![]() Comet Ikeya (1964f) photographed by Dennis Milon on 27 July 1964 | |
Discovery | |
---|---|
Discovered by | Kaoru Ikeya |
Discovery date | 3 July 1964 |
Designations | |
1964f | |
Orbital characteristics [1] | |
Epoch | 1964-Jul-28.0 |
Observation arc | 56 days |
Number of observations | 36 |
Aphelion | 110.97 AU |
Perihelion | 0.822 AU |
Semi-major axis | 55.90 AU |
Eccentricity | 0.9853 |
Orbital period | 418 years |
Inclination | 171.92° |
269.95° | |
Argument of periapsis | 290.77° |
Last perihelion | 1 August 1964 |
Earth MOID | 0.041 AU |
Jupiter MOID | 0.267 AU |
Physical characteristics | |
Comet nuclear magnitude (M2) | 16.0 |
2.7 (1964 apparition) |
C/1964 N1 (Ikeya), also known as Comet 1964f, is a long-period comet discovered by Kaoru Ikeya on 3 July 1964. The comet last passed perihelion on 1 August 1964, when it reached an apparent magnitude of 2.7. [2]
The comet was discovered by the Japanese amateur astronomer Kaoru Ikeya on 3 July 1964. It was the second comet discovered by Kaoru Ikeya, after C/1963 A1. The comet was located in the morning sky, in the constellation of Taurus, at the star cluster Hyades, and had an estimated apparent magnitude of 8. The comet was moving southeast. [3]
The comet brightened during July and was observed with the naked eye on July 19 by Jim Young from the Table Mountain Observatory. It reached perihelion on 1 August 1964. By 6 August it was visible by naked eye while it passed 1-2° from Rigel. After that it was difficult to observe, being located in the morning twilight. The closest approach to Earth was on August 12, at a distance of about 0.2 AU (30 million km; 19 million mi) and at a solar elongation of 31°. On August 15 the comet was reported by S. Archer from Australia to have a magnitude of 2.8 and its tail to be 4.5 degrees long. The comet became visible from the northern hemisphere in the evening sky in late August, located low, near the horizon, and had faded noticeably. [4] [5]
On 2 September the comet was estimated to have a magnitude of 6.5 and by 12 September it was 8.5. The comet was last detected on 7 October 1964, when it had a magnitude of 10.4. [6]
The spectrum of the comet was obtained on 29 and 30 July by the Mount Wilson Observatory and photoelectric measurements made it possible to measure the relative abundances. The spectrum revealed the presence of C2, C3, CH, and CN. The N(CH)/N(CN) and N(C3)/N(CN) were both about 0.3 in the coma near the cometary nucleus. [7]
The comet is considered to be the parent body of a number of meteor showers, as it has been modeled to create four streams that intersect with the orbit of Earth. The first meteor shower to be associated with C/1964 N1 (Ikeya) is the July ξ Arietids. [8] The comet is also considered to be the parent of body of the meteor shower ϵ-Geminids and it is also possible that it could be the parent body of ξ-Geminids. All these showers are diffuse and have few meteors. [9]
The Geminids are a prolific meteor shower with 3200 Phaethon being the parent body. Because of this, it would make this shower, along with the Quadrantids, the only major meteor showers not originating from a comet. The meteors from this shower are slow, they can be seen in December and usually peak around December 4–16, with the date of highest intensity being the morning of December 14. Current showers produce up to 120–160 meteors per hour under optimal conditions, peaking around 2:00 or 3:00. Geminids were first observed in 1862, much later than other showers such as the Perseids and Leonids.
A meteor shower is a celestial event in which a number of meteors are observed to radiate, or originate, from one point in the night sky. These meteors are caused by streams of cosmic debris called meteoroids entering Earth's atmosphere at extremely high speeds on parallel trajectories. Most meteors are smaller than a grain of sand, so almost all of them disintegrate and never hit the Earth's surface. Very intense or unusual meteor showers are known as meteor outbursts and meteor storms, which produce at least 1,000 meteors an hour, most notably from the Leonids. The Meteor Data Centre lists over 900 suspected meteor showers of which about 100 are well established. Several organizations point to viewing opportunities on the Internet. NASA maintains a daily map of active meteor showers.
Comet Ikeya–Seki, formally designated C/1965 S1, 1965 VIII, and 1965f, was a long-period comet discovered independently by Kaoru Ikeya and Tsutomu Seki. First observed as a faint telescopic object on 18 September 1965, the first calculations of its orbit suggested that on October 21, it would pass just 450,000 km (280,000 mi) above the Sun's surface, and would probably become extremely bright.
12P/Pons–Brooks is a periodic comet with an orbital period of 71 years. Comets with an orbital period of 20–200 years are referred to as Halley-type comets. It is one of the brightest known periodic comets, reaching an absolute visual magnitude of about 5 in its approach to perihelion. Comet Pons-Brooks was conclusively discovered at Marseilles Observatory in July 1812 by Jean-Louis Pons, and on its next appearance in 1883 by William Robert Brooks. However it has been confirmed 12P/Pons–Brooks was observed before the 19th century.
3200 Phaethon, provisionally designated 1983 TB, is an active Apollo asteroid with an orbit that brings it closer to the Sun than any other named asteroid. For this reason, it was named after the Greek Hero, Phaëthon, son of the sun god Helios. It is 5.8 km (3.6 mi) in diameter and is the parent body of the Geminids meteor shower of mid-December. With an observation arc of 35+ years, it has a very well determined orbit. The 2017 Earth approach distance of about 10 million km was known with an accuracy of ±700 m.
A sungrazing comet is a comet that passes extremely close to the Sun at perihelion – sometimes within a few thousand kilometres of the Sun's surface. Although small sungrazers can completely evaporate during such a close approach to the Sun, larger sungrazers can survive many perihelion passages. However, the strong evaporation and tidal forces they experience often lead to their fragmentation.
The Kreutz sungrazers are a family of sungrazing comets, characterized by orbits taking them extremely close to the Sun at perihelion. At the far extreme of their orbits, aphelion, Kreutz sungrazers can be a hundred times farther from the Sun than the Earth is, while their distance of closest approach can be less than twice the Sun's radius. They are believed to be fragments of one large comet that broke up several centuries ago and are named for German astronomer Heinrich Kreutz, who first demonstrated that they were related. These sungrazers make their way from the distant outer Solar System to the inner Solar System, to their perihelion point near the Sun, and then leave the inner Solar System in their return trip to their aphelion.
13P/Olbers is a periodic comet with an orbital period of 69 years. It fits the classical definition of a Halley-type comet with a period between 20 and 200 years. The comet last passed perihelion 30 June 2024 and it was previously seen in 1956. The next perihelion is in 2094.
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.
Alpha Capricornids is a meteor shower that takes place as early as 7 July and continues until around 15 August. The meteor shower was discovered by Hungarian astronomer Miklos von Konkoly-Thege in 1871. This shower has infrequent but relatively bright meteors, with some fireballs. Parent body is comet 169P/NEAT.
332P/Ikeya–Murakami is a short-period comet with period of approximately 5.4 years first identified independently by the two Japanese amateur astronomers Kaoru Ikeya and Shigeki Murakami on November 3, 2010. Ikeya identified the comet using a 25-centimeter (10-inch) reflector at 39×, while Murakami used a 46 cm (18-inch) reflector at 78×. Photographic confirmation of the comet was obtained by Ernesto Guido and Giovanni Sostero using a Global-Rent-a-Scope (GRAS) telescope in New Mexico. Both Ikeya and Murakami discovered the comet using manual observation through optical telescopes. Such visual discoveries have become rare in recent years.
(196256) 2003 EH1 is an asteroid, classified as near-Earth object of the Amor group. It was discovered on 6 March 2003, by astronomers of the LONEOS program at Anderson Mesa Station near Flagstaff, Arizona, in the United States. Peter Jenniskens (2003–2004) proposed that it is the parent body of the Quadrantid meteor shower. 2003 EH1 is likely an extinct comet and may even be related to the comet C/1490 Y1. 2003 EH1 came to perihelion on 12 March 2014.
(155140) 2005 UD is an asteroid on an eccentric orbit, classified as a near-Earth object of the Apollo group. It was discovered on 22 October 2005, by the Catalina Sky Survey at the Catalina Station in Arizona, United States. 2005 UD is thought to be a possible fragment of 3200 Phaethon due to its similar orbit, although it is not dynamically associated with the Geminid meteor stream produced by Phaethon.
C/1962 C1 (Seki–Lines), also known as Comet Seki–Lines and 1962c, was a hyperbolic comet discovered independently by Richard D. Lines and Tsutomu Seki on 4 February 1962. The comet became very bright in April 1962, as passed its perihelion on 1 April at a distance of 0.031 AU, thus becoming the Great Comet of 1962.
C/1963 A1 (Ikeya), also known as Comet 1963I and 1963a, is a long period comet discovered by Kaoru Ikeya on 2 January 1963. The comet last passed perihelion on 21 March 1963, when it reached an apparent magnitude of 2.8.
C/1979 Y1 (Bradfield), also known as Comet 1979X and 1979l, is a long period comet discovered by William A. Bradfield on 24 December 1979. The comet has an orbital period of 308 ± 6 years and last passed perihelion on 21 December 1979. It is considered to be the parent body of the July Pegasids meteor shower. It is expected to next come to perihelion around 2287.
C/2000 WM1 (LINEAR) is a non-periodic comet discovered by LINEAR on 16 December 2000. The comet brightened to an apparent magnitude of about 2.5.
Comet Ikeya-Seki, formally designated as C/1967 Y1, is a retrograde non-periodic comet discovered by Kaoru Ikeya and Tsutomu Seki on 1967. It is the second comet discovered together by the two Japanese astronomers after C/1965 S1.
C/1911 N1 (Kiess) is a non-periodic comet discovered by Carl Clarence Kiess on 6 July 1911. The comet has been identified as the parent body of the Aurigids meteor shower.
C/1975 T2 (Suzuki–Saigusa–Mori) is a long-period comet discovered on 5 October 1975. The comet approached Earth at a distance of 0.1 AU on 31 October 1975 and became visible with naked eye. The comet has been associated with the lambda Ursae Majorids meteor shower.