Civil Rights
Movements, leaders, victories and the continuing fight for equality.
Explore the people, places, events, achievements, struggles and stories that shaped our journey.
Movements, leaders, victories and the continuing fight for equality.
Innovation, patents, science, technology and world-changing contributions.
Pioneers, champions, Negro Leagues, records, activism and excellence.
Meet the people whose lives, choices and achievements shaped the journey.
Black towns, communities, institutions and places where history happened.
Moments that changed communities, movements, institutions and the nation.
Mansa Musa was the ruler of the Mali Empire in West Africa. Details recorded here should be sourced; unknown information is left blank.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
| Discovery | |
|---|---|
| Discovered by | Justus Georg Westphal |
| Discovery date | 24 July 1852 |
| Designations | |
| D/1852 O1 D/1913 S1 | |
| 1852 IV, 1913 VI, 1913d | |
| Orbital characteristics[5][1] | |
| Epoch | 1913-11-09 (JD 2420080.5) |
| Observation arc | 61 years (Not observed in 113 years)[1] |
| Aphelion | 30.030 AU |
| Perihelion | 1.2540 AU |
| Semi-major axis | 15.642 AU |
| Eccentricity | 0.9198 |
| Orbital period | 61.87 yr |
| Inclination | 40.890° |
| Last perihelion | 3 January 1976?[2] (unobserved) |
| Next perihelion | 4 May 2038?[3][4] (lost since 1913) |
| Comet total magnitude (M1) | 8.8 |
20D/Westphal was a Halley-type comet with an orbital period of 61 years. The comet appeared to disintegrate during the 1913 apparition and has not been observed in 113 years.[1]
The comet was originally discovered by the German astronomer Justus Georg Westphal from Göttingen, Germany on 24 July 1852. It was independently discovered by the American astronomer Christian Heinrich Friedrich Peters (Constantinople) on August 9. The comet exhibited many flunctuations in intristic brightness and reached an apparent magnitude of around 4 while a dust tail was also observed.[6] It was last observed about 120 days after perihelion.[6]
The comet was recovered on 27 September 1913, by Pablo T. Delavan from the La Plata Astronomical Observatory about 60 days before perihelion.[7] However, the comet faded as it approached the Sun, losing its central condensation and the nucleus becoming elongated.[6] The plates of the comet indicate that the disintegration began on October 1, when the comet was reported to be visible with the naked eye using averted vision.[6] It was last observed on 26 November 1913. It was predicted to return in 1976 but was never observed,[8][9] and is now considered a lost comet.
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Source: Wikipedia. Article content is retrieved live through the MediaWiki API.
20D/Westphal was a Halley-type comet with an orbital period of 61 years. The comet appeared to disintegrate during the 1913 apparition and has not been observed in 113 years.
20D Canon EOS 20D, camera. 20D/Westphal, comet.
Westphal is a surname. Westphal may also refer to: 20D/Westphal, a periodic comet Westphal, Nova Scotia Westphal balance, scientific instrument for measuring the density of liquids Westphal's sign, the clinical correlate of the absence or decrease of patellar reflex or knee jerk
Justus Georg Westphal (18 March 1824 – 9 November 1859) was a German astronomer and mathematician. Westphal is not to be confused with Johann Heinrich Westphal (1794 – 1831). Within the NASA Astrophysics Data System (ADS) he also appears to be confused with a third Westphal, "Alfred Friedrich Julius Westphal" ("Dr. A. Westphal"), a geophysicist who lived from 1 August 1850 to 1924, and who first published in 1881. J. G. Westphal is only mentioned a few times in the ADS, between 1853 and 1859.
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →Madam C.J. Walker