was near [[Gamma Pegasi]] and from a dark sky was visible in [[binoculars]] before sunrise low in the eastern sky.<ref name=Astrobob/>


On 11 August 2014, astronomers released studies, using the [[Atacama Large Millimeter Array|Atacama Large Millimeter/Submillimeter Array (ALMA)]] for the first time, that detailed the distribution of [[Hydrogen cyanide|HCN]], [[Hydrogen isocyanide|HNC]], [[Formaldehyde|H<sub>2</sub>CO]], and [[dust]] inside the [[Coma (cometary)|comae]] of [[comet]]s C/2012 F6 (Lemmon) and [[Comet ISON|C/2012 S1 (ISON)]].<ref name="NASA-20140811">{{cite web |last=Zubritsky |first=Elizabeth |last2=Neal-Jones |first2=Nancy |title=RELEASE 14-038 - NASA’s 3-D Study of Comets Reveals Chemical Factory at Work |url=http://www.nasa.gov/press/2014/august/goddard/nasa-s-3-d-study-of-comets-reveals-chemical-factory-at-work |date=11 August 2014 |work=[[NASA]] |accessdate=12 August 2014 }}</ref><ref name="AJL-20140811">{{cite journal |author=Cordiner, M.A. et al. |title=Mapping the Release of Volatiles in the Inner Comae of Comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON) Using the Atacama Large Millimeter/Submillimeter Array |url=http://iopscience.iop.org/2041-8205/792/1/L2/article |date=11 August 2014 |journal=[[The Astrophysical Journal]] |volume=792 |number=1 |doi=10.1088/2041-8205/792/1/L2 |accessdate=12 August 2014 }}</ref>
On 11 August 2014, astronomers released studies, using the [[Atacama Large Millimeter Array|Atacama Large Millimeter/Submillimeter Array (ALMA)]] for the first time, that detailed the distribution of [[Hydrogen cyanide|HCN]], [[Hydrogen isocyanide|HNC]], [[Formaldehyde|H<sub>2</sub>CO]], and [[dust]] inside the [[Coma (cometary)|comae]] of [[comet]]s C/2012 F6 (Lemmon) and [[Comet ISON|C/2012 S1 (ISON)]].<ref name="NASA-20140811">{{cite web |last=Zubritsky |first=Elizabeth |last2=Neal-Jones |first2=Nancy |title=RELEASE 14-038 - NASA's 3-D Study of Comets Reveals Chemical Factory at Work |url=http://www.nasa.gov/press/2014/august/goddard/nasa-s-3-d-study-of-comets-reveals-chemical-factory-at-work |date=11 August 2014 |work=[[NASA]] |access-date=12 August 2014 }}</ref><ref name="AJL-20140811">{{cite journal |author=Cordiner, M.A. |display-authors=etal |title=Mapping the Release of Volatiles in the Inner Comae of Comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON) Using the Atacama Large Millimeter/Submillimeter Array |date=11 August 2014 |journal=[[The Astrophysical Journal]] |volume=792 |pages=L2 |number=1 |doi=10.1088/2041-8205/792/1/L2 |arxiv = 1408.2458 |bibcode = 2014ApJ...792L...2C }}</ref>


== Gallery ==
== Gallery ==
<gallery>
<gallery>
Comets-Yuri-Beletsky.jpg|Comets Lemmon and [[C/2011 L4]] from [[Las Campanas Observatory]] on 1 March
Comet C2012 F6 (Lemmon) - 1 Mar 2013.jpg|Comet Lemmon on 1 March from [[Mount Burnett Observatory]]
Comet C2012 F6 (Lemmon) - 1 Mar 2013.jpg|Comet Lemmon on 1 March from [[Mount Burnett Observatory]]
Comets and Shooting Stars Dance Over Paranal.jpg|Lemmon in conjunction with C/2011&nbsp;L4 and a meteoroid trail from [[Paranal Observatory]] on 5 March
Comets and Shooting Stars Dance Over Paranal.jpg|Lemmon in conjunction with C/2011&nbsp;L4 and a meteoroid trail from [[Paranal Observatory]] on 5 March
</gallery>
</gallery>

== References ==
== References ==
{{reflist
{{reflist
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|url=http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=2012F6
|url=http://ssd.jpl.nasa.gov/horizons.cgi?find_body=1&body_group=sb&sstr=2012F6
|title=Barycentric Osculating Orbital Elements for Comet C/2012 F6 (Lemmon)
|title=Barycentric Osculating Orbital Elements for Comet C/2012 F6 (Lemmon)
|accessdate=2013-04-23}} (Solution using the Solar System [[Center of mass#Barycenter in astrophysics and astronomy|Barycenter]] and [[Barycentric coordinates (astronomy)|barycentric coordinates]]. Select Ephemeris Type:Elements and Center:@0)</ref>
|access-date=23 April 2013}} (Solution using the Solar System [[Center of mass#Barycenter in astrophysics and astronomy|Barycenter]] and [[Barycentric coordinates (astronomy)|barycentric coordinates]]. Select Ephemeris Type:Elements and Center:@0)</ref>


<ref name=Yoshida>{{cite web
<ref name=Yoshida>{{cite web
Line 51: Line 51:
|title=C/2012 F6 ( Lemmon )
|title=C/2012 F6 ( Lemmon )
|url=http://www.aerith.net/comet/catalog/2012F6/2012F6.html
|url=http://www.aerith.net/comet/catalog/2012F6/2012F6.html
|work=www.aerith.net
|work=aerith.net
|accessdate=27 April 2013}}</ref>
|access-date=27 April 2013}}</ref>


<ref name=Musgrave>{{cite web
<ref name=Musgrave>{{cite web
Line 59: Line 59:
|title=Comet C/2012 F6 Lemmon in STEREO, April 17-19 2013
|title=Comet C/2012 F6 Lemmon in STEREO, April 17-19 2013
|url=http://astroblogger.blogspot.com/2013/04/comet-c2012-f6-lemmon-in-stereo-april.html
|url=http://astroblogger.blogspot.com/2013/04/comet-c2012-f6-lemmon-in-stereo-april.html
|accessdate=30 April 2013}}</ref>
|access-date=30 April 2013}}</ref>


<ref name=Astrobob>{{cite web
<ref name=Astrobob>{{cite web
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|title=Sweeten your May mornings with Comet Lemmon
|title=Sweeten your May mornings with Comet Lemmon
|url=http://astrobob.areavoices.com/2013/05/02/sweeten-your-may-mornings-with-comet-lemmon/
|url=http://astrobob.areavoices.com/2013/05/02/sweeten-your-may-mornings-with-comet-lemmon/
|accessdate=3 May 2013}}</ref>
|access-date=3 May 2013}}</ref>


}}
}}


== External links ==
== External links ==
* [http://www.psychohistorian.org/display_article.php?id=201301231248_comet_lemmon.content South African photo gallery of C/2012 F6 ( Lemmon )] (@ psychohistorian.org)
* [https://web.archive.org/web/20130701212225/http://www.psychohistorian.org/display_article.php?id=201301231248_comet_lemmon.content South African photo gallery of C/2012 F6 ( Lemmon )] (@ psychohistorian.org)
* [http://www.aerith.net/comet/catalog/2012F6/2012F6.html C/2012 F6 ( Lemmon )] - Seiichi Yoshida @ aerith.net
* [http://www.aerith.net/comet/catalog/2012F6/2012F6.html C/2012 F6 ( Lemmon )] - Seiichi Yoshida @ aerith.net
* [http://shadowandsubstance.com/Lemmon/Lemmon.html C/2012 F6 (Lemmon) animated orbit diagram] – [http://shadowandsubstance.com/ Shadow & Substance]
* [https://web.archive.org/web/20160304044620/http://shadowandsubstance.com/Lemmon/Lemmon.html C/2012 F6 (Lemmon) animated orbit diagram] – [http://shadowandsubstance.com/ Shadow & Substance]
* [http://apod.nasa.gov/apod/ap130506.html Tails of Comet Lemmon] ([[Astronomy Picture of the Day|APOD]] 2013 May 6)
* [http://apod.nasa.gov/apod/ap130506.html Tails of Comet Lemmon] ([[Astronomy Picture of the Day|APOD]] 2013 May 6)
* [http://www.damianpeach.com/deepsky/c2012_f6_2013_05_15dp.jpg Comet Lemmon] (Damian Peach 2013 May 15)
* [http://www.damianpeach.com/deepsky/c2012_f6_2013_05_15dp.jpg Comet Lemmon] (Damian Peach 2013 May 15)
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{{Comets}}
{{Comets}}
{{2013 in space}}
{{2013 in space}}
{{Authority control}}


{{DEFAULTSORT:Lemmon, 2012 F6}}
{{DEFAULTSORT:Lemmon, 2012 F6}}
[[Category:Astronomical objects discovered in 2012|20120323]]
[[Category:Astronomical objects discovered in 2012|20120323]]
[[Category:Comets in 2013]]
[[Category:Comets in 2013|20130324]]
[[Category:Non-periodic comets]]
[[Category:Non-periodic comets]]

Latest revision as of 22:51, 19 December 2023

C/2012 F6 (Lemmon)
Comet Lemmon in Tucana on 16 February 2013
Discovery
Discovered byA. R. Gibbs
Mt. Lemmon Survey (G96)[1]
Discovery date23 March 2012
Orbital characteristics
Epoch28 October 2012
(JD 2456228.5)
Aphelion973.47895 AU (Q)
Perihelion0.73126 AU (q)
Semi-major axis487.1051 AU (a)
Eccentricity0.99850 (e)
Orbital period~8000 yr
(Barycentric solution for epoch 2050)[2]
Inclination82.60839° (i)
Last perihelion2013-03-24.516

C/2012 F6 (Lemmon) is a long-period comet discovered in Leo on 23 March 2012, by A. R. Gibbs[1] using the 1.5-m reflector at the Mt. Lemmon Survey, located at the summit of Mount Lemmon in the Santa Catalina Mountains north of Tucson, Arizona, USA. Initially, the object was considered to be of asteroidal nature before later observations confirmed its cometary appearance. Comet Lemmon has a highly eccentric orbit, bringing it as close to 0.73 AU from the Sun at perihelion and as far as 973 AU from the Sun at aphelion. This also leads to the comet's long-period nature with an orbital period of approximately 8,000 years based on epoch 2050. The comet last reached perihelion on 24 March 2013.

For much of 2012, observation of Lemmon remained limited to CCD imagery, but steadily brightened throughout the course of the year. In late-November 2012, the comet became bright enough for telescopic viewing, and had an apparent magnitude estimated at +9 by the year's end. Brightening continued into the early months of 2013 before peaking at an apparent magnitude of +5 in late March, though viewing was mostly limited to the Southern Hemisphere. On 24 March 2013, Lemmon reached its orbital perihelion and afterwards began to dim. On 20 April 2013, Lemmon crossed the celestial equator and became primarily viewable in the Northern Hemisphere, though by this time the comet was significantly dimmer relative to its peak brightness.[3]

Discovery[edit]

A.R. Gibbs of the Mount Lemmon Observatory in Arizona discovered the comet based on images acquired by the sky survey's 1.5-m reflecting telescope on 23 March 2012.[4] However, Gibbs did not recognize its cometary appearance and was listed as an asteroid on the Minor Planet Center's Near-Earth Object Confirmation Page.[5] At the time, the apparent magnitude of the comet was estimated between +20.6 and +20.8. Shortly after initial discovery, amateur astronomer Peter Birtwhistle in Great Shefford observed the comet using a 40-cm refracting telescope and CCD images, estimating an apparent magnitude of +20.1 and a diameter stretching 5 arc seconds across.[4]

Observational history[edit]

Following discovery, Lemmon remained a dim object but steadily brightened over the next few months. The comet was last sighted on 14 June 2012 with an apparent magnitude estimated at +19.0 before it was lost in the Sun's glare. On 25 August, the comet was analyzed to have passed an apparent 0.7 degrees from the Sun. The comet was re-sighted on 14 October utilizing the RAS (Remote Astronomical Society) Observatory of New Mexico in Mayhill, with an apparent magnitude estimated to have brightened to +15.3. The first confirmed visual observation of the comet without the use of CCD imagery was conducted by Juan Jose Gonzalez Suarez in Cantabria, Spain using a 20-cm reflector on 22 November. Several other visual confirmations were made throughout the rest of the year. By the end of 2012, the comet had a coma 5-7 arc minutes across and an apparent magnitude estimated at +9.[4]

It was well placed for viewing in the southern hemisphere in January 2013 to observe it brightening, crossing Centaurus, Crux and Chamaeleon, and into February when it was circumpolar in Octans. By the end of February it set early evening situated in Phoenix, was observable well into March. After perihelion the comet should be reasonably well placed in the morning sky to observe as it fades.[6] The comet was visible in the STEREO heliospheric imager HI-2A starting on 17 April.[7] C/2012 F6 crossed the celestial equator on 20 April 2013 becoming a northern hemisphere object. On 9 May 2013 the comet was near Gamma Pegasi and from a dark sky was visible in binoculars before sunrise low in the eastern sky.[8]

On 11 August 2014, astronomers released studies, using the Atacama Large Millimeter/Submillimeter Array (ALMA) for the first time, that detailed the distribution of HCN, HNC, H2CO, and dust inside the comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON).[9][10]

Gallery[edit]

References[edit]

  1. ^ a b "MPEC 2012-F88 : COMET C/2012 F6 (LEMMON)". IAU Minor Planet Center. 26 March 2013. Retrieved 28 January 2013.
  2. ^ Horizons output. "Barycentric Osculating Orbital Elements for Comet C/2012 F6 (Lemmon)". Retrieved 23 April 2013. (Solution using the Solar System Barycenter and barycentric coordinates. Select Ephemeris Type:Elements and Center:@0)
  3. ^ Yoshida, Seiichi. "C/2012 F6 ( Lemmon )". aerith.net. Retrieved 27 April 2013.
  4. ^ a b c Kronk, Gary W. "C/2012 F6 (Lemmon)". Cometography.com. Archived from the original on 18 June 2013. Retrieved 27 November 2013.
  5. ^ G.V.Schiaparelli (26 March 2012). "New comets COMET P/2012 F5 (Gibbs) & C/2012 F6 (Lemmon)". "G.V.Schiaparelli" Astronomical Observatory. Retrieved 27 November 2013.
  6. ^ "CAMnotes 2013 No. 1 January-March" (PDF). Tim Cooper, Director, Comet Asteroid and Meteor Section, Astron.Soc.Southern Africa. 29 December 2012. Retrieved 28 January 2013.
  7. ^ Musgrave, Ian (22 April 2013). "Comet C/2012 F6 Lemmon in STEREO, April 17-19 2013". Retrieved 30 April 2013.
  8. ^ King, Bob (2 May 2013). "Sweeten your May mornings with Comet Lemmon". Retrieved 3 May 2013.
  9. ^ Zubritsky, Elizabeth; Neal-Jones, Nancy (11 August 2014). "RELEASE 14-038 - NASA's 3-D Study of Comets Reveals Chemical Factory at Work". NASA. Retrieved 12 August 2014.
  10. ^ Cordiner, M.A.; et al. (11 August 2014). "Mapping the Release of Volatiles in the Inner Comae of Comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON) Using the Atacama Large Millimeter/Submillimeter Array". The Astrophysical Journal. 792 (1): L2. arXiv:1408.2458. Bibcode:2014ApJ...792L...2C. doi:10.1088/2041-8205/792/1/L2.

External links[edit]

Retrieved from "https://en.wikipedia.org/w/index.php?title=C/2012_F6_(Lemmon)&oldid=1190799006"