Discovery | |
---|---|
Discovered by | Andrea Boattini Mt. Lemmon Survey (G96) [1] |
Discovery date | 20 November 2007 |
Orbital characteristics | |
Epoch | 28 May 2008 (JD 2454614.5) |
Aphelion | ~3,163 AU [2] (Q) |
Perihelion | 0.84972 AU (q) |
Semi-major axis | ~1,582 AU [2] (a) |
Eccentricity | 1.00015 [3] |
Orbital period | ~63,000 yr [2] [4] |
Inclination | 9.8903° |
Last perihelion | 2008-Jun-24 [3] |
Next perihelion | unknown |
Earth MOID | 0.0178 AU (2,660,000 km) |
C/2007 W1 (Boattini) is a long-period comet discovered on 20 November 2007, by Andrea Boattini at the Mt. Lemmon Survey. [1] At the peak the comet had an apparent magnitude around 5. [5]
On 3 April 2008, when C/2007 W1 was 0.66AU from the Earth and 1.7AU from the Sun, the coma (expanding tenuous dust atmosphere) of the comet was estimated to be as large as 10 arcminutes. [6] This made the coma roughly 290,000 km in diameter. [7]
On 12 June 2008, the comet passed within about 0.21005 AU (31,423,000 km ; 19,525,000 mi ) of the Earth. [8] The comet came to perihelion (closest approach to the Sun) on 24 June 2008 at a distance of 0.8497 AU. [3]
The comet has an observation arc of 285 days [3] allowing a good estimate of the orbit. The orbit of a long-period comet is properly obtained when the osculating orbit is computed at an epoch after leaving the planetary region and is calculated with respect to the center of mass of the Solar System. Using JPL Horizons, the barycentric orbital elements for epoch 2020-Jan-01 generate a semi-major axis of 1,582 AU, an apoapsis distance of 3,163 AU, and a period of approximately 63,000 years. [2] [4]
Before entering the planetary region, C/2007 W1 had a hyperbolic trajectory. [2] The comet was probably in the outer Oort cloud with a loosely bound chaotic orbit that was easily perturbed by passing stars.
A meteor shower known as the Daytime Craterids has been associated with C/2007 W1, thus becoming the first hyperbolic comet associated with a meteor shower. The meteor shower produced daytime outbursts in 2003 and 2009, with a Zenithal Hourly Rate of over 30 meteors per hour observed with radar. [9]
Comet C/2006 M4 (SWAN) is a non-periodic comet discovered in late June 2006 by Robert D. Matson of Irvine, California and Michael Mattiazzo of Adelaide, South Australia in publicly available images of the Solar and Heliospheric Observatory (SOHO). These images were captured by the Solar Wind ANisotropies (SWAN) Lyman-alpha all-sky camera on board the SOHO. The comet was officially announced after a ground-based confirmation by Robert McNaught on July 12.
Comet C/1861 G1 (Thatcher) is a long-period comet with roughly a 422-year orbit that is expected to return around 2283. It was discovered by A. E. Thatcher. It is responsible for the April Lyrid meteor shower. Carl Wilhelm Baeker also independently found this comet. The comet passed about 0.335 AU from the Earth on 5 May 1861 and last came to perihelion on 3 June 1861.
45P/Honda–Mrkos–Pajdušáková is a short-period comet discovered by Minoru Honda December 3, 1948. It is named after Minoru Honda, Antonín Mrkos, and Ľudmila Pajdušáková. The object revolves around the Sun on an elliptical orbit with a period of 5.25 years. The nucleus is 1.3 kilometers in diameter. On August 19 and 20, 2011, it became the fifteenth comet detected by ground radar telescope.
206P/Barnard–Boattini was the first comet to be discovered by photographic means. The American astronomer Edward Emerson Barnard did so on the night of October 13, 1892. After this apparition this comet was lost and was thus designated D/1892 T1. Ľuboš Neslušan suggests that 14P/Wolf and this comet are siblings which stem from a common parent comet.
C/2007 F1 (LONEOS) is a hyperbolic comet discovered on March 19, 2007 as part as the Lowell Observatory Near Earth Object Search (LONEOS). The comet reached perihelion, or closest approach to the sun on October 28, 2007.
C/1992 J1 (Spacewatch) is a comet that was discovered 1 May 1992 by David Rabinowitz of the Spacewatch Project. This was the first comet to be discovered using an automated system.
C/1980 E1 is a non-periodic comet discovered by Edward L. G. Bowell on 11 February 1980 and which came closest to the Sun (perihelion) in March 1982. It is leaving the Solar System on a hyperbolic trajectory due to a close approach to Jupiter. In the 43 years since its discovery only two objects with higher eccentricities have been identified, 1I/ʻOumuamua (1.2) and 2I/Borisov (3.35).
C/2007 Q3 , is an Oort cloud comet that was discovered by Donna Burton in 2007 at Siding Spring Observatory in New South Wales, Australia. Siding Spring came within 1.2 astronomical units of Earth and 2.25 AU of the Sun on October 7, 2009. The comet was visible with binoculars until January 2010.
C/2000 W1 (Utsunomiya–Jones) is a long-period comet from the Oort cloud discovered on November 18, 2000, by Syogo Utsunomiya and Albert F. A. L. Jones. The comet reached up to apparent magnitude 5.5, but was only 27 degrees from the Sun in mid-December 2000.
C/1999 F1 (Catalina) is one of the longest known long-period comets. It was discovered on March 23, 1999, by the Catalina Sky Survey. The current perihelion point is outside of the inner Solar System which helps reduce planetary perturbations to this outer Oort cloud object and keep the inbound and outbound orbital periods similar.
255P/Levy, formerly P/2006 T1 and P/2011 Y1, is a periodic comet with an orbital period of 5.25 years. It last came to perihelion on 14 January 2012. During the 2006 passage the comet achieved an apparent magnitude of ~9.5. Levy (PK06T010) was believed to have been recovered on 3 June 2011 at magnitude 19.8, but other observatories were unable to confirm a recovery. It was most likely a false positive because of large residuals. Levy was recovered on 17 December 2011 at magnitude 19.8, and given the second designation 2011 Y1. It was then numbered.
C/1999 S4 (LINEAR) was a long-period comet discovered on September 27, 1999, by LINEAR.
Aurigids is a meteor shower occurring primarily within September.
C/2013 V5 (Oukaimeden) is a retrograde Oort cloud comet discovered on 12 November 2013 by Oukaimeden Observatory at an apparent magnitude of 19.4 using a 0.5-meter (20 in) reflecting telescope.
C/2013 US10 (Catalina) is an Oort cloud comet discovered on 31 October 2013 by the Catalina Sky Survey at an apparent magnitude of 19 using a 0.68-meter (27 in) Schmidt–Cassegrain telescope. From September 2015 to February 2016 the comet was around apparent magnitude 6. The comet took around a million years to complete half an orbit from its furthest distance in the Oort cloud and should be ejected from the Solar System over many millions of years.
C/2017 U7 (PanSTARRS) is a hyperbolic comet, first observed on 29 October 2017 by astronomers of the Pan-STARRS facility at Haleakala Observatory, Hawaii, United States when the object was 7.8 AU (1.2 billion km) from the Sun. Despite being discovered only 10 days after interstellar asteroid 1I/'Oumuamua, it was not announced until March 2018 as its orbit is not strongly hyperbolic beyond most Oort Cloud comets. Based on the absolute magnitude of 10.6, it may measure tens of kilometers in diameter. As of August 2018, there is only 1 hyperbolic asteroid known, ʻOumuamua, but hundreds of hyperbolic comets are known.
C/2018 C2 (Lemmon) is a hyperbolic comet. It was first observed on 5 February 2018 by the Mount Lemmon Survey conducted at the Mount Lemmon Observatory near Tucson, Arizona, in the United States. The discovery was announced on 4 March 2018 along with another hyperbolic object, A/2017 U7. Based on the absolute magnitude of 15.1, it may measure several kilometers in diameter. On 22 March 2018 it was determined to be a hyperbolic comet.
C/2021 A1 (Leonard) was a long period comet that was discovered by G. J. Leonard at the Mount Lemmon Observatory on 3 January 2021 when the comet was 5 AU (750 million km) from the Sun. It had a retrograde orbit. The nucleus was about 1 km across. It came within 4 million km (2.5 million mi) of Venus, the closest-known cometary approach to Venus.
C/2010 U3 (Boattini) is the hyperbolic comet with the longest observation arc and took around a million years to complete half an orbit from its furthest distance in the Oort cloud. It was discovered on 31 October 2010 by Andrea Boattini in images taken with the Mount Lemmon Survey's 1.5-m reflector. The perihelion point is outside of the inner Solar System.