C / 2014 E2 (Jacques)

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C / 2014 E2 (Jacques) [i]
C / 2014 E2 (Jacques) on August 24, 2014
C / 2014 E2 (Jacques) on August 24, 2014
Properties of the orbit ( animation )
Epoch:  August 1st, 2014 ( JD 2,456,870.5)
Orbit type long-period
Numerical eccentricity 0.999035
Perihelion 0.664 AU
Aphelion 1376 AU
Major semi-axis 688.3 AU
Sidereal period ~ 18,000  a
Inclination of the orbit plane 156.4 °
Perihelion 2nd July 2014
Orbital velocity in the perihelion 51.7 km / s
history
Explorer C. Jacques Lage de Faria, E. Pimentel, J. Ribeiro de Barros
Date of discovery March 13, 2014
Source: Unless otherwise stated, the data comes from JPL Small-Body Database Browser . Please also note the note on comet articles .

C / 2014 E2 (Jacques) is a comet that was observed in 2014.

Discovery and observation

The comet was recorded on March 13, 2014 by Cristóvão Jacques Lage de Faria, Eduardo Pimentel and João Ribeiro de Barros on CCD images with the help of the 0.45 m reflecting telescope of the Southern Observatory for Near Earth Asteroids Research ( SONEAR ) in Discovered near Oliveira ( Minas Gerais ) in Brazil . At this point in time the comet was in the constellation Centaur and had a brightness of 14.7 mag.

Images of the comet on the day of its discovery

First estimates only indicated that the comet would not be brighter than 10 mag at the time of its closest approach to the sun and earth in July / August. However, it already reached this brightness at the beginning of April and it was therefore hoped that it could achieve a brightness of up to 3 or 4 mag. When the comet was first seen again on July 11, 2014 after passing the sun, its brightness was only 6.5 mag and it was only visible in binoculars . It was no longer significantly brighter and therefore could not be seen with the naked eye . From the middle / end of August its brightness then slowly decreased again. It could be observed telescopically until June 2015.

Scientific evaluation

With the 305-m radio telescope in Arecibo 2014 measurements were in the period from May 10 to July 31 spectrum of OH - molecules at a wavelength performed cm by 18 in order to deduce the gas production rate and its propagation velocity.

With the 0.6 m Trappist telescope ( TRAnsiting Planets and PlanetesImal Small Telescope ) of the La Silla Observatory of the European Southern Observatory in Chile and special filters, the outgassing rate, the production rate of dust and the spatial distribution of molecules such as OH, NH , CN, C 2 , C 3 and ions such as CO + are measured.

The comet was observed from the stratosphere by a balloon- borne 0.8 m telescope at the Balloon Observation Platform for Planetary Science (BOPPS) in New Mexico . The measurements were carried out in the infrared at a wavelength as emitted by water molecules. In the process, however, a super-hot dust cover was found around the comet, which only showed a broadband spectrum, but no emission lines .

With the Solar Wind Anisotropies (SWAN) camera on board the Solar and Heliospheric Observatory (SOHO) recordings were made, from which the production rate of water depending on the distance from the sun of the comet was derived. The rate of water production was also measured with the SPICAV UV spectrometer on board the Venus Express satellite while it was circling Venus .

UV spectra recorded with the Subaru telescope on Mauna Kea were evaluated to determine the ratio between the isotopes 14 N / 15 N in the ammonia emitted by the comet .

Orbit

For the comet, an elliptical orbit could be determined from 4803 observation data over a period of 1 ¼ years , which is inclined by around 156 ° to the ecliptic . The comet's orbit is thus slightly inclined to the planets of the planets, and it runs through its orbit in the opposite direction (retrograde) relative to these. At the point closest to the Sun ( perihelion ), which the comet passed on July 2, 2014, it was about 99.3 million km from the Sun and was just within the range of the orbit of Venus. On March 21st, it had already approached Mars to about 111.0 million km , and on April 5, it had approached Earth for the first time to about 0.96  AU / 143.6 million km .

After the perihelion, the comet passed Venus on July 13 at an unusually short distance of only about 12.7 million km. It had already come close to the orbit of Venus within 7.4 million km on July 7, but Venus only reached this point of its orbit 15 days later.

On July 20, Mercury was passed at a distance of about 68.1 million km and on August 28, the comet reached the closest approach to Earth at about 0.59  AU / 84.4 million km.

The comet moves in an extremely elongated elliptical orbit around the sun. According to the orbital elements , which are afflicted with a certain uncertainty and taking into account non-gravitational forces , its orbit still had an eccentricity of around 0.99918 and a semi-major axis of around 808 AU long before its passage through the inner solar system in 2014 , so that its orbital period was around 23,000 years ago. Due to the gravitational pull of the planets, in particular due to the relatively close passages of Saturn on July 26, 2012 at a distance of about 2 ¾ AU, at Jupiter on July 27, 2014 in about 4 ½ AU distance and again on Saturn on September 21, 2017 in however, at a distance of about 3 seine AU, its orbital eccentricity is reduced to about 0.99868 and its semi-major axis to about 504 AU, so that its orbital period is shortened to about 11,300 years.

See also

Web links

Commons : C / 2014 E2  - Collection of Images, Videos and Audio Files

Individual evidence

  1. ↑ B. King: New Comet Jacques May Pass 8.4 million miles from Venus this July. In: Universe Today. March 15, 2014, accessed on July 15, 2020 .
  2. ↑ Comet Jacques C / 2014 E2. In: kometen.info. August 18, 2014, accessed July 15, 2020 .
  3. ^ AJ Lovell, ES Howell: Radio OH Observations of Recent Bright Comets from Arecibo. In: American Astronomical Society, DPS meeting # 46. id. 209.11, 2014. bibcode : 2014DPS .... 4620911L
  4. ↑ E. Jehin, C. Opitom, J. Manfroid, D. Hutsemékers, M. Gillon: The TRAPPIST comet survey in 2014. In: American Astronomical Society, DPS meeting # 46th id. 209.21, 2014. bibcode : 2014DPS .... 4620921J
  5. ↑ AF Cheng, CA Hibbitts, R. Espiritu, R. McMichael, Z. Fletcher, P. Bernasconi, JD Adams, CM Lisse, ML Sitko, R. Fernandes, EF Young, T. Kremic: Stratospheric balloon observations of comets C / 2013 A1 (Siding Spring), C / 2014 E2 (Jacques), and Ceres. In: Icarus. Volume 281, 2017, pp. 404-416 doi: 10.1016 / j.icarus.2016.08.007 .
  6. ↑ MR Combi, TT Mäkinen, J.-L. Bertaux, E. Quémerais, S. Ferron, M. Avery, C. Wright: Water production activity of nine long-period comets from SOHO / SWAN observations of hydrogen Lyman-alpha: 2013–2016. In: Icarus. Volume 300, 2018, pp. 33-46 doi: 10.1016 / j.icarus.2017.08.035 .
  7. ↑ J.-Y. Chaufray, J.-L. Bertaux: UV cometary observations by SPICAV on Venus Express. In: EPSC Abstracts. Volume 10, EPSC2015-88, 2015. ( PDF; 131 kB )
  8. ↑ Y. Shinnaka, H. Kawakita, E. Jehin, A. Decock, D. Hutsemékers, J. Manfroid, A. Arai: Nitrogen isotopic ratios of NH 2 in comets: implication for 15 N-fractionation in cometary ammonia. In: Monthly Notices of the Royal Astronomical Society. Volume 462, 2016, pp. S195 – S209 doi: 10.1093 / mnras / stw2410 . ( PDF; 3.35 MB )
  9. ↑ C / 2014 E2 (Jacques) in the Small-Body Database of the Jet Propulsion Laboratory (English).Template: JPL Small-Body Database Browser / Maintenance / Alt
  10. ↑ SOLEX 12.1 by A. Vitagliano. Retrieved July 9, 2020 .