Comet ISON (English Wikipedia)

MacRobert, Alan (28 November 2013). "Latest Updates on Comet ISON". Sky & Telescope. Archived from the original on 28 November 2013. Retrieved 28 November 2013.
Levay, Zolt (20 December 2013). "BREAKING NEWS: Comet ISON Is Still Dead". Hubblesite.org. Archived from the original on 21 December 2013. Retrieved 21 December 2013.
Bortle, John (13 June 2013). "Comet ISON approaches". Sky & Telescope. Archived from the original on 16 June 2013. Retrieved 14 June 2013.

areavoices.com

astrobob.areavoices.com

King, Bob (19 October 2012). "Wassup with comets Hergenrother, L4 PanSTARRS and S1 ISON". Astro Bob. Areavoices.com. Archived from the original on 8 February 2013. Retrieved 1 January 2013.
King, Bob (11 November 2013). "Mercury enters early morning comet traffic jam". Astro Bob. Areavoices.com. Archived from the original on 15 November 2013. Retrieved 18 November 2013.

arm.ac.uk

star.arm.ac.uk

Sekhar, A. & Asher, D. J. (January 2014). "Meteor showers on Earth from sungrazing comets" (PDF). Monthly Notices of the Royal Astronomical Society. 437 (1): L71–L75. arXiv:1310.3171. Bibcode:2014MNRAS.437L..71S. doi:10.1093/mnrasl/slt143. Archived from the original (PDF) on 2 December 2013. Retrieved 12 October 2013.

arxiv.org

Zdenek, Sekanina & Kracht, Rainer (2014). "Disintegration of Comet C/2012 S1 (ISON) Shortly Before Perihelion: Evidence from Independent Data Sets". arXiv:1404.5968v4 [astro-ph.EP].
de la Fuente Marcos, Carlos; et al. (6 February 2018). "Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies". Monthly Notices of the Royal Astronomical Society Letters. 476 (1): L1–L5. arXiv:1802.00778. Bibcode:2018MNRAS.476L...1D. doi:10.1093/mnrasl/sly019.
Kaib, Nathan A.; et al. (2009). "2006 SQ₃₇₂: A Likely Long-Period Comet from the Inner Oort Cloud". The Astrophysical Journal. 695 (1): 268–275. arXiv:0901.1690. Bibcode:2009ApJ...695..268K. doi:10.1088/0004-637X/695/1/268. S2CID 16987581.
Sekhar, A. & Asher, D. J. (January 2014). "Meteor showers on Earth from sungrazing comets" (PDF). Monthly Notices of the Royal Astronomical Society. 437 (1): L71–L75. arXiv:1310.3171. Bibcode:2014MNRAS.437L..71S. doi:10.1093/mnrasl/slt143. Archived from the original (PDF) on 2 December 2013. Retrieved 12 October 2013.
Ferrín, Ignacio (2013). "Secular Light Curves of Comets C/2011 L4 Panstarrs and C/2012 S1 ISON Compared to 1P/Halley". arXiv:1302.4621v1 [astro-ph].
Cordiner, M. A.; et al. (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 Letters. 792 (1). L2. arXiv:1408.2458. Bibcode:2014ApJ...792L...2C. doi:10.1088/2041-8205/792/1/L2. S2CID 26277035.

astroblogger.blogspot.com.au

Musgrave, Ian (28 November 2013). "Is Comet C/2012 S1 ISON on Track?". Astroblog. Retrieved 28 November 2013.

astronomy.com

Bakich, Michael E. (25 September 2012). "Comet ISON will light up the sky". Astronomy. Archived from the original on 13 May 2019. Retrieved 28 September 2012.

astronomynow.com

Grego, Peter (25 September 2012). "New comet might blaze brighter than the full Moon". Astronomy Now. Archived from the original on 27 September 2012. Retrieved 28 September 2012.

baltimoresun.com

Rasmussen, Frederick N. (5 December 2013). "Back Story: Comet Kohoutek was another flameout". The Baltimore Sun. Archived from the original on 7 November 2018. Retrieved 3 February 2014.

brucegary.net

Gary, Bruce (12 August 2013). "Comet ISON Observations by an Amateur Observer: Recovery Observation". BruceGary.net. Retrieved 4 October 2013.

canada.com

o.canada.com

Dickinson, David (25 September 2012). "Will we have a Christmas comet in 2013?". Canada.com. Archived from the original on 26 December 2012. Retrieved 30 September 2012.

cometography.com

Kronk, Gary W. "C/2012 S1 (ISON)". Cometography.com. Archived from the original on 28 September 2012. Retrieved 12 December 2013.

discovermagazine.com

blogs.discovermagazine.com

Powell, Cory S. (5 January 2014). "10 Lessons from the "Comet of the Century"". Discover. Archived from the original on 7 January 2014. Retrieved 3 February 2014.

doi.org

de la Fuente Marcos, Carlos; et al. (6 February 2018). "Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies". Monthly Notices of the Royal Astronomical Society Letters. 476 (1): L1–L5. arXiv:1802.00778. Bibcode:2018MNRAS.476L...1D. doi:10.1093/mnrasl/sly019.
Kaib, Nathan A.; et al. (2009). "2006 SQ₃₇₂: A Likely Long-Period Comet from the Inner Oort Cloud". The Astrophysical Journal. 695 (1): 268–275. arXiv:0901.1690. Bibcode:2009ApJ...695..268K. doi:10.1088/0004-637X/695/1/268. S2CID 16987581.
Sekhar, A. & Asher, D. J. (January 2014). "Meteor showers on Earth from sungrazing comets" (PDF). Monthly Notices of the Royal Astronomical Society. 437 (1): L71–L75. arXiv:1310.3171. Bibcode:2014MNRAS.437L..71S. doi:10.1093/mnrasl/slt143. Archived from the original (PDF) on 2 December 2013. Retrieved 12 October 2013.
Cordiner, M. A.; et al. (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 Letters. 792 (1). L2. arXiv:1408.2458. Bibcode:2014ApJ...792L...2C. doi:10.1088/2041-8205/792/1/L2. S2CID 26277035.

esa.int

soho.esac.esa.int

"LASCO image dated 27 November 16:08". ESA.int. 27 November 2013. Archived from the original on 2 December 2013. Retrieved 27 November 2013.

harvard.edu

ui.adsabs.harvard.edu

de la Fuente Marcos, Carlos; et al. (6 February 2018). "Where the Solar system meets the solar neighbourhood: patterns in the distribution of radiants of observed hyperbolic minor bodies". Monthly Notices of the Royal Astronomical Society Letters. 476 (1): L1–L5. arXiv:1802.00778. Bibcode:2018MNRAS.476L...1D. doi:10.1093/mnrasl/sly019.
Kaib, Nathan A.; et al. (2009). "2006 SQ₃₇₂: A Likely Long-Period Comet from the Inner Oort Cloud". The Astrophysical Journal. 695 (1): 268–275. arXiv:0901.1690. Bibcode:2009ApJ...695..268K. doi:10.1088/0004-637X/695/1/268. S2CID 16987581.
Sekhar, A. & Asher, D. J. (January 2014). "Meteor showers on Earth from sungrazing comets" (PDF). Monthly Notices of the Royal Astronomical Society. 437 (1): L71–L75. arXiv:1310.3171. Bibcode:2014MNRAS.437L..71S. doi:10.1093/mnrasl/slt143. Archived from the original (PDF) on 2 December 2013. Retrieved 12 October 2013.
Golubaev, A. V.; et al. (May 2014). "Preliminary Results of the Observations of a Meteor Shower of Comet C/2012 S1 (ISON) in January 2014" (PDF). Astronomicheskii Tsirkulyar. 1611: 1–4. Bibcode:2014ATsir1611....1G.
Cordiner, M. A.; et al. (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 Letters. 792 (1). L2. arXiv:1408.2458. Bibcode:2014ApJ...792L...2C. doi:10.1088/2041-8205/792/1/L2. S2CID 26277035.

csc.eps.harvard.edu

"Comet C/2012 S1 (ISON)". Cometary Science Archive. Central Bureau for Astronomical Telegrams, International Astronomical Union. Retrieved 12 December 2013.
"Comet C/2012 S1 (ISON)". Central Bureau for Astronomical Telegrams. Central Bureau Electronic Telegrams. International Astronomical Union. 24 September 2012. Electronic Telegram No. 3258.
"Comet C/2012 S1 (ISON)". Harvard University Cometary Science Archive. 2012. Retrieved 22 November 2013.

scully.cfa.harvard.edu

"Elements and Ephemeris for C/2012 S1 (ISON)". IAU Minor Planet Center. Archived from the original on 5 May 2016. Retrieved 23 April 2013.

icq.eps.harvard.edu

"Brightest comets seen since 1935". International Comet Quarterly. Archived from the original on 28 December 2011. Retrieved 28 September 2012.

hubblesite.org

Levay, Zolt (20 December 2013). "BREAKING NEWS: Comet ISON Is Still Dead". Hubblesite.org. Archived from the original on 21 December 2013. Retrieved 21 December 2013.

isoncampaign.org

Battams, Karl (28 November 2013). "Schrödinger's Comet". CIOC. Archived from the original on 5 February 2014. Retrieved 28 November 2013.
Battams, Karl (29 November 2013). "In ISON's Wake, a Trail of Questions". CIOC. Archived from the original on 5 February 2014. Retrieved 30 November 2013.
"comet ISON's current status". NASA Comet ISON Observing Campaign. 30 November 2013. Archived from the original on 22 January 2014. Retrieved 1 December 2013.
Battams, Karl (2 December 2013). "In Memoriam". CIOC. Archived from the original on 3 December 2013. Retrieved 2 December 2013.
"Let History Be Our Guide?". Comet ISON Observing Campaign. 22 July 2013. Archived from the original on 6 December 2013. Retrieved 2 August 2013.
González, Juan José (31 October 2013). "C/2012 S1, C/2012 X1, C/2013 R1, 2P". Yahoo! Groups: Comet Observations. Archived from the original on 4 November 2013. Retrieved 31 October 2013. (just a few days ago we saw the first reports of ground-based observers being able to view ISON through binoculars) Archived 19 February 2014 at the Wayback Machine
Battams, Karl (27 November 2013). "Very quick update". CIOC. Archived from the original on 5 February 2014. Retrieved 28 November 2013.

minorplanetcenter.net

"MPEC 2013-W16 : COMET C/2012 S1 (ISON)". IAU Minor Planet Center. 26 November 2013. Retrieved 27 November 2013.
"MPEC 2012-S63: Comet C/2012 S1 (ISON)". IAU Minor Planet Center. 24 September 2012. CK12S010. Retrieved 24 September 2012.

msu.ru

comet.sai.msu.ru

Golubaev, A. V.; et al. (May 2014). "Preliminary Results of the Observations of a Meteor Shower of Comet C/2012 S1 (ISON) in January 2014" (PDF). Astronomicheskii Tsirkulyar. 1611: 1–4. Bibcode:2014ATsir1611....1G.

nasa.gov

ssd.jpl.nasa.gov

C/2012 S1 (ISON) had an epoch 1600 barycentric semi-major axis of −145127 and would have an inbound v_infinite of 0.2 km/s at 50000 au:
v=42.1219√1/(distance of 50000) − 0.5/(semi-major axis of −145127)
Horizons output. "Barycentric Osculating Orbital Elements for Comet C/2012 S1 (ISON)". Solution using the Solar System Barycenter. Ephemeris Type:Elements and Center:@0 (To be outside planetary region, inbound epoch 1950 and outbound epoch 2050. With $e>1$ both inbound and outbound, it has no orbital period)
"Horizons Batch for 2013-Nov-28 perihelion velocity". JPL Horizons. Retrieved 22 January 2023.
"JPL Close-Approach Data: C/2012 S1 (ISON)". NASA.gov. 27 September 2021. Retrieved 25 November 2012.

nasa.gov

Reddy, Francis (29 March 2013). "NASA's Swift Sizes Up Comet ISON". NASA.gov. Retrieved 23 April 2013.
Fox, Karen C. (10 December 2013). "Fire vs. Ice: The Science of ISON at Perihelion". NASA.gov. Archived from the original on 17 January 2014. Retrieved 11 December 2013.
Fox, Karen C. (2 December 2013). "NASA Investigating the Life of Comet ISON". NASA.gov. Archived from the original on 30 December 2019. Retrieved 2 December 2013.
Zubritsky, Elizabeth & Neal-Jones, Nancy (11 August 2014). "NASA's 3-D Study of Comets Reveals Chemical Factory at Work". NASA. Release 14-038. Retrieved 12 August 2014.

solarsystem.nasa.gov

"NASA's Spitzer Observes Gas Emission From Comet ISON". NASA. 23 July 2013. Archived from the original on 4 August 2013. Retrieved 1 August 2013.
"BRRISON". NASA Solar System Exploration. 29 September 2013. Archived from the original on 6 July 2013. Retrieved 28 January 2015.

science.nasa.gov

Phillips, Tony (19 April 2013). "Comet ISON Meteor Shower". NASA.gov. Archived from the original on 21 September 2013. Retrieved 23 April 2013.

stereo-ssc.nascom.nasa.gov

"Anticipated STEREO observations of Comet ISON". NASA STEREO Science Center. 27 February 2013. Retrieved 28 April 2013.

navy.mil

sungrazer.nrl.navy.mil

"ISON Updates from the CIOC". Sungrazing Comets. U.S. Navy. Archived from the original on 12 January 2014. Retrieved 21 July 2013.

nbcnews.com

Boyle, Alan (30 November 2013). "Comet ISON's leftovers fade away, right before a satellite's eyes". NBC News. Retrieved 9 December 2013.

neoastrosoft.com

"Open the Great Comet Comet C/2012 S1 (ISON)". Neoastrasoft.com. 12 October 2012. Archived from the original on 4 November 2016. Retrieved 4 November 2016.

newscientist.com

Hecht, Jeff (25 September 2012). "Newly spotted comet may outshine the full moon". New Scientist. Archived from the original on 26 September 2012. Retrieved 28 September 2012.

nightskyinfo.com

"Comet ISON – Latest Updates, FAQ and Viewing Guide". Nightskyinfo.com. Retrieved 22 July 2013.
"Comet ISON – Latest Updates, FAQ and Viewing Guide". Nightskyinfo.com. Retrieved 18 June 2013.

nytimes.com

Chang, Kenneth (29 November 2013). "Comet ISON, Presumed Dead, Shows New Life". The New York Times. Retrieved 29 November 2013.
Chang, Kenneth (27 November 2013). "Comet Nears Sun, Offering Planetary Clues". The New York Times. Retrieved 27 November 2013.

remanzacco.blogspot.it

Guido, Ernesto; et al. (24 September 2012). "New Comet: C/2012 S1 (ISON)". Associazione Friulana di Astronomia e Meteorologia. Retrieved 24 September 2012.

semanticscholar.org

api.semanticscholar.org

Kaib, Nathan A.; et al. (2009). "2006 SQ₃₇₂: A Likely Long-Period Comet from the Inner Oort Cloud". The Astrophysical Journal. 695 (1): 268–275. arXiv:0901.1690. Bibcode:2009ApJ...695..268K. doi:10.1088/0004-637X/695/1/268. S2CID 16987581.
Cordiner, M. A.; et al. (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 Letters. 792 (1). L2. arXiv:1408.2458. Bibcode:2014ApJ...792L...2C. doi:10.1088/2041-8205/792/1/L2. S2CID 26277035.

skyandtelescope.com

MacRobert, Alan (28 November 2013). "Latest Updates on Comet ISON". Sky & Telescope. Archived from the original on 28 November 2013. Retrieved 28 November 2013.
Flanders, Tony (14 November 2013). "Comet ISON Comes to Life!". Sky & Telescope. Retrieved 14 November 2013.
Bortle, John (13 June 2013). "Comet ISON approaches". Sky & Telescope. Archived from the original on 16 June 2013. Retrieved 14 June 2013.
Beatty, Kelly (27 September 2012). "A "Dream Comet" Heading Our Way?". Sky & Telescope. Archived from the original on 30 September 2012. Retrieved 28 September 2012.

slate.com

Plait, Phil (21 November 2013). "12 Cool Facts about Comet ISON". Slate. Retrieved 28 November 2013.
Plait, Phil (28 November 2013). "ISON Update for 22:00 UTC Nov. 28". Slate. Retrieved 28 November 2013.
Plait, Phil (25 November 2013). "Is Comet ISON Heading for Interstellar Space?". Slate. Retrieved 25 November 2013.

space.com

Rao, Joe (25 September 2012). "Newfound Comet Could Look Spectacular in 2013". Space.com. Retrieved 28 September 2012.

spacetelescope.org

"Hubble captures Comet ISON". SpaceTelescope.org. 24 April 2013. Retrieved 30 April 2013.

theguardian.com

Pickup, Alan (13 October 2013). "Starwatch: The brightening of ISON". The Guardian. Retrieved 16 October 2013.

twitter.com

Battams, Karl (28 November 2013). "Alright we're calling it..." Twitter.com.
Battams, Karl (30 November 2013). "If #ISON had a nucleus ..." Twitter.com.

uahirise.org

Delamere, Alan & McEwen, Alfred. "First HiRISE Images of Comet ISON". University of Arizona (HiRISE). Retrieved 2 October 2013.

universetoday.com

Atkinson, Nancy (25 September 2012). "New 'Sun-Skirting' Comet Could Provide Dazzling Display in 2013". Universe Today. Retrieved 28 September 2012.
Dickinson, David (23 September 2013). "Comet ISON: A Viewing Guide from Now to Perihelion". Universe Today. Retrieved 4 October 2013.
Atkinson, Nancy (24 October 2013). "Why Is Comet ISON Green?". Universe Today. Retrieved 31 October 2013.
Atkinson, Nancy (15 November 2013). "Whoa. Take a Look at Comet ISON Now". Universe Today. Retrieved 18 November 2013.
Atkinson, Nancy (30 July 2013). "Rumors of Comet ISON 'Fizzling' May be Greatly Exaggerated". Universe Today. Retrieved 20 October 2013.

usra.edu

lpi.usra.edu

Trigo-Rodríguez, J. M.; et al. (2013). Post-discovery Photometric Follow-up of Sungrazing Comet C/2012 S1 ISON (PDF). 44th Lunar and Planetary Science Conference. 18–22 March 2013. The Woodlands, Texas. #1576.

web.archive.org

"Open the Great Comet Comet C/2012 S1 (ISON)". Neoastrasoft.com. 12 October 2012. Archived from the original on 4 November 2016. Retrieved 4 November 2016.
Fox, Karen C. (10 December 2013). "Fire vs. Ice: The Science of ISON at Perihelion". NASA.gov. Archived from the original on 17 January 2014. Retrieved 11 December 2013.
Battams, Karl (28 November 2013). "Schrödinger's Comet". CIOC. Archived from the original on 5 February 2014. Retrieved 28 November 2013.
Battams, Karl (29 November 2013). "In ISON's Wake, a Trail of Questions". CIOC. Archived from the original on 5 February 2014. Retrieved 30 November 2013.
"comet ISON's current status". NASA Comet ISON Observing Campaign. 30 November 2013. Archived from the original on 22 January 2014. Retrieved 1 December 2013.
Battams, Karl (2 December 2013). "In Memoriam". CIOC. Archived from the original on 3 December 2013. Retrieved 2 December 2013.
Fox, Karen C. (2 December 2013). "NASA Investigating the Life of Comet ISON". NASA.gov. Archived from the original on 30 December 2019. Retrieved 2 December 2013.
Kronk, Gary W. "C/2012 S1 (ISON)". Cometography.com. Archived from the original on 28 September 2012. Retrieved 12 December 2013.
Grego, Peter (25 September 2012). "New comet might blaze brighter than the full Moon". Astronomy Now. Archived from the original on 27 September 2012. Retrieved 28 September 2012.
Hecht, Jeff (25 September 2012). "Newly spotted comet may outshine the full moon". New Scientist. Archived from the original on 26 September 2012. Retrieved 28 September 2012.
Bortle, J. (24 September 2012). "Re: C/2012 S1 (ISON), Some Further Thoughts". comets-ml (Mailing list). Yahoo! Groups. Archived from the original on 28 September 2012. Retrieved 5 October 2012.
"Let History Be Our Guide?". Comet ISON Observing Campaign. 22 July 2013. Archived from the original on 6 December 2013. Retrieved 2 August 2013.
King, Bob (19 October 2012). "Wassup with comets Hergenrother, L4 PanSTARRS and S1 ISON". Astro Bob. Areavoices.com. Archived from the original on 8 February 2013. Retrieved 1 January 2013.
Phillips, Tony (19 April 2013). "Comet ISON Meteor Shower". NASA.gov. Archived from the original on 21 September 2013. Retrieved 23 April 2013.
Sekhar, A. & Asher, D. J. (January 2014). "Meteor showers on Earth from sungrazing comets" (PDF). Monthly Notices of the Royal Astronomical Society. 437 (1): L71–L75. arXiv:1310.3171. Bibcode:2014MNRAS.437L..71S. doi:10.1093/mnrasl/slt143. Archived from the original (PDF) on 2 December 2013. Retrieved 12 October 2013.
Bakich, Michael E. (25 September 2012). "Comet ISON will light up the sky". Astronomy. Archived from the original on 13 May 2019. Retrieved 28 September 2012.
"NASA's Spitzer Observes Gas Emission From Comet ISON". NASA. 23 July 2013. Archived from the original on 4 August 2013. Retrieved 1 August 2013.
"Elements and Ephemeris for C/2012 S1 (ISON)". IAU Minor Planet Center. Archived from the original on 5 May 2016. Retrieved 23 April 2013.
"BRRISON". NASA Solar System Exploration. 29 September 2013. Archived from the original on 6 July 2013. Retrieved 28 January 2015.
González, Juan José (31 October 2013). "C/2012 S1, C/2012 X1, C/2013 R1, 2P". Yahoo! Groups: Comet Observations. Archived from the original on 4 November 2013. Retrieved 31 October 2013. (just a few days ago we saw the first reports of ground-based observers being able to view ISON through binoculars) Archived 19 February 2014 at the Wayback Machine
King, Bob (11 November 2013). "Mercury enters early morning comet traffic jam". Astro Bob. Areavoices.com. Archived from the original on 15 November 2013. Retrieved 18 November 2013.
"LASCO image dated 27 November 16:08". ESA.int. 27 November 2013. Archived from the original on 2 December 2013. Retrieved 27 November 2013.
Battams, Karl (27 November 2013). "Very quick update". CIOC. Archived from the original on 5 February 2014. Retrieved 28 November 2013.
"ISON Updates from the CIOC". Sungrazing Comets. U.S. Navy. Archived from the original on 12 January 2014. Retrieved 21 July 2013.
"Brightest comets seen since 1935". International Comet Quarterly. Archived from the original on 28 December 2011. Retrieved 28 September 2012.
Beatty, Kelly (27 September 2012). "A "Dream Comet" Heading Our Way?". Sky & Telescope. Archived from the original on 30 September 2012. Retrieved 28 September 2012.
Dickinson, David (25 September 2012). "Will we have a Christmas comet in 2013?". Canada.com. Archived from the original on 26 December 2012. Retrieved 30 September 2012.
Rasmussen, Frederick N. (5 December 2013). "Back Story: Comet Kohoutek was another flameout". The Baltimore Sun. Archived from the original on 7 November 2018. Retrieved 3 February 2014.
Powell, Cory S. (5 January 2014). "10 Lessons from the "Comet of the Century"". Discover. Archived from the original on 7 January 2014. Retrieved 3 February 2014.

yahoo.com

tech.groups.yahoo.com

Bortle, J. (24 September 2012). "Re: C/2012 S1 (ISON), Some Further Thoughts". comets-ml (Mailing list). Yahoo! Groups. Archived from the original on 28 September 2012. Retrieved 5 October 2012.

groups.yahoo.com

González, Juan José (31 October 2013). "C/2012 S1, C/2012 X1, C/2013 R1, 2P". Yahoo! Groups: Comet Observations. Archived from the original on 4 November 2013. Retrieved 31 October 2013. (just a few days ago we saw the first reports of ground-based observers being able to view ISON through binoculars) Archived 19 February 2014 at the Wayback Machine