• Source: 1319 Disa

1319 Disa, provisional designation 1934 FO, is a carbonaceous asteroid from the outer region of the asteroid belt, approximately 25 kilometers in diameter. It was discovered on 19 March 1934, by English-born, South African astronomer Cyril Jackson at Johannesburg Observatory in South Africa. It is named for the orchid Disa.




Orbit


Disa orbits the Sun in the outer main-belt at a distance of 2.4–3.6 AU once every 5 years and 2 months (1,884 days). Its orbit has an eccentricity of 0.21 and an inclination of 3° with respect to the ecliptic. It was first identified as A908 EA at Heidelberg Observatory in 1908. The body's observation arc begins in 1929, when it was identified as 1929 GE at the discovering observatory, 6 years prior to its official discovery observation.




Physical characteristics






= Rotation period

=
A rotational lightcurve of Disa was obtained by American astronomer Brian D. Warner at his Palmer Divide Observatory in March 2006, and by French amateur astronomer Pierre Antonini in February 2011, respectively. Analysis of both lightcurves gave a well-defined rotation period of 7.08 hours with a brightness variation of 0.26 and 0.27 magnitude (U=3/3).
In September 2013, photometric observations in the R-band at the Palomar Transient Factory gave a concurring lightcurve of 7.082 hours and an amplitude of 0.24 magnitude (U=2).




= Diameter, albedo and spectral type

=
According to the surveys carried out by the Japanese Akari satellite, and the 2014-results by NASA's Wide-field Infrared Survey Explorer with its subsequent NEOWISE mission, Disa measures 24.00 and 25.65 kilometers in diameter, and its surface has an albedo of 0.116 and 0.097, respectively.
The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous C-type asteroids of 0.057 and calculates a diameter of 40.33 kilometers with an absolute magnitude of 10.7. Preliminary results by NEOWISE also characterized the body as a dark and reddish P-type asteroid.




Naming


This minor planet was named after Disa, also known as "African weed-orchid", a large genus of more than a hundred tropical orchids, common in southern Africa. In 1955, this naming citation was also published by Paul Herget in The Names of the Minor Planets (H 120).




Notes






References






External links


Asteroid Lightcurve Database (LCDB), query form (info Archived 16 December 2017 at the Wayback Machine)
Dictionary of Minor Planet Names, Google books
Asteroids and comets rotation curves, CdR – Observatoire de Genève, Raoul Behrend
Discovery Circumstances: Numbered Minor Planets (1)-(5000) – Minor Planet Center
1319 Disa at AstDyS-2, Asteroids—Dynamic Site
Ephemeris · Observation prediction · Orbital info · Proper elements · Observational info
1319 Disa at the JPL Small-Body Database

Kata Kunci Pencarian:

• Sejarah Aceh
• 1319 Disa
• Disa (disambiguation)
• Cyril Jackson (astronomer)
• Meanings of minor-planet names: 1001–2000
• List of minor planets: 1001–2000
• Union Observatory
• 1318 Nerina
• List of named minor planets: 1000–1999
• List of named minor planets: D
• Maxwell Moss