Draco Dwarf

RA:

17 : 20.1

Dec:

+57 : 55

Type:

dE0 pec

RV:

-31 km/s

Distance:

280 kly

Apparent Dimension:

51.0 x 31.0 arc min

Diameter:

Brightness:

9.9 m_v

Abs. Mag:

Mass:

The Draco Dwarf was discovered by Albert G. Wilson of Lowell Observatory, who had already discovered dwarf galaxy Leo I some years earlier, on photographic plates from the National Geographic Society - Palomar Observatory Sky Survey (POSS) in 1954, together with the Ursa Minor Dwarf (Wilson 1955). It was subsequently investigated by Walter Baade and Henrietta H. Swope (1961) who found over 260 variables (including 5 RR Lyrae stars), and by Paul W. Hodge (1964) who analysed the distribution of its stars.

The Draco Dwarf is one of the faintest galaxies known. As a dwarf elliptical or dwarf spheroidal galaxy, it contains only an old population of stars and no significant amount of interstellar matter. It is one of the small satellite galaxies of our Milky Way Galaxy, at a distance of about 280,000 light years.

The image in this page was obtained by Mischa Schirmer, taken July 3/4, 2007 from Roque de los Muchachos, La Palma with FFC on MM mount and ST-10XME CCD camera. exposed 5:35 (LRGB: L=25*300s, RGB=(7x7x7)*600 s unbinned). ALso see higher-contrast b/w and hires version.

Links:

• The Draco Dwarf Spheroidal Galaxy - dark matter dominated or tidally disrupted ? - Sloan Digital Sky Survey

• W. Baade and H.H. Swope, 1961. The Draco System, a Dwarf Galaxy. Astronomical Journal, Vol. 66, No. 7, pp. 300-347 (09/1961) [ADS: 1961AJ.....66..300B]
• Paul W. Hodge, 1964. Distribution of stars in the Draco dwarf galaxy. Astronomical Journal, Vol. 69, No. 10, pp. 853-857 (12/1964) [ADS: 1964AJ.....69..853H]
• A.G. Wilson, 1955. Sculptor-Type Systems in the Local Group of Galaxies. Publications of the Astronomical Society of the Pacific, Vol. 67, No. 394, pp. 27-29 (02/1955) [ADS: 1955PASP...67...27W]

Last Modification: May 26, 2002